WorldWideScience

Sample records for Tar Sand Tailings

  1. Revegetation and management of tailings sand slopes from tar sand extraction: 1978 results

    Energy Technology Data Exchange (ETDEWEB)

    Rowell, M J

    1979-01-01

    The results are reported of research into the revegetation of two areas on a steeply sloping dike composed of tailings sand from tar sand extraction at the Great Canadian Oil Sand Limited plant at Fort McMurray, Alberta. One area was seeded with three pasture grasses and two legumes in 1971 after the slope surface had been mixed with peat to a depth of 15 cm. A second area had been amended with peat or peat and overburden and differing rates of fertilizer added. A mix containing nine grasses, four legumes, and oats, as a companion crop, was seeded in July 1976. The objectives of the research were to study methods for the establishment of a stable vegetative cover that would prevent erosion of the slope and, in time, might become a self maintaining unit. Tillage of soil amendments to a depth of 15 cm and 30 cm were compared in promoting deeper rooting and stabilizing of the slope.

  2. Technology unlocks tar sands energy

    Energy Technology Data Exchange (ETDEWEB)

    Law, C

    1967-09-25

    Tar sand processing technology has been developed primarily in the categories of extraction techniques and in-situ processing. In October, a $235 million venture into tar sand processing will be inspected by visitors from many points on the globe. A synthetic crude of premium quality will be flowing through a 16-in. pipeline from the Tar Island plant site of Great Canadian Oil Sands to Edmonton. This processing plant uses an extractive mining technique. The tar sand pay zone in this area averages approximately 150 ft in thickness with a 50-ft overburden. It has been estimated that the tar sands cannot be exploited when the formation thickness is less than 100 ft and overburden exceeds the same amount. This indicates that extraction techniques can only be used to recover approximately 15% of the tar sand deposits. An in-situ recovery technique developed by Shell of Canada is discussed in detail. In essence it is selective hydraulic fracturing, followed by the injection of emulsifying chemicals and steam.

  3. In situ recovery of oil from Utah tar sand: a summary of tar sand research at the Laramie Energy Technology Center

    Energy Technology Data Exchange (ETDEWEB)

    Marchant, L.C.; Westhoff, J.D.

    1985-10-01

    This report describes work done by the United States Department of Energy's Laramie Energy Technology Center from 1971 through 1982 to develop technology for future recovery of oil from US tar sands. Work was concentrated on major US tar sand deposits that are found in Utah. Major objectives of the program were as follows: determine the feasibility of in situ recovery methods applied to tar sand deposits; and establish a system for classifying tar sand deposits relative to those characteristics that would affect the design and operation of various in situ recovery processes. Contents of this report include: (1) characterization of Utah tar sand; (2) laboratory extraction studies relative to Utah tar sand in situ methods; (3) geological site evaluation; (4) environmental assessments and water availability; (5) reverse combustion field experiment, TS-1C; (6) a reverse combustion followed by forward combustion field experiment, TS-2C; (7) tar sand permeability enhancement studies; (8) two-well steam injection experiment; (9) in situ steam-flood experiment, TS-1S; (10) design of a tar sand field experiment for air-stream co-injection, TS-4; (11) wastewater treatment and oil analyses; (12) economic evaluation of an in situ tar sand recovery process; and (13) appendix I (extraction studies involving Utah tar sands, surface methods). 70 figs., 68 tabs.

  4. Production of oil from Intermountain West tar sands deposits

    Energy Technology Data Exchange (ETDEWEB)

    Glassett, J.M.; Glassett, J.A.

    1976-03-01

    Six tar sand deposits in the Intermountain West, each containing more than one billion barrels of oil in place, are identified. All of these deposits are in eastern Utah and contain a total of twenty-eight billion barrels of oil. The names of the six deposits arranged in descending order of desirability for large-scale surface-mining oil recovery operations are as follows: Sunnyside, Tar Sand Triangle, Asphalt Ridge, P.R. Spring, Circle Cliffs, and Hill Creek. An overview of each deposit is presented including geology, surface-mining variables, chemical processing variables, environmental aspects, and economics. A comparison of Utah tar sands and Athabasca, Alberta, Canada tar sands is also presented.

  5. Creating fluid injectivity in tar sands formations

    Science.gov (United States)

    Stegemeier, George Leo; Beer, Gary Lee; Zhang, Etuan

    2010-06-08

    Methods for treating a tar sands formation are described herein. Methods for treating a tar sands may include heating a portion of a hydrocarbon layer in the formation from one or more heaters located in the portion. The heat may be controlled to increase the permeability of at least part of the portion to create an injection zone in the portion with an average permeability sufficient to allow injection of a fluid through the injection zone. A drive fluid and/or an oxidizing fluid may be provided into the injection zone. At least some hydrocarbons are produced from the portion.

  6. Microbial metabolism alters pore water chemistry and increases consolidation of oil sands tailings.

    Science.gov (United States)

    Arkell, Nicholas; Kuznetsov, Petr; Kuznetsova, Alsu; Foght, Julia M; Siddique, Tariq

    2015-01-01

    Tailings produced during bitumen extraction from surface-mined oil sands ores (tar sands) comprise an aqueous suspension of clay particles that remain dispersed for decades in tailings ponds. Slow consolidation of the clays hinders water recovery for reuse and retards volume reduction, thereby increasing the environmental footprint of tailings ponds. We investigated mechanisms of tailings consolidation and revealed that indigenous anaerobic microorganisms altered porewater chemistry by producing CO and CH during metabolism of acetate added as a labile carbon amendment. Entrapped biogenic CO decreased tailings pH, thereby increasing calcium (Ca) and magnesium (Mg) cations and bicarbonate (HCO) concentrations in the porewater through dissolution of carbonate minerals. Soluble ions increased the porewater ionic strength, which, with higher exchangeable Ca and Mg, decreased the diffuse double layer of clays and increased consolidation of tailings compared with unamended tailings in which little microbial activity was observed. These results are relevant to effective tailings pond management strategies. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  7. Analysis of the environmental control technology for tar sand development

    Energy Technology Data Exchange (ETDEWEB)

    de Nevers, N.; Glenne, B.; Bryner, C.

    1979-06-01

    The environmental technology for control of air pollution, water pollution, and for the disposal, stabilization, and vegetation of the waste tar sand were thoroughly investigated. Although some difficulties may be encountered in any of these undertakings, it seems clear that the air and water pollution problems can be solved to meet any applicable standard. Currently there are two large-scale plants producing liquid fuels from tar sands in Alberta, Canada which use similar technology involving surface mining, hot water extraction, and surface disposal of waste sand. These projects all meet the Canadian environmental control regulations in force at the time they began. The largest US deposits of tar sands are much smaller than the Canadian; 95 percent are located in the state of Utah. Their economics do not appear as attractive as the Canadian deposits. The environmental control costs are not large enough to make an otherwise economic project uneconomic. The most serious environmental conflict likely to occur over the recovery of liquid fuels from the US deposits of tar sands is that caused by the proximity of the deposits to national parks, national monuments, and a national recreation area in Utah. These areas have very stringent air pollution requirements; and even if the air pollution control requirements can be met, there may still be adequate opposition to large-scale mining ventures in these areas to prevent their commercial exploitation. Another environmental constraint may be water rights availability.Essentially all of the water running in the Colorado river basin is now legally allocated. Barring new interpretations of the legality of water rights purchase, Utah tar sands developments should be able to obtain water by purchasing existing irrigation water rights.

  8. The extraction of bitumen from western tar sands. Annual report, July 1990--July 1991

    Energy Technology Data Exchange (ETDEWEB)

    Oblad, A.G.; Bunger, J.W.; Deo, M.D.; Hanson, F.V.; Miller, J.D.; Seader, J.D.

    1992-04-01

    Contents of this report include the following: executive summary; characterization of the native bitumen from the Whiterocks oil sand deposit; influence of carboxylic acid content on bitumen viscosity; water based oil sand separation technology; extraction of bitumen from western oil sands by an energy-efficient thermal method; large- diameter fluidized bed reactor studies; rotary kiln pyrolysis of oil sand; catalytic upgrading of bitumen and bitumen derived liquids; ebullieted bed hydrotreating and hydrocracking; super critical fluid extraction; bitumen upgrading; 232 references; Appendix A--Whiterocks tar sand deposit bibliography; Appendix B--Asphalt Ridge tar sand deposit bibliography; and Appendix C--University of Utah tar sands bibliography.

  9. Creating and maintaining a gas cap in tar sands formations

    Science.gov (United States)

    Vinegar, Harold J.; Karanikas, John Michael; Dinkoruk, Deniz Sumnu; Wellington, Scott Lee

    2010-03-16

    Methods for treating a tar sands formation are disclosed herein. Methods for treating a tar sands formation may include providing heat to at least part of a hydrocarbon layer in the formation from one or more heaters located in the formation. Pressure may be allowed to increase in an upper portion of the formation to provide a gas cap in the upper portion. At least some hydrocarbons are produced from a lower portion of the formation.

  10. Potential impacts to perennial springs from tar sand mining, processing, and disposal on the Tavaputs Plateau, Utah, USA

    International Nuclear Information System (INIS)

    Johnson, William P.; Frederick, Logan E.; Millington, Mallory R.; Vala, David; Reese, Barbara K.; Freedman, Dina R.; Stenten, Christina J.; Trauscht, Jacob S.; Tingey, Christopher E.; Kip Solomon, D.; Fernandez, Diego P.; Bowen, Gabriel J.

    2015-01-01

    Similar to fracking, the development of tar sand mining in the U.S. has moved faster than understanding of potential water quality impacts. Potential water quality impacts of tar sand mining, processing, and disposal to springs in canyons incised approximately 200 m into the Tavaputs Plateau, at the Uinta Basin southern rim, Utah, USA, were evaluated by hydrogeochemical sampling to determine potential sources of recharge, and chemical thermodynamic estimations to determine potential changes in transfer of bitumen compounds to water. Because the ridgetops in an area of the Tavaputs Plateau named PR Spring are starting to be developed for their tar sand resource, there is concern for potential hydrologic connection between these ridgetops and perennial springs in adjacent canyons on which depend ranching families, livestock, wildlife and recreationalists. Samples were collected from perennial springs to examine possible progression with elevation of parameters such as temperature, specific conductance, pH, dissolved oxygen, isotopic tracers of phase change, water-rock interaction, and age since recharge. The groundwater age dates indicate that the springs are recharged locally. The progression of hydrogeochemical parameters with elevation, in combination with the relatively short groundwater residence times, indicate that the recharge zone for these springs includes the surrounding ridges, and thereby suggests a hydrologic connection between the mining, processing, disposal area and the springs. Estimations based on chemical thermodynamic approaches indicate that bitumen compounds will have greatly enhanced solubility in water that comes into contact with the residual bitumen–solvent mixture in disposed tailings relative to water that currently comes into contact with natural tar. - Highlights: • The potential water quality impacts of the first US tar sand development are considered. • Analyses of perennial springs in adjacent canyons indicate hydrologic

  11. Potential impacts to perennial springs from tar sand mining, processing, and disposal on the Tavaputs Plateau, Utah, USA

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, William P.; Frederick, Logan E.; Millington, Mallory R. [University of Utah, Department of Geology & Geophysics, Salt lake City, UT 84112 (United States); Vala, David [Murray High School, Murray, UT 84107 (United States); Reese, Barbara K. [Butler Middle School, Cottonwood Heights, UT 84121 (United States); Freedman, Dina R. [Hillside Middle School, Salt Lake City, UT 84108 (United States); Stenten, Christina J. [Draper Park Middle School, Draper, UT 84020 (United States); Trauscht, Jacob S.; Tingey, Christopher E.; Kip Solomon, D.; Fernandez, Diego P.; Bowen, Gabriel J. [University of Utah, Department of Geology & Geophysics, Salt lake City, UT 84112 (United States)

    2015-11-01

    Similar to fracking, the development of tar sand mining in the U.S. has moved faster than understanding of potential water quality impacts. Potential water quality impacts of tar sand mining, processing, and disposal to springs in canyons incised approximately 200 m into the Tavaputs Plateau, at the Uinta Basin southern rim, Utah, USA, were evaluated by hydrogeochemical sampling to determine potential sources of recharge, and chemical thermodynamic estimations to determine potential changes in transfer of bitumen compounds to water. Because the ridgetops in an area of the Tavaputs Plateau named PR Spring are starting to be developed for their tar sand resource, there is concern for potential hydrologic connection between these ridgetops and perennial springs in adjacent canyons on which depend ranching families, livestock, wildlife and recreationalists. Samples were collected from perennial springs to examine possible progression with elevation of parameters such as temperature, specific conductance, pH, dissolved oxygen, isotopic tracers of phase change, water-rock interaction, and age since recharge. The groundwater age dates indicate that the springs are recharged locally. The progression of hydrogeochemical parameters with elevation, in combination with the relatively short groundwater residence times, indicate that the recharge zone for these springs includes the surrounding ridges, and thereby suggests a hydrologic connection between the mining, processing, disposal area and the springs. Estimations based on chemical thermodynamic approaches indicate that bitumen compounds will have greatly enhanced solubility in water that comes into contact with the residual bitumen–solvent mixture in disposed tailings relative to water that currently comes into contact with natural tar. - Highlights: • The potential water quality impacts of the first US tar sand development are considered. • Analyses of perennial springs in adjacent canyons indicate hydrologic

  12. Solvent extraction of Southern US tar sands

    Energy Technology Data Exchange (ETDEWEB)

    Penney, W.R.

    1990-01-01

    The Department of Chemical Engineering at the University of Arkansas, in association with Diversified Petroleum Recovery, Inc. (DPR) of Little Rock, Arkansas, has been developing a solvent extraction process for the recovery of bitumen from tar sands for the past five years. The unique feature of the process is that the bitumen is recovered from the solvent by contacting with a co-solvent, which causes the bitumen to precipitate. The overall purpose of this project is to study both the technical and economic feasibility of applying this technology for recovery of bitumen from tar sands by (1) investigating the socioeconmic factors which affect (a) plant siting and (b) the market value of recovered bitumen; (2) operating a process demonstration unit at the rate of 1 lb/hr recovered bitumen while producing clean sand and recyclable solvents; and (3) determine the economic conditions which will make a bitumen recovery project economical. DPR has analyzed the historical trends of domestic production, consumption, discoveries and reserves of crude oil. They have started an investigation of the volatility in the price of crude oil and of gasoline prices and of the differential between gasoline and crude oil. DPR continues to analyze the geographical movement and demand for asphalt products. Utah does not appear economically attractive as a site for a bitumen from tar sands asphalt plant. Oklahoma sites are now being studied. This report also contains the quarterly progress report from a University of Nevada study to determine bitumen composition, oxygen uptake rates, and viscosities of Alabama and Utah bitumens. Both reports have been indexed separately for inclusion on the data base.

  13. Paleontological overview of oil shale and tar sands areas in Colorado, Utah, and Wyoming.

    Energy Technology Data Exchange (ETDEWEB)

    Murphey, P. C.; Daitch, D.; Environmental Science Division

    2009-02-11

    In August 2005, the U.S. Congress enacted the Energy Policy Act of 2005, Public Law 109-58. In Section 369 of this Act, also known as the ''Oil Shale, Tar Sands, and Other Strategic Unconventional Fuels Act of 2005,'' Congress declared that oil shale and tar sands (and other unconventional fuels) are strategically important domestic energy resources that should be developed to reduce the nation's growing dependence on oil from politically and economically unstable foreign sources. In addition, Congress declared that both research- and commercial-scale development of oil shale and tar sands should (1) be conducted in an environmentally sound manner using management practices that will minimize potential impacts, (2) occur with an emphasis on sustainability, and (3) benefit the United States while taking into account concerns of the affected states and communities. To support this declaration of policy, Congress directed the Secretary of the Interior to undertake a series of steps, several of which are directly related to the development of a commercial leasing program for oil shale and tar sands. One of these steps was the completion of a programmatic environmental impact statement (PEIS) to analyze the impacts of a commercial leasing program for oil shale and tar sands resources on public lands, with an emphasis on the most geologically prospective lands in Colorado, Utah, and Wyoming. For oil shale, the scope of the PEIS analysis includes public lands within the Green River, Washakie, Uinta, and Piceance Creek Basins. For tar sands, the scope includes Special Tar Sand Areas (STSAs) located in Utah. This paleontological resources overview report was prepared in support of the Oil Shale and Tar Sands Resource Management Plan Amendments to Address Land Use Allocations in Colorado, Utah, and Wyoming and PEIS, and it is intended to be used by Bureau of Land Management (BLM) regional paleontologists and field office staff to support future

  14. Athabasca tar sand reservoir properties derived from cores and logs

    International Nuclear Information System (INIS)

    Woodhouse, R.

    1976-01-01

    Log interpretation parameters for the Athabasca Tar Sand Lease No. 24 have been determined by careful correlation with Dean and Stark core analysis data. Significant expansion of Athabasca cores occurs as overburden pressure is removed. In the more shaly sands the core analysis procedures remove adsorbed water from the clays leading to further overestimation of porosity and free water volume. Log interpretation parameters (R/sub w/ = 0.5 ohm . m and m = n = 1.5) were defined by correlation with the weight of tar as a fraction of the weight of rock solids (grain or dry weight fraction of tar). This quantity is independent of the water content of the cores, whereas porosity and the weight of tar as a fraction of the bulk weight of fluids plus solids (bulk weight fraction) are both dependent on water content. Charts are provided for the conversion of bulk weight fraction of fluids to porosity; grain weight fraction of fluids to porosity; log derived porosity and core grain weight tar to water saturation. Example results show that the core analysis grain weight fraction of tar is adequately matched by the log analyses. The log results provide a better representation of the reservoir fluid volumes than the core analysis data

  15. Research and information needs for management of tar sands development. Interim report Apr-May 83

    Energy Technology Data Exchange (ETDEWEB)

    1983-05-01

    The report discusses important research and information needs for federal lease management of lands with tar sands resources. Short-term needs include more complete definition and characterization of deposits, hydrology, and regions downwind from tar sands areas. Longer-term needs include demonstration-scale operations to resolve production, waste management, and reclamation problems and to provide opportunities for measurement, analysis, and assessment of mining and processing wastes and emissions. Most of the known federal tar sands resource is in eastern Utah and contains about 25 billion barrels of bitumen. Recent legislation provides that existing mining claims and oil and gas leases may be converted to combined hydrocarbon leases including tar sands. Federal approval, which must be applied for by November 1983, is a condition for conversion.

  16. Heavy crude and tar sands - the long-term oil reserve

    Energy Technology Data Exchange (ETDEWEB)

    Barnea, J

    1984-10-01

    It appears that heavy crude and tar sands occur in many sedimentary areas, and estimates of known world-wide quantities exceed those known for conventional light crude resources. Although there are not precise figures available, production could be as high as three million barrels per day, with Venezuela, the US, and Canada the largest producers. There are different scales to measure the costs of production because of differences in the quality of various types of heavy crude and tar sands. Economic development of these resources should banish fears of oil scarcity in the foreseeable future. A center for information exchange through international meetings and publications is under development.

  17. Coliquefaction of coal, tar sand bitumen and plastic (interaction among coal, bitumen and plastic); Sekitan/tar sand bitumen/plastic no kyoekika ni okeru kyozon busshitsu no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, H.; Okuyama, Y.; Matsubara, K. [NKK Corp., Tokyo (Japan); Kamo, T.; Sato, Y. [National Institute for Resources and Environment, Tsukuba (Japan)

    1996-10-28

    For the improvement of economy, coliquefaction of coal, tar sand bitumen and plastic was performed under low hydrogen pressure, to investigate the influence of interaction among these on the liquefaction characteristics. For comparison, coliquefaction was also performed under the hydrogen pressure same as the NEDOL process. In addition, for clarifying its reaction mechanism, coliquefaction of dibenzyl and plastic was performed as a model experiment, to illustrate the distribution of products and composition of oil, and to discuss the interaction between dibenzyl and various plastics, and between various plastics. Under direct coal liquefaction conditions, coprocessing of Tanito Harum coal, Athabasca tar sand and plastic was carried out under low hydrogen pressure with an autoclave. The observed value of oil yield was higher than the calculated value based on the values from separate liquefaction of coal and plastic, which suggested the interaction between coal and the mixed plastic. The results of coliquefaction of coal, tar sand bitumen and plastic could be explained from the obtained oil yield and its composition by the coliquefaction of dibenzyl and plastic. 2 refs., 3 tabs.

  18. A role for nuclear energy in the recovery of oil from the tar sands of Alberta

    International Nuclear Information System (INIS)

    Puttagunta, V.R.; Sochaski, R.O.; Robertson, R.F.S.

    1976-12-01

    Techniques of oil recovery from the tar sands and the energy requirements of this operation are described. Fossil fuels, and CANDU reactors are examined as competitive sources of energy for the tar sands plants. The CANDU-OCR reactor appears to have the necessary flexibility to fit into many of the possible methods of recovering oil from the tar sands. Cost comparisons of fossil and nuclear sources show that, for the supply of process steam, the nuclear source is competitive under the criteria of debt financing or low discount rates on capital, continued escalation, and long plant capital write-off period. (author)

  19. Tar sands showdown : Canada and the new politics of oil in an age of climate change

    International Nuclear Information System (INIS)

    Clarke, T.

    2009-01-01

    This book outlined the social and environmental issues facing the oil sands industry in Canada, including economic sovereignty, energy security, water rights and free trade. The tar sands have become vital to the Canadian economy, as they have the potential to increase Canada's foreign oil output by 4 to 5 times in the next 15 years. The author discussed the ecological and social impact of the Alberta tar sands and the real cost of development to Albertans and Canadians. Tar sands oil production generates more than 3 times the amount of greenhouse gas emissions than conventional oil production. The industry is also becoming a prime example of the abuse of water sources. The author emphasized the need to build an alternative energy future in an age of global warming. The main objective of this book was to help stimulate a nation-wide public debate about the tar sands and the critical issues at stake regarding Canada's energy future and an environmental strategy for more sustainable development. refs., tabs., figs.

  20. Big picture thinking in oil sands tailings disposal

    Energy Technology Data Exchange (ETDEWEB)

    Boswell, J. [Thurber Engineering Ltd., Calgary, AB (Canada)

    2010-07-01

    This PowerPoint presentation discussed methods of disposing oil sands tailings. Oil sands operators are currently challenged by a variety of legislative and environmental factors concerning the creation and disposal of oil sands tailings. The media has focused on the negative ecological impact of oil sands production, and technical issues are reducing the effect of some mitigation processes. Operators must learn to manage the interface between tailings production and removal, the environment, and public opinion. The successful management of oil sand tailings will include procedures designed to improve reclamation processes, understand environmental laws and regulations, and ensure that the cumulative impacts of tailings are mitigated. Geotechnical investigations, engineering designs and various auditing procedures can be used to develop tailings management plans. Environmental screening and impact assessments can be used to develop sustainable solutions. Public participation and environmental mediation is needed to integrate the public, environmental and technical tailings management strategies. Operators must ensure public accountability for all stakeholders. tabs., figs.

  1. Stuck in the tar sands : how the federal government's proposed climate change strategy lets oil companies off the hook

    International Nuclear Information System (INIS)

    2008-10-01

    The credibility of any federal climate change strategy must be measured against its ability to reduce emissions from the tar sands. However, the federal government has proposed a climate change strategy that would allow tar sands producers to double their total emissions over the next decade. This report discussed how the federal government's proposed climate change strategy lets oil companies off the hook. The report discussed the problems and harmful effects associated with tar sands development, including greenhouse gas emissions; water depletion and pollution; toxic air emissions; destruction of the boreal forest; violation of native rights; threat to energy security; and negative socio-economic spin-off from an overheated economy. The federal government's proposed strategy was also assessed in terms of its weak greenhouse gas targets; ignoring the recent growth in tar sands emissions; adopting intensity-based targets instead of hard caps on greenhouse gas pollution, allowing total emissions from the tar sands to keep climbing; putting off critical measures until 2018; awarding oil companies hundreds of millions of dollars in credits for meeting targets they have already adopted voluntarily; lowballing the price of oil and downplaying future growth in tar sands emissions; ignoring huge portions of the oil industry's greenhouse gas pollution; letting oil companies buy their way out at rockbottom prices instead of forcing them to reduce their own emissions; and subsidizing increased tar sands production. It was concluded that the federal government's proposed plan to reduce greenhouse gas emissions was inadequate, because it failed to crack down on rising greenhouse gas emissions from the tar sands, one of Canada's most carbon intensive and fastest growing industries. 29 refs., 1 appendix

  2. Heavy mineral concentration from oil sand tailings

    Energy Technology Data Exchange (ETDEWEB)

    Chachula, F.; Erasmus, N. [Titanium Corp. Inc., Regina, SK (Canada)

    2008-07-01

    This presentation described a unique technique to recover heavy minerals contained in the froth treatment tailings produced by oil sand mining extraction operations in Fort McMurray, Alberta. In an effort to process waste material into valuable products, Titanium Corporation is developing technology to recover heavy minerals, primarily zircon, and a portion of bitumen contained in the final stage of bitumen processing. The process technology is being developed to apply to all mined oil sands operations in the Fort McMurray region. In 2004, Titanium Corporation commissioned a pilot research facility at the Saskatchewan Research Council to test dry oil sands tailings. In 2005, a bulk sampling pilot plant was connected to the fresh oil sands tailings pipeline on-site in Fort McMurray, where washed sands containing heavy minerals were processed at a pilot facility. The mineral content in both deposited tailings and fresh pipeline tailings was assessed. Analysis of fresh tailings on a daily basis identified a constant proportion of zircon and higher levels of associated bitumen compared with the material in the deposited tailings. The process flow sheet design was then modified to remove bitumen from the heavy minerals and concentrate the minerals. A newly modified flotation process was shown to be a viable processing route to recover the heavy minerals from froth treatment tailings. 8 refs., 9 tabs., 12 figs.

  3. Geophysical applications for oil sand mine tailings management

    Energy Technology Data Exchange (ETDEWEB)

    Parker, D.; Bauman, P. [WorleyParsons, Calgary, AB (Canada)

    2009-07-01

    Geophysical techniques are applied throughout a mine's life cycle to facilitate siting, constructing and monitoring of tailings dumps and ponds. This presentation described 3 case studies from the Athabasca region in northeast Alberta that demonstrated some of the concerns associated with oil sand mine tailings, and the information that geophysical surveys can provide. The objectives of these studies were to determine the lateral and depth extents of elevated conductivities of soil and groundwater that have high salt concentration from the tailings sand pore fluid. Due to high chloride concentrations within the tailings material, salt within the root zone may affect vegetation. A terrain conductivity survey was designed to map the lateral extents of salinity impact, while an electrical resistivity tomography (ERT) survey was used to delineate the tailings sand leachate at depth. The proper management of oil sand tailings facilities is vital to the life cycle of a mine. It was concluded that geophysical techniques can be instrumental in managing several engineering and environmental challenges, from Pleistocene channel mapping, to tailings pond settling characteristics, to reclaiming tailings sands. 1 ref., 7 figs.

  4. In situ heat treatment of a tar sands formation after drive process treatment

    Science.gov (United States)

    Vinegar, Harold J.; Stanecki, John

    2010-09-21

    A method for treating a tar sands formation includes providing a drive fluid to a hydrocarbon containing layer of the tar sands formation to mobilize at least some hydrocarbons in the layer. At least some first hydrocarbons from the layer are produced. Heat is provided to the layer from one or more heaters located in the formation. At least some second hydrocarbons are produced from the layer of the formation. The second hydrocarbons include at least some hydrocarbons that are upgraded compared to the first hydrocarbons produced by using the drive fluid.

  5. Class I cultural resource overview for oil shale and tar sands areas in Colorado, Utah and Wyoming.

    Energy Technology Data Exchange (ETDEWEB)

    O' Rourke, D.; Kullen, D.; Gierek, L.; Wescott, K.; Greby, M.; Anast, G.; Nesta, M.; Walston, L.; Tate, R.; Azzarello, A.; Vinikour, B.; Van Lonkhuyzen, B.; Quinn, J.; Yuen, R.; Environmental Science Division

    2007-11-01

    In August 2005, the U.S. Congress enacted the Energy Policy Act of 2005, Public Law 109-58. In Section 369 of this Act, also known as the 'Oil Shale, Tar Sands, and Other Strategic Unconventional Fuels Act of 2005', Congress declared that oil shale and tar sands (and other unconventional fuels) are strategically important domestic energy resources that should be developed to reduce the nation's growing dependence on oil from politically and economically unstable foreign sources. The Bureau of Land Management (BLM) is developing a Programmatic Environmental Impact Statement (PEIS) to evaluate alternatives for establishing commercial oil shale and tar sands leasing programs in Colorado, Wyoming, and Utah. This PEIS evaluates the potential impacts of alternatives identifying BLM-administered lands as available for application for commercial leasing of oil shale resources within the three states and of tar sands resources within Utah. The scope of the analysis of the PEIS also includes an assessment of the potential effects of future commercial leasing. This Class I cultural resources study is in support of the Draft Oil Shale and Tar Sands Resource Management Plan Amendments to Address Land Use Allocations in Colorado, Utah, and Wyoming and Programmatic Environmental Impact Statement and is an attempt to synthesize archaeological data covering the most geologically prospective lands for oil shale and tar sands in Colorado, Utah, and Wyoming. This report is based solely on geographic information system (GIS) data held by the Colorado, Utah, and Wyoming State Historic Preservation Offices (SHPOs). The GIS data include the information that the BLM has provided to the SHPOs. The primary purpose of the Class I cultural resources overview is to provide information on the affected environment for the PEIS. Furthermore, this report provides recommendations to support planning decisions and the management of cultural resources that could be impacted by future

  6. Dewatering Behaviour of Fine Oil Sands Tailings : An Experimental Study

    NARCIS (Netherlands)

    Yao, Y.

    2016-01-01

    Oil sands tailings are a warm aqueous suspension of sand, silt, clay, residual bitumen and naphtha. The tailings are hydraulically transported and stored in tailing ponds where they segregate, with the sand settling from suspension forming beaches and the remaining tailings flowing to the middle of

  7. The search for a source rock for the giant Tar Sand triangle accumulation, southeastern Utah

    Science.gov (United States)

    Huntoon, J.E.; Hansley, P.L.; Naeser, N.D.

    1999-01-01

    A large proportion (about 36%) of the world's oil resource is contained in accumulations of heavy oil or tar. In these large deposits of degraded oil, the oil in place represents only a fraction of what was present at the time of accumulation. In many of these deposits, the source of the oil is unknown, and the oil is thought to have migrated over long distances to the reservoirs. The Tar Sand triangle in southeastern Utah contains the largest tar sand accumulation in the United States, with 6.3 billion bbl of heavy oil estimated to be in place. The deposit is thought to have originally contained 13-16 billion bbl prior to the biodegradation, water washing, and erosion that have taken place since the middle - late Tertiary. The source of the oil is unknown. The tar is primarily contained within the Lower Permian White Rim Sandstone, but extends into permeable parts of overlying and underlying beds. Oil is interpreted to have migrated into the White Rim sometime during the Tertiary when the formation was at a depth of approximately 3500 m. This conclusion is based on integration of fluid inclusion analysis, time-temperature reconstruction, and apatite fission-track modeling for the White Rim Sandstone. Homogenization temperatures cluster around 85-90??C for primary fluid inclusions in authigenic, nonferroan dolomite in the White Rim. The fluid inclusions are associated with fluorescent oil-bearing inclusions, indicating that dolomite precipitation was coeval with oil migration. Burial reconstruction suggests that the White Rim Sandstone reached its maximum burial depth from 60 to 24 Ma, and that maximum burial was followed by unroofing from 24 to 0 Ma. Time-temperature modeling indicates that the formation experienced temperatures of 85-90??C from about 35 to 40 Ma during maximum burial. Maximum formation temperatures of about 105-110??C were reached at about 24 Ma, just prior to unroofing. Thermal modeling is used to examine the history of potential source rocks

  8. Geology and resources of the Tar Sand Triangle, southeastern Utah

    Energy Technology Data Exchange (ETDEWEB)

    Dana, G.F.; Oliver, R.L.; Elliott, J.R.

    1984-05-01

    The Tar Sand Triangle is located in southeastern Utah between the Dirty Devil and Colorado Rivers and covers an area of about 200 square miles. The geology of the area consists of gently northwest dipping strata exposed in the box canyons and slopes of the canyonlands morphology. Strata in the area range in age from Jurassic to Permian. The majority of tar sand saturation is found in the Permian White Rim Sandstone Member of the Cutler Formation. The White Rim Sandstone Member consists of a clean, well-sorted sandstone which was deposited in a shallow marine environment. Resources were calculated from analytical data from the three coreholes drilled by the Laramie Energy Technology Center and other available data. The total in-place resources, determined from this study, are 6.3 billion barels. Previous estimates ranged from 2.9 to 16 million barrels. More coring and analyses will be necessary before a more accurate determination of resources can be attempted. 8 references, 11 figures, 7 tables.

  9. Heating tar sands formations to visbreaking temperatures

    Science.gov (United States)

    Karanikas, John Michael [Houston, TX; Colmenares, Tulio Rafael [Houston, TX; Zhang, Etuan [Houston, TX; Marino, Marian [Houston, TX; Roes, Augustinus Wilhelmus Maria [Houston, TX; Ryan, Robert Charles [Houston, TX; Beer, Gary Lee [Houston, TX; Dombrowski, Robert James [Houston, TX; Jaiswal, Namit [Houston, TX

    2009-12-22

    Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. The heat may be controlled so that at least a majority of the section reaches an average temperature of between 200.degree. C. and 240.degree. C., which results in visbreaking of at least some hydrocarbons in the section. At least some visbroken hydrocarbon fluids may be produced from the formation.

  10. Reclamation and closure of an oil sands tailings facility

    Energy Technology Data Exchange (ETDEWEB)

    Sobkowicz, J. [Thurber Engineering Ltd., Calgary, AB (Canada); Morgenstern, N. [Alberta Univ., Edmonton, AB (Canada)

    2010-07-01

    This PowerPoint presentation discussed methods of ensuring the successful reclamation of oil sands tailings facilities. Tailings should be reclaimed as mining proceeds in order to avoid an excessive accumulation of fluid fine tailings (FFT). The volume of mature fine tailings (MFT) in ponds should be limited in order to ensure effective tailings management. The reclaimed landforms should have good geotechnical stability and be comprised of self-sustaining native vegetation. Strength is needed to allow for timely capping and initial reclamation, and stiffness is required to minimize future settlement and to allow for the construction of a closure landscape. Reclamation strategies were presented for fines-dominated tailings; sand-depleted tailings; and sand-dominated tailings. Energy Resources Conservation Board (ERCB) criteria for tailings reclamation were discussed, and various monitoring and performance assessment strategies were presented. tabs., figs.

  11. Proceedings of the 2. international oil sands tailings conference

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    The tailings produced by oil sands extraction processes pose significant threats to the surrounding environment in addition to releasing greenhouse gases (GHGs) into the atmosphere. Recent directives have been established to reduce the amount of tailings produced at oil sands operations, and to ensure that tailings ponds are reclaimed in the most effective manner. This conference provided a forum for researchers and industry experts to discuss issues related to the management and reclamation of oil sands tailings. New technologies for dewatering tailings ponds were presented, and methods of analyzing the chemical properties of tailings were reviewed. The conference was divided into the following 7 sessions: (1) tailings properties, (2) tailings dewatering, (3) new concepts, (4) water and chemistry, (5) soft tailings stabilization and reclamation, (6) water treatment, and (7) new concepts 2. The conference featured 44 presentations, all of which have been catalogued separately for inclusion in this database. tabs., figs.

  12. Heating tar sands formations while controlling pressure

    Science.gov (United States)

    Stegemeier, George Leo [Houston, TX; Beer, Gary Lee [Houston, TX; Zhang, Etuan [Houston, TX

    2010-01-12

    Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. A pressure in the majority of the section may be maintained below a fracture pressure of the formation. The pressure in the majority of the section may be reduced to a selected pressure after the average temperature reaches a temperature that is above 240.degree. C. and is at or below pyrolysis temperatures of hydrocarbons in the section. At least some hydrocarbon fluids may be produced from the formation.

  13. A cost comparison of nuclear and fossil power for the Alberta tar sands

    International Nuclear Information System (INIS)

    Sochaski, R.O.; Smith, D.W.

    1977-04-01

    One technique envisaged for commercial development of the Alberta tar sands is in-situ removal of bitumen by injection of steam into the formation at high temperature and pressure. The 3000 MW of thermal power required for a typical 20 Gg/d plant could be supplied by a nuclear reactor. Accordingly, an economic comparison was made between a CANDU organic-cooled reactor and a conventional coal-fired station, using a variety of financial ground rules. This analysis shows that for debt-financed cases, nuclear power has essentially no economic competition from coal. For equity cases, the competitive position of a coal-fired station is heavily dependent on the cost of coal delivered to the tar sands area, discount rate, amortization period and inflation rate. (author)

  14. Oil sands tailings management project

    Energy Technology Data Exchange (ETDEWEB)

    Godwalt, C. [Alberta WaterSMART, Calgary, AB (Canada); Kotecha, P. [Suncor Energy Inc, Calgary, AB (Canada); Aumann, C. [Alberta Innovates - Technology Futures, Alberta Governement, AB (Canada)

    2010-11-15

    The Oil sands leadership initiative (OSLI) works with the Government of Alberta on the development of the oil sands industry, considering environmental, economical and social aspects. Water management was identified as one of most important areas to focus on. Alberta WaterSMART was requested to support the development and the management of projects resulting from the work done or underway in this field. The development of a regional water management solution stood out as the most interesting solution to obtain significant results. In the Athabasca Region, oil sands producers work independently on their water sourcing and disposal with particular attention to fresh water conservation and economics. The Athabasca River represents a source for mines and distant saline aquifers are the target of steam assisted gravity drainage (SAGD) operators. As part of a four-phase project aiming to study the environmental and economic footprint (EEF) benefit of alternatives for Athabasca oil sands production water supply and disposal, the purpose of the tailings water management project was to identify tailings treatment technologies that are ready to be implemented, and to design and evaluate solutions in order to improve regional oil sands production water sourcing and disposal. Alternatives were evaluated based on their total EEF, applying a lifecycle assessment methodology with a particular attention on the quantification of important performance indicators. 25 refs., 8 tabs., 40 figs.

  15. Oil sands tailings management project

    International Nuclear Information System (INIS)

    Godwalt, C.; Kotecha, P.; Aumann, C.

    2010-11-01

    The Oil sands leadership initiative (OSLI) works with the Government of Alberta on the development of the oil sands industry, considering environmental, economical and social aspects. Water management was identified as one of most important areas to focus on. Alberta WaterSMART was requested to support the development and the management of projects resulting from the work done or underway in this field. The development of a regional water management solution stood out as the most interesting solution to obtain significant results. In the Athabasca Region, oil sands producers work independently on their water sourcing and disposal with particular attention to fresh water conservation and economics. The Athabasca River represents a source for mines and distant saline aquifers are the target of steam assisted gravity drainage (SAGD) operators. As part of a four-phase project aiming to study the environmental and economic footprint (EEF) benefit of alternatives for Athabasca oil sands production water supply and disposal, the purpose of the tailings water management project was to identify tailings treatment technologies that are ready to be implemented, and to design and evaluate solutions in order to improve regional oil sands production water sourcing and disposal. Alternatives were evaluated based on their total EEF, applying a lifecycle assessment methodology with a particular attention on the quantification of important performance indicators. 25 refs., 8 tabs., 40 figs.

  16. Trace metals in heavy crude oils and tar sand bitumens

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, J.G.

    1990-11-28

    Fe, Ni, and V are considered trace impurities in heavy crude oils and tar sand bitumens. In order to understand the importance of these metals, we have examined several properties: (1) bulk metals levels, (2) distribution in separated fractions, (3) size behavior in feeds and during processing, (4) speciation as a function of size, and (5) correlations with rheological properties. Some of the results of these studies show: (1) V and Ni have roughly bimodal size distributions, (2) groupings were seen based on location, size distribution, and Ni/V ratio of the sample, (3) Fe profiles are distinctively different, having a unimodal distribution with a maximum at relatively large molecular size, (4) Fe concentrations in the tar sand bitumens suggest possible fines solubilization in some cases, (5) SARA separated fractions show possible correlations of metals with asphaltene properties suggesting secondary and tertiary structure interactions, and (6) ICP-MS examination for soluble ultra-trace metal impurities show the possibility of unexpected elements such as U, Th, Mo, and others at concentrations in the ppB to ppM range. 39 refs., 13 figs., 5 tabs.

  17. Understanding AL-PAM assisted oil sands tailings treatment

    Energy Technology Data Exchange (ETDEWEB)

    Guo, L.; Maham, Y.; Masliyah, J.; Xu, Z. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering

    2010-07-01

    Technologies currently used to treat oil sands tailings include the composite tailings (CT) process and the thickened tailings (TT) or paste technology process. This PowerPoint presentation discussed a flocculation and filtration method used to produce stackable tailings deposits. Magnafloc 1011 and AL-PAM additions were used as part of the filtration technique to produce very dry filter cakes. The effect of AL-PAM molecular weight and aluminum content on tailings treatments was investigated as well as the effect of tailings characteristics on the performance of flocculant-assisted tailings filtration processes. The AL-PAM molecular structure was studied. An experimental study was conducted to determine the effect of various polymer additions on fresh tailings from an oil sands plant. The study showed that the optimum dosage for settling and filtration was lower for higher molecular weight AL-PAM. A higher aluminum content was beneficial for settling. Increases in the aluminum content did not improve filtration rates, but reduced optimal dosages. Step-by-step details of the supernatant filtration process were provided, as well as photographs of the laboratory study. tabs., figs.

  18. Oil sands tailings preliminary ecological risk assessment

    International Nuclear Information System (INIS)

    1994-01-01

    Chemical data collected from various oil sands soil-tailings mixtures were used to determine the ecological risk that such tailings would pose to terrestrial wildlife at the surface of a reclaimed site. A methodology that could be used to evaluate the risks posed by various reclamation options (for dry land only) was proposed. Risks associated with other reclamation options, such as wet landscapes or deeper in-pit disposal, were not evaluated. Ten constituents (eight organic and two inorganic) were found to pose a threat to terrestrial biota. The relative contribution of different exposure pathways (water and food ingestion, incidental soil ingestion, inhalation) were studied by probabilistic models. Some physical and chemical reclamation alternatives which involve incorporating oil sands tailings in the landscape to produce a surface that could sustain a productive ecosystem, were described. 53 refs., 15 tabs., 3 figs

  19. Characterization of oils sands thickened tailings

    Energy Technology Data Exchange (ETDEWEB)

    Scott, J.D.; Jeeravipoolvarn, S.; Donahue, R.; Ozum, B. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering

    2008-07-01

    This presentation discussed the characterization of oils sands thickened tailings. The problem statement was defined as the fact that many laboratory procedures to characterize fine tailings do not take into account the extraction process, and instead use standardized laboratory tests. The purpose of this presentation was to demonstrate how different extraction processes affect the fine tailings geotechnical properties and water chemistry. Properties that were characterized included particle size analysis from hydrometer-sieve tests; per cent clay from methylene blue tests; per cent clay from mineralogy tests; Atterberg limits; water chemistry; and morphology by scanning electron microscopy. The presentation discussed the origin of fines (silt and clay) in tailings; where fine particles come from; tailings materials; mineralogy of tailings; the hydrometer-sieve test on fine tailings and thickened tailings; and the methylene blue test. It was concluded that the great majority of clay minerals in the tailings come from the clay-shale discontinuous seams and layers. For thickened tailings, the dispersed and non-dispersed hydrometer tests show considerable difference in the amount of clay size material. tabs., figs.

  20. An investigation of the potential for in situ bioremediation of oil sands tailings

    International Nuclear Information System (INIS)

    Herman, D.C.; Costerton, J.W.; Fedorak, P.M.; Mackinnon, M.D.

    1993-01-01

    Oil sand tailings water has been shown to be acutely toxic to aquatic organisms. Naphthenic acids have been shown to be the primary source of this toxicity within oil sand tailings waste. The potential for in-situ bioremediation of oil sand tailings was investigated by determining the ability of indigenous bacteria to biodegrade naphthenic acids. A mixed bacterial culture enriched from oil sand tailings was found to be capable of growth on a commercially available naphthenic acid mixture. When sodium naphthenates (30 mg/l) were added to a minimal salts medium and inoculated with the mixed bacterial culture, gas chromatography revealed that many components of the naphthenic acid mixture were biodegraded within eight days of incubation. The same culture was also tested against the naphthenic acid fraction extracted directly from oil sand tailings. The tailings extract was diluted into the minimal salts medium in sealed flasks and inoculated with the enrichment culture. The production of CO 2 indicated microbial mineralization of components within the oil sands extract. Microtox analysis determined that microbial activity resulted in a reduction in the acute toxicity of the tailings extract. 5 refs., 3 figs

  1. Ilmenite Mineral's Recovery from Beach Sand Tailings

    International Nuclear Information System (INIS)

    Mulaba-Bafubiandi, Antoine F.; Mukendi-Ngalula, David; Waanders, Frans B.

    2002-01-01

    The mineral ilmenite is the major source of rutile for industrial use and is of interest to paint and fertiliser industries. Enormous unutilised tailing dams lie on the eastern coast of the South Africa. Although covered by a simulation of the original indigenous vegetation, these tailings are still ilmenite bearing and of economic value. Tailings emanating from beach sand mineral slimes dams of the Kwazulu-Natal area (South Africa) have been processed. Screening, flotation, spiral concentration and magnetic separation methods were used either separately or successively. The present work sheds light on alternative routes for the extraction of the ilmenite, from these tailings. It moreover points out the usefulness of the Moessbauer spectroscopy in the mineral processing product monitoring. Tailings from the beach sands were used in the present study after the economic industrial minerals zirconia, ilmenite and rutile had been extracted in previous mining operations. About 61% natural ilmenite recovery was observed in the flotation concentrate of a Humphrey Spiral concentrate while a 62% recovery of hematite was found in the flotation tailings. The combination of screening, spiral concentration and magnetic separation, and flotation yielded a product with the highest ilmenite and hematite concentration being 71% and 19%, respectively. A natural ilmenite mineral, containing 87% ilmenite and 13% hematite, could be produced and extracted from the tailings of the flotation process, collected subsequently to the spiral concentration and the initial screening.

  2. Phytoremediation of Alberta oil sand tailings using native plants and fungal endophytes

    Science.gov (United States)

    Repas, T.; Germida, J.; Kaminskyj, S.

    2012-04-01

    Fungal endophytes colonize host plants without causing disease. Some endophytes confer plant tolerance to harsh environments. One such endophyte, Trichoderma harzianum strain TSTh20-1, was isolated from a plant growing on Athabasca oil sand tailings. Tailing sands are a high volume waste product from oil sand extraction that the industry is required to remediate. Tailing sands are low in organic carbon and mineral nutrients, and are hydrophobic due to residual polyaromatic hydrocarbons. Typically, tailing sands are remediated by planting young trees in large quantities of mulch plus mineral fertilizer, which is costly and labour intensive. In greenhouse trials, TSTh20-1 supports growth of tomato seedlings on tailing sands without fertilizer. The potential use of TSTh20-1 in combination with native grasses and forbs to remediate under field conditions is being assessed. Twenty-three commercially available plant species are being screened for seed germination and growth on tailing sands in the presence of TSTh20-1. The best candidates from this group will be used in greenhouse and small scale field trials. Potential mechanisms that contribute to endophyte-induced plant growth promotion, such as plant hormone production, stress tolerance, mineral solubilization, and uptake are also being assessed. As well, TSTh20-1 appears to be remarkably frugal in its nutrient requirements and the possibility that this attribute is characteristic of other plant-fungal endophytes from harsh environments is under study.

  3. Pan Am tar sand bid revealed

    Energy Technology Data Exchange (ETDEWEB)

    Gray, E

    1968-12-16

    Muskeg Oil Co., wholly-owned subsidiary of Pan American Canada Oil Co. Ltd., hopes to expand its proposed initial 8,000 bpd in situ Athabasca tar sand production scheme to an ultimate rate of 60,000 bpd. The Muskeg recovery process involves an in situ combustion technique developed by Pan American and applied successfully in experimental work in the Athabasca area. The underground burning process develops heat in the formation, reduces crude bitumen viscosity, and displaces the bitumen to the producing wells. Core analyses have been used to determine bitumen in place, wherever possible. Values for uncored wells were based on logs, through development of an empirical relationship between formation resistivity measured by focused logging devices and bitumen content determined by core analysis. The proposed recovery process is a 10-acre well spacing with 9-spot configuration. The McMurray Formation will be fractured hydraulically and preheated by a combustion process. The bitumen will be recovered by a combustion displacement process utilizing air and water.

  4. Recent advancements in the geotechnical characterization of oil sands tailings

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, J. [Conetec, Richmond, BC (Canada)

    2010-07-01

    The technical aspects of soft oil sands tailings in-situ geotechnical site investigations were discussed. Geotechnical studies are conducted to determine containment structure stability as well as to determine volumetric and mass balances. The results of the studies are used in tailings management plans and construction activities. Flow penetrometers, field vane shear tests, and Gamma-CPTu tests are used in in-situ oil sands tailings geotechnical studies in order to determine pore pressure dissipation, and measure shear strength. Ball penetration tests are conducted to determine tailings strength. Methods of interpreting data from the tests were presented, and data from the tests were also compared and evaluated. Recommended procedures for strength screening were presented. Statistical methods for determining tailings behaviour types were outlined. The study showed that Gamma-CPTu data can be used to obtain reasonable preliminary estimates of solids and fines when combined with tailings behaviour type analyses. tabs., figs.

  5. Cemented Backfilling Technology of Paste-Like Based on Aeolian Sand and Tailings

    Directory of Open Access Journals (Sweden)

    Qinli Zhang

    2016-12-01

    Full Text Available Aeolian sand, tailings, and #32.5 Portland cement were used to produce backfilling aggregate, and physicochemical evaluations and proportioning tests were conducted. It is revealed that a mixture of aeolian sand and tailings can be used as a backfilling aggregate for the complementarities of their physicochemical properties; e.g., high Al2O3 content in the aeolian sand and CaO content in the tailings, coarse particles of aeolian sand and fine particles of tailings, etc. In addition, the optimal backfilling aggregate was shown to have a mass fraction of 72%–74%, a cement–sand ratio of 1:8, and an aeolian sand proportion of 25%. Furthermore, viscometer tests were used to analyze the rheological characteristics, and the slurry in these optimized proportions exhibited shear thinning phenomena with an initial yield stress, which belongs to paste-like—a cemented backfilling slurry with a higher mass fraction than a two-phase flow and better flowability than a paste slurry. Finally, the application of this backfilling technology shows that it can not only realize safe mining, but also bring huge economic benefits, and has some constructive guidance for environmental protection.

  6. Naphtha evaporation from oil sands tailings ponds

    Energy Technology Data Exchange (ETDEWEB)

    Kasperski, K.; Munoz, V.; Mikula, R. [Natural Resources Canada, Devon, AB (Canada). CANMET Western Research Centre

    2010-07-01

    The environmental impacts of volatile organic compounds (VOCs) from oil sands tailings ponds must be considered when evaluating new oil sands mining and extraction operations. Studies have suggested that only 40 percent of the solvent sent to tailings ponds is available to the environment, while the rest is irreversibly trapped. The recovery of hydrocarbons from oil sands froth process water is low. This PowerPoint presentation discussed a method of distinguishing between water and hydrocarbons at low temperatures. Samples were heated to 246 degrees C at 15 degrees C and held for 10 minutes. Heating was then resumed at 750 degrees C and held for 10 minutes in a pyrolysis phase, then cooled and reheated with an oxygen addition. The method demonstrated that the diluent distribution between the solids and water phases is misinterpreted as diluent that will evaporate, and diluent that will not evaporate. The study concluded by suggesting that the definition of recoverable and unrecoverable hydrocarbon should be re-termed as easily recoverable, and difficult to recover. tabs., figs.

  7. Economic and environmental effects of the FQD on crude oil production from tar sands

    Energy Technology Data Exchange (ETDEWEB)

    Kampman, B.; De Buck, A.; Afman, M. [CE Delft, Delft (Netherlands); Van den Berg, J.; Otten, G.J. [Carbon Matters, Den Haag (Netherlands)

    2013-05-15

    The production of unconventional crudes in Canada and Venezuela and exports of these crudes to the EU are investigated. In addition the potential economic and environmental impact of the proposed EU FQD measures (Fuel Quality Directive) on the production of crudes from tar sands and on new tar sand exploration projects are examined. CE Delft has analysed the impact by using a dedicated cost model. For existing projects, the model determines the effect on the basis of marginal production costs. For planned projects the model used the net present value (NPV) of proposed investments. The impacts were determined for a range of crude oil prices and FQD price effects. Combined, for existing and new projects together, the maximum effect would be at a price level at 60 USD/bbl, with savings of up to 19 Mt CO2/y at an FQD price differential of 3 euro/bbl. This overall effect would be substantial and come on top of the total emission reduction effect of the FQD of 60 Mt CO2/y, which will be achieved mostly by the blending of low-carbon fuels and reduced flaring and venting. As part of the reduction of transport greenhouse gas (GHG) emissions, the revised FQD obliges fuel suppliers to reduce these emissions by 6% by 2020 on a well-to-wheel basis. The EU is currently developing a methodology to differentiate fossil fuels on the basis of feedstock and GHG emissions. In the proposal, diesel produced from tar sands, has been given a default emission value of 108.5 gCO2 eq/MJ, while diesel from conventional crude was set at 89.1 gCO2 eq/MJ. The Commission's proposal is currently undergoing an impact assessment and is expected to be resubmitted to the Council later this year (2013)

  8. Predicting development of undrained shear strength in soft oil sands tailings

    Energy Technology Data Exchange (ETDEWEB)

    Masala, S. [Klohn Crippen Berger, Calgary, AB (Canada); Matthews, J. [Shell Canada Ltd., Calgary, AB (Canada)

    2010-07-01

    This PowerPoint presentation discussed a method of predicting the development of undrained shear strength in soft oil sands tailings. Phenomenology charts of oil sands tailings ponds were used to present the suspension, density, stresses and hydrostatic behaviour of tailings. Sedimentation and consolidation processes were discussed. The charts demonstrated how the tailings slurry settles and consolidates, releases water and dissipates pore pressures. The slurry then develops intergranular stresses and increases in density. The increases correlate with increased resistance to deformation and decreased compressibility and hydraulic conductivity. A critical state soil mechanics (CSSM) was used to characterize the soft oil sands tailings. Undrained strength was determined using the concept of the undrained strength ratio (USR). The USR was determined using traditional geotechnical investigation methods. Settling of the non-consolidated (NC) soil deposits was simulated using the finite strain consolidation theory. The model was based on the premise that current effective stresses control undrained shear strength in the NC deposits. Case studies were used to demonstrate the predictive framework. tabs, figs.

  9. Oil sands tailings technology : understanding the impact to reclamation

    Energy Technology Data Exchange (ETDEWEB)

    Mamer, M. [Suncor Energy Inc., Fort McMurray, AB (Canada)

    2010-07-01

    This paper discussed tailings management techniques at oil sands mines and their effects on reclamation schedules and outcomes. The layer of mature fine tailings (MFT) that forms in tailings ponds does not settle within a reasonable time frame, requiring more and larger tailings ponds for storing MFT. Consolidated tailings (CT) technology was developed to accelerate the consolidation of MFT, although the process nonetheless takes decades. CT is produced from mixing tailings sand, gypsum, and MFT to create a mixture that will consolidate more quickly and release water. However, CT production is tied to the extraction process, making it applicable only when the plant is operational, and a precise recipe and accurate injection are required for CT to work. In tailings reduction operations (TRO), a new approach to tailings management, MFT is mixed with a polymer flocculant, deposited in thin layers, and allowed to dry. TRO has a significant advantage over CT in that the latter takes up to 30 years to consolidate to a trafficable surface compared to weeks for TRO. TRO allows MFT to be consumed more quickly than it is produced, reducing need to build more tailings ponds, operates independent of plant operations, accelerates the reclamation time frame, and offers enhanced flexibility in final tailings placement sites. TRO also creates a dry landscape, to which well established reclamation techniques can be applied. Dried MFT is a new material type, and research is exploring optimum reclamation techniques. 2 figs.

  10. Tar sand extraction by steam stimulation and steam drive: measurement of physical properties

    Energy Technology Data Exchange (ETDEWEB)

    Linberg, W.R.

    1980-09-10

    The measurement of the following thermophysical properties of Utah tar sands is in progress: thermal conductivity, specific heat relative permeability, and viscosity (of the recovered bitumen). During the report period (October 1, 1978 to November 1, 1979), experimental procedures have been developed and a basic data set has been measured. Additionally, standard core analysis has been performed for four drill sites in the Asphalt Ridge, Utah area.

  11. Oil sands tailings treatment via surface modification of solids with polymers

    Energy Technology Data Exchange (ETDEWEB)

    Soane, D.; Ware, W.; Mahoney, R.; Kincaid, K. [Soane Energy, Cambridge, MA (United States)

    2010-07-01

    Oil sands fine tailings require large containment area and long-term storage. A recent directive has been established to reduce fluid tailings storage by 30 percent by 2012. This PowerPoint presentation described a method of treating oil sands tailings by modifying the surfaces of solids with polymers. The ATA process divided whole tailings into fines and coarse streams. The coarse stream was used to prepare anchor particles with a monolayer of tether polymers. An activator was added to the fine tailings in order to aggregate. The process cause a Velcro-like attraction between the activated fines and the tether-coated anchor particles. The solid ATA matrix trapped the fines and allowed water to drain more easily. Photographs of the process were provided. An analysis of the process demonstrated that 70 percent of the water in the tailings was recovered in less than 5 minutes. The water was clear, with less than 0.2 percent of suspended solids. The process is applicable to live tailings and mature fine tailings (MFT). tabs., figs.

  12. Cashing in on Tar Sands. RBS, UK banks and Canada's 'blood oil'

    Energy Technology Data Exchange (ETDEWEB)

    Evans, M.; Howarth, C.; Kellay, A.; Laboucan, B.J.; Mercredi, M.; Minio-Paluelo, M.; Schling, H.; Smith, K.; Thomas-Muller, C.; Wood, A.

    2010-03-15

    Tar sands extraction in Canada is devastating Indigenous communities, wildlife and vast areas of boreal forests, as well as being many times more carbon-intensive to produce than 'conventional' oil. The higher oil prices in recent years have meant that it's become a more attractive prospect for oil companies to expand their operations in the costly process of obtaining and processing the thick bitumen into a usable form. It's estimated that the industry is looking for a capital investment of 120-220 billion USD over the next 20 years to build the new pipelines, mines, refineries and upgraders that are necessary to sustain the boom. This report looks at the role that UK banks are playing in providing the necessary capital, and how RBS (Royal Bank of Scotland), which is 84% owned by the UK public, has been the bank the most heavily involved in underwriting loans to companies engaging in tar sands extraction.

  13. Polymer aids for settling and filtration of oil sands tailings

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering; Energy Resources Conservation Board, Calgary, AB (Canada). Oil Sands Section; Xu, Z.; Masliyah, J.H. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering

    2008-07-01

    Oil sand tailings are segregated into coarse and fine tailings. High volumes of toxic fluids and tailings are created in the process. Tailings ponds are an environmental risk with high operating and maintenance costs. Current commercial technologies uses chemical additions to create recycled water and composite tailings (CT). Researchers are now investigating centrifuged and dry mature fine tailings (MFT). Filtration processes with flocculants are used to separate the tailings into warm recycle water and dried cakes that can be used in reclamation processes. Studies are being conducted to find a polymer than can effectively flocculate and filter whole oil sands tailings. The filtration procedure uses pressure to produce released water. Polymers include magnafloc and Al-PAM polymer concentrations are used in slurry masses. Tests have been conducted to determine the settling rates of the polymers. The tests showed that Al-PAM filtered the tailings effectively. Paraffinic froth treatment tests have also been conducted to determine settling rates. A cake produced with froth treatment tailings of Al-PAM 400 ppm had a water content 42.5 wt per cent. The tests showed that while Magnafloc 1011 is a good settling aid, but a poor filtration addition. Al-PAM aided in both the flocculation and filtration processes. Higher Al-PAM dosages are needed for froth treatment tailings processes. It was concluded that dry cakes are produced with the addition of Al-PAM. tabs., figs.

  14. Mud-farming of fine oil sands tailings

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Y.; Tol van, F.; Paassen van, L.; Everts, B.; Mulder, A. [Delft Univ. of Technology, Delft (Netherlands). Dept. of Geotechnology

    2010-07-01

    This PowerPoint presentation discussed an experimental mud-farming technique for fine oil sands tailings. The technique was based on a sub-areal drying technique for dredging sludge developed in the Netherlands for Rotterdam harbour sediments. Between 1960 and 1985, the sludge was deposited in confined disposal sites on land. The sludge was converted to usable clay between 1970 and 1980. The polluted portion of the sludge is stored in a man-made disposal site. The sludge was deposited in thin layers. Stagnant water was then removed. The mud was then dewatered and reused. The sludge was furrowed with amphirol and disc wheels in order to accelerate the ripening process. The dredged material was re-used in a clay factory. The technique was applied to oil sands tailings in order to understand the suction behaviour, sedimentation behaviour, and precipitation deficit of the tailings. State changes of the sludge were monitored. No clear sedimentation phase was identified prior to consolidation. A comparison of material properties showed that the total amount of water to be extracted was more than the Rotterdam sludge, but the suction behaviour was similar. The precipitation deficit from mid-April until September will require a customized deposition strategy. Details and photographs of the experimental studies were included. tabs., figs.

  15. Microbial communities involved in methane production from hydrocarbons in oil sands tailings.

    Science.gov (United States)

    Siddique, Tariq; Penner, Tara; Klassen, Jonathan; Nesbø, Camilla; Foght, Julia M

    2012-09-04

    Microbial metabolism of residual hydrocarbons, primarily short-chain n-alkanes and certain monoaromatic hydrocarbons, in oil sands tailings ponds produces large volumes of CH(4) in situ. We characterized the microbial communities involved in methanogenic biodegradation of whole naphtha (a bitumen extraction solvent) and its short-chain n-alkane (C(6)-C(10)) and BTEX (benzene, toluene, ethylbenzene, and xylenes) components using primary enrichment cultures derived from oil sands tailings. Clone libraries of bacterial 16S rRNA genes amplified from these enrichments showed increased proportions of two orders of Bacteria: Clostridiales and Syntrophobacterales, with Desulfotomaculum and Syntrophus/Smithella as the closest named relatives, respectively. In parallel archaeal clone libraries, sequences affiliated with cultivated acetoclastic methanogens (Methanosaetaceae) were enriched in cultures amended with n-alkanes, whereas hydrogenotrophic methanogens (Methanomicrobiales) were enriched with BTEX. Naphtha-amended cultures harbored a blend of these two archaeal communities. The results imply syntrophic oxidation of hydrocarbons in oil sands tailings, with the activities of different carbon flow pathways to CH(4) being influenced by the primary hydrocarbon substrate. These results have implications for predicting greenhouse gas emissions from oil sands tailings repositories.

  16. Meeting the challenge - solutions for managing oil sands tailings: report of the fine tailings fundamentals consortium 1989-1995

    International Nuclear Information System (INIS)

    1996-01-01

    The development and demonstration of effective alternatives for the management of fine tailings in the oil sands industry were discussed in a report describing the work of the Fine Tailings Fundamentals Consortium during the period from 1989 to 1995. The final report of the Consortium is a four-volume publication entitled 'Advances in Oil Sands Tailings Research' which is the state-of-the-art reference to key issues in the reclamation of fine tailings. Government regulations now make it the responsibility of industry to integrate the fine tailings into reclaimed landscapes, so that the final landscape is equal in productive capability to the pre-disturbed state. Impressive progress has been made in understanding the formation of fine tailings and in characterizing their properties, much of it through the work of this Consortium. Fundamental research on the clay particles within fine tailings provides a better understanding of how to manage them. Although there is no 'magic bullet', research has demonstrated that an integrated approach incorporating fine tailings with a variety of elements, uplands, lakes and wetlands, offer the best hope for an environmentally sound solution. figs

  17. Co-occurrence of methanogenesis and N{sub 2} fixation in oil sands tailings

    Energy Technology Data Exchange (ETDEWEB)

    Collins, C.E. Victoria [Department of Renewable Resources, University of Alberta, Edmonton, AB T6G 2G7 (Canada); Foght, Julia M. [Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9 (Canada); Siddique, Tariq, E-mail: tariq.siddique@ualberta.ca [Department of Renewable Resources, University of Alberta, Edmonton, AB T6G 2G7 (Canada)

    2016-09-15

    Oil sands tailings ponds in northern Alberta, Canada have been producing biogenic gases via microbial metabolism of hydrocarbons for decades. Persistent methanogenic activity in tailings ponds without any known replenishment of nutrients such as fixed nitrogen (N) persuaded us to investigate whether N{sub 2} fixation or polyacrylamide (PAM; used as a tailings flocculant) could serve as N sources. Cultures comprising mature fine tailings (MFT) plus methanogenic medium supplemented with or deficient in fixed N were incubated under an N{sub 2} headspace. Some cultures were further amended with citrate, which is used in oil sands processing, as a relevant carbon source, and/or with PAM. After an initial delay, N-deficient cultures with or without PAM produced methane (CH{sub 4}) at the same rate as N-containing cultures, indicating a mechanism of overcoming apparent N-deficiency. Acetylene reduction and {sup 15}N{sub 2} incorporation in all N-deficient cultures (with or without PAM) suggested active N{sub 2} fixation concurrently with methanogenesis but inability to use PAM as a N source. 16S rRNA gene pyrosequencing revealed little difference between archaeal populations regardless of N content. However, bacterial sequences in N-deficient cultures showed enrichment of Hyphomicrobiaceae and Clostridium members that might contain N{sub 2}-fixing species. The results are important in understanding long-term production of biogenic greenhouse gases in oil sands tailings. - Highlights: • Methanogenesis in oil sands tailings can occur under nitrogen depleted conditions. • {sup 15}N{sub 2} isotopic analysis reveals that indigenous microbes can fix N{sub 2} for microbial metabolism and methanogenesis. • 16S rRNA gene analysis suggests that members of Hyphomicrobiaceae and Clostridium may be involved in N{sub 2} fixation. • This is the first report that describes co-occurrence of methanogenesis and nitrogen fixation in oil sands tailings.

  18. Sulfur biogeochemistry of oil sands composite tailings

    Energy Technology Data Exchange (ETDEWEB)

    Warren, Lesley; Stephenson, Kate [Earth Sciences, McMaster University (Canada)], email: warrenl@mcmaster.ca; Penner, Tara [Syncrude Environmental Research (Canada)

    2011-07-01

    This paper discusses the sulfur biogeochemistry of oil sands composite tailings (CT). The Government of Alberta is accelerating reclamation activities on composite tailings. As a CT pilot reclamation operation, Syncrude is currently constructing the first freshwater fen. Minor unpredicted incidents with H2S gas released from the dewatering process associated with these reclamations have been reported. The objective of this study is to ascertain the connection between microbial activity and H2S generation within CT and to assess the sulfur biogeochemistry of untreated and treated (fen) CT over seasonal and annual timescales. The microbial geochemical interactions taking place are shown using a flow chart. CT is composed of gypsum, sand, clay and organics like naphthenic acids and bitumen. Sulfur and Fe cycling in mining systems and their microbial activities are presented. The chemistry and the processes involved within CT are also given along with the results. It can be said that the diverse Fe and S metabolizing microorganisms confirm the ecology involved in H2S dynamics.

  19. Microbially-accelerated consolidation of oil sands tailings. Pathway I: changes in porewater chemistry.

    Science.gov (United States)

    Siddique, Tariq; Kuznetsov, Petr; Kuznetsova, Alsu; Arkell, Nicholas; Young, Rozlyn; Li, Carmen; Guigard, Selma; Underwood, Eleisha; Foght, Julia M

    2014-01-01

    Dispersed clay particles in mine tailings and soft sediments remain suspended for decades, hindering consolidation and challenging effective management of these aqueous slurries. Current geotechnical engineering models of self-weight consolidation of tailings do not consider microbial contribution to sediment behavior, however, here we show that microorganisms indigenous to oil sands tailings change the porewater chemistry and accelerate consolidation of oil sands tailings. A companion paper describes the role of microbes in alteration of clay chemistry in tailings. Microbial metabolism in mature fine tailings (MFT) amended with an organic substrate (hydrolyzed canola meal) produced methane (CH4) and carbon dioxide (CO2). Dissolution of biogenic CO2 lowered the pH of amended MFT to pH 6.4 vs. unamended MFT (pH 7.7). About 12% more porewater was recovered from amended than unamended MFT during 2 months of active microbial metabolism, concomitant with consolidation of tailings. The lower pH in amended MFT dissolved carbonate minerals, thereby releasing divalent cations including calcium (Ca(2+)) and magnesium (Mg(2+)) and increasing bicarbonate (HCO(-) 3) in porewater. The higher concentrations increased the ionic strength of the porewater, in turn reducing the thickness of the diffuse double layer (DDL) of clay particles by reducing the surface charge potential (repulsive forces) of the clay particles. The combination of these processes accelerated consolidation of oil sands tailings. In addition, ebullition of biogenic gases created transient physical channels for release of porewater. In contrast, saturating the MFT with non-biogenic CO2 had little effect on consolidation. These results have significant implications for management and reclamation of oil sands tailings ponds and broad importance in anaerobic environments such as contaminated harbors and estuaries containing soft sediments rich in clays and organics.

  20. Continued studies of soil improvement and revegetation of tailings sand slopes. Environmental Research Monograph 1977-4

    Energy Technology Data Exchange (ETDEWEB)

    Rowell, M J

    1977-01-01

    Fertilizer studies continued on a 5-year old revegetated area on a tailings sand dike in the Athabasca Tar Sands area. In June 1976 levels of available N, P, K, and S were adequate for plant growth. However, even where fertilizers were added levels of mineral N had dropped to low levels by September. Plant top production early in the 1976 season was increased by application of nitrogen fertilizer during the previous August. Erosion of the area was negligible in 1976. In the new revegetation experiments on steep tailings and slopes, erosion could be minimized by the rapid establishment of a plant cover. Nutrient losses in surface water runoff amounted to a maximum of only 2.6 kg N, 0.4 kg P, 4.1 kg K and 3.4 kg S/ha in the treatments studied. Water infiltration into the dike was rapid and varied between 24.0 and 30.5 cm/h. Estimates suggested that between 13 and 34% of the intercepted rainfall leached below the 30 cm depth while plants were being established during the first year of growth. Estimates of nutrient losses below the root zone (30 cm) ranged between 1.3 and 31.2 kg N/ha; <0.1 kg P/ha; 1.1 and 10.1 kg K/ha and 4.8 to 38.1 kg S/ha in the different treatments studied. The seed mix used contained oats as a nurse crop and 9 grass and 4 legume species. Plant growth was adequate to protect the soil surface from serious erosion. The dry weight production by the oats was considerably greater than for either the grasses or legumes. The cover produced by grasses and legumes alone would have been adequate in terms of erosion control except in those treatments involving heavy applications of mine overburdens. The dry weight production of root and shoot tissues was about the same. Root growth was largely restricted to the surface 15 cm. Total numbers of bacteria, fungi and actinomycetes as well as total soil respiration was considerably greater in soils from the revegetation experiments in comparison to samples of fresh or weathered tailings sand.

  1. Methanogenic biodegradation of paraffinic solvent hydrocarbons in two different oil sands tailings.

    Science.gov (United States)

    Mohamad Shahimin, Mohd Faidz; Siddique, Tariq

    2017-04-01

    Microbial communities drive many biogeochemical processes in oil sands tailings and cause greenhouse gas emissions from tailings ponds. Paraffinic solvent (primarily C 5 -C 6 ; n- and iso-alkanes) is used by some oil sands companies to aid bitumen extraction from oil sands ores. Residues of unrecovered solvent escape to tailings ponds during tailings deposition and sustain microbial metabolism. To investigate biodegradation of hydrocarbons in paraffinic solvent, mature fine tailings (MFT) collected from Albian and CNRL ponds were amended with paraffinic solvent at ~0.1wt% (final concentration: ~1000mgL -1 ) and incubated under methanogenic conditions for ~1600d. Albian and CNRL MFTs exhibited ~400 and ~800d lag phases, respectively after which n-alkanes (n-pentane and n-hexane) in the solvent were preferentially metabolized to methane over iso-alkanes in both MFTs. Among iso-alkanes, only 2-methylpentane was completely biodegraded whereas 2-methylbutane and 3-methylpentane were partially biodegraded probably through cometabolism. 16S rRNA gene pyrosequencing showed dominance of Anaerolineaceae and Methanosaetaceae in Albian MFT and Peptococcaceae and co-domination of "Candidatus Methanoregula" and Methanosaetaceae in CNRL MFT bacterial and archaeal communities, respectively, during active biodegradation of paraffinic solvent. The results are important for developing future strategies for tailings reclamation and management of greenhouse gas emissions. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. The effect of oil sands tailings pond sediments on embryo-larval walleye (Sander vitreus).

    Science.gov (United States)

    Raine, J C; Turcotte, D; Tumber, V; Peru, K M; Wang, Z; Yang, C; Headley, J V; Parrott, J L

    2017-10-01

    Walleye (Sander vitreus) are a commercially important North American fish species that inhabit the Athabasca River. This river flows through the Athabasca oil sands where natural sources of bitumen erode from the McMurray formation. Little information is available on responses of walleye embryos to oil sands tailings pond sediments in a laboratory setting. The current study describes the design and implementation of a daily-renewal bioassay to assess the potential effects of tailings pond sediments from the Athabasca oil sands area on walleye development. Developing walleye embryos were exposed to increasing concentrations of two tailings pond sediments (collected in the Athabasca oil sands area) until the completion of yolk absorption in control fish. Sediments from the tailings pond represent a mixture of polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs. During the 31 day exposure, the walleye were examined for mortalities, weight, length and developmental abnormalities to provide an initial evaluation of the effects of the oil sands tailings pond sediments. Walleye embryo survival differed between the tailings pond sediments, and survival decreased with increasing sediment concentration. Alkylated PAH content differed between the two tailings pond sediments and lower embryo survival corresponded to higher total and alkylated PAH content. Tailings pond sediment-exposed walleye exhibited a delay in development, as well as increased percentages of larvae with heart and yolk sac edema, and cranial and spinal malformations. These abnormalities in development are often associated with PAH and alkylated PAH exposure. This study provides an exposure design that can be used to assess sediment toxicity to early developmental stages of a fish species not commonly tested in the lab, and lays the groundwork for future studies with this and other difficult-to-culture species. These results offer information on the potential effects of tailings pond sediments

  3. Mature fine tailings from oil sands processing harbour diverse methanogenic communities

    Energy Technology Data Exchange (ETDEWEB)

    Penner, T.J.; Foght, J.M. [Alberta Univ., Edmonton, AB (Canada). Dept. of Biological Sciences

    2010-06-15

    Syncrude's bitumen extraction process produces a fine tailings slurry consisting of water, sand, fines, residual bitumen and naphtha diluent. Following rapid settling of the sand fraction, the tailings are stored in large settling ponds to form a thick mature fine tailings (MFT). This paper discussed the potential benefits of methane production on management of the settling basins. Enhanced methanogenesis accelerates densification and improves the rheological properties of MFT. In this study molecular techniques were used to characterize the methanogenic communities in uncultivated MFT samples to determine the diversity present in the Mildred Lake Settling Basin (MLSB) and West In-Pit tailings deposit. The flux of methane is currently estimated at about 40 million L/day at the MLSB. Clone libraries of amplified archaeal and bacterial 16S rRNA genes were created in order to analyze the methanogenic consortia in MFT samples from depth profiles in the 2 tailings deposits. The archaeal sequences, whose closest matches were primarily cultivated methanogens, were comparable within and between basins and were mostly affiliated with acetoclastic Methanosaeta spp. However, bacterial clone libraries were diverse, with most sequences relating to Proteobacteria, including some presumptive nitrate-, iron-, or sulfate-reducing, hydrocarbon-degrading genera. The study showed that MFT consists of a diverse community of prokaryotes that may be responsible for producing methane from substrates indigenous to the MFT. These findings contribute to a better understanding of the biogenesis of methane and densification of MFT in oil sands tailings deposits. The results from this study will help determine strategies to control and exploit microbial activities in these large systems and improve the understanding of methanogenic environments. 43 refs., 2 tabs., 3 figs.

  4. 1170-MW(t) HTGR-PS/C plant application study report: tar sands oil recovery application

    International Nuclear Information System (INIS)

    Rao, R.; McMain, A.T. Jr.

    1981-05-01

    This report summarizes a study to apply an 1170-MW(t) high-temperature gas-cooled reactor - process steam/cogeneration (HTGR-PS/C) to tar sands oil recovery and upgrading. The raw product recovered from the sands is a heavy, sour bitumen; upgrading, which involves coking and hydrodesulfurization, produces a synthetic crude (refinable by current technology) and petroleum coke. Steam and electric power are required for the recovery and upgrading process. Proposed and commercial plants would purchase electric power from local utilities and obtain from boilers fired with coal and with by-product fuels produced by the upgrading. This study shows that an HTGR-PS/C represents a more economical source of steam and electric power

  5. Co-occurrence of methanogenesis and N2 fixation in oil sands tailings.

    Science.gov (United States)

    Collins, C E Victoria; Foght, Julia M; Siddique, Tariq

    2016-09-15

    Oil sands tailings ponds in northern Alberta, Canada have been producing biogenic gases via microbial metabolism of hydrocarbons for decades. Persistent methanogenic activity in tailings ponds without any known replenishment of nutrients such as fixed nitrogen (N) persuaded us to investigate whether N2 fixation or polyacrylamide (PAM; used as a tailings flocculant) could serve as N sources. Cultures comprising mature fine tailings (MFT) plus methanogenic medium supplemented with or deficient in fixed N were incubated under an N2 headspace. Some cultures were further amended with citrate, which is used in oil sands processing, as a relevant carbon source, and/or with PAM. After an initial delay, N-deficient cultures with or without PAM produced methane (CH4) at the same rate as N-containing cultures, indicating a mechanism of overcoming apparent N-deficiency. Acetylene reduction and (15)N2 incorporation in all N-deficient cultures (with or without PAM) suggested active N2 fixation concurrently with methanogenesis but inability to use PAM as a N source. 16S rRNA gene pyrosequencing revealed little difference between archaeal populations regardless of N content. However, bacterial sequences in N-deficient cultures showed enrichment of Hyphomicrobiaceae and Clostridium members that might contain N2-fixing species. The results are important in understanding long-term production of biogenic greenhouse gases in oil sands tailings. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Tailings dewatering in the oil sands

    Energy Technology Data Exchange (ETDEWEB)

    Longo, S.; Labelle, M. [Golder Paste Technology, Sudbury, ON (Canada); Wislesky, I. [Golder Associates Ltd., Calgary, AB (Canada)

    2010-07-01

    Alberta's Directive 074 was established to reduce fluid tailings produced during oil sands extraction processes. This PowerPoint presentation examined some of the dewatering strategies available for oil sands operators and provided recommendations for implementing a dewatering plan. Sites must be evaluated in order to determine their chemistry, mineralogy, and the total quantity of material to be handled. The availability of potential additives must also be considered. Process technologies must be selected in relation to the operator's depositional strategy. Each site will require its own unique dewatering and depositional strategy. Dewatering technologies include thickening; in-line flocculation; centrifuge; co-mingling; and various new technologies such as electro-osmosis. Laboratory testing programs include index tests, primary stream thickening, and mini-pilot plant testing. The performance of various testing formats was evaluated. Thickening and depositional techniques were reviewed. tabs., figs.

  7. Dewatering behavior of fine oil sands tailings : A summary of laboratory results

    NARCIS (Netherlands)

    Yao, Y.; van Tol, A.F.; van Paassen, L.A.; Vardon, P.J.; Sego, D.C.; Wilson, G.W.; Beier, N.A.

    2016-01-01

    To evaluate the disposal technology for fine oil sands tailings, the appropriate engineering properties of the tailings should be ascertained. A laboratory study was conducted by Delft University of Technology (the Netherlands) on the geotechnical properties and dewatering behavior of the fine oil

  8. Oil sands to the rescue: oil sand microbial communities can degrade recalcitrant alkyl phenyl alkanoic acids

    Energy Technology Data Exchange (ETDEWEB)

    Whitby, Corinne [University of Essex (Canada)], email: cwhitby@essex.ac.uk

    2011-07-01

    Almost half of all global oil reserves are found as biodegraded heavy oils found in vast tar sand deposits located in North and South America and these account for 47% of Canadian oil production. Oil sand extraction generates large amounts of toxic waste water, known as oil sand process waters (OSPW), that are stored in large tailing ponds that contain toxic compounds like naphthenic acids (NAs). The presence of NAs creates problems like toxicity, corrosion, and the formation of calcium napthenate deposits which block pipelines and other infrastructure and need to be removed. This paper presents oil sand microbial communities that can degrade these NAs. The approach is to apply new aliphatic and aromatic NAs as substrates to supplement and identify NA degrading microbes and also to identify the metabolites produced and explain NA degradation pathways and the functional genes involved. The chemistry and the processes involved are explained. From the results, it is suggested that pure cultures of P. putida KT2440 be used against NAs.

  9. Environmental survey - tar sands in situ processing research program (Vernal, Uintah County, Utah). [Reverse-forward combustion; steam injection

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, Q.

    1980-03-01

    Research will be done on the reverse-forward combustion and steam injection for the in-situ recovery of oil from tar sands. This environmental survey will serve as a guideline for the consideration of environmental consequences of such research. It covers the construction phase, operational phase, description of the environment, potential impacts and mitigations, coordination, and alternatives. (DLC)

  10. Advanced characterisation of organic matter in oil sands and tailings sands used for land reclamation by Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS)

    Science.gov (United States)

    Noah, M.; Vieth-Hillebrand, A.; Wilkes, H.

    2012-04-01

    The Athabasca region of northern Alberta, Canada, is home to deposits of oil sands containing vast amounts (~ 173 billion barrels) of heavily biodegraded petroleum. Oil sands are recovered by surface mining or by in situ steam injection. The extraction of bitumen from oil sands by caustic hot water processing results in large volumes of fluid tailings, which are stored in on-site settling basins. There the tailings undergo a compaction and dewatering process, producing a slowly densifying suspension. The released water is recycled for extraction. The fine tailings will be reclaimed as either dry or wet landscapes. [1] To produce 1 barrel of crude oil, 2 tons of oil sand and 2 - 3 tons of water (including recycled water) are required. [2] Open pit mining and the extraction of the bitumen from the oil sands create large and intense disturbances of different landscapes. The area currently disturbed by mining operations covers about 530 km2 and the area of tailing ponds surpasses 130 km2. An issue of increasing importance is the land remediation and reclamation of oil sand areas in Canada and the reconstruction of these disturbed landscapes back to working ecosystems similar to those existing prior to mining operations. An important issue in this context is the identification of oil sand-derived organic compounds in the tailings, their environmental behaviour and the resulting chances and limitations with respect to land reclamation. Furthermore the biodegradation processes that occur in the tailings and that could lead to a decrease in hazardous organic compounds are important challenges, which need to be investigated. This presentation will give a detailed overview of our compositional and quantitative characterisation of the organic matter in oil sand, unprocessed and processed mature fine tailings samples as well as in tailings sands used as part of land reclamation. The analytical characterisation is based on the extraction of the soluble organic matter, its

  11. Oil sands tailings leachability and toxicity evaluation

    International Nuclear Information System (INIS)

    Gulley, J.R.

    1995-01-01

    Fine tailings disposal and reclamation is a major issue facing the oil sands mining and extraction industry. Government regulations dictate that reclamation must return the site to a level of self-sustaining biological capability which approximates the natural condition. A two-phase laboratory program has been completed to investigate the suitability of alternative reclamation materials. For the first phase of the study, chemical and toxicological analyses were carried out on 13 different reclamation and reference materials (solid phase and extractions). Seedling emergence, nematode maturation, algal growth and bacterial luminescence for leachate samples showed a range of sensitivities in response to the tested materials, although phytotoxicity tests were generally the most sensitive. With the exception of one test material, high toxicity ratings were consistent with that expected from the chemical data. The second phase of the study focused on the evaluation of chemical and toxicological conditions in leachate water generated using bench-scale column percolation tests. Leachate water equivalent to 10 pore volume replacements was generated and temporal variations in toxicity and chemistry monitored. Similar to phase 1 findings, phytotoxicity tests were the most sensitive tests to leachate waters. For most materials tested, most toxicity was removed after 2--3 porewater replacements. More persistent toxicity was noted for samples containing bitumen (e.g., fine tails and oil sands). No clear correspondence was noted between chemical concentrations and toxicity in leachate waters

  12. Experimental research on accelerated consolidation using filter jackets in fine oil sands tailings

    Energy Technology Data Exchange (ETDEWEB)

    Tol van, F.; Yao, Y.; Paaseen van, L.; Everts, B. [Delft Univ. of Technology, Delft (Netherlands). Dept. of Geotechnology

    2010-07-01

    This PowerPoint presentation discussed prefabricated vertical drains used to enhance the dewatering of fine oil sand tailings. Filtration tests conducted with thickened tailings on standard PVD jackets were presented. Potential clogging mechanisms included clogging of the filter jacket by particles, blinding of the jackets by filter cake, the decreased permeability of consolidated tailings around the drain, and the clogging of the filter jacket with bitumen. Polypropylene and polyester geotextiles were tested in a set-up that replicated conditions observed at 5 to 10 meters below mud level in an oil sand tailings pond. A finite strain consolidation model was used to interpret results obtained in the experimental study. The relationship between the void ratio and hydraulic conductivity was investigated. Results of the study showed that neither the bitumen nor the fines in the sludge cause serious blinding of the filter jackets during the 40 day test period. The consolidation process was adequately simulated with the finite strain consolidation model. tabs., figs.

  13. White sand potentially suppresses radon emission from uranium tailings

    Science.gov (United States)

    Abdel Ghany, H. A.; El Aassy, Ibrahim E.; Ibrahim, Eman M.; Gamil, S. H.

    2018-03-01

    Uranium tailings represent a huge radioactive waste contaminant, where radon emanation is considered a major health hazard. Many trials have been conducted to minimize radon exhalation rate by using different covering materials. In the present work, three covering materials, commonly available in the local environment, (kaolin, white sand and bentonite) have been used with different thickness 10, 15, and 20 mm). 238U, 232Th, 40K and the radon exhalation rate were measured by using gamma spectrometry with a Hyper Pure Germanium (HPGe) detector and solid state nuclear track detectors (CR-39). Radon exhalation rate, calculated before and after covering, ranged from 2.80 ± 0.14 to 4.20 ± 0.21 Bq m-2 h-1, and from 0.30 ± 0.01 to 4.00 ± 0.20 Bq m-2 h-1, respectively. Also, the attenuation coefficients of different covering materials and radon emanation were calculated. The obtained results demonstrate that covering of uranium tailings by kaolin, white sand and bentonite has potentially minimized both the radon exhalation rate and the corresponding internal doses.

  14. Carbon dioxide sequestration in oil sands tailings streams

    Energy Technology Data Exchange (ETDEWEB)

    Mikula, R.; Afara, M.; Namsechi, B.; Demko, B.; Wong, P. [Natural Resources Canada, Devon, AB (Canada). CANMET Western Research Centre

    2010-07-01

    This PowerPoint presentation discussed the use of carbon dioxide (CO{sub 2}) as an oil sands tailings process aid and investigated its role in maximizing recycle water availability by rapid consolidation of the transition zone. The potential for CO{sub 2} sequestration was also investigated. CO{sub 2} composite tailings (CT) pilot plants were discussed and the results of cylinder tests and water chemistry analyses were presented. Issues related to physical entrapment, ionic trapping, and mineral trapping were discussed. The study showed that carbonic acid lowers pH, dissolving calcite and dolomite. Aluminum hydroxide groups on the clay surface reacted to produce water and Al{sup 3+} and Na+. Increased bicarbonate and calcium resulted in precipitated calcite. The reduction of a transition zone from 6 to 3 meters increased the available recycle water by 15 mm{sup 3} in a 5 km{sup 2} recycle water pond. Optimum CO{sub 2} additions to whole tailings are now being investigated. tabs., figs.

  15. Advanced characterisation of organic matter in oil sands and tailings sands used for land reclamation by Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS).

    OpenAIRE

    Mareike Noah; Andrea Vieth-Hillebrand; Heinz Wilkes

    2012-01-01

    The Athabasca region of northern Alberta, Canada, is home to deposits of oil sands containing vast amounts (~ 173 billion barrels) of heavily biodegraded petroleum. Oil sands are recovered by surface mining or by in situ steam injection. The extraction of bitumen from oil sands by caustic hot water processing results in large volumes of fluid tailings, which are stored in on-site settling basins. There the tailings undergo a compaction and dewatering process, producing a slowly densifying sus...

  16. Centrifuge - dewatering of oil sand fluid tailings: phase 2 field-scale test

    Energy Technology Data Exchange (ETDEWEB)

    Seto, Jack T.C. [BGC Engineering Inc (Canada); O' Kane, Mike [O' Kane Consultants Inc (Canada); Donahue, Robert [Applied Geochemical Solutions Engineering (Canada); Lahaie, Rick [Syncrude Canada Ltd (Canada)

    2011-07-01

    In order to reduce the accumulation of oil sand fluid fine tailings (FFT) and to create trafficable surfaces for reclamation, Syncrude Canada Ltd. has been studying several tailings technologies. Centrifuge-dewatering is one such technology. This paper discusses the phase 2 field-scale tests for centrifuge-dewatering of oil sand FFT. In centrifuge-dewatering, FFT is diluted and treated with flocculant, then processed through a centrifuge plant and the high-density underflow is transported to a tailings deposit. This technology has evolved since 2005 from laboratory bench scale tests. More than 10,000 cubic meters of centrifuge cake was treated, produced and transported to ten different deposits over a 12-week period from August to October 2010. The amount of solids in FFT was increased from 30% to 50% by centrifuging. Sampled deposits were tested and instrumented for in situ strength. It can be concluded that the deposits can be strengthened and densified by natural dewatering processes like freeze-thaw action and evaporative drying.

  17. Microbially-accelerated consolidation of oil sands tailings. Pathway II: solid phase biogeochemistry

    Directory of Open Access Journals (Sweden)

    Tariq eSiddique

    2014-03-01

    Full Text Available Consolidation of clay particles in aqueous tailings suspensions is a major obstacle to effective management of oil sands tailings ponds in northern Alberta, Canada. We have observed that microorganisms indigenous to the tailings ponds accelerate consolidation of mature fine tailings (MFT during active metabolism by using two biogeochemical pathways. In Pathway I, microbes alter porewater chemistry to indirectly increase consolidation of MFT. Here, we describe Pathway II comprising significant, direct and complementary biogeochemical reactions with MFT mineral surfaces. An anaerobic microbial community comprising Bacteria (predominantly Clostridiales, Synergistaceae and Desulfobulbaceae and Archaea (Methanolinea/Methanoregula and Methanosaeta transformed FeIII minerals in MFT to amorphous FeII minerals during methanogenic metabolism of an added organic substrate. Synchrotron analyses suggested that ferrihydrite (5Fe2O3. 9H2O and goethite (α-FeOOH were the dominant FeIII minerals in MFT. The formation of amorphous iron sulfide (FeS and possibly green rust entrapped and masked electronegative clay surfaces in amended MFT. Both Pathways I and II reduced the surface charge potential (repulsive forces of the clay particles in MFT, which aided aggregation of clays and formation of networks of pores, as visualized using cryo-scanning electron microscopy. These reactions facilitated the egress of porewater from MFT and increased consolidation of tailings solids. These results have large-scale implications for management and reclamation of oil sands tailings ponds, a burgeoning environmental issue for the public and government regulators.

  18. Microbially-accelerated consolidation of oil sands tailings. Pathway II: solid phase biogeochemistry.

    Science.gov (United States)

    Siddique, Tariq; Kuznetsov, Petr; Kuznetsova, Alsu; Li, Carmen; Young, Rozlyn; Arocena, Joselito M; Foght, Julia M

    2014-01-01

    Consolidation of clay particles in aqueous tailings suspensions is a major obstacle to effective management of oil sands tailings ponds in northern Alberta, Canada. We have observed that microorganisms indigenous to the tailings ponds accelerate consolidation of mature fine tailings (MFT) during active metabolism by using two biogeochemical pathways. In Pathway I, microbes alter porewater chemistry to indirectly increase consolidation of MFT. Here, we describe Pathway II comprising significant, direct and complementary biogeochemical reactions with MFT mineral surfaces. An anaerobic microbial community comprising Bacteria (predominantly Clostridiales, Synergistaceae, and Desulfobulbaceae) and Archaea (Methanolinea/Methanoregula and Methanosaeta) transformed Fe(III) minerals in MFT to amorphous Fe(II) minerals during methanogenic metabolism of an added organic substrate. Synchrotron analyses suggested that ferrihydrite (5Fe2O3. 9H2O) and goethite (α-FeOOH) were the dominant Fe(III) minerals in MFT. The formation of amorphous iron sulfide (FeS) and possibly green rust entrapped and masked electronegative clay surfaces in amended MFT. Both Pathways I and II reduced the surface charge potential (repulsive forces) of the clay particles in MFT, which aided aggregation of clays and formation of networks of pores, as visualized using cryo-scanning electron microscopy (SEM). These reactions facilitated the egress of porewater from MFT and increased consolidation of tailings solids. These results have large-scale implications for management and reclamation of oil sands tailings ponds, a burgeoning environmental issue for the public and government regulators.

  19. Integrated oil sands tailings pond water treatment

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Z. [Saskatchewan Research Council, Saskatoon, SK (Canada)

    2010-07-01

    This PowerPoint presentation discussed research currently being conducted to treat oil sands tailings pond water (TPW). The treatment of TPW is challenged by the high level of naphthenic acids (NAs), the slow settling rate of fine particulate materials, and the complex chemistry of the water. The treatment process consisted of bioflocculation, sludge blanket assisted clarification, ozonation, and oil sands coke assisted hybrid biodegradation. The aggregation and adsorption process bound small particles and cells together while also ensuring the passive uptake of pollutants using microbial masses. The mixed liquor then passed through a sludge blanket to ensure enhanced particle capture. An ozonation process was used to increase the biodegradability of the TPW as well as to increase the biodegradability of the residual NAs after ozonation. The process used a hybrid bioreactor that consisted of both suspended and fixed microbial communities. The coke served as a biofilm carrier for the waste. Further studies are being conducted to investigate the efficiency and capability of the process. tabs., figs.

  20. Evaluation of microbial biofilm communities from an Alberta oil sands tailings pond.

    Science.gov (United States)

    Golby, Susanne; Ceri, Howard; Gieg, Lisa M; Chatterjee, Indranil; Marques, Lyriam L R; Turner, Raymond J

    2012-01-01

    Bitumen extraction from the oil sands of Alberta has resulted in millions of cubic meters of waste stored on-site in tailings ponds. Unique microbial ecology is expected in these ponds, which may be key to their bioremediation potential. We considered that direct culturing of microbes from a tailings sample as biofilms could lead to the recovery of microbial communities that provide good representation of the ecology of the tailings. Culturing of mixed species biofilms in vitro using the Calgary Biofilm Device (CBD) under aerobic, microaerobic, and anaerobic growth conditions was successful both with and without the addition of various growth nutrients. Denaturant gradient gel electrophoresis and 16S rRNA gene pyrotag sequencing revealed that unique mixed biofilm communities were recovered under each incubation condition, with the dominant species belonging to Pseudomonas, Thauera, Hydrogenophaga, Rhodoferax, and Acidovorax. This work used an approach that allowed organisms to grow as a biofilm directly from a sample collected of their environment, and the biofilms cultivated in vitro were representative of the endogenous environmental community. For the first time, representative environmental mixed species biofilms have been isolated and grown under laboratory conditions from an oil sands tailings pond environment and a description of their composition is provided.

  1. Next-Generation Sequencing Assessment of Eukaryotic Diversity in Oil Sands Tailings Ponds Sediments and Surface Water.

    Science.gov (United States)

    Aguilar, Maria; Richardson, Elisabeth; Tan, BoonFei; Walker, Giselle; Dunfield, Peter F; Bass, David; Nesbø, Camilla; Foght, Julia; Dacks, Joel B

    2016-11-01

    Tailings ponds in the Athabasca oil sands (Canada) contain fluid wastes, generated by the extraction of bitumen from oil sands ores. Although the autochthonous prokaryotic communities have been relatively well characterized, almost nothing is known about microbial eukaryotes living in the anoxic soft sediments of tailings ponds or in the thin oxic layer of water that covers them. We carried out the first next-generation sequencing study of microbial eukaryotic diversity in oil sands tailings ponds. In metagenomes prepared from tailings sediment and surface water, we detected very low numbers of sequences encoding eukaryotic small subunit ribosomal RNA representing seven major taxonomic groups of protists. We also produced and analysed three amplicon-based 18S rRNA libraries prepared from sediment samples. These revealed a more diverse set of taxa, 169 different OTUs encompassing up to eleven higher order groups of eukaryotes, according to detailed classification using homology searching and phylogenetic methods. The 10 most abundant OTUs accounted for > 90% of the total of reads, vs. large numbers of rare OTUs (< 1% abundance). Despite the anoxic and hydrocarbon-enriched nature of the environment, the tailings ponds harbour complex communities of microbial eukaryotes indicating that these organisms should be taken into account when studying the microbiology of the oil sands. © 2016 The Author(s) Journal of Eukaryotic Microbiology © 2016 International Society of Protistologists.

  2. Retorting of bituminous sands

    Energy Technology Data Exchange (ETDEWEB)

    Chaney, P E; Ince, R W; Mason, C M

    1872-09-26

    This method of recovering oil from mined tar sands involves forming compacted tar sands pieces by special conditioning treatment that provides low internal permeability. The compacted pieces are then retorted in fixed bed form. The conditioning treatment can involve rolling of preformed pellets, compaction in a mold or pressure extrusion. Substantial collapsing of the bed during retorting is avoided. (9 claims) (Abstract only - original article not available from T.U.)

  3. Chemical modification of a bitumen and its non-fuel uses. [Reactions of tar sand asphaltenes in synthesis of non-fuel products

    Energy Technology Data Exchange (ETDEWEB)

    Moschopedis, S.E.; Speight, J.G.

    1974-01-01

    Simple reactions are described whereby tar sand bitumen can be converted to a whole range of materials. Examples are given to illustrate the non-fuel uses of the products. The following reactions of Athabasca asphaltenes are considered: oxidation, halogenation, sulfonation and sulfomethylation, phosphorylation, hydrogenation, reactions with S and O, reactions with metal salts, and miscellaneous chemical conversions. (JGB)

  4. Enriching acid rock drainage related microbial communities from surface-deposited oil sands tailings.

    Science.gov (United States)

    Dean, Courtney; Xiao, Yeyuan; Roberts, Deborah J

    2016-10-01

    Little is known about the microbial communities native to surface-deposited pyritic oil sands tailings, an environment where acid rock drainage (ARD) could occur. The goal of this study was to enrich sulfur-oxidizing organisms from these tailings and determine whether different populations exist at pH levels 7, 4.5, and 2.5. Using growth-based methods provides model organisms for use in the future to predict potential activities and limitations of these organisms and to develop possible control methods. Thiosulfate-fed enrichment cultures were monitored for approximately 1 year. The results showed that the enrichments at pH 4.5 and 7 were established quicker than at pH 2.5. Different microbial community structures were found among the 3 pH environments. The sulfur-oxidizing microorganisms identified were most closely related to Halothiobacillus neapolitanus, Achromobacter spp., and Curtobacterium spp. While microorganisms related to Chitinophagaceae and Acidocella spp. were identified as the only possible iron-oxidizing and -reducing microbes. These results contribute to the general knowledge of the relatively understudied microbial communities that exist in pyritic oil sands tailings and indicate these communities may have a potential role in ARD generation, which may have implications for future tailings management.

  5. The extraction of bitumen from western oil sands. Final report, July 1989--September 1993

    Energy Technology Data Exchange (ETDEWEB)

    Oblad, A.G.; Bunger, J.W.; Dahlstrom, D.A.; Deo, M.D.; Fletcher, J.V.; Hanson, F.V.; Miller, J.D.; Seader, J.D.

    1994-03-01

    Research and development of surface extraction and upgrading processes of western tar sands are described. Research areas included modified hot water, fluidized bed, and rotary kiln pyrolysis of tar sands for extraction of bitumen. Bitumen upgrading included solvent extraction of bitumen, and catalytic hydrotreating of bitumen. Characterization of Utah tar sand deposits is also included.

  6. contaminant migration in a sand aquifer near an inactive uranium tailings impoundment, Elliot Lake, Ontario

    International Nuclear Information System (INIS)

    Morin, K.A.; Cherry, J.A.

    1982-01-01

    An investigation of the movement of contaminated groundwater from inactive uranium tailings through a sand aquifer is being conducted at the Nordic Main tailings impoundment near Elliot Lake, Ontario. During 1979 and 1980, multilevel bundle-type piezometers were installed at several locations around the edge of the tailings impoundment. Chemical analysis of water samples from the bundle piezometers indicate that a major contaminant plume extends outward through a sand aquifer from the southeastern part of the Nordic Main impoundment dam. In the vincinity of the contaminant plume, the sand aquifer varies in thickness from about 9 to 15 m. The plume has two distinct segments, referred to as the inner core and the outer zone. The inner core, which has a pH of 4.3-5.0 and extends about 15 m from the foot of the tailings dam, contains several grams per litre of iron and sulfate, and tens of pCi/L of 226 Ra and 210 Pb. Water levels in piezometers within the inner core show that groundwater is moving horizontally, away from the tailings impoundment, with a velocity of up to several hundred metres per year. The outer zone, which extends a few hundred metres downgradient from the dam, is characterized by hundreds to thousands of milligrams per litre of iron and sulfate, less than 15pCi/L of 226 Ra, and a pH greater than 5.7. Comparison of 1979 and 1980 data shows that the front of the inner core is advancing a few metres per year, which is less than a few percent of the groundwater velocity. This retardation of movement of the inner core is caused by neutralization of the acidic water as a result of dissolution of calcium carbonate in the sand. With the rise in pH, precipitation of iron carbonate and possibly some iron hydroxide occurs and the contaminants of main concern such as 226 Ra, 210 Pb, and uranium are removed from solution by adsorption or coprecipitation

  7. The chemical and biological evolution of mature fine tailings in oil sands end-pit lakes

    International Nuclear Information System (INIS)

    Chen, M.; Weisener, C.; Ciborowski, J.

    2010-01-01

    This presentation described an innovative bench-scale technique to characterize oil sand tailings and their impact on sediment oxygen demand (SOD) for future end-pit lake model behaviour. SOD is a dominant contributor to oxygen depletion in wetlands. The function and sustainability of a wetland ecosystem depends on the biochemical processes occurring at the sediment-water interface. The biochemical reactions associated with natural sediment can change with the addition of oil sands processed material (OSPM), which can affect SOD and ecosystem viability. It is important to establishing the biotic and abiotic controls of SOD. In order to evaluate the effectiveness of current wetland reclamation designs, it is important to establish the biotic and abiotic controls of SOD. The REDOX chemistry of fresh tailings sediment (MFT) was measured in this laboratory microcosm to determine the chemical and biological influences, and to study the role of developing microbial communities as new mature fine tailings (MFT) age. The study evaluated the changes in the main chemical, physical and biological populations of the MFT in both aerobic and anaerobic microcosms. A combination of microelectrode arrays and DNA profiling at the tailings water interface was used in the study.

  8. Geotechnical field investigation of the rapid densification phenomenon in oil sands mature fine tailings

    Energy Technology Data Exchange (ETDEWEB)

    Guo, C.; Chalaturnyk, R.J.; Scott, J.D.; Cyre, G. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering; MacKinnon, M. [Syncrude Canada Ltd., Edmonton, AB (Canada). Edmonton Research Centre

    2002-07-01

    The Mildred Lake Settling Basin (MLSB) is an oil sand tailings pond with a water area of about 11 square km and a maximum depth of mature fine tailings (MFT) of about 50 m, rendering it Syncrude's largest disposal site for tailings. Syncrude began storing the MFT in 1978 but in recent years there has been a sharp increase in the consolidation of the fine tailings, creating pumping challenges in the transfer of tailings from the MLSB for the creation of composite tailings. This paper presents preliminary results of field and laboratory study which have been launched to better manage the rapid densification of fine tailings. The study involves sampling, field vane tests, cone penetration tests, steel plate penetration tests and earth pressure measurements. Methane producing microorganisms have become very active in the part of the pond that is experiencing rapid densification. The objective of the study was to determine the inventory and distribution of high strength MFT in current storage ponds and to assess whether geotechnical properties are enough to support direct loading with solids such as sand, clay or coke. The cause of the phenomena was also examined along with ways to possibly enhance MFT development through microbial, physical or chemical treatments. Results show that the accumulation of methane gas may have reached a critical state in some parts of the pond. The densification phenomenon at the southern pond is more significant compared to the northern pond. Earth pressure measurements indicate that the earth pressure cell has good sensitivity and that the coefficient of earth pressure at rest is approximately one. Good agreement was reached between different testing methods used to determine geotechnical properties of MFT. 5 refs., 4 tabs., 14 figs.

  9. Reclamation research for the future at Syncrude Canada Ltd. : soil simulation-revegetation studies on tailings sand

    Energy Technology Data Exchange (ETDEWEB)

    Fedkenheuer, A W; Browne, J

    1979-12-01

    In response to the rising demand for energy in today's world, oil extracted from oil sands has become a viable energy source. Syncrude Canada Ltd. is a 2.2 billion dollar oil sands surface mining and processing venture situated in the Athabasca oil sands of northeastern Alberta. It is located near the town of Fort McMurray approximately 420 km north of Edmonton. During its planned 25 years of mine life, Syncrude expects to produce more than 1 billion barrels of oil from a 2800 ha mine area. Syncrude is committed to reclaiming this immense mine area. The reclamation objective is to return the disturbed site to a vegetative cover having a productivity which is equal to or greater than that which existed prior to disturbance. The reclaimed area must also be compatible with the neighboring natural areas. To accomplish this the vast quantities of tailings sand (that is, the leftover sand from which the oil has been extracted) must be reformed into a soil which is capable of supporting native plant communities. Researchers at Syncrude are looking for ways to use indigenous materials with the tailings sand to simulate a naturally-formed soil. Native plant species are being tested to see how well they will grow in such simulated soils and to evaluate their potential for use in large scale reclamation projects. This brochure describes the soil simulation-revegetation experiments going on at Syncrude.

  10. Bio-physicochemical effects of gamma irradiation treatment for naphthenic acids in oil sands fluid fine tailings

    Energy Technology Data Exchange (ETDEWEB)

    Boudens, Ryan; Reid, Thomas; VanMensel, Danielle; Sabari Prakasanm, M.R. [Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON (Canada); Ciborowski, Jan J.H. [Biological Sciences, University of Windsor, Windsor, ON (Canada); Weisener, Christopher G., E-mail: weisener@uwindsor.ca [Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON (Canada)

    2016-01-01

    Naphthenic acids (NAs) are persistent compounds that are components of most petroleum, including those found in the Athabasca oil sands. Their presence in freshly processed tailings is of significant environmental concern due to their toxicity to aquatic organisms. Gamma irradiation (GI) was used to reduce the toxicity and concentration of NAs in oil sands process water (OSPW) and fluid fine tailings (FFT). This investigation systematically studied the impact of GI on the biogeochemical development and progressive reduction of toxicity using laboratory incubations of fresh and aged tailings under anoxic and oxic conditions. GI reduced NA concentrations in OSPW by up to 97% in OSPW and in FFT by 85%. The GI-treated FFT exhibited increased rates of biogeochemical change, dependent on the age of the tailings source. Dissolved oxygen (DO) flux was enhanced in GI-treated FFT from fresh and aged source materials, whereas hydrogen sulfide (HS{sup −}) flux was stimulated only in the fresh FFT. Acute toxicity to Vibrio fischeri was immediately reduced following GI treatment of fresh OSPW. GI treatment followed by 4-week incubation reduced toxicity of aged OSPW to V. fischeri. - Highlights: • Gamma irradiation substantially reduced concentrations of ecotoxic naphthenic acids • Acute toxicity was reduced in gamma irradiated process water • Gamma irradiated tailings exhibited increased rates of microbial respiration.

  11. Oil sands thickened froth treatment tailings exhibit acid rock drainage potential during evaporative drying.

    Science.gov (United States)

    Kuznetsov, Petr; Kuznetsova, Alsu; Foght, Julia M; Siddique, Tariq

    2015-02-01

    Bitumen extraction from oil sands ores after surface mining produces different tailings waste streams: 'froth treatment tailings' are enriched in pyrite relative to other streams. Tailings treatment can include addition of organic polymers to produce thickened tailings (TT). TT may be further de-watered by deposition into geotechnical cells for evaporative drying to increase shear strength prior to reclamation. To examine the acid rock drainage (ARD) potential of TT, we performed predictive analyses and laboratory experiments on material from field trials of two types of thickened froth treatment tailings (TT1 and TT2). Acid-base accounting (ABA) of initial samples showed that both TT1 and TT2 initially had net acid-producing potential, with ABA values of -141 and -230 t CaCO₃ equiv. 1000 t(-1) of TT, respectively. In long-term kinetic experiments, duplicate ~2-kg samples of TT were incubated in shallow trays and intermittently irrigated under air flow for 459 days to simulate evaporative field drying. Leachates collected from both TT samples initially had pH~6.8 that began decreasing after ~50 days (TT2) or ~250 days (TT1), stabilizing at pH~2. Correspondingly, the redox potential of leachates increased from 100-200 mV to 500-580 mV and electrical conductivity increased from 2-5 dS m(-1) to 26 dS m(-1), indicating dissolution of minerals during ARD. The rapid onset and prolonged ARD observed with TT2 is attributed to its greater pyrite (13.4%) and lower carbonate (1.4%) contents versus the slower onset of ARD in TT1 (initially 6.0% pyrite and 2.5% carbonates). 16S rRNA gene pyrosequencing analysis revealed rapid shift in microbial community when conditions became strongly acidic (pH~2) favoring the enrichment of Acidithiobacillus and Sulfobacillus bacteria in TT. This is the first report showing ARD potential of TT and the results have significant implications for effective management of pyrite-enriched oil sands tailings streams/deposits. Copyright © 2014

  12. Application of toxicity testing in the evaluation of reclamation options for oil sands fine tails

    International Nuclear Information System (INIS)

    Nelson, L.R.; MacKinnon, M.; Gulley, J.R.

    1993-01-01

    The hot water process for the extraction of bitumen from oil sands leads to the production of large volumes of wastewater and the formation of a large inventory of fine clay tailings. This fine tailings material and its associated water are acutely toxic to various aquatic test organisms during bioassays. An overview is presented of toxicity testing at Syncrude and Suncor, the application of toxicity testing to fine tailings management, and the role in reclamation planning. The main acutely toxic component of the tailings is the polar organic acid fraction, specifically naphthanates. These naphthanates are readily degraded biologically by indigenous microbial populations. Toxicity testing is aimed at assessing the degree of both acute and chronic toxicity and the long term potential for the input of toxins into the environment from various proposed reclamation measures. 28 refs., 6 figs., 2 tabs

  13. Copper tailings in stucco mortars

    Directory of Open Access Journals (Sweden)

    Osvaldo Pavez

    Full Text Available Abstract This investigation addressed the evaluation of the use of copper tailings in the construction industry in order to reduce the impact on the environment. The evaluation was performed by a technical comparison between stucco mortars prepared with crushed conventional sand and with copper tailings sand. The best results were achieved with the stucco mortars containing tailings. The tailings presented a fine particles size distribution curve different from that suggested by the standard. The values of compressive strength, retentivity, and adherence in the stucco mortars prepared with copper tailings were much higher than those obtained with crushed sand. According to the results from this study, it can be concluded that the preparation of stucco mortars using copper tailings replacing conventional sand is a technically feasible alternative for the construction industry, presenting the benefit of mitigating the impact of disposal to the environment.

  14. Presentations of the CONRAD tailings seminar : exploring the past, present and future of tailings technologies

    International Nuclear Information System (INIS)

    2004-01-01

    This symposium explored oil sand tailings activities in Canada and their associated technologies. It was attended by active and prospective tailings researchers and developers of tailings technology who addressed timely issues regarding mature fine tailings, consolidated tailings, thickened tailings, and emerging tailings technologies. The collaborative research projects that are underway at the Oil Sands Tailings Research Facility were also discussed along with other topics such as tailings ponds management, water treatment, water quality and water supply security. All 16 presentations featured at this conference were indexed separately for inclusion in this database

  15. Preferential methanogenic biodegradation of short-chain n-alkanes by microbial communities from two different oil sands tailings ponds.

    Science.gov (United States)

    Mohamad Shahimin, Mohd Faidz; Foght, Julia M; Siddique, Tariq

    2016-05-15

    Oil sands tailings ponds harbor diverse anaerobic microbial communities capable of methanogenic biodegradation of solvent hydrocarbons entrained in the tailings. Mature fine tailings (MFT) from two operators (Albian and CNRL) that use different extraction solvents were incubated with mixtures of either two (n-pentane and n-hexane) or four (n-pentane, n-hexane, n-octane and n-decane) n-alkanes under methanogenic conditions for ~600 d. Microbes in Albian MFT began methane production by ~80 d, achieving complete depletion of n-pentane and n-hexane in the two-alkane mixture and their preferential biodegradation in the four-alkane mixture. Microbes in CNRL MFT preferentially metabolized n-octane and n-decane in the four-alkane mixture after a ~80 d lag but exhibited a lag of ~360 d before commencing biodegradation of n-pentane and n-hexane in the two-alkane mixture. 16S rRNA gene pyrosequencing revealed Peptococcaceae members as key bacterial n-alkane degraders in all treatments except CNRL MFT amended with the four-alkane mixture, in which Anaerolineaceae, Desulfobacteraceae (Desulfobacterium) and Syntrophaceae (Smithella) dominated during n-octane and n-decane biodegradation. Anaerolineaceae sequences increased only in cultures amended with the four-alkane mixture and only during n-octane and n-decane biodegradation. The dominant methanogens were acetoclastic Methanosaetaceae. These results highlight preferential n-alkane biodegradation by microbes in oil sands tailings from different producers, with implications for tailings management and reclamation. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Study on tar generated from downdraft gasification of oil palm fronds.

    Science.gov (United States)

    Atnaw, Samson Mekbib; Kueh, Soo Chuan; Sulaiman, Shaharin Anwar

    2014-01-01

    One of the most challenging issues concerning the gasification of oil palm fronds (OPF) is the presence of tar and particulates formed during the process considering its high volatile matter content. In this study, a tar sampling train custom built based on standard tar sampling protocols was used to quantify the gravimetric concentration of tar (g/Nm3) in syngas produced from downdraft gasification of OPF. The amount of char, ash, and solid tar produced from the gasification process was measured in order to account for the mass and carbon conversion efficiency. Elemental analysis of the char and solid tar samples was done using ultimate analysis machine, while the relative concentration of the different compounds in the liquid tar was determined making use of a liquid gas chromatography (GC) unit. Average tar concentration of 4.928 g/Nm3 and 1.923 g/Nm3 was obtained for raw gas and cleaned gas samples, respectively. Tar concentration in the raw gas sample was found to be higher compared to results for other biomass materials, which could be attributed to the higher volatile matter percentage of OPF. Average cleaning efficiency of 61% which is comparable to that of sand bed filter and venturi scrubber cleaning systems reported in the literature was obtained for the cleaning system proposed in the current study.

  17. Study on Tar Generated from Downdraft Gasification of Oil Palm Fronds

    Directory of Open Access Journals (Sweden)

    Samson Mekbib Atnaw

    2014-01-01

    Full Text Available One of the most challenging issues concerning the gasification of oil palm fronds (OPF is the presence of tar and particulates formed during the process considering its high volatile matter content. In this study, a tar sampling train custom built based on standard tar sampling protocols was used to quantify the gravimetric concentration of tar (g/Nm3 in syngas produced from downdraft gasification of OPF. The amount of char, ash, and solid tar produced from the gasification process was measured in order to account for the mass and carbon conversion efficiency. Elemental analysis of the char and solid tar samples was done using ultimate analysis machine, while the relative concentration of the different compounds in the liquid tar was determined making use of a liquid gas chromatography (GC unit. Average tar concentration of 4.928 g/Nm3 and 1.923 g/Nm3 was obtained for raw gas and cleaned gas samples, respectively. Tar concentration in the raw gas sample was found to be higher compared to results for other biomass materials, which could be attributed to the higher volatile matter percentage of OPF. Average cleaning efficiency of 61% which is comparable to that of sand bed filter and venturi scrubber cleaning systems reported in the literature was obtained for the cleaning system proposed in the current study.

  18. Study on Tar Generated from Downdraft Gasification of Oil Palm Fronds

    Science.gov (United States)

    Atnaw, Samson Mekbib; Kueh, Soo Chuan; Sulaiman, Shaharin Anwar

    2014-01-01

    One of the most challenging issues concerning the gasification of oil palm fronds (OPF) is the presence of tar and particulates formed during the process considering its high volatile matter content. In this study, a tar sampling train custom built based on standard tar sampling protocols was used to quantify the gravimetric concentration of tar (g/Nm3) in syngas produced from downdraft gasification of OPF. The amount of char, ash, and solid tar produced from the gasification process was measured in order to account for the mass and carbon conversion efficiency. Elemental analysis of the char and solid tar samples was done using ultimate analysis machine, while the relative concentration of the different compounds in the liquid tar was determined making use of a liquid gas chromatography (GC) unit. Average tar concentration of 4.928 g/Nm3 and 1.923 g/Nm3 was obtained for raw gas and cleaned gas samples, respectively. Tar concentration in the raw gas sample was found to be higher compared to results for other biomass materials, which could be attributed to the higher volatile matter percentage of OPF. Average cleaning efficiency of 61% which is comparable to that of sand bed filter and venturi scrubber cleaning systems reported in the literature was obtained for the cleaning system proposed in the current study. PMID:24526899

  19. Trace metal mobilization from oil sands froth treatment thickened tailings exhibiting acid rock drainage.

    Science.gov (United States)

    Kuznetsova, Alsu; Kuznetsov, Petr; Foght, Julia M; Siddique, Tariq

    2016-11-15

    Froth treatment thickened tailings (TT) are a waste product of bitumen extraction from surface-mined oil sands ores. When incubated in a laboratory under simulated moist oxic environmental conditions for ~450d, two different types of TT (TT1 and TT2) exhibited the potential to generate acid rock drainage (ARD) by producing acid leachate after 250 and 50d, respectively. We report here the release of toxic metals from TT via ARD, which could pose an environmental threat if oil sands TT deposits are not properly managed. Trace metal concentrations in leachate samples collected periodically revealed that Mn and Sr were released immediately even before the onset of ARD. Spikes in Co and Ni concentrations were observed both pre-ARD and during active ARD, particularly in TT1. For most elements measured (Fe, Cr, V, As, Cu, Pb, Zn, Cd, and Se), leaching was associated with ARD production. Though equivalent acidification (pH2) was achieved in leachate from both TT types, greater metal release was observed from TT2 where concentrations reached 10,000ppb for Ni, 5000ppb for Co, 3000ppb for As, 2000ppb for V, and 1000ppb for Cr. Generally, metal concentrations decreased in leachate with time during ARD and became negligible by the end of incubation (~450d) despite appreciable metals remaining in the leached TT. These results suggest that using TT for land reclamation purposes or surface deposition for volume reduction may unfavorably impact the environment, and warrants application of appropriate strategies for management of pyrite-enriched oil sands tailings streams. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Investigating the Microbial Degradation Potential in Oil Sands Fluid Fine Tailings Using Gamma Irradiation: A Metagenomic Perspective.

    Science.gov (United States)

    VanMensel, Danielle; Chaganti, Subba Rao; Boudens, Ryan; Reid, Thomas; Ciborowski, Jan; Weisener, Christopher

    2017-08-01

    Open-pit mining of the Athabasca oil sands has generated large volumes of waste termed fluid fine tailings (FFT), stored in tailings ponds. Accumulation of toxic organic substances in the tailings ponds is one of the biggest concerns. Gamma irradiation (GI) treatment could accelerate the biodegradation of toxic organic substances. Hence, this research investigates the response of the microbial consortia in GI-treated FFT materials with an emphasis on changes in diversity and organism-related stimuli. FFT materials from aged and fresh ponds were used in the study under aerobic and anaerobic conditions. Variations in the microbial diversity in GI-treated FFT materials were monitored for 52 weeks and significant stimuli (p tailings biogeochemistry and the impacts of GI treatment on microorganisms as an effect for targeting toxic organics. The outcomes of this study highlight the potential for this approach to accelerate stabilization and reclamation end points. Graphical Abstract.

  1. Initial geochemical characteristics of fluid fine tailings in an oil sands end pit lake

    Energy Technology Data Exchange (ETDEWEB)

    Dompierre, Kathryn A. [Department of Civil and Geological Engineering, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5A9 (Canada); Lindsay, Matthew B.J., E-mail: matt.lindsay@usask.ca [Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2 (Canada); Cruz-Hernández, Pablo [Department of Geology, University of Huelva, Campus ‘El Carmen’, E-21071 Huelva (Spain); Halferdahl, Geoffrey M. [Environmental Research and Development, Syncrude Canada Limited, Edmonton, Alberta T6N 1H4 (Canada)

    2016-06-15

    Geochemical characteristics of fluid fine tailings (FFT) were examined in Base Mine Lake (BML), which is the first full-scale demonstration oil sands end pit lake (EPL) in northern Alberta, Canada. Approximately 186 Mm{sup 3} of FFT was deposited between 1994 and 2012, before BML was established on December 31, 2012. Bulk FFT samples (n = 588) were collected in July and August 2013 at various depths at 15 sampling sites. Temperature, solid content, electrical conductivity (EC), pH, Eh and alkalinity were measured for all samples. Detailed geochemical analyses were performed on a subset of samples (n = 284). Pore-water pH decreased with depth by approximately 0.5 within the upper 10 m of the FFT. Major pore-water constituents included Na (880 ± 96 mg L{sup −1}) and Cl (560 ± 95 mg L{sup −1}); Ca (19 ± 4.1 mg L{sup −1}), Mg (11 ± 2.0 mg L{sup −1}), K (16 ± 2.3 mg L{sup −1}) and NH{sub 3} (9.9 ± 4.7 mg L{sup −1}) were consistently observed. Iron and Mn concentrations were low within FFT pore water, whereas SO{sub 4} concentrations decreased sharply across the FFT–water interface. Geochemical modeling indicated that FeS{sub (s)} precipitation was favoured under SO{sub 4}-reducing conditions. Pore water was also under-saturated with respect to gypsum [CaSO{sub 4}·2H{sub 2}O], and near saturation with respect to calcite [CaCO{sub 3}], dolomite [CaMg(CO{sub 3}){sub 2}] and siderite [FeCO{sub 3}]. X-ray diffraction (XRD) suggested that carbonate-mineral dissolution largely depleted calcite and dolomite. X-ray absorption near edge structure (XANES) spectroscopy revealed the presence of FeS{sub (s)}, pyrite [FeS{sub 2}], and siderite. Carbonate-mineral dissolution and secondary mineral precipitation have likely contributed to FFT dewatering and settlement. However, the long-term importance of these processes within EPLs remains unknown. These results provide a reference for assessing the long-term geochemical evolution of oil sands EPLs, and offer

  2. Coal Tar and Coal-Tar Pitch

    Science.gov (United States)

    Learn about coal-tar products, which can raise your risk of skin cancer, lung cancer, and other types of cancer. Examples of coal-tar products include creosote, coal-tar pitch, and certain preparations used to treat skin conditions such as eczema, psoriasis, and dandruff.

  3. A Critical Review of the Oil and Tar Sands of the Dahomey Basin

    International Nuclear Information System (INIS)

    Osundina, A.; Mustapha, A.; Nzewi, T.

    2002-01-01

    The Benin Basin previously referred to as the Dahomey embayment has been designated as a frontier basin within Nigeria due to its potentially high prospects, but comparatively low exploitation campaign to date. The basin offers a promising opportunity for heavy oil exploration in a narrow belt extending westward from Edo State to the republic of Benin; while offshore, there are high prospects for finding more conventional hydrocarbon.The eastern Dahomey embayment is known to have an extensive reserve of hydrocarbons (bitumen and tar sands). The sediments occur in a 5 8 km belt stretching 120km from the fringes of Lagos State through Ogun, Ondo and Edo States. The estimated reserve potentials exceed 30 billion barrels of oil equivalent.Recently acquired seismic data in OPL 309 and 310, and subsequent drilling of 2 wells on the narrow continental shelf, have shown the presence of closed structures over Basement Highs and other related structural styles in the basin and confirm that conventional light oils and condensates hydrocarbons occur in commercial quantity. These hydrocarbons are reservoired in stratigraphic sequences of Albian Cenomanian age.This paper hopes to expose the hidden riches of this Basin and hopefully get the attention of the big players in refocusing their interests in the basin that attracted attention of the early petroleum explorers to Nigeria approximately 100 years ago

  4. Strength and Microstructure of Concrete with Iron Ore Tailings as Replacement for River Sand

    Directory of Open Access Journals (Sweden)

    Umara Shettima Ali

    2018-01-01

    Full Text Available River Sand is one of the basic ingredients used in the production of concrete. Consequently, continuous consumption of sand in construction industry contributes significantly to depletion of natural resources. To achieve more sustainable construction materials, this paper reports the use of iron ore tailings (IOT as replacement for river sand in concrete production. IOT is a waste product generated from the production of iron ore and disposed to land fill without any economic value. Concrete mixtures containing different amount of IOT were designed for grade C30 with water to cement ratio of 0.60. The percentage ratios of the river sand replacements by IOT were 25%, 50%, 75% and 100%. Concrete microstructure test namely, XRD and Field Emission Scanned Electron Microscopic/Energy dispersive X-ray Spectroscopy (FESEM/EDX were conducted for control and IOT concretes in order to determine the interaction and performance of the concrete containing IOT. Test results indicated that the slump values of 130 mm and 80 to 110 mm were recorded for the control and IOT concretes respectively. The concrete sample of 50% IOT recorded the highest compressive strength of 37.7 MPa at 28 days, and the highest flexural strength of 5.5 MPa compared to 4.7 MPa for reference concrete. The texture of the IOT is rough and angular which was able to improve the strength of the concrete.

  5. Strength and Microstructure of Concrete with Iron Ore Tailings as Replacement for River Sand

    Science.gov (United States)

    Umara Shettima, Ali; Ahmad, Yusof; Warid Hussin, Mohd; Zakari Muhammad, Nasiru; Eziekel Babatude, Ogunbode

    2018-03-01

    River Sand is one of the basic ingredients used in the production of concrete. Consequently, continuous consumption of sand in construction industry contributes significantly to depletion of natural resources. To achieve more sustainable construction materials, this paper reports the use of iron ore tailings (IOT) as replacement for river sand in concrete production. IOT is a waste product generated from the production of iron ore and disposed to land fill without any economic value. Concrete mixtures containing different amount of IOT were designed for grade C30 with water to cement ratio of 0.60. The percentage ratios of the river sand replacements by IOT were 25%, 50%, 75% and 100%. Concrete microstructure test namely, XRD and Field Emission Scanned Electron Microscopic/Energy dispersive X-ray Spectroscopy (FESEM/EDX) were conducted for control and IOT concretes in order to determine the interaction and performance of the concrete containing IOT. Test results indicated that the slump values of 130 mm and 80 to 110 mm were recorded for the control and IOT concretes respectively. The concrete sample of 50% IOT recorded the highest compressive strength of 37.7 MPa at 28 days, and the highest flexural strength of 5.5 MPa compared to 4.7 MPa for reference concrete. The texture of the IOT is rough and angular which was able to improve the strength of the concrete.

  6. Taming the tailings : dead ducks notwithstanding, extensive research is underway to deal with oilsands tailings in a more efficient manner

    Energy Technology Data Exchange (ETDEWEB)

    Collison, M.

    2008-09-15

    Research is now being conducted to reduce the environmental impacts of oil sands tailing ponds. Alberta's oil sands region contains an estimated 60 km{sup 2} of tailings ponds, which serve as holding basins for recycled water as well as collection sites for materials used in reclamation activities. The ponds contain residual bitumen, production chemicals, and minerals. While some of the water in the ponds can be re-used, mature fine tailings must be contained behind dikes. Every barrel of bitumen produced by the industry results in the creation of 1.5 barrels of mature fine tailings. Natural Resources Canada's CANMET Energy Technology Centre is currently conducting a research program with the University of Alberta to reduce the amounts of tailings produced by the industry. Options for dry stackable tailings are being explored, as well as methods of using the tailings to enhance various oil sands processes. It is hoped that the dry, stackable tailings can be used to help reclaim and rebuild Boreal regions impacted by the oil sands industry. The program is gaining interest due to concerns that leakages from the tailings ponds may pollute aquifers and rivers in a region noted for its water shortages. Research teams are also investigating the use of flocculants to create heavy non-segregated tailings. Researchers are also examining methods of recovering hydrocarbons, titanium, and zircon from the tailings. 3 figs.

  7. Water management challenges and perspective for surface oil sands operations in North Eastern Alberta

    International Nuclear Information System (INIS)

    MacKinnon, M.

    2009-01-01

    Oil sands waters has many sources, such as raw water inputs (import water and hydrologic waters); oil sands ore water such as formation water; and oil sands process-affected water (OSPW) such as produced water and released water from tailings. This presentation demonstrated the importance of water to oil sands operations and indicated how oil sands processing affects water quality. Water imports to meet oil sands needs is a topic of particular interest. Other topics that were presented included water properties changing during oil sands operations; tailings management and the effects on water quality; oil sands tailings and water management and the impact on water quality of the region; how oil sands processing affected water quality; and current tailings approach and proposed new tailings methods and the effects on water composition. Post extraction changes in OSPW and the potential impacts of engineered tailings were also discussed. It was concluded that water treatment options must meet water management objectives. figs.

  8. Reports on 1974 result of Sunshine Project. Research on tar sand and oil shale; 1974 nendo tar sand oyobi oil shale ni kansuru chosa kenkyu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1975-04-04

    The purpose of this research is to grasp the policy of the oil sand resource countries, the properties and existing conditions of the resources, effects of the oil sand resources on a long term energy supply/demand, etc., and to clarify the meaning and position of the researches on the development of oil sand resources in the future energy policy of Japan. The quantities of oil sand resources are mostly in the process of investigation except Alberta province of Canada and are estimated to be two trillion barrels. The quantity for which strip mining is possible is about 90 billion barrels, which are mostly located in the Athabasca region. The oil sand holding countries take a policy of positively developing oil sand. No barriers are particularly provided against the introduction of foreign technology and capital. Where the prospects are possible for the development of oil sand are Canada and Venezuela. R and D should be emphasized on the refining of bitumen and the extraction method within the oil reservoir. The investment per b/d is about 15-20 thousand dollars, which is likely to be more than twice as much as for the North Sea oilfields. The properties and quality of the synthetic crude oil are superior while the risk of exploitation is small; therefore, oil sand will be competitive with crude oil in the future. (NEDO)

  9. AL-PAM assisted filtration of mature fine tailings produced from oil sands development

    Energy Technology Data Exchange (ETDEWEB)

    Alamgir, A.; Masliyah, J.; Xu, Z. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering

    2010-07-01

    The inventory of mature fine tailings (MFT) produced by the oil sands extraction process continues to grow, and is considered as a long-term environmental liability. Large amounts of water are trapped in the MFT, and the tailings ponds present a threat to local wildlife and ecosystems. This PowerPoint presentation discussed a research project that is being conducted to identify conditions for producing stackable MFT deposits. The study is investigating various types and dosages of polymers and evaluating the degrees of MFT dilution and process configurations needed to maximize re-usable water recovery. Polymeric flocculants include AL-PAM and Magnafloc 1011. Settling tests have demonstrated that 50 ppm is the optimum dosage for both polymers when MFT is diluted to 5 wt percent solids, while 75 ppm of AL-PAM and 100 ppm of MF1011 are optimum dosages for MFT diluted to 10 wt percent solids. A novel supernatant filtration method was then used to produce filtration cakes and water. The study showed that the supernatant can be used to further dilute the MFTs. tabs., figs.

  10. Bioassay for uranium mill tailings

    International Nuclear Information System (INIS)

    Tschaeche, A.N.

    1986-01-01

    Uranium mill tailings are composed of fine sand that contains, among other things, some uranium (U/sup 238/ primarily), and all of the uranium daughters starting with /sup 230/Th that are left behind after the usable uranium is removed in the milling process. Millions of pounds of tailings are and continue to be generated at uranium mills around the United States. Discrete uranium mill tailings piles exist near the mills. In addition, the tailings materials were used in communities situated near mill sites for such purposes as building materials, foundations for buildings, pipe runs, sand boxes, gardens, etc. The Uranium Mill Tailings Remedial Action Project (UMTRAP) is a U.S. Department of Energy Program designed with the intention of removing or stabilizing the mill tailings piles and the tailings used to communities so that individuals are not exposed above the EPA limits established for such tailings materials. This paper discusses the bioassay programs that are established for workers who remove tailings from the communities in which they are placed

  11. Sub-stratum injection of fine tailings

    Energy Technology Data Exchange (ETDEWEB)

    Kesteren van, W.; Cornelisse, J.; Costello, M. [Deltares, Delft (Netherlands)

    2010-07-01

    This PowerPoint presentation discussed an experiment conducted to evaluate the sub-stratum injection of oil sands fine tailings. The hydraulic fracturing method was developed as a sub-surface dredging process for mining sand without removing the overburden. Pressure was used to transport the sand-water mixture, and the high pressures used in the process resulted in water losses through the clay-sand interface. The experiment was conducted with soft clay, compacted sand, and an injection feed. Results of the study showed that the injection method may be successful. However, further research is required to characterize the fracture energy of oil sands and the rheology of fine tailings. Horizontal hydraulic fracturing equations were presented. Tensile failures in clay and oil sands were discussed. Fractures were identified by deformation and discharge rates. Crack propagation methods were also studied. tabs., figs.

  12. Canada's oil sands: nuclear power in an integrated energy economy

    Energy Technology Data Exchange (ETDEWEB)

    Isaacs, E. [Alberta Energy Research Inst., Calgary, Alberta (Canada)

    2008-07-01

    This paper discusses the role of nuclear power in Canada's oil sands industry. It outlines the oil sands resource in Alberta and the various industrial projects to recover the oil from the tar sands. It points to continuing innovation in technology since the 1930's. The hydrogen required for upgrading bitumen is made from natural gas. Finally, it discusses the next wave of oil sands production technologies.

  13. In-situ caging of wood frog (Rana sylvatica) larvae in wetlands formed from oil sands tailings materials (OSPM)

    Energy Technology Data Exchange (ETDEWEB)

    Hersikorn, B.; Smits, J.E. [Saskatchewan Univ., Saskatoon, SK (Canada)

    2009-07-01

    The reclamation of oil sand tailings through the formation of wetlands was examined during the spring and summer of 2006 and 2007 in a mesocosm study of indigenous amphibians (wood frogs). In both years, frogs were exposed to wetlands containing oil sands process-affected materials (OSPM) and reference wetlands that did not contain any OSPM. In year 2 there were 14 sites, of which 7 were reference sites and 7 were OSPM- affected sites. The sites were classified as older or younger than 7 yrs. Four enclosures, each containing 50 tadpoles, were placed in each wetland. Survival time to metamorphosis, and thyroid hormone ratios of larvae raised in young OSPM wetlands were found to be different from those of reference wetlands and old OSPM wetlands. This presentation also provided data on liver EROD activity and whole-body triglyceride concentrations. The study showed that the formation of wetlands from tailings material may support populations of amphibians if the wetlands are given the time to age. The development and health of native amphibians reflects the sustainability of the different reclamation strategies and delineates how higher trophic level organisms may be affected by OSPM.

  14. Coal tar phototherapy for psoriasis reevaluated: erythemogenic versus suberythemogenic ultraviolet with a tar extract in oil and crude coal tar

    International Nuclear Information System (INIS)

    Lowe, N.J.; Wortzman, M.S.; Breeding, J.; Koudsi, H.; Taylor, L.

    1983-01-01

    Recent studies have questioned the therapeutic value of coal tar versus ultraviolet (UV) radiation and their relative necessity in phototherapy for psoriasis. In this investigation, different aspects of tar phototherapy have been studied in single-blind bilateral paired comparison studies. The effects of 1% crude coal tar were compared with those of petrolatum in conjunction with erythemogenic and suberythemogenic doses of ultraviolet light (UVB) using a FS72 sunlamp tubed cabinet. Crude coal tar was clinically superior to petrolatum with suberythemogenic ultraviolet. With the erythemogenic UVB, petrolatum was equal in efficacy to crude coal tar. Suberythemogenic UVB was also used adjunctively to compare the effects of a 5% concentration of a tar extract in an oil base to 5% crude coal tar in petrolatum or the oil base without tar. The tar extract in oil plus suberythemogenic UVB produced significantly more rapid improvement than the oil base plus UVB. The direct bilateral comparison of equal concentrations of tar extract in oil base versus crude coal tar in petrolatum in a suberythemogenic UV photo regimen revealed no statistical differences between treatments. In a study comparing tar extract in oil and the oil base without ultraviolet radiation, the tar extract in oil side responded more rapidly

  15. Recreating wetland ecosystems in an oil sands disturbed landscape : Suncor consolidated-tailings demonstration wetlands

    Energy Technology Data Exchange (ETDEWEB)

    Daly, C. [Suncor Energy, Fort McMurray, AB (Canada). Aquatic Reclamation Research; Tedder, W.; Marlowe, P. [Golder Associates Ltd., Calgary, AB (Canada). Oil Sands Div.

    2009-10-01

    Open pit oil sands mining involves the disturbance of thin overburden covers of Boreal forest lands that must be returned to equivalent land capability after mining activities have ceased. Before mining starts, any wetlands are drained, timber is harvested, and peat, topsoils and subsoils are stockpiled for later use. This article discussed wetland reclamation activities conducted by Suncor Energy at its open pit mining operations. Research facilities were constructed in order to determine if wetlands constructed with consolidated tailings (CT) and pond effluent water (PEW) were able to support a sustainable vegetation community. Thirty-three cat-tail plots were established at the facility as well as unplanted plots in order to determine how quickly natural establishment occurred. Shoreline plug transplants and transplants from a natural saline lake were also introduced. Within 5 years, over 23 plant species had naturally colonized the CT wetlands. However, diversity was lower in CT and PEW-constructed wetlands. It was concluded that the application of a native peat-mineral mix soil may help to increase plant diversity. 20 refs., 5 figs.

  16. Chemical mass transport between fluid fine tailings and the overlying water cover of an oil sands end pit lake

    Science.gov (United States)

    Dompierre, Kathryn A.; Barbour, S. Lee; North, Rebecca L.; Carey, Sean K.; Lindsay, Matthew B. J.

    2017-06-01

    Fluid fine tailings (FFT) are a principal by-product of the bitumen extraction process at oil sands mines. Base Mine Lake (BML)—the first full-scale demonstration oil sands end pit lake (EPL)—contains approximately 1.9 × 108 m3 of FFT stored under a water cover within a decommissioned mine pit. Chemical mass transfer from the FFT to the water cover can occur via two key processes: (1) advection-dispersion driven by tailings settlement; and (2) FFT disturbance due to fluid movement in the water cover. Dissolved chloride (Cl) was used to evaluate the water cover mass balance and to track mass transport within the underlying FFT based on field sampling and numerical modeling. Results indicated that FFT was the dominant Cl source to the water cover and that the FFT is exhibiting a transient advection-dispersion mass transport regime with intermittent disturbance near the FFT-water interface. The advective pore water flux was estimated by the mass balance to be 0.002 m3 m-2 d-1, which represents 0.73 m of FFT settlement per year. However, the FFT pore water Cl concentrations and corresponding mass transport simulations indicated that advection rates and disturbance depths vary between sample locations. The disturbance depth was estimated to vary with location between 0.75 and 0.95 m. This investigation provides valuable insight for assessing the geochemical evolution of the water cover and performance of EPLs as an oil sands reclamation strategy.

  17. A DEVICE AND METHOD FOR MEASURING TAR IN A TAR-ENVIRONMENT

    DEFF Research Database (Denmark)

    2017-01-01

    The present disclosure describes a device and corresponding method for measuring tar in a tar environment, e.g., a tar producing environment such as a stove or a combustion engine, based on UV absorption spectroscopy. A first measurement along an optical path in the tar environment is performed...

  18. Some properties of Suncor oil sands tailings

    Energy Technology Data Exchange (ETDEWEB)

    Guo, C.; Wells, P.S. [Suncor Energy, Fort McMurray, AB (Canada)

    2010-07-01

    This PowerPoint presentation discussed a pond assessment program conducted by Suncor to determine the properties of mature fine tailings (MFT) and composite tailings (CT) at reclaimed and unreclaimed sites. Mudline and sonar depth sounding techniques were used to determine solids contents. A wire line sampler provided point depth samples used for laboratory analyses. Continuous drill samples were obtained in order to characterize bottom fines and clay content. A flow penetration tests was used to determine the undrained shear strength of the soft tailings. A 3-D block model was then used to estimate soft material properties and to generate material distribution volumes and tonnages for different property ranges. The study showed that the block modelling techniques provide a more accurate tailings pond assessment than traditional approaches. While slow, ongoing static consolidation was observed, surface capping and artificial dewatering are required to provide trafficable ground for the final reclamation of the sites. tabs., figs.

  19. Estimation of bitumen and clay content in fine tailings

    International Nuclear Information System (INIS)

    Motta Cabrera, S.C.; Bryan, J.; Kantzas, A.

    2007-01-01

    Fine tailings are the components of tailings ponds and the by-product of the oil sand extraction process, consisting mostly of water with small amounts of bitumen, sand, silts and clays. Because of the large volumes of tailings, an important environmental and production process issue involves the reduction of the remaining bitumen in the tailings stream. This paper presented the results of a study that used low field nuclear magnetic resonance (NMR) in order to estimate the bitumen, clay and water content of synthetic tailings samples. NMR is a non-destructive technique that is utilized to determine compositions of oil and brine emulsions and the viscosity of heavy oil and bitumen as well as in reservoir characterization, measuring properties such as permeability, porosity, mobile and immobile fluids, and fluid saturations. The study prepared and tested numerous samples with variable water, bitumen, sand and clay concentrations in the NMR tool under ambient conditions. Two qualities of water and bitumen were used to prepare the synthetic samples. Each type of water and bitumen was analyzed as a single substance and in a mixture with the typical solids found in tailings composition. These included kaolinite, illite, sodium montmorillonite and sand. These synthetic samples were analyzed using different mixing configurations, as a function of time and in two different NMR tools. It was concluded that NMR is a potential application for on-line determination of tailings streams composition. 18 refs., 3 tabs., 17 figs

  20. Centennial review-forecast--oil sands, shales spar for markets

    Energy Technology Data Exchange (ETDEWEB)

    Pamenter, C B

    1967-09-01

    The relationship between possible developments of tar sands and oil shale deposits to the future of the oil and gas industry is examined. The Athabasca tar sands are estimated to contain 85 billion bbl of synthetic crude oil which can be exploited using currently available mining equipment and proven techniques. Another 240 billion bbl of synthetic crude are potentially available through in-situ extraction methods. Great Canadian Oil Sands Ltd. is using an extraction procedure which involves a surface mining operation, extraction and processing of the bitumen, and product shipments via a 266-mile pipeline. This procedure will be used to produce 45,000 bpd of synthetic crude and 300 ton per day of sulfur. Syncrude Canada Ltd. and Shell Canada Ltd. both have applied to the Alberta government for permission to operate 100,000-bpd operations. Syncrudes is a mining operation and Shell plans to use in-situ extraction. A number of companies have conducted research projects concerning shale oil recovery. The majority of these projects have been aimed at improving mining operations. In-situ retorting of kerogen and extraction of oil has also received consideration.

  1. The Drainage Consolidation Modeling of Sand Drain in Red Mud Tailing and Analysis on the Change Law of the Pore Water Pressure

    Directory of Open Access Journals (Sweden)

    Chuan-sheng Wu

    2014-01-01

    Full Text Available In order to prevent the occurring of dam failure and leakage, sand-well drainages systems were designed and constructed in red mud tailing. It is critical to focus on the change law of the pore water pressure. The calculation model of single well drainage pore water pressure was established. The pore water pressure differential equation was deduced and the analytical solution of differential equation using Bessel function and Laplace transform was given out. The impact of parameters such as diameter d, separation distance l, loading rate q, and coefficient of consolidation Cv in the function on the pore water pressure is analyzed by control variable method. This research is significant and has great reference for preventing red mud tailings leakage and the follow-up studies on the tailings stability.

  2. Coal tar in dermatology

    Energy Technology Data Exchange (ETDEWEB)

    Roelofzen, J.H.J.; Aben, K.K.H.; Van Der Valk, P.G.M.; Van Houtum, J.L.M.; Van De Kerkhof, P.C.M.; Kiemeney, L.A.L.M. [Radboud University Nijmegen Medical Center, Nijmegen (Netherlands). Dept. of Dermatology

    2007-07-01

    Coal tar is one of the oldest treatments for psoriasis and eczema. It has anti-inflammatory, antibacterial, antipruritic and antimitotic effects. The short-term side effects are folliculitis, irritation and contact allergy. Coal tar contains carcinogens. The carcinogenicity of coal tar has been shown in animal studies and studies in occupational settings. There is no clear evidence of an increased risk of skin tumors or internal tumors. Until now, most studies have been fairly small and they did not investigate the risk of coal tar alone, but the risk of coal tar combined with other therapies. New, well-designed, epidemiological studies are necessary to assess the risk of skin tumors and other malignancies after dermatological use of coal tar.

  3. Sedimentological and Scanning Electron Miscroscopic Descriptions of Afowo Oil Sand Deposits, South Western Nigeria

    Directory of Open Access Journals (Sweden)

    Akinmosin A

    2017-12-01

    Full Text Available Sedimentological and scanning electron microscopic analyses of some shallow reservoir tar sand samples in parts of Southwestern Nigeria were carried out with the aim of characterizing the reservoir properties in relation to bitumen saturation and recovery efficiency. The production of impregnated tar from the sands requires the reservoir to be of good quality. A total of thirty samples were collected at different localities within the tar sand belt (ten out of these samples were selected for various reservoir quality analyses based on their textural homogeneity. The result of particle size distribution study showed that bulk of the sands is medium – coarse grained and moderately sorted. The grain morphologies are of low to high sphericity with shapes generally sub-angular to sub-rounded, implying that the sands have undergone a fairly long transportation history with depositional energy having a moderate to high velocity. The quartz content was made up of about 96% of the total mineralogical components; the sediments of the Afowo Formation can be described to be mineralogically and texturally stable. The result of the scanning electron microscopy (SEM analysis revealed that the oil sands contained minerals which had been precipitated and occurred as pore filling cement; these minerals include sheet kaolinite, block kaolinite, vermiform kaolinite, pyrite crystals and quartz. The SEM images also showed micro-pores ranging from 0.057µm to 0.446µm and fractures. The study showed that the clay minerals contained in the Afowo reservoir rocks were mainly kaolinite. Kaoline unlike some other clays (e.g Montimorillonite does not swell with water, hence it is not expected to have any negative effects on the reservoir quality, especially during enhanced oil recovery operations.

  4. Tailings management at Nabarlek

    International Nuclear Information System (INIS)

    Waggitt, P.

    1989-01-01

    As the entire uranium deposit at Nabarlek was mined in 1979, the mine pit was available as a tailing's repository from the time of commencement of ore processing. In the early years Nabarlek's tailings were deposited subaqueously. In 1985 the tailings deposition method was changed to a sub-aerial, or semi-dry, method. Over the subsequent three years there was evidence that the tailings settled further and squeezed water from lower layers. The water was pumped away and treated for removal of radium before being evaporated in one of the mine's evaporation ponds. When milling was completed in 1988 it was decided to try and increase the rate of water removal and so obtain even greater consolidation of the trailings in a shorter time. This was achieved by loading the tailings with a layer of screened leached sands and waste rock placed on a layer of geotextile filter fabric that had been laid over the whole of the tailings surface in the pit. Once this was completed a modified piling rig was used to insert vertical drains, or wicks, up to 30 metres into the tailings. The drains were placed on a square grid at a spacing of 3.25 metres. Water that was forced out of the tailings by the downward pressure of the sand and rock could flow freely to the surface up these drains. Once at the surface the water was gathered into a sump and pumped away for treatment as before. The drains are working very well at present although it will be some considerable time before the water stops flowing. Already settlement of the tailings is apparent and the settled density of the material is increasing. As far as is known this is the first time that such a system has been employed on mine tailings in a pit in this way

  5. Characterization and utilization of hydrotreated products produced from the Whiterocks (Utah) tar sand bitumen-derived liquid

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, C.H.; Longstaff, D.C.; Deo, M.D.; Hanson, F.V.; Oblad, A.G.

    1991-12-31

    The bitumen-derived liquid produced in a 4-inch diameter fluidized-bed reactor from the mined and crushed ore from the Whiterocks tar sand deposit has been hydrotreated in a fixed-bed reactor. The purpose was to determine the extent of upgrading as a function of process operating variable. A sulfided nickel-molybendum on alumina hydrodenitrogenation catalyst was used in all experiments. Moderately severe operating conditions were employed; that is, high reaction temperature (617--680 K) high reactor pressure (11.0--17.1 MPa) and low liquid feed rate (0.18--0.77 HSV); to achieve the desired reduction in heteroatom content. Detailed chemical structures of the bitumen-derived liquid feedstock and the hydrotreated total liquid products were determined by high resolution gas chromatography - mass spectrometry analyses. The compounds identified in the native bitumen included isoprenoids; bicyclic, tricycle, and tetracyclic terpenoids; steranes; hopanes; and perhydro-{beta}-carotenes. In addition, normal and branched alkanes and alkenes and partially dehydrogenated hydroaromatics were identified in the bitumen-derived liquid. The dominant pyrolysis reactions were: (1) the dealkylation of long alkyl side chains to form {alpha} - and isoolefins; and (2) the cleavage of alkyl chains linking aromatic and hydroaromatic clusters. Olefinic bonds were not observed in the hydrotreated product and monoaromatic hydrocarbons were the predominant aromatic species. The properties of the jet fuel fractions from the hydrotreated products met most of the jet fuel specifications. The cetane indices indicated these fractions would be suitable for use as diesel fuels.

  6. Characterization and utilization of hydrotreated products produced from the Whiterocks (Utah) tar sand bitumen-derived liquid

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, C.H.; Longstaff, D.C.; Deo, M.D.; Hanson, F.V.; Oblad, A.G.

    1991-01-01

    The bitumen-derived liquid produced in a 4-inch diameter fluidized-bed reactor from the mined and crushed ore from the Whiterocks tar sand deposit has been hydrotreated in a fixed-bed reactor. The purpose was to determine the extent of upgrading as a function of process operating variable. A sulfided nickel-molybendum on alumina hydrodenitrogenation catalyst was used in all experiments. Moderately severe operating conditions were employed; that is, high reaction temperature (617--680 K) high reactor pressure (11.0--17.1 MPa) and low liquid feed rate (0.18--0.77 HSV); to achieve the desired reduction in heteroatom content. Detailed chemical structures of the bitumen-derived liquid feedstock and the hydrotreated total liquid products were determined by high resolution gas chromatography - mass spectrometry analyses. The compounds identified in the native bitumen included isoprenoids; bicyclic, tricycle, and tetracyclic terpenoids; steranes; hopanes; and perhydro-{beta}-carotenes. In addition, normal and branched alkanes and alkenes and partially dehydrogenated hydroaromatics were identified in the bitumen-derived liquid. The dominant pyrolysis reactions were: (1) the dealkylation of long alkyl side chains to form {alpha} - and isoolefins; and (2) the cleavage of alkyl chains linking aromatic and hydroaromatic clusters. Olefinic bonds were not observed in the hydrotreated product and monoaromatic hydrocarbons were the predominant aromatic species. The properties of the jet fuel fractions from the hydrotreated products met most of the jet fuel specifications. The cetane indices indicated these fractions would be suitable for use as diesel fuels.

  7. Treatment of lignite tars, etc

    Energy Technology Data Exchange (ETDEWEB)

    1936-08-07

    A process is described for treating tars such as lignite tar, shale tar, or peat tar, and similar tars, characterized by the fact that the tar is rectified to about 240/sup 0/C and the residue brought to a temperature above 50/sup 0/C after diluting with a product of the type of gasoline or ligroin at about 30/sup 0/C and treated with selective solvents preferably low-boiling phenols and eventually with water.

  8. Enabling technologies for oil sands development

    International Nuclear Information System (INIS)

    Bailey, R.T.

    1998-01-01

    A review of oil sands production and expansion possibilities in Alberta were presented. The enabling technologies for oil sands projects include mining (bucketwheels, draglines, trucks, shovels conveyors, slurry hydrotransport); extraction (conditioning tumblers, pipelines, tanks, hot water, caustic, cold water, frothers); froth cleaning (centrifuges, solvent treatment); tailings (tailings ponds, consolidated tailings); and upgrading (coking, hydrotreating for SCO, hydrocracking and multiple products). The enabling technologies for in situ production include cyclic steam stimulation for vertical wells, steam assisted gravity drainage (SAGD) for dual horizontal wells, and cold production with wormholes. This paper described the recovery potentials of each of these processes. It also discussed the role of government and industry in research and cooperative research involving both the private and public sectors. Examples of each of these were described such as SAGD, the OSLO cold water extraction process, The consolidated tailings (CT) project, the low energy extraction process (slurry production, hydrotransport, pipeline conditioning and warm water extraction), and research in fine tailings, to demonstrate that although objectives may differ, government and industry research objectives are complementary

  9. Indian coal tars. II

    Energy Technology Data Exchange (ETDEWEB)

    Basu, A N; Bhatnagar, J N; Roy, A K

    1954-01-01

    Laboratory experiments were carried out on these efforts: (1) rank and specific-gravity fractions on tar yield; (2) addition of water to the coal charge, or steam during carbonization, on yield of tar and tar acids; (3) the presence of a cracking agent (shale) with and without steam addition on the yield of tar and tar acids (the particular shale used without steam reduced the yield, and the restricted use of steam brought the yield to the former noncatalyzed level); and (4) catalytic effect of three different samples of shale, firebrick, quartz, coke, and silica-alumina on the cracking of tar acids (the most active were two of the shales, a freshly-prepared coke, and the Al/sub 2/O/sub 3/-SiO/sub 2/ catalysts that gave conversion up to 98%). The products were mainly carbon, aromatic hydrocarbons of the naphthalene series and gases (CO and H/sub 2/). The yield of the tar becomes less as coal of lower specific gravity is used or when higher temperatures are used for carbonization. The mineral matter associated with Indian coals acts as a decomposition catalyst for tar acids, as shown by experiments on the decomposition of PhOH at temperatures above 800/sup 0/.

  10. Tar bases in low-temperature coal tar

    Energy Technology Data Exchange (ETDEWEB)

    Sugiura, S; Ueno, H; Yokoyama, H

    1951-01-01

    Tar bases were extracted from three fractions, that boil below 260/sup 0/ at 260/sup 0/ to 280/sup 0/, and 280/sup 0/ to 330/sup 0/, respectively, of the low-temperature tar obtained by the carbonization of Ube coal in a Koppers' vertical retort at approximately 750/sup 0/. These were divided, respectively, into three groups, acetate-forming amine, HCl salt-forming bases (I), and CHCl/sub 3/-soluble bases (II), and further fractionally distilled. From the physical and chemical properties of the fractions thus obtained, it was concluded that low-temperature coal tar contained no low boiling pyridine homologues and that, besides higher homologues of pyridine, nonaromatic, more saturated, and less basic compounds of larger atomic weight and smaller refractive index, such as derivatives of pyrrole and indole, also existed as in crude petroleum.

  11. Consolidation of tailings

    International Nuclear Information System (INIS)

    Nelson, J.D.; Wardwell, R.E.; Abt, S.R.; Staub, W.P.

    1983-09-01

    The integrity of cover systems placed on tailings impoundments will be affected by the potential for differential settlement of the tailings surface. Settlement of the sand fraction will occur relatively rapidly. The slimes will take longer time for consolidation and will produce greater settlement. This report reviews the phenomenon of consolidation for saturated and unsaturated tailings. The effect of load application by cover placement and the extent to which dewatering of tailings will cause consolidation are considered. In addition, the feasibility of inducing consolidation by alternative means and the potential applicability of these methods to tailings impoundments reclamation are discussed. Differential settlement of the tailings will cause tensile strain to be developed in covers. This strain could be large enough to cause cracking within a relatively brittle compacted clay. Dewatering of tailings by drainage can cause settlement even greater than that by placement of a cover material. Dewatering of the tailings would also increase the stability of the tailings surface, thereby enhancing reclamation operations. Consequently, in view of the enhanced surface stability and the fact that a portion of the differential settlement can be accomplished prior to cover placement, dewatering of tailings impoundments during operations may have benefical effects

  12. A novel waste water cleanup, fines sequestration and consolidation technology for oil sands applications

    Energy Technology Data Exchange (ETDEWEB)

    Soane, D.; Ware, W.; Mahoney, R.; Kincaid, P. [Soane Energy LLC, Cambridge, MA (United States)

    2010-07-01

    This paper discussed a wastewater technology designed to rapidly sequester suspended fines and other pollutants from the tailings produced during oil sands processes. The technology can also be used to clarify existing tailings ponds, and is expected to help address growing environmental concerns over the remediation of oil sands tailings. The ATA system is comprised of the following 3 components: (1) an activator polymer, (2) a tether polymer, and (3) an anchor particle. A small dose of the activator polymer is added to the fine or mature tailings, which then causes the suspended clay fines to aggregate. The anchor particles are then coated with the tether polymer. The anchor particle is formed from sand derived from coarser tailings. The tether-bearing anchor particles bind to the aggregated clay fines in the activated tailings to form robust complexes that can easily be separated from the waste stream. Output streams from the ATA process include a clean water stream that can be reused in oil sands extraction processes; and a dewatered solid that can be used as landfill as well as in construction and reclamation applications. The sensible heat retained in the recycled water is expected to also reduce the energy requirements of the oil sands extraction process. 6 refs., 1 tab., 5 figs.

  13. Process of treating tars

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, C; Hempel, H; Weissenburger, H

    1955-05-05

    A process is described for treating tars or tar oils, especially carbonization tars, characterized in that the tars or tar oils are mixed with benzene or light oils which contain no aromatic material or only slight amounts, or with gas oil in such amounts that the asphalt precipitates, and after separation of the precipitated material the mixture is treated with caustic solution for separation of the phenols, and after separation of the phenolate liquor the mixture is subjected to heating for removal of the dilution medium, then the remaining oil can be used as heating oil or it is submitted to distillation for the purpose of recovering a fuel suitable for diesel motors, while the phenolate liquor is worked up into phenols.

  14. Oil-sands giants leaving smaller environmental footprints

    International Nuclear Information System (INIS)

    Stonehouse, D.

    1999-01-01

    Suncor Energy and Syncrude Canada are both investing billions of dollars to increase production at their mining facilities near Fort McMurray, Alberta. The two oil-sand giants will be spending a good portion of their investment (almost $1 billion) to improve their environmental performance. Both companies are focusing on reducing their energy use to cut production costs and to reduce carbon dioxide (CO 2 ) emissions. Currently, oil-sand mining accounts for the largest industrial use of electricity in Alberta. This produces tremendous amounts of greenhouse gases such as CO 2 which has been linked to global warming. By year 2006, all of Syncrude's processing equipment will be replaced by energy-efficient equipment. Shovel/truck/hydrotransport will replace the dragline/bucket-wheel/conveyor system used in the past. New technology designed to improve bitumen recovery and increase upgrading processing yields is also expected to decrease emissions by 5 million tonnes per year. Syncrude will also construct a $60 million gas turbine generator for its Aurora project. Sulphur dioxide (SO 2 ) emissions which cause acid rain, are also on the decline at both Syncrude and Suncor. Suncor will reduce its energy use through the construction of a $315 million cogeneration plant which will generate 220 MV of electricity for its operations, along with waste heat that will be used to separate the heavy oil from the sand. The cogeneration plant will be 45 per cent more efficient that current operations. Both companies have planted millions of trees and shrubs to reclaim nearly 3,000 hectares of land. The tailings from oil-sand mining are currently being captured in settling basins. Both companies have long range plans for dealing with tailings. The first is called water capping which involves layering fresh water over tailing deposits to create a lake. The second is called composite tails, which involves mixing the tailings with gypsum and sand to make them settle faster

  15. Effects of weather and tailings properties on tailings drying times

    Energy Technology Data Exchange (ETDEWEB)

    Gantzer, C.; Fasking, T.; Costello, M.; Greenwood, J. [Barr Engineering, Calgary, AB (Canada)

    2010-07-01

    This PowerPoint presentation presented the results of a study conducted to determine the effects of weather and tailings properties on tailings drying times. Weather conditions have a significant impact the potential evaporation (PE) and actual evaporation (AE) of oil sands tailings. A 2-stage drying of slurry at a constant PE was conducted to determine the shrinkage limit of untreated mature fine tailings (MFT). An evaporation and seepage model was used to determine maximum first-stage drying rates. Measurements were also taken in a wind tunnel. Potential evaporation rates were calculated and evaporative water losses from the MFT were determined. Estimated drying times were presented. Results of the approach were compared with field measurements conducted in a previous study. Results of the study showed that evaporative water loss rates for May through August were limited by the properties of the tailings. Water loss rates were limited by weather for other months in the year-long study. tabs., figs.

  16. Topical tar: Back to the future

    Energy Technology Data Exchange (ETDEWEB)

    Paghdal, K.V.; Schwartz, R.A. [University of Medicine & Dentistry of New Jersey, Newark, NJ (United States)

    2009-08-15

    The use of medicinal tar for dermatologic disorders dates back to the ancient times. Although coal tar is utilized more frequently in modern dermatology, wood tars have also been widely employed. Tar is used mainly in the treatment of chronic stable plaque psoriasis, scalp psoriasis, atopic dermatitis, and seborrheic dermatitis, either alone or in combination therapy with other medications, phototherapy, or both. Many modifications have been made to tar preparations to increase their acceptability, as some dislike its odor, messy application, and staining of clothing. One should consider a tried and true treatment with tar that has led to clearing of lesions and prolonged remission times. Occupational studies have demonstrated the carcinogenicity of tar; however, epidemiologic studies do not confirm similar outcomes when used topically. This article will review the pharmacology, formulations, efficacy, and adverse effects of crude coal tar and other tars in the treatment of selected dermatologic conditions.

  17. Variation of Pore Water Pressure in Tailing Sand under Dynamic Loading

    Directory of Open Access Journals (Sweden)

    Jia-xu Jin

    2018-01-01

    Full Text Available Intense vibration affects the pore water pressure in a tailing dam, with the tendency to induce dam liquefaction. In this study, experiments were performed wherein model tailing dams were completely liquefied by sustained horizontal dynamic loading to determine the effects of the vibration frequency, vibration amplitude, and tailing density on the pore water pressure. The results revealed four stages in the increase of the tailing pore water pressure under dynamic loading, namely, a slow increase, a rapid increase, inducement of structural failure, and inducement of complete liquefaction. A lower frequency and smaller amplitude of the vibration were found to increase the time required to achieve a given pore water pressure in dense tailings. Under the effect of these three factors—vibration frequency and amplitude and tailing density—the tailing liquefaction time varied nonlinearly with the height from the base of the tailing dam, with an initial decrease followed by an increase. The pore pressure that induced structural failure also gradually decreased with increasing height. The increase in the tailing pore pressure could be described by an S-shaped model. A complementary multivariate nonlinear equation was also derived for predicting the tailing pore water pressure under dynamic loading.

  18. Removing tar information from cigarette packages may reduce South Korean smokers' misconceptions about low-tar cigarettes

    Directory of Open Access Journals (Sweden)

    Hye-Jin Paek

    2018-03-01

    Full Text Available Background Many smokers still have misconceptions about “light” or “low tar” cigarettes. In South Korea, low-tar (< 3 mg cigarette sales have increased sharply from 1.8% in 2002 to 49.2% in 2015. Although government regulations forbid cigarette packages from displaying messages such as “mild,” “low-tar,” and “light,” numbers indicating tar amounts are still permitted. This study examines whether removing tar information from packaging altogether reduces people's misconceptions about low tar cigarettes. Methods An online experiment was conducted among 531 smokers who were randomly assigned to one of two conditions. In the “tar” condition, 271 participants were shown in random order three cigarette packages for three major brands (Esse, The One, Marlboro with different tar amounts. In the “no-tar” condition, 260 participants were shown the same packages without tar information. Next, participants evaluated which type of cigarette was mildest, least harmful, easier for nonsmokers to start smoking, and easier for smokers to quit. After descriptive statistics were checked, twelve sets of chi-square tests were performed. Results Average age of the participants was 26.22 (14 - 62 years; 53.5% were male. All 12 chi-square tests were statistically significant. Participants in the tar condition judged the lowest-tar cigarette to be mildest, least harmful, easier to start, and easier to quit. In the no-tar condition, for the Korean brands Esse and The One, most respondents evaluated all cigarette types to be the same only for harm, ease of starting, and ease of quitting; for Marlboro, judgments were the same as those in the tar condition except that “easier to quit” was judged to be the same across the three types. Conclusions Banning tar information from cigarette packages may help reduce smokers' misconceptions about low-tar cigarettes. People have inconsistent judgments about differently packaged cigarettes when tar

  19. Effect of naphtha diluent on greenhouse gases and reduced sulfur compounds emissions from oil sands tailings.

    Science.gov (United States)

    Gee, Kathleen F; Poon, Ho Yin; Hashisho, Zaher; Ulrich, Ania C

    2017-11-15

    The long-term storage of oil sands tailings has resulted in the evolution of greenhouse gases (CH 4 and CO 2 ) as a result of residual organics biodegradation. Recent studies have identified black, sulfidic zones below the tailings-water interface, which may be producing toxic sulfur-containing gases. An anaerobic mesocosm study was conducted over an 11-week period to characterize the evolution of CH 4 , CO 2 and reduced sulfur compounds (RSCs) (including H 2 S) in tailings as it relates to naphtha-containing diluent concentrations (0.2, 0.8, and 1.5% w/v) and microbial activity. Our results showed that RSCs were produced first at 0.12μmol°RSCs/mL MFT (1.5% w/v diluent treatment). RSCs contribution (from highest to lowest) was H 2 S and 2-methylthiophene>2.5-dimethylthiophene>3-methylthiophene>thiofuran>butyl mercaptan>carbonyl sulfide, where H 2 S and 2-methylthiophene contributed 81% of the gas produced. CH 4 and CO 2 production occurred after week 5 at 40.7μmolCH 4 /mL MFT and 5.9μmolCO 2 /mL MFT (1.5% w/v diluent treatment). The amount of H 2 S and CH 4 generated is correlated to the amount of diluent present and to microbial activity as shown by corresponding increases in sulfate-reducers' Dissimilatory sulfite reductase (DsrAB) gene and methanogens' methyl-coenzyme M reductase (MCR) gene. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Distilling tar; distillation, destructive

    Energy Technology Data Exchange (ETDEWEB)

    Brash, P; Young, W

    1866-09-17

    The tarry residue, which separates on treating crude shale oil with sulfuric acid, is redistilled, in the manner described in Specification No. 1278, A.D. 1866, together with shale. Previous to the distillation, the acid is neutralized with lime, or may be separated by blowing steam into the tar and adding salt. The purified tar thus obtained is absorbed by ashes, or is mixed with lime or other alkaline matter, or the shale may be mixed with lime and distilled with the tar, which is allowed to flow over and through the shale during the process. The tar obtained in the purification of natural paraffin may be similarly utilized.

  1. Summary of research and information needs for the management of selected onshore energy minerals: oil shale, tar sands, arctic oil and gas, and uranium. Final report 1982-83

    Energy Technology Data Exchange (ETDEWEB)

    1983-11-01

    The report assesses research needs for the management, regulation, reclamation, and conservation of oil shale, tar sands, arctic oil and gas, and uranium deposits currently under federal jurisdiction and concludes that additional research is required to achieve the goals of good management, including conservation, protection of life and property, and minimization of environmental degradation. The report recommends (1) establishment of a standing advisory scientific and engineering committee on onshore minerals management research to influence future research directions and implementation; (2) development of a comprehensive library and data center for research results; and (3) encouragement of the operation of demonstration-scale production facilities where they are lacking. More detailed summaries of current knowledge and perceived research needs are to be found in the four interim reports of the committee.

  2. Settlement of uranium mill tailings

    International Nuclear Information System (INIS)

    Chen, P.K.; Guros, F.B.; Keshian, B.

    1988-01-01

    Two test embankments were constructed on top of an old tailings deposit near Ambrosia Lake, New Mexico to determine settlement characteristics of hydraulically- deposited uranium mill tailings. Before construction of the embankments, properties of in-situ tailings and foundation soils were determined using data from boreholes, piezocone soundings, and laboratory tests. These properties were used to estimate post-construction settlement of a planned disposal embankment to be constructed on the tailings. However, excessive uncertainty existed in the following: field settlement rates of saturated and unsaturated tailings, degree of preconsolidation of the upper 15 feet of tailings, and the ability of an underlying silty sand foundation layer to facilitate drainage. Thus, assurance could not be provided that differential settlements of the radon barrier and erosion protection layers would be within allowable limits should the planned disposal embankment be constructed in a single-stage

  3. The extraction of bitumen from western oil sands

    International Nuclear Information System (INIS)

    Oblad, A.G.; Bunger, J.W.; Dahlstrom, D.A.; Deo, M.D.; Hanson, F.V.; Miller, J.D.; Seader, J.D.

    1992-08-01

    The University of Utah tar sand research and development program is concerned with research and development on Utah is extensive oil sands deposits. The program has been intended to develop a scientific and technological base required for eventual commercial recovery of the heavy oils from oil sands and processing these oils to produce synthetic crude oil and other products such as asphalt. The overall program is based on mining the oil sand, processing the mined sand to recover the heavy oils and upgrading them to products. Multiple deposits are being investigated since it is believed that a large scale (approximately 20,000 bbl/day) plant would require the use of resources from more than one deposit. The tasks or projects in the program are organized according to the following classification: Recovery technologies which includes thermal recovery methods, water extraction methods, and solvent extraction methods; upgrading and processing technologies which covers hydrotreating, hydrocracking, and hydropyrolysis; solvent extraction; production of specialty products; and environmental aspects of the production and processing technologies. These tasks are covered in this report

  4. Compromised metamorphosis and thyroid hormone changes in wood frogs (Lithobates sylvaticus) raised on reclaimed wetlands on the Athabasca oil sands

    International Nuclear Information System (INIS)

    Hersikorn, Blair D.; Smits, Judit E.G.

    2011-01-01

    The wet landscape approach to oil sands tailings reclamation in the Athabasca Oil Sands region involves creating wetlands from fluid tailings in mined-out pits. We measured time to metamorphosis, thyroid hormone status, and detoxification enzyme (EROD) induction in Wood frog (Lithobates sylvaticus) tadpoles raised on reclaimed oil sands wetlands of different ages [young (≤7 yr) vs. old (>7 yr)] and compared data with tadpoles raised on reference (control) wetlands. Metamorphosis was delayed or never occurred in tadpoles raised in young tailings; those exposed to older tailings developed similarly to those in reference wetlands. Thyroid hormone disruption likely played an important role in the metamorphosis delay as the T3:T4 ratio was lowest in tadpoles raised in young, tailings-affected wetlands. Our findings suggest tailings wetlands become less toxic with age, and that these amphibians will be able to complete their life cycle in tailing wetlands that have sufficiently detoxified with age. - This work provides guidance for reclamation of oil sands tailings and shows the usefulness of frogs and caging studies in environmental toxicology.

  5. Compromised metamorphosis and thyroid hormone changes in wood frogs (Lithobates sylvaticus) raised on reclaimed wetlands on the Athabasca oil sands

    Energy Technology Data Exchange (ETDEWEB)

    Hersikorn, Blair D., E-mail: blair.hersikorn@usask.c [Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, Saskatchewan, S7N 5B3 (Canada); Smits, Judit E.G., E-mail: judit.smits@ucalgary.c [Faculty of Veterinary Medicine, University of Calgary, 3280 Hospital Drive NW, Calgary, Alberta, T2N 4Z6 (Canada)

    2011-02-15

    The wet landscape approach to oil sands tailings reclamation in the Athabasca Oil Sands region involves creating wetlands from fluid tailings in mined-out pits. We measured time to metamorphosis, thyroid hormone status, and detoxification enzyme (EROD) induction in Wood frog (Lithobates sylvaticus) tadpoles raised on reclaimed oil sands wetlands of different ages [young ({<=}7 yr) vs. old (>7 yr)] and compared data with tadpoles raised on reference (control) wetlands. Metamorphosis was delayed or never occurred in tadpoles raised in young tailings; those exposed to older tailings developed similarly to those in reference wetlands. Thyroid hormone disruption likely played an important role in the metamorphosis delay as the T3:T4 ratio was lowest in tadpoles raised in young, tailings-affected wetlands. Our findings suggest tailings wetlands become less toxic with age, and that these amphibians will be able to complete their life cycle in tailing wetlands that have sufficiently detoxified with age. - This work provides guidance for reclamation of oil sands tailings and shows the usefulness of frogs and caging studies in environmental toxicology.

  6. Levels of polycyclic aromatic hydrocarbons and dibenzothiophenes in wetland sediments and aquatic insects in the oil sands area of northeastern Alberta, Canada.

    Science.gov (United States)

    Wayland, Mark; Headley, John V; Peru, Kerry M; Crosley, Robert; Brownlee, Brian G

    2008-01-01

    An immense volume of tailings and tailings water is accumulating in tailings ponds located on mine leases in the oil sands area of Alberta, Canada. Oil sands mining companies have proposed to use tailings- and tailings water-amended lakes and wetlands as part of their mine remediation plans. Polycyclic aromatic hydrocarbons (PAHs) are substances of concern in oil sands tailings and tailings water. In this study, we determined concentrations of PAHs in sediments, insect larvae and adult insects collected in or adjacent to three groups of wetlands: experimental wetlands to which tailings or tailings water had been purposely added, oil sands wetlands that were located on the mine leases but which had not been experimentally manipulated and reference wetlands located near the mine leases. Alkylated PAHs dominated the PAH profile in all types of samples in the three categories of wetlands. Median and maximum PAH concentrations, especially alkylated PAH concentrations, tended to be higher in sediments and insect larvae in experimental wetlands than in the other types of wetlands. Such was not the case for adult insects, which contained higher than expected levels of PAHs in the three types of ponds. Overlap in PAH concentrations in larvae among pond types suggests that any increase in PAH levels resulting from the addition of tailings and tailings water to wetlands would be modest. Biota-sediment accumulation factors were higher for alkylated PAHs than for their parent counterparts and were lower in experimental wetlands than in oil sands and reference wetlands. Research is needed to examine factors that affect the bioavailability of PAHs in oil sands tailings- or tailings water-amended wetlands.

  7. Effect of Carbon and Nitrogen Sources on Polygalacturonase Production by Trichoderma viride (BITRS-1001 Isolated from Tar Sand in Ondo State, Nigeria

    Directory of Open Access Journals (Sweden)

    Ogunmolu, F. E.

    2011-01-01

    Full Text Available The effects of the various carbon and nitrogen substrates on the growth and polygalacturonase activity of Trichoderma viride (BITRS-1001 isolated from the tar sand deposit in Gbelejuloda-Irele Ondo State, Nigeria were investigated in submerged cultivation at 30 °C ± 2 °C. The commercial carbon and nitrogen substrates included sucrose, fructose, starch, maltose, lactose and peptone, sodium nitrate, urea and casein respectively. All the carbon substrates used supported the growth of T. viride (0.566 to 0.156 g/50 mL of culture medium with starch supporting the highest biomass yield and sucrose the least biomass yield. Maximum polygalacturonase activity of 3033 U/mL was recorded in maltose medium. Maximum biomass yield on the nitrogen sources was observed in the organic nitrogen namely peptone and casein with values not significantly different from each other at p ≤ 0.05. In the determination of the crude enzyme activity on the nitrogen sources, maximum polygalacturonase activity of 12,400 U/mL was recorded in peptone medium. Hence, a careful manipulation of these nutrient substrates could help to optimise the production of this enzyme on a large scale.

  8. Upgrading of hydropyrolysis coal tar by hydroprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Haglund, R.; Otterstedt, J.E.; Sterte, J. (Chalmers Univ. of Tech., Goeteborg (Sweden). 1. Dept. of Engineering Chemistry)

    1991-05-01

    Upgrading of a hydropyrolysis coal tar by hydroprocessing was investigated using different process conditions. The response of the hydropyrolysis tar to hydroprocessing was compared to those of a conventional coal tar and two heavy oil fractions. At comparable conditions, the removal of heteroatoms from the hydropyrolysis tar was more effective than from the conventional tar and, in particular, than from the oil fractions. Using conditions typical for hydroprocessing of heavy oil fractions, the contents of N, O as well as S in the hydropyrolysis tar were reduced by more than 90%. Hydroprocessing also resulted in a considerable increase in the gasoline fraction of the tar. (orig.).

  9. Athabasca tar sands as a source of crude oil

    Energy Technology Data Exchange (ETDEWEB)

    Montgomery, D S

    1964-01-01

    A general review is presented of the variable nature of the Athabasca bituminous sand resource, and the chemical composition of the bitumen is given at various stages during the refining from raw material to finished products. The research conducted at the Mines Branch, Ottawa, on vapor-phase hydrogenation of coker distillates is described, emphasizing the effect of hydrogen pressure on the rate of catalyst deactivation. The quality of the hydrogenated products is described in general terms and some observations are made on the reasons why large-scale operation is essential if an economical process is to be achieved.

  10. Creating a soil-like profile for plant growth using tailings sand and fine tails

    International Nuclear Information System (INIS)

    Li, X.; Fung, M. P. Y.

    1996-01-01

    Development of a technology to create stable aggregates with a soil-like profile capable of supporting a stable plant community, was discussed as the major challenge and primary task in restoring oil sands processing wastes, and in re-creating a self-sustaining ecosystem. A procedure for creating a soil-like profile using oil sands mining wastes, was described. Clay and water content were critical factors in the aggregation procedure. A study to evaluate the physical, chemical and biological properties of these soils and their suitability as a plant growth medium is currently underway. 6 refs., 3 figs

  11. Preliminary study of sand jets in water-capped artificial and real MFT

    Energy Technology Data Exchange (ETDEWEB)

    Cai, J.; Zhu, D.; Rajaratnam, N. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering

    2008-07-01

    A preliminary study of sand jets in water-capped artificial and real MFT was presented. Background information on oil sands tailing reclamation including water capping and sand capping were first discussed, followed by background information to the study, including non-Newtonian fluids and laponite clay, the artificial clay used mainly in small amounts as a rheology modifier in industrial fluids and materials. Although laponite clay is insoluble in water, it hydrates to make a clear and colourless colloidal, which is thixotropic and also behaves as a Bingham plastic fluid. The benefit of using gels made from laponite is the ability to see through to observe the physical processes in it. The objectives of the study were to examine the dynamics of sand jets in water-capped laponite gel and real MFT; improve the understanding of physical processes related to MFT and sand/slurry operations in tailings ponds; and find potential applications in recycling processed water and decommissioning of tailings ponds. It was concluded that it is much more difficult for jets to penetrate water-capped MFT due to larger yield stress in MFT. Future studies will focus on density correction, viscosity adjustment, and sensitivity analysis. tabs., figs.

  12. Providing floating capabilities in latest-generation sand screens

    Energy Technology Data Exchange (ETDEWEB)

    Bowen, E.G.; Coronado, M.P. [Society of Petroleum Engineers, Richardson, TX (United States)]|[Baker Hughes, Houston, TX (United States)

    2008-10-15

    Alternative production methods are needed for the massive reserves located in the bitumen region of Canada's tar sands. The area has over 100 installations of sand screens/slotted liners in both injection and production legs using steam-assisted gravity drainage (SAGD) technology. Multiple wells must be drilled from a single pad because of the sensitive nature of the environment. With significant depths of these wells, a floating sand screen provides assurance that the sand screen will reach the desired depth. Paraffin is generally used to plug the flow access of the screen during installation. This paper discussed a new technology that has been developed to allow for sand screen installations without relying on paraffin wax to withstand differential pressure. The new technology uses a hydro-mechanical valving system incorporated into the screen design to temporarily close off the screen while being run in the hole. The paper described how the technology could provide a reliable, time-saving solution for SAGD installations when floating sand control screens are needed. The paper discussed current technology and its limitations, sand screen installation, screen design for floating applications, and additional applications. It was concluded that this technology solution provides a unique alternative to the methods currently used to install sand screens with SAGD technology in the fast growing Canadian market for bitumen recovery. 2 refs., 5 figs.

  13. Segregation and differential settling in flocculated tailings

    Energy Technology Data Exchange (ETDEWEB)

    Farinato, R.S.; Mahmoudkhani, A.; Fenderson, T.; Watson, P. [Kemira, Atlanta, GA (United States)

    2010-07-01

    Untreated oil sands tailings have a high solids content, have poor dewaterability, and contain no aggregates. This PowerPoint presentation investigated segregation and differential settling in flocculated tailings. Tailings were treated with gypsum and various polymers. Cylinder settling, dynamic rheometry, particle size analysis, and microscopy techniques were used to characterize the composite tailings. The particles sizes of the samples were evaluated in relation to shear rate, bed depth, and treatment. The study showed that the gypsum-treated tailings had small aggregates, size stratification, a high solids content, and poor dewaterability. The polymer N-treated tailings had the lowest solids content, good dewaterability, and weak aggregates. The polymer A-treated tailings had a low solids content, very good dewaterability, and strong aggregates. The addition of a coagulant to the polymer-A treated tailings provided weaker aggregates and a higher solids content. tabs., figs.

  14. Preparation of pure phenols from tars

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, J

    1933-02-07

    A process is disclosed for the preparation of pure phenols from brown coal tar, shale tar, or primary tar, characterized in that the raw oil obtained from the tar is carefully fractionated, in a suitable way without or with a slight pressure decrease, or before the fractionation the raw oil is heated to free the prepared phenolate solution from impurities after successful oxidation by passing in steam at a temperature between 100 and 120/sup 0/C.

  15. Tropospheric Emission Spectrometer (TES) Satellite Validations of Ammonia, Methanol, Formic Acid, and Carbon Monoxide over the Canadian Oil Sands

    Data.gov (United States)

    U.S. Environmental Protection Agency — The URLs link to the data archive of the Troposphere Emission Spectrometer (TES) retrievals. These include the transects included in the Canadian Tar Sands study. A...

  16. Analysis of tars produced in biomass gasification

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, J.; Wang, Y.; Kinoshita, C.M. [Univ. of Hawaii, Honolulu, HI (United States)

    1993-12-31

    Parametric tests on tar formation, varying temperature, equivalence ratio, and residence time, are performed on a bench-scale, indirectly-heated fluidized bed gasifier. Prepared tar samples are analyzed in a gas chromatograph (GC) with a flame ionization detector, using a capillary column. Standards containing dominant tar species have been prepared for GC calibration. The identified peaks include single-ring hydrocarbons, such as benzene, to five-ring hydrocarbons, such as perylene; depending on the gasification conditions, the identified species represent about 70 to 90% (mass basis) of the tar constituents. Under all conditions tested, benzene and naphthalene were the most dominant species. Temperature and equivalence ratio have significant effect on tar yield and tar composition. Tar yield decreases with increasing temperature or equivalence ratio. The test results suggest that lower temperature favors the formation of more aromatic tar species with diversified substituent groups, while higher temperature favors the formation of fewer aromatic tar species without substituent groups. Higher temperature or equivalence ratio favors the formation of polyaromatic compounds. Oxygen-containing compounds exist in significant quantities only at temperature below 800{degrees}C and decrease with increasing temperature, equivalence ratio, or residence time.

  17. Determination of phenol in tar

    Energy Technology Data Exchange (ETDEWEB)

    Dierichs, A; Heinichen, G

    1955-01-01

    During low-temperature carbonization of lignite, the phenols and other oxygenated compounds appear both in the aqueous-process liquor and in the tar. Measurements of these oxygenated components resulting from low-temperature carbonization may serve as a parameter for the classification of lignites. However, such measurements are complicated by the instability of the tar and the complex nature of some of the acidic substances. Difficulties with the previous methods of analysis are reviewed. The present method outlines separation of aqueous-process liquor from lignite tar in a Fischer retort, followed by determination of phenols and fatty acids in the tar phase. The jacketed tar receiver is washed with 300 milliliter xylol and treated with aqueous caustic washes. Neutral oils are separated from the aqueous alkali solution. It is then extracted with ether and finally acidified with HCl. Solids are filtered off, and phenols and fatty acids are separated by Na/sub 2/CO/sub 3/ solution.

  18. Hydroconversion of coal tars: effect of the temperature of pyrolysis on the reactivity of tars

    Energy Technology Data Exchange (ETDEWEB)

    Lemberton, J.L.; Touzeyidio, M.; Guisnet, M.

    1988-12-01

    The hydroconversion of a low-temperature and of a high-temperature tar was carried out in the presence of a sulfided Ni and Mo on alumina catalyst - pure or mixed with an acid catalyst (HY zeolite). Significant amounts of light products can be obtained from low temperature tar, formed however through a non-catalytic process. On the contrary, there is a slight catalytic effect during the hydroprocessing of high temperature tar, but the yield in light products is very low. These results can be explained by an extensive poisoning of the NiMo on alumina catalyst by coke which is initiated by the O- and N-containing compounds of the tars. 10 refs., 1 fig., 3 tabs.

  19. Geophysics comes of age in oil sands development

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, P. [WorleyParsons Komex, Calgary, AB (Canada); Birch, R.; Parker, D.; Andrews, B. [Calgary Univ., AB (Canada). Dept. of Geology and Geophysics

    2008-07-01

    This paper discussed geophysical techniques developed for oil sands exploration and production applications in Alberta's oil sands region. Geophysical methods are playing an important role in mine planning, tailings containment, water supply, and land reclamation activities. Geophysics techniques are used to estimate the volume of muskeg that needs to be stripped and stored for future reclamation activities as well as to site muskeg piles and delineate the thickness of clay Clearwater formations overlying Cretaceous oil-bearing sands. 2-D electrical resistivity mapping is used to map river-connected deep bedrock Pleistocene paleovalleys in the region. Geophysical studies are also used to investigate the interiors of dikes and berms as well as to monitor salt migration within tailings piles. Sonic and density logs are used to create synthetic seismograms for mapping the Devonian surface in the region. The new applications included the calculation of bitumen saturation from surface sands and shales; muskeg thickness mapping; and non-intrusive monitoring of leachate plumes. Geophysical techniques included 2-D electrical resistivity imaging; transient electromagnetic (EM) technologies; ground penetrating radar; and high-resolution seismic reflections. Polarization, surface nuclear magnetic resonance and push-probe sensing techniques were also discussed. Techniques were discussed in relation to Alberta's Athabasca oil sands deposits. 4 refs.

  20. Bacterial reduction of selenium in coal mine tailings pond sediment

    Energy Technology Data Exchange (ETDEWEB)

    Siddique, T.; Arocena, J.M.; Thring, R.W.; Zhang, Y.Q. [University of North British Columbia, Prince George, BC (Canada)

    2007-05-15

    Sediment from a storage facility for coal tailings solids was assessed for its capacity to reduce selenium (Se) by native bacterial community. One Se{sup 6+}-reducing bacterium Enterobacter hormaechei (Tar11) and four Se{sup 4+}-reducing bacteria, Klebsiella pneumoniae (Tar1), Pseudomonasfluorescens (Tar3), Stenotrophomonas maltophilia (Tar6), and Enterobacter amnigenus (Tar8) were isolated from the sediment. Enterobacter horinaechei removed 96% of the added Se{sup 6+} (0.92 mg L{sup -1} from the effluents when Se6+ was determined after 5 d of incubation. Analysis of the red precipitates showed that Se{sup 6+} reduction resulted in the formation of spherical particles ({lt}1.0 {mu} m) of Se 0 as observed under scanning electron microscope (SEM) and confirmed by EDAX. Selenium speciation was performed to examine the fate of the added Se{sup 6+} in the sediment with or without addition of Enterobacter hormaechei cells. More than 99% of the added Se{sup 6+} (about 2.5 mg L{sup -1}) was transformed in the nonsterilized sediment (without Enterobacter hormaechei cells) as well as in the sterilized (heat-killed) sediment (with Enterobacter hormaechei cells). The results of this study suggest that the lagoon sediments at the mine site harbor Se{sup 6+}- and Se{sup 4+} -reducing bacteria and may be important sinks for soluble Se (Se{sup 6+} and Se{sup 4+}). Enterobacter hormaechei isolated from metal-contaminated sediment may have potential application in removing Se from industrial effluents.

  1. Dehydration of hydrated low-temperature tar

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, T

    1949-01-01

    Yoshida examined the mechanism of the dehydration of hydrated low-temperature tar with a microscope. The tar containing free carbon and coal dust is so stable that the removal of the above substances and water by a physical method is very difficult. Addition of light oil produced by fractionation of low-temperature tar facilitates the operations. Yoshida tried using the separate acid, neutral, and basic components of the light oil; the acid oil proved to be most effective. For many reasons it is convenient to use light oil as it is. In this method the quantity of light oil required is 2 to 3 times that of tar. But in supplementing the centrifugal method, the quantity of light oil needed might be only half the amount of tar.

  2. Separating cresote from tars, mineral oils, etc

    Energy Technology Data Exchange (ETDEWEB)

    Erdmann, E

    1921-01-07

    Phenolic bodies are extracted from tars such as lignite, shale, peat, coal, producer and low temperature tars, and from tar distillates and residues and from mineral oils and distillates by washing with a mixture of acetone and water. Acetone extracts of the tars etc., may be mixed with water or aqueous acetone to cause the separation of the oils, while the creosote remains in solution.

  3. Process water treatment in Canada's oil sands industry : 1 : target pollutants and treatment objectives

    International Nuclear Information System (INIS)

    Allen, E.W.

    2008-01-01

    The continuous recycling of tailings pond water in the oil sands industry has contributed to an overall decline in water quality used for bitumen recovery, general water consumption, and remedial activities. This paper reviewed process water quality and toxicity data from 2 long-term oil sands operations. The aim of the study was to determine potential roles for water treatment and provide benchmarks for the selection of candidate water treatment technologies in the oil sands region of Alberta. An overview of the oil sands industry was provided as well as details of bitumen recovery processes. The study examined target pollutants and exceedances identified in environmental and industrial water quality guidelines. The study demonstrated that the salinity of tailings pond water increased at a rate of 75 mg per litre per year between 1980 and 2001. Increases in hardness, chloride, ammonia, and sulphates were also noted. Naphthenic acids released during bitumen extraction activities were determined as the primary cause of tailings pond water toxicity. A summary of recent studies on experimental reclamation ponds and treatment wetlands in the oil sands region was included. 19 refs., 4 tabs., 11 figs

  4. Heat-resistant agent used for control sand of steam huff and puff heavy oil well

    Science.gov (United States)

    Zhang, F. S.; Liu, G. L.; Lu, Y. J.; Xiong, X. C.; Ma, J. H.; Su, H. M.

    2018-01-01

    Heat-resistant agent containing hydroxymethyl group was synthesized from coal tar, which has similar structure with phenolic resin and could improve the heat resistance of phenolic resin sand control agent. The results showed that the heat resistance of the sand control agent was improved by adding 10% to 30% heat-resistant agent, after 280°C high temperature treatment for 7d, the compressive strength of consolidated core was increased to more than 5MPa. The compressive strength of consolidation core was not decreased after immersion in formation water, crude oil, acid or alkaline medium, which showed good resistance to medium immersion. The sand control agent had small core damage and the core permeability damage ratio of sand control agent consolidation was only 18.7%.

  5. Suitability of iron ore tailings and quarry dust as fine aggregates for ...

    African Journals Online (AJOL)

    Eight concrete mixes were produced with different levels of sand replacement by either iron ore tailings or quarry dust, while the ninth mix of 100 % river sand served as the control. The highest 28-day compressive strength of 29.2 N/mm2 was obtained by blending 75 % sand and 25 % quarry dust with cement, which was 7 ...

  6. Ethoxyresorufin-O-deethylase (EROD) induction in rainbow trout exposed to diluted oil sand wastewater

    International Nuclear Information System (INIS)

    Verbeek, A.; Mackay, W.; Birkholz, D.

    1995-01-01

    Toxic industrial wastewaters, such as those from oil sands extraction, must be assessed for their potential sublethal effects before they can be safely disposed in the environment. The induction of ethoxyresorufin-O-deethylase activity was assessed as a potential bioindicator of sublethal stress in rainbow trout exposed to sublethal concentrations of oil sands tailings water. The mixed-function oxygenase system in rainbow trout responded rapidly following a definable concentration-response relationship; however, it proved to be a relatively insensitive indicator of sublethal exposure to oil sands tailings water. Increased activity and maximal induction, as a result of exposure to 0.3 and 0.6 times the LC 50 (Toxic Units), occurred rapidly within 24 hours of exposure. The linearity of the relationship between the concentration of oil sands tailings pond water and ethoxyresorufin-O-deethylase activity, expressed by the following regression equation, In EROD = 3.68 (conc.) + 3.20, had an r 2 value of 0.593. Maximal induction required 0.4--0.8 Toxic Units. The absolute level of maximal induction was only one-fifth to one-sixth of the potential induction as found in response to the positive control, 0.5 mg/kg β-naphthoflavone (i.p.). The authors also present data that suggests that the different levels of induction observed in trout exposed to tailings pond water vs those injected with 0.5 mg/kg β-naphthoflavone (i.p.) may be indicative of two different P450 isoforms, the CYP4Al isoform responding to the organic acidic surfactants in oil sands tailings pond water and the CYP1A1 isoform, the isoform generally associated with most xenobiotic transformation in fish, responding to β-naphthoflavone

  7. Bioremediation potential of coal-tar-oil-contaminated soil

    International Nuclear Information System (INIS)

    Lajoie, C.A.

    1991-01-01

    The bioremediation of coal tar oil contaminated soil was investigated in 90 day laboratory simulation experiments. The effect of soil moisture, humic acid amendment, and coal tar oil concentration on the rate of disappearance of individual coal tar oil constituents (PAHs and related compounds) was determined by methylene chloride extraction and gas chromatography. Mass balance experiments determined the fate of both the individual 14 C-labeled PAHs phenanthrene, pyrene, and benzo(a)pyrene, and the total coal tar oil carbon. Mineralization, volatilization, incorporation into microbial biomass, disappearance of individual coal tar oil constitutents, and the distribution of residual 14 C-activity in different soil fractions were measured. The rate of disappearance of coal tar oil constituents increased with increasing soil moisture over the experimental range. Humic acid amendment initially enhanced the rate of disappearance, but decreased the extent of disappearance. The amount of contamination removed decreased at higher coal tar oil concentrations. The practical limit for biodegradation in the system tested appeared to be between 1.0 and 2.5% coal tar oil. Mineralization accounted for 40 to 50% of the applied coal tar oil. Volatilization was a minor pathway of disappearance

  8. Radon diffusion in candidate soils for covering uranium mill tailings

    International Nuclear Information System (INIS)

    Silker, W.B.; Kalkwarf, D.R.

    1983-04-01

    Diffusion coefficients were measured for radon in 34 soils that had been identified by mill personnel as candidate covers for their tailings piles in order to reduce radon emission. These coefficients referred to diffusion in the total pore space of the soils. They were measured in the laboratory by a steady-state method using soil columns compacted to greater than 80% of their Proctor maximum packing densities but with moisture contents generally less than would be expected at a tailings site. An empirical equation was used to extrapolate measured coefficients to value expected at soil-moisture contents representative of tailings sites in the western United States. Extrapolated values for silty sands and clayey sands ranged from 0.004 to 0.06 cm 2 /s. Values for inorganic silts and clays ranged from 0.001 to 0.02 cm 2 /s

  9. The use of stable isotopes to trace oil sands constituents

    International Nuclear Information System (INIS)

    Farwell, A.J.; Nero, V.; Dixon, D.G.

    2002-01-01

    A study was conducted to determine the biological effects of oil sands mining operations on aquatic ecosystems. The study focused on the Athabasca oil sand deposit, the largest of 4 deposits in northern Alberta. In particular, the study examined the cycling of oil sand constituents in Benthic invertebrates collected from test pits at Syncrude Canada Ltd.. The invertebrates were similar in size, but different in the quantity of process-affected water or mature fine tailings containing residual bitumen. Dragonflies and damselflies in particular, showed trends of depletion for the carbon 13 isotope and enrichment in nitrogen 15 isotope in pits where levels of process affected water was high. The depletion of carbon 13 isotope suggests that oil sand constituents assimilate into the benthic food chain. The greatest carbon 13 depletion, which was approximately 27 per cent, was found to be in test pits with high turbidity. This implies that oil sands constituents degrade microbially instead of by photosynthetic production. All benthic invertebrate group demonstrated an incremental enrichment in nitrogen 15 isotope from the control pit to the pit with greatest levels of mature fine tailings

  10. Problems in the separation of radium from uranium ore tailings

    Energy Technology Data Exchange (ETDEWEB)

    Seeley, F.G.

    1976-01-01

    The radium content of a representative sandstone type of uranium ore was found to be distributed uniformly according to particle size before leaching, but in sulfuric acid-leached tailings was found predominantly in the -325 mesh fraction. The radium leaching characteristics from both ore and sulfate-leached tailings were investigated. Several 1 M salt solutions showed poor to moderate RaSO/sub 4/ dissolution from ''slimes solids'' tailings, while 3 M HNO/sub 3/ or HCl solutions dissolved approximately 95% of the radium content of either ore or tailings. Tests are reported in which -325 mesh sand particles were coated with alkaline-earth sulfates by a special technique to simulate slime solids tailings. The dissolution of RaSO/sub 4/ from these coated sands was decreased by the presence of BaSO/sub 4/, but increased by the presence of CaSO/sub 4/. The interrelationships in the dissolution of mixtures of CaSO/sub 5/, SrSO/sub 4/, BaSO/sub 4/, and RaSO/sub 4/ are shown, and a generalized equation for the estimation of the dissolution of a minor component is presented.

  11. Literature search on the environmental impacts of tar sands operations

    International Nuclear Information System (INIS)

    Birkholz, D.; Prendergast, S.

    1990-09-01

    An extensive review is presented of the literature on the chemistry and biological impacts of current and potential effluents and discharges from oil sands plants on the Athabasca River. The pollutant compounds of interest included polycyclic aromatic hydrocarbons, methyl homologues and metabolites, polycyclic aromatic sulfur heterocycles, polycyclic aromatic nitrogen heterocycles, and naphthenic acids. Topics of interest include chemical methods for identifying and quantitating the above compounds and their metabolites, their sources and release rates, their toxicity to native fish of the Athabasca system, and their degradation in the natural environment. 376 refs., 4 figs., 26 tabs

  12. Radon emanation characteristics of uranium mill tailings

    International Nuclear Information System (INIS)

    Nielson, K.K.; Freeman, H.D.; Hartley, J.N.; Mauch, M.L.; Rogers, V.C.

    1982-01-01

    Radon emanation from uranium mill tailings was examined with respect to the mechanisms of emanation and the physical properties of the tailings which affect emanation. Radon emanation coefficients were measured at ambient moisture on 135 samples from the 1981 field test site at the Grand Junction tailings pile. These coefficients showed a similar trend with moisture to those observed previously with uranium ores, and averaged 0.10 + or - 0.02 at dryness and 0.38 + or - 0.04 for all samples having greater than five weight-percent moisture. Small differences were noted between the maximum values of the coefficients for the sand and slime fractions of the tailings. Separate measurements on tailings from the Vitro tailings pile exhibited much lower emanation coefficients for moist samples, and similar coefficients for dry samples. Alternative emanation measurement techniques were examined and procedures are recommended for use in future work

  13. Architecture and environmental restoration: Remediating uranium mill tailings from buildings

    International Nuclear Information System (INIS)

    Teply, J.D.

    1991-01-01

    The US Department of Energy (DOE) Grand Junction Projects Office (GJPO) manages the Uranium Mill Tailings Remedial Action (UMTRA) Program in Grand Junction, Colorado. This program is a congressionally mandated clean up of by-product waste that resulted from the extraction of yellow cake from uranium ore. The by-product waste, a fine sand commonly called open-quotes mill tailingclose quotes is contaminated with low-level radioactivity. These mill tailings were available to the community for use as construction material from approximately 1952 to 1966; their use as bedding material for concrete slabs, utilities, backfill materials, concrete sand, and mortar created unique remediation problems that required innovative solutions. This paper describes how design personnel approach the remediation of structures, the evaluation of the buildings, and the factors that must be considered in completing the remediation design. This paper will not address the health risks of the tailings in an inhabited space, the remediation of exterior areas, or the process of determining where the tailings exist in the building

  14. Process and apparatus for recovering of oil, bitumen, tar, resins, etc

    Energy Technology Data Exchange (ETDEWEB)

    1921-11-06

    A process for recovering oil, bitumen, tar, and resins from oil shale, oil sands, Fuller's earth, peat, brown coal, mineral coal, and wood, through direct action of superheated steam on the material, is characterized by the fact that superheated steam with or without mixing of inert gases at a temperature, which lies below the decomposition temperature of the material being treated, is passed through the material with a high velocity. It leaves through nozzles, used in steam turbines. A method of carrying out the process in which solution medium is used for action on the material is characterized by the fact that solvents such as benzine and benzol are mixed with steam in different quantities.

  15. Centrifuge treatment of coal tar

    Energy Technology Data Exchange (ETDEWEB)

    L.A. Kazak; V.Z. Kaidalov; L.F. Syrova; O.S. Miroshnichenko; A.S. Minakov [Giprokoks, the State Institute for the Design of Coke-Industry Enterprises, Kharkov (Ukraine)

    2009-07-15

    New technology is required for the removal of water and heavy fractions from regular coal tar. Centrifuges offer the best option. Purification of coal tar by means of centrifuges at OAO NLMK permits the production of pitch coke or electrode pitch that complies with current standards.

  16. Gasification of oil sand coke: review

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E. [IMAF Group, Ottawa, ON (Canada)

    1998-08-01

    The production of synthetic crude from the tar sands in Western Canada has been steadily increasing. Most of the delayed coke produced by Suncor is combusted on site, whereas all fluid coke produced by Syncrude is stockpiled.The database on the chemical and physical properties of the oil sand coke, including the composition and fusion properties of the mineral matter, has been established. The reactivity of the coke was determined by oxygen chemisorption, fixed bed and fluid bed bench scale gasification and pilot plant gasification. The reactivity of the oil sand coke for gasification is rather low and comparable to high rank coals, such as anthracite. Slurrability tests revealed that a solid concentration in water, approaching 70 wt%, can be achieved. Gasification is the front runner among clean technologies for the conversion of carbonaceous solids to useful products. Several commercial gasifiers are available to cover the wide range of severity. Because of the low reactivity of oil sands coke, high severity conditions are required to achieve high gasification conversion. Such conditions can be attained in entrained bed gasifiers. Gasifiers employing both dry and slurry feeding systems are suitable. A high efficiency, low SO{sub x} and NO{sub x} emissions, as well as a low solid waste production are among the key advantages of the gasification technology compared with thecompeting technologies. Commercial gasification of oil sands coke is delayed because of the availability of natural gas on the site of the upgrading plants. Potential for the transportation of the oil sand coke to USA for electricity generation using the integrated gasification combined-cycle (IGCC) technology was evaluated. 27 refs., 17 figs., 9 tabs.

  17. Coal tar pitch. Interrelations between properties and utilization of coal tar pitch

    Energy Technology Data Exchange (ETDEWEB)

    Collin, G; Koehler, H [Ruetgerswerke A.G., Duisburg (Germany, F.R.)

    1977-06-01

    Coal tar pitch is won as a highly aromatic, thermoplastic residue by destillating coal tar. In this paper the structure as well as the chemical and physical data of this pitch are introduced. In addition to this the actual as well as possible applications are indicated. For example, the pitch can be used for the production of binders, e.g. for electrodes and road construction as well as in combination with plastics for the production of insulating material and corrosion protection material.

  18. Coal tar: past, present and future

    Energy Technology Data Exchange (ETDEWEB)

    Thami, G.P.; Sarkar, R. [Government Medical College & Hospital, Chandigarh (India). Dept. of Dermatology & Venerology

    2002-03-01

    Crude coal tar has been used in the treatment of dermatoses for many decades. In the last few years its use has been limited to skin diseases such as psoriasis and chronic dermatitis. Newer topical modalities for psoriasis are being used increasingly for treatment, but have failed to replace crude coal tar as a first-line treatment of psoriasis. The authors review the pharmacology, chemistry and use of crude coal tar in order to reappraise its role as a therapeutic agent in dermatology.

  19. Distillation of tar and tar fractions in the presence of surface-active coke

    Energy Technology Data Exchange (ETDEWEB)

    Jaeppelt, A; Klaus, J

    1943-01-01

    The tar obtained by low-temperature carbonization of Upper Silesian gas coke and fractions from this tar were distilled in the presence of different grades of coke dust with varying surface activity; the coke had been activated by steam in the course of its production by low-temperature carbonization. The surface activity of the coke dusts was measured by determining the heat of wetting with C/sub 6/H/sub 6/. Tar and coke dust, both anhydrous, were mixed in a kneading machine in such proportions that the capillaries of the dust were saturated and enough ''externally'' bound tar was present to permit briquetting. The briquets were distilled without cracking and with steam as heating medium. The yield and quality of the distillate depended on the magnitude of the internal surface of the coke dust used; a mixture of a very active coke from brown coal and tar yielded a distillate with Conradson carbon residue of 1.34 percent, asphalt content 6.1 percent and eta/sub 20/ 5.4/sup 0/ E. as compared with C residue of 10.95 percent, asphalt content 33.5 percent and eta/sub 20/ 123.6/sup 0/ E. of the distillate obtained in the absence of surface-active coke. Even higher-boiling fractions can be improved by this treatment, although it is preferable to use oils with an initial boiling point below 300/sup 0/. The ratio of oil to adsorbent is not critical, but better results were obtained with higher percentages of added coke dust. The process in its present form is not suited for the conversion of crude creosote to useful phenols.

  20. Microbial activities and communities in oil sands tailings ponds

    Energy Technology Data Exchange (ETDEWEB)

    Gieg, Lisa; Ramos, Esther; Clothier, Lindsay; Bordenave, Sylvain; Lin, Shiping; Voordouw, Gerrit; Dong, Xiaoli; Sensen, Christoph [University of Calgary (Canada)

    2011-07-01

    This paper discusses how the microbial communities and their activity play a vital role in tailings ponds. The ponds contain microorganisms along with metals, hydrocarbon diluent, naphthenic acid and others. The ponds play an important role in mining operations because they store bitumen extraction waste and also allow water to be re-used in the bitumen extraction process. Pond management presents a few challenges that include, among others, gas emissions and the presence of toxic and corrosive acids. Microbial activities and communities help in managing these ponds. Microbial activity measurement in active and inactive ponds is described and analyzed and the results are presented. The conditions for reducing sulfate, nitrate and iron are also presented. From the results it can be concluded that naphthenic acids can potentially serve as substrates for anaerobic populations in tailings ponds.

  1. How confident is Fort McKay that industry can reclaim oil sand development

    Energy Technology Data Exchange (ETDEWEB)

    Fitzpatrick, C. [Fort McKay First Nations, AB (Canada)

    2004-02-05

    This presentation described how traditional environmental knowledge (TEK) can provide valuable information for both the reclamation design and assessment of oil sand development in Fort McKay. Conservation is valued by the Fort McKay First Nations communities who claim that current reclamation methods are too slow, and that the land is not being brought back to its original use with the uniqueness of the boreal landscape. Elders have noted that each year the water level in the Athabasca River is lower. The blowing tailings and coke dust are causing trees to dye and driving animals away. There is concern that the animals that remain may not be safe to eat. The Fort McKay First Nation community has stated that it will view reclamation as a success only when it functions with proof over many generations. The major concerns include: salt in the water draining from reclaimed areas; salt in the soils of reclaimed area; muskeg cannot be recreated; and, the issue of whether cranberry, blueberry and streambank forest areas can be recreated, along with traditional medicinal plants. Other concerns include the loss of rivers such as the Beaver Creek and Tar River, and that the water in reclaimed areas may not be suitable for animals to live in or to drink. tabs., figs.

  2. How confident is Fort McKay that industry can reclaim oil sand development

    International Nuclear Information System (INIS)

    Fitzpatrick, C.

    2004-01-01

    This presentation described how traditional environmental knowledge (TEK) can provide valuable information for both the reclamation design and assessment of oil sand development in Fort McKay. Conservation is valued by the Fort McKay First Nations communities who claim that current reclamation methods are too slow, and that the land is not being brought back to its original use with the uniqueness of the boreal landscape. Elders have noted that each year the water level in the Athabasca River is lower. The blowing tailings and coke dust are causing trees to dye and driving animals away. There is concern that the animals that remain may not be safe to eat. The Fort McKay First Nation community has stated that it will view reclamation as a success only when it functions with proof over many generations. The major concerns include: salt in the water draining from reclaimed areas; salt in the soils of reclaimed area; muskeg cannot be recreated; and, the issue of whether cranberry, blueberry and streambank forest areas can be recreated, along with traditional medicinal plants. Other concerns include the loss of rivers such as the Beaver Creek and Tar River, and that the water in reclaimed areas may not be suitable for animals to live in or to drink. tabs., figs

  3. Flash hydropyrolysis of bituminous coal . III. Research on flash hydropyrolysis tar

    Energy Technology Data Exchange (ETDEWEB)

    Dong, M.; Zhu, Z.; He, Y.; Ding, N.; Tang, L. [East China University of Science and Technology, Shanghai (China)

    2000-02-01

    Tar sample obtained by flash hydropyrolysis (FHP) from Dongshen coal at high pressure entrained reactor was investigated. An effect of flash hydropyrolysis temperature on the main components in tar was studied and the quality of the tar was compared with high temperature coke oven tar. The results showed that: the yields of liquid hydrocarbon in FHP tar were more than 15%, which is twofold of that in coke oven tar; the FHP tar has high oil fraction and low pitch; high phenol components and pure condensed polycyclic aromatic hydrocarbon, and low aliphatic hydrocarbon. The components of the FHP tar were simpler than that of high temperature coke oven tar. Therefore, FHP has improved the quantity and quality of tar. 11 refs., 3 figs., 5 tabs.

  4. Toad in the hole : Suncor finds amphibious life at tailings ponds

    Energy Technology Data Exchange (ETDEWEB)

    Jaremko, D.

    2004-08-02

    Suncor, a giant oilsands operator, has discovered Canadian toads in five of its nine tailings ponds surveyed in 2002. The numbers are greater than any recorded in the boreal forests. Most are living in a dike along the company's oldest tailings pond which include slurries of sand, water, clay, residual bitumen and chemicals left from oilsands production. Reclamation efforts have involved emptying the tailings and filling the area with sand to create a combination of wet and dry lands. The presence of Canadian toads is a good indicator of environmental health. In the late 1990s, the species was among those listed at risk of declining levels. It is believed that the sandy soil layers in the reclamation ponds are ideal for toad hibernation. Suncor and Golder and Associations are currently examining the feasibility of having the reclaimed areas become future restorations of toad habitat.

  5. Physical and performance properties of coal tar urethanes - pipe

    International Nuclear Information System (INIS)

    Hickney, J.; Hendry, M.

    1984-01-01

    The purpose of this paper is to review certain physical properties of coal tar extended urethane coatings designed specifically for use in the pipe coatings market. The blend of coal tar and urethane resins provides a novel finished product with properties cumulatively inherent in its constituents. Typically, coal tar and coal tar pitch offer exceptional water resistance and cathodic alkali resistance when blended with other resins. An example is the standard coal tar epoxies used for many years in the marine markets for shipbottoms

  6. Characterization of acid tar waste from benzol purification | Danha ...

    African Journals Online (AJOL)

    The use of concentrated sulphuric acid to purify benzene, toluene and xylene produces acidic waste known as acid tar. The characterization of the acid tar to determine the composition and physical properties to device a way to use the waste was done. There were three acid tars two from benzene (B acid tar), toluene and ...

  7. The temporal relationship between advertising and sales of low-tar cigarettes.

    Science.gov (United States)

    Reed, Mark B; Anderson, Christy M; Burns, David M

    2006-12-01

    To determine whether a temporal relationship exists between the advertising and sales of low-tar cigarettes. It was hypothesised that increases in the advertising of low-tar cigarettes would precede increases in sales for these cigarettes. The themes of cigarette advertisements were reviewed and coded for 20 low-tar cigarette brands advertised in 13 widely read magazines in the US between 1960 and 1996. These 20 brands represented most of the low-tar cigarette advertisements and cigarette sales from 1967 to 1996. Cigarette sales data were obtained from the 1994 Maxwell report that summarises all cigarette sales from 1925 to 1990. If the advertisement referred to the low-tar attributes of the cigarette advertised, the advertisement was coded as having a low-tar theme and was included in the analysis. Five different graphical presentations of the relationship between the advertising and sales of the 20 low-tar cigarette brands showed a temporal relationship between low-tar advertising and sales for these brands. This relationship was observed for brands that introduced a low-tar alternative into an existing brand family (eg, Marlboro Light) and for new exclusively low-tar brands (eg, Carlton). Despite large increases in the advertising for the exclusively low-tar brands, sales of these brands remained low relative to sales of the low-tar alternative brands. Increases in print advertising of 20 of the most popular low-tar cigarette brands were followed by increases in sales for these cigarettes. Despite increases in the advertising of exclusively low-tar brands in the mid-1970s and early 1980s, the sales of these brands never matched the sales of the low-tar alternative brands. This suggests that it may have been easier to get smokers to switch to low-tar brands within a brand family compared with entirely new low-tar brands. Over the past 30 years, the marketing of low-tar cigarettes as a healthier alternative to higher-tar cigarettes has resulted in these brands

  8. Cancer fear over coal tar products

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-01-01

    Discusses a report by Dutch researchers which suggests that the regular use of coal tar shampoos may significantly increase the risk of cancer due to the high levels of polynuclear aromatic hydrocarbons (PAHs) in the products. The PAH exposure of volunteers using a coal tar anti-dandruff shampoo was studied by measuring the amount of hydroxypyrene, a PAH breakdown product in their urine. Volunteers who had used the shampoo excreted high levels of hydroxypyrene the day after exposure. Excretion by the control group using a non-coal tar anti-dandruff shampoo remained constant. 1 ref., 1 fig.

  9. A Conceptual Cost Benefit Analysis of Tailings Matrices Use in Construction Applications

    Directory of Open Access Journals (Sweden)

    Mahmood Ali A.

    2016-01-01

    Full Text Available As part of a comprehensive research program, new tailings matrices are formulated of combinations of tailings and binder materials. The research program encompasses experimental and numerical analysis of the tailings matrices to investigate the feasibility of using them as construction materials in cold climates. This paper discusses a conceptual cost benefit analysis for the use of these new materials. It is shown here that the financial benefits of using the proposed new tailings matrices in terms of environmental sustainability are much higher when compared to normal sand matrices.

  10. The effect of flocculant on the geotechnical properties of mature fine tailings : An experimental study

    NARCIS (Netherlands)

    Yao, Y.; Van Tol, A.F.; Van Paassen, L.A.

    2012-01-01

    When oil sands tailings are deposited in a tailing pond, they settle and segregate to create a layer of stagnant water on top that is reused in oil extraction and a dense mixture of clay, silt and water on the bottom which is referred to as mature fine tailings (MFT). Dewatering of MFT is a problem

  11. Uranium mill tailings conditioning technology

    International Nuclear Information System (INIS)

    Dreesen, D.R.; Cokal, E.J.; Wangen, L.E.; Williams, J.M.; O'Brien, P.D.; Thode, E.F.

    1982-01-01

    Conditioning of uranium mill tailings involves the physicochemical alteration of tailings to remove or immobilize mobile radionuclides and toxic trace elements before disposal in a repository. The principal immobilization approach under investigation is sintering tailings at high temperatures (1100-1200 deg. C) to radically alter the structure of tailings. This thermal stabilization at 1200 deg. C reduced radon emanation power for tailings sands by factors of 20 to 200 and for tailings fines by factors of 300 to 1100. Substantial reductions in the leachability of most contaminants have been found for thermally conditioned tailings. Obvious mineral transformations occur, including an increase in amorphous material, the conversion of gypsum to anhydrite and its subsequent decomposition, the disappearance of clay minerals, and some decrease in quartz content. A conceptual thermal stabilization process has been developed wherein obsolete coal-fired rotary cement kilns perform the sintering. An economic analysis of this conceptual process has shown that thermal stabilization can be competitive at certain tailings sites with other remedial actions requiring the excavation, transportation, and burial of tailings in a repository. An analysis of the long-term radiological hazard posed by untreated tailings and by tailings conditioned by radionuclide removal has illustrated the necessity of extracting both 226 Ra and 230 Th to achieve long-term hazard reductions. Sulphuric acid extraction of residual mineral values and important radionuclides from tailings has been investigated. Concentrated H 2 SO 4 can extract up to 80% of the 226 Ra, 70% of the Ba, and 90% of the 230 Th from tailings in a single stage extraction. An economic analysis of a sulphuric acid leach process was made to determine whether the value of minerals recovered from tailings would offset the leaching cost. For one relatively mineral-rich tailings pile, the U and V values would more than pay for the

  12. The temporal relationship between advertising and sales of low‐tar cigarettes

    Science.gov (United States)

    Reed, Mark B; Anderson, Christy M; Burns, David M

    2006-01-01

    Objective and hypothesis To determine whether a temporal relationship exists between the advertising and sales of low‐tar cigarettes. It was hypothesised that increases in the advertising of low‐tar cigarettes would precede increases in sales for these cigarettes. Methods The themes of cigarette advertisements were reviewed and coded for 20 low‐tar cigarette brands advertised in 13 widely read magazines in the US between 1960 and 1996. These 20 brands represented most of the low‐tar cigarette advertisements and cigarette sales from 1967 to 1996. Cigarette sales data were obtained from the 1994 Maxwell report that summarises all cigarette sales from 1925 to 1990. If the advertisement referred to the low‐tar attributes of the cigarette advertised, the advertisement was coded as having a low‐tar theme and was included in the analysis. Results Five different graphical presentations of the relationship between the advertising and sales of the 20 low‐tar cigarette brands showed a temporal relationship between low‐tar advertising and sales for these brands. This relationship was observed for brands that introduced a low‐tar alternative into an existing brand family (eg, Marlboro Light) and for new exclusively low‐tar brands (eg, Carlton). Despite large increases in the advertising for the exclusively low‐tar brands, sales of these brands remained low relative to sales of the low‐tar alternative brands. Conclusions Increases in print advertising of 20 of the most popular low‐tar cigarette brands were followed by increases in sales for these cigarettes. Despite increases in the advertising of exclusively low‐tar brands in the mid‐1970s and early 1980s, the sales of these brands never matched the sales of the low‐tar alternative brands. This suggests that it may have been easier to get smokers to switch to low‐tar brands within a brand family compared with entirely new low‐tar brands. Over the past 30 years, the marketing of low‐tar

  13. The extraction of bitumen from western oil sands. Annual report, July 1991--July 1992

    Energy Technology Data Exchange (ETDEWEB)

    Oblad, A.G.; Bunger, J.W.; Dahlstrom, D.A.; Deo, M.D.; Hanson, F.V.; Miller, J.D.; Seader, J.D.

    1992-08-01

    The University of Utah tar sand research and development program is concerned with research and development on Utah is extensive oil sands deposits. The program has been intended to develop a scientific and technological base required for eventual commercial recovery of the heavy oils from oil sands and processing these oils to produce synthetic crude oil and other products such as asphalt. The overall program is based on mining the oil sand, processing the mined sand to recover the heavy oils and upgrading them to products. Multiple deposits are being investigated since it is believed that a large scale (approximately 20,000 bbl/day) plant would require the use of resources from more than one deposit. The tasks or projects in the program are organized according to the following classification: Recovery technologies which includes thermal recovery methods, water extraction methods, and solvent extraction methods; upgrading and processing technologies which covers hydrotreating, hydrocracking, and hydropyrolysis; solvent extraction; production of specialty products; and environmental aspects of the production and processing technologies. These tasks are covered in this report.

  14. Structure and Mechanism of Staphylococcus aureus TarS, the Wall Teichoic Acid β-glycosyltransferase Involved in Methicillin Resistance.

    Directory of Open Access Journals (Sweden)

    Solmaz Sobhanifar

    2016-12-01

    Full Text Available In recent years, there has been a growing interest in teichoic acids as targets for antibiotic drug design against major clinical pathogens such as Staphylococcus aureus, reflecting the disquieting increase in antibiotic resistance and the historical success of bacterial cell wall components as drug targets. It is now becoming clear that β-O-GlcNAcylation of S. aureus wall teichoic acids plays a major role in both pathogenicity and antibiotic resistance. Here we present the first structure of S. aureus TarS, the enzyme responsible for polyribitol phosphate β-O-GlcNAcylation. Using a divide and conquer strategy, we obtained crystal structures of various TarS constructs, mapping high resolution overlapping N-terminal and C-terminal structures onto a lower resolution full-length structure that resulted in a high resolution view of the entire enzyme. Using the N-terminal structure that encapsulates the catalytic domain, we furthermore captured several snapshots of TarS, including the native structure, the UDP-GlcNAc donor complex, and the UDP product complex. These structures along with structure-guided mutants allowed us to elucidate various catalytic features and identify key active site residues and catalytic loop rearrangements that provide a valuable platform for anti-MRSA drug design. We furthermore observed for the first time the presence of a trimerization domain composed of stacked carbohydrate binding modules, commonly observed in starch active enzymes, but adapted here for a poly sugar-phosphate glycosyltransferase.

  15. Transport and Deposition of Suspended Soil-Colloids in Saturated Sand Columns

    DEFF Research Database (Denmark)

    Sharma, Anu; Kawamoto, Ken; Møldrup, Per

    2011-01-01

    Understanding colloid mobilization, transport and deposition in the subsurface is a prerequisite for predicting colloid‐facilitated transport of strongly adsorbing contaminants and further developing remedial activities. This study investigated the transport behavior of soil‐colloids extracted from...... caused tailing of colloid BTCs with higher reversible entrapment and release of colloids than high flow velocity. The finer Toyoura sand retained more colloids than the coarser Narita sand at low pH conditions. The deposition profile and particle size distribution of colloids in the Toyoura sand clearly...

  16. Characterization of Tar Deposits, Extraction and Sorption Properties

    Directory of Open Access Journals (Sweden)

    Pryszcz Adrian

    2016-06-01

    Full Text Available The main goal of this paper was to characterize and find a useful solution for the decomposition of tar deposits. For the experimental part, tar deposits, formed by polymerization and condensation reactions, were chosen from a storage tank for tars. At first the initial analyses of tar deposits (elemental, thermogravimetric, and calorimetric analyses were performed. After the characterization, the tar deposits were extracted in the Soxhlet extractor by acetone, toluene, and quinolone and activated with potassium hydroxide. As the final step of this work, the sorption characterization on the 3Flex Surface Characterization Analyzer (Micromeritics was performed. The specific surface area of the samples was evaluated using two methods - a single point measurement at p/p0=0.2 and BET method. Micropore and external surface areas were calculated based on a t-plot analysis (carbon black model.

  17. A review of methods developed to solve the issue of weak mature fine tailings

    Energy Technology Data Exchange (ETDEWEB)

    Long, M.; Ulrich, A.; Sego, D. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering

    2010-07-01

    This PowerPoint presentation discussed new techniques for managing weak mature fine tailings (MFT) produced during the oil sands refining process. The techniques included non-segregating tailings, freeze-thaw dewatering, atmospheric drying, and dewatering by vegetation. MFT are produced after water from oil sands slurries is decanted. MFT contain a complex chemical interaction of clays and hydrocarbons. A large proportion of the solids in MFTs are clay minerals and clay-sized. MFTs have low rates of sedimentation and consolidation, and a low bearing capacity and shear strength with high compressibility. MFTs cannot physically support remediation activities, and must be stored in an impounded area. More aggressive dewatering and stabilization processes are required for MFTs. Atmospheric drying involves the deposition of tailings in order to evaporate water. Thin- and thick-lift deposition schemes are used. Atmospheric drying is often complicated by the formation of a bitumen skin over the tailings. Various case studies were presented. Space requirements and issues related to clay content were reviewed. tabs., figs.

  18. An introduction to conservation and reclamation at Alberta's mineable oil sands

    Energy Technology Data Exchange (ETDEWEB)

    Richens, T. [Alberta Environment, Edmonton, AB (Canada)

    2009-07-01

    This paper presented a balanced view of the conservation and reclamation issues and challenges facing oil sands development in Alberta. Bitumen is recovered by truck and shovel in the shallow oil sands of the Athabasca region. The deeper deposits in the Athabasca, Peace River and Cold Lake regions are accessed primarily using a system of horizontal wells and steam to extract the bitumen from the sand and pump it to the surface. Individual in-situ operations have a smaller environmental impact than mines, and do not produce tailings ponds. However, the footprint of in-situ facilities will accumulate over time because of the potential for extensive future development. The key issues facing conservation and reclamation in the mineable oil sands were discussed. Summary statistics on land disturbed and reclaimed in the region were also provided. The challenges facing reclamation activities include long timeframes; large scale, regional planning and integration; competing land use goals; revegetation; byproduct management; and tailings and process-affected water. Multi-stakeholder forums have proven to be the key to the progression of monitoring, research and development and the sharing of knowledge and information. Frameworks have been developed for the assessment of pre-disturbed and reclaimed soil capability specific to the oil sands region. Additional resources are also available, such as guidelines for the reclamation of terrestrial and wetland habitats that represent the best management practices for reclamation research in revegetation, soil salvage, stockpiling and placement, tailings reclamation, end pit lakes, wetlands and biodiversity. 16 refs., 1 fig.

  19. Preparation of pure phenols from tars

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, J

    1929-06-18

    A process is disclosed for preparing pure phenols from brown coal and shale tar, characterized in that the alkaline extract obtained from the tar is oxidized and concurrently the alkaline solution is separated from the existing impurities by heating with steam at high temperature, which finally reaches at least 150/sup 0/C.

  20. Treatment of oil sands mature fine tailings with silica

    Energy Technology Data Exchange (ETDEWEB)

    Moffett, R.H. [DuPont Canada Inc., Mississauga, ON (Canada)

    2010-07-01

    This PowerPoint presentation discussed a method of treating mature fine tailings (MFT) with silica. Rheology modifications with silica treatments were examined. Experimental studies demonstrated a significant slump at 30 minutes after mixing. Flow properties were studied at a 2 degree angle. The MFT thin lift evaporative drying procedure was used to determine the effects of the silica treatments. Methods of using pressure to dewater MFTs were reviewed. The results of a field test conducted to determine the flow behaviour of MFTs treated with low dose silica were presented. Drying characteristics and strength gains were also evaluated. Results of the study showed that the MFTs had a tendency to channel at discharge points. After a 15 day period that included a freeze-thaw the MFTs had cracks that continued to enlarge, full depth cracking, and fine cracking. The field tests demonstrated that in-situ polymerization of silica within the water phase of fluid fine tails provides significant modifications to rheological properties, and that the onset of rheological modification can be controlled over a range of conditions and times. tabs., figs.

  1. New method for the exact determination of phenols in low-temperature tar and tar oils

    Energy Technology Data Exchange (ETDEWEB)

    Lambris, G; Haferkorn, H

    1949-01-01

    A 3-gram sample of water-free tar or tar oil containing approximately 50% phenols is dissolved in a mixture of benzene and xylene and a known excess of a 20% KOH solution of known normality saturated with benzene and xylene is added. Weight of the KOH is determined by difference. This mixture is shaken repeatedly in a 300-milliliter separatory funnel. After standing for 0.5 h, the dark or almost black phenolate solution containing the major portion is separated and weighed. Care must be taken to prevent the induction of solids. The phenolate in the residue is extracted with hot water and titrated with 0.2N HCl and 1 ml. Congo red (1:100). If water is present in the tar or tar oil, 100 ml of xylene is added immediately after weighing and the water separated by distillation the weight of which must be determined. Any phenols carried over are dissolved in the small quantity of xylene in the distillate. This quantity is added to the bulk of the xylene. After any remaining phenols are extracted from the tar residue with boiling benzene, the benzene-xylene mixture is treated with KOH as above. The accuracy of the method is estimated to be +-1% as shown by experiments with phenol; o-, m-, and p-cresol; cresol mixture; and pyrocatechol. The weight of the dissolved phenols X is determined by X = c - a + cd/(ab - d) where a = weight of KOH, b = HCl used per gram of KOH, C = weight of major portion of phenolate solution, which is formed by shaking the phenol solution with KOH, d = HCl used for titration of phenolate residue.

  2. Mining aspects of hard to access oil sands deposits

    Energy Technology Data Exchange (ETDEWEB)

    Stephenson, G.; Wright, D.; Lukacs, Z. [Norwest Corp., Calgary, AB (Canada)

    2006-07-01

    While a variety of oil sands mining technologies have been explored since the 1960s, the oil sands industry has generally favoured truck and shovel mining as a proven, low-cost mining solution. However, surface mining economics are affected by the price of bitumen, haul distances, tailings storage and geotechnical constraints. Maintenance, labour and the cost of replacing tires and ground engaging tools also have a significant impact on the economics of surface mining. Large volumes of water are used in surface mining, and remediation of surface mined areas can take hundreds of years. Damage to machinery is common as oil sands are abrasive and adhere to equipment. This presentation examined recent technologies developed to improve the economics of surface mining. Various extraction and tailings technologies were reviewed. Issues concerning the integration of mining and extraction processes were discussed. Various monitoring tools were evaluated. A review of new underground mining options included outlines of: longwall mining; sub-level caving; tunnel boring; and room and pillar extraction techniques. A generalized regional geology was presented. It was concluded that the oil sands surfacing mining industry should concentrate on near-term research needs to improve the performance and economics of proven technologies. Screening studies should also be conducted to determine the focus for the development of underground technologies. refs., tabs., figs.

  3. Infrared absorption characteristics of hydroxyl groups in coal tars

    Energy Technology Data Exchange (ETDEWEB)

    Cannon, S A; Chu, C J; Hange, R H; Margrave, J L

    1987-01-01

    Tar evolution was observed over a temperature range of 150-600 C for four coals. Pittsburgh bituminous, Illinois No.6, Rawhide subbituminous, and Texas lignite. Isolation of the evolved tars in a nitrogen matrix at 15 degrees K produced better resolved infrared spectra than those in a coal matrix, thus enhancing structural characterization of the tar molecules. Two distinct hydroxyl functional groups in the tar molecules free of hydrogen bonding were identified for the first time without interference from H/sub 2/O absorptions. These absorptions at 3626.5 cm/sup -1/ have been assigned to phenolic hydroxyls. It is suggested that carboxylic and aliphatic hydroxyl groups do not survive the vaporization process. Tars from Illinois No.6 were found to contain the largest amount of phenolic hydroxyl; Pittsburgh No. 8 tar contains approximately half of that for Illinois No.6 while Rawhide and Texas lignite contain much less phenolic than either of the other coals. 10 references, 6 figures, 1 table.

  4. Applications in the oil sands industry for Particlear{sup R} silica microgel

    Energy Technology Data Exchange (ETDEWEB)

    Moffett, B. [DuPont Chemical Solutions Enterprise, Wilmington, DE (United States)

    2009-07-01

    This presentation demonstrated the use of Particlear{sup R} silica microgel in the oil sands industry. The silica-based coagulant is an amorphous silicon dioxide microgel solution. The surface area of a football field can be obtained using 2.7 grams of the substance. The coagulation mechanism is achieved by charge neutralization and inter-particle bridging. The microgel is manufactured at the point of use from commodity chemicals, water, and carbon dioxide (CO{sub 2}). Applications for the microgel include potable water treatment, paper retention, and animal processing wastewater. In the oil sands industry, Particlear{sup R} can be used in tailings flocculation, thickened tailings drying, steam assisted gravity drainage (SAGD) water treatment, and enhanced bitumen recovery. It was concluded that the microgel can be used in many oil sands processing and liquid-solid separation processes in order to remove dissolved solids and organics and increase the rate of solids dewatering. tabs., figs.

  5. Sunflower oil in the treatment of hot tar burns.

    Science.gov (United States)

    Türegün, M; Oztürk, S; Selmanpakoğlu, N

    1997-08-01

    Hot tar burns compose a unique class of thermal injury, because removal of this highly sticky compound may be very difficult without inflicting additional tissue damage. Early removal of tar facilitates assessment of the burn and improves patient comfort. Although the use of many substances for the painless removal of tar has been described, we used sunflower oil effectively in the treatment of four tar burn patients. This first report describes the practical and successful use of sunflower oil which was easily obtained from the hospital kitchen.

  6. Influence of Amang (Tin Tailing) on Geotechnical Properties of Clay Soil

    International Nuclear Information System (INIS)

    Zulfahmi, A.R.; Zuhairi, W.Y.W.; Raihan, M.T.; Sahibin, A.R.; Razi, I.W.M.; Tukimat, L.; Syakireen, Z.S.N.; Noorulakma, A.

    2012-01-01

    Amang or tin tailing is commonly found in the vicinity of disused mining area and responsible in downgrading the water quality, landscape and mechanical behaviour of soils. It was generated from extraction process of separating valuable metal from particular ore. This paper presents the geotechnical characteristics of amang-contaminated clay soil. The geotechnical properties of uncontaminated soils were studied in order to compare to that of amang contaminated soils. The base soil used in this study represents completely weathered horizon of meta sedimentary rock. Meanwhile, tin tailing sample was taken from the disused mine at Sungai Lembing, Pahang. The geotechnical characterisations of base soil and contaminated soils were determined based on consistency index, compaction behaviour, hydraulic conductivity and undrained shear strength (UU tests). Contaminated soil samples were prepared by adding 5, 10 and 20 % of tailing, based on dry weigh of the studied base soil. The results from the particle size distribution analysis showed that residual soil from meta sedimentary rock comprised 42.6 % clay, 32.2 % silt and 25.2 % sand whilst tailing was dominated by 98 % of sand fraction. XRD analysis indicated the presence of quartz, kaolinite and muscovite minerals in the studied soil. The specific gravity of soil used is 2.67 and the pH is 3.88. Tailing found to have higher specific gravity of 3.37. The consistency index of contaminated soils showed that liquid limit, wL and plastic limit, wP decreased with the increase in the percentage of tailing added to the soil samples. The value of maximum dry density, ρ dry max increased while optimum moisture content decreased due to the increase in tailing content in soil sample. The permeability of contaminated soil also increased with the increase in tailing contents ranged from 19.8 cm/ hr to 23.8 cm/ hr. The undrained shear strength, Cu, of contaminated soil decreased from 646 kPa (5 % of tailing) to 312 kPa (20 % of

  7. Tar dew point analyser as a tool in biomass gasification

    Energy Technology Data Exchange (ETDEWEB)

    Vreugdenhil, B.J.; Kuipers, J. [ECN Biomass, Coal and Environmental Research, Petten (Netherlands)

    2008-08-15

    Application of the Tar Dew point Analyzer (TDA) in different biomass based gasification systems and subsequent gas cleaning setups has been proven feasible. Such systems include BFB gasifiers, CFB gasifier and fixed bed gasifiers, with tar crackers or different scrubbers for tar removal. Tar dew points obtained with the TDA give direct insight in the performance of the gas cleaning section and help prevent any tar related problems due to condensation. The current TDA is capable of measuring tar dew points between -20 to 200C. This manuscript will present results from 4 different gasification setups. The range of measured tar dew points is -7 to 164C with comparable results from the calculated dew points based on the SPA measurements. Further detail will be presented on the differences between TDA and SPA results and explanations will be given for deviations that occurred. Improvements for the TDA regarding future work will be presented.

  8. The catalytic cracking mechanism of lignite pyrolysis char on tar

    International Nuclear Information System (INIS)

    Lei, Z.; Huibin, H.; Xiangling, S.; Zhenhua, M.; Lei, Z.

    2017-01-01

    The influence of different pyrolysis conditions for tar catalytic cracking will be analyzed according to the lignite pyrolysis char as catalyst on pyrolytic tar in this paper. The pyrolysis char what is the by-product of the cracking of coal has an abundant of pore structure and it has good catalytic activity. On this basis, making the modified catalyst when the pyrolysis char is activation and loads Fe by impregnation method. The cracking mechanism of lignite pyrolytic tar is explored by applying gas chromatograph to analyze splitting products of tar. The experimental results showed that: (1) The effect of tar cracking as the pyrolysis temperature, the heating rate, the volatilization of pyrolysis char and particle size increasing is better and better. The effect of the catalytic and cracking of lignite pyrolysis char in tar is best when the heating rate, the pyrolysis temperature, the volatiles of pyrolysis char, particle size is in specific conditions.(2) The activation of pyrolysis char can improve the catalytic effect of pyrolysis char on the tar cracking. But it reduces the effect of the tar cracking when the pyrolysis char is activation loading Fe. (author)

  9. Low-temperature tar and oil: properties and applications

    Energy Technology Data Exchange (ETDEWEB)

    Heinze, R

    1942-01-01

    In Germany the value of low-temperature tar is largely dependent on its fuel fractions; these vary with the coal and the method of carbonization (external heating or recirculated gases). Brown-coal tars can be processed by distillation, cracking under pressure, hydrogenation under pressure (largest volume of tar is processed by this method) and by solvent extraction, with EtOH, SO/sub 2/, or phenol. Each of these processes is discussed in detail. In the pressure-hydrogenation process, 1.25 kilogram of brown-coal tar yields approximately 1 kilogram of gasoline with an octane number of 60 to 70. Low-temperature tars from bituminous coals can be hydrogenated readily but are not well adapted to solvent extraction. Attempts should be made to produce tar approximating the desired characteristics for fuel directly from the carbonizing apparatus. For laboratory carbonization tests, an approximation to results secured by externally heated retorts is secured by using an insert consisting of a series of perforated trays in the 200-gram Fischer aluminum retort; this reduces the capacity to 100 gram. Fractional condensation is used to separate heavy oil, middle oil, and liquor; low-boiling products are condensed at -20/sup 0/ by solid CO/sub 2/.

  10. Chemical-composition studies of low-temperature-carbonization coal tar

    Energy Technology Data Exchange (ETDEWEB)

    Edel' shtein, N G; Lanin, V A

    1955-01-01

    Pintsch-oven low-temperature tar was separated into its constituents by conventional methods, and the average of 2 results was neutral asphaltenes 12.56, basic asphaltenes 2.61, acid asphaltenes 18.82, phenols 13.23, bases 2.31, neutral oil 17.66, crystalline paraffins 7.34, silica-gel tars (I) (benzene extract) 15.40, I (acetone extract) 2.47, carbenes 0.45, and carbides and dust 1.44%. The low-temperature-tar asphaltenes and tars differ from shale-oil tars by being lower in C and higher in H, with a considerably higher C:H ratio. Their specific gravity is somewhat higher, and they are cyclic in structure. The asphaltenes and silica-gel tars of coal tar and shale oil were hydrogenated, molecular weights d/sub 4//sup 20/ and n/sub 4//sup 20/ of the separated compounds were determined, and empirical formulas of the hydrogenated compounds calculated. The neutral oil was separated into saturated, intermediate (iodine number 23), unsaturated (iodine number 51), a small quantity of a mixture of unsaturated and aromatic hydrocarbons, and 44.9% aromatic hydrocarbons. While naphthenes seem to be predominantly present in the neutral-oil fraction of shale oil, aromatic hydrocarbons are predominant in coal oil.

  11. Process of transforming tars, etc

    Energy Technology Data Exchange (ETDEWEB)

    1929-04-11

    A process is described for treating tars obtained by carbonization, at high or low temperature, of coals, lignites, shales, and other carbonaceous materials or fractions of these tars, for obtaining products of greater value, consisting of polymerizing or saturating the unstable hydrocarbons in the presence of catalyzers by the progressing action particularly of halogenated metals, such as titanium tetrachloride, iron chloride, etc. and applying a known process of recovery, the disclosed process leading to an important reduction of final losses.

  12. Mineral oils, tars. [British patent

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, A M; Handmarch, E

    1933-08-11

    Hydrocarbon materials such as mineral oils and tars from coal, shale, lignite, or peat are freed from phenols and like oxy-bodies by heating under pressure in a closed vessel to a temperature and for a time sufficient to effect reduction of the oxy-bodies, and then removing the water formed by the reaction. 350/sup 0/ to 400/sup 0/C. for 30 to 60 minutes is suitable. Any wax-like constituents are converted to liquids of lower viscosity and settling point. The product may be fractionated to give light oils and a residue of aviation Diesel fuel. In an example, oil from the low-temperature distillation of coal and having a tar acid content of 30 per cent is treated in a tubular converter at 380/sup 0/C. and 400 lb. per sq. in for 40 min., and the benzine toluol, and xylol distilled; the residue has a tar acid content of only 7.6 per cent.

  13. Oil sands naphthenic acids: a review of properties, measurement, and treatment.

    Science.gov (United States)

    Brown, Lisa D; Ulrich, Ania C

    2015-05-01

    The Alberta oil sands contain one of the world's largest reserves of oil - over 169 billion barrels of bitumen are economically recoverable with current extraction technologies. Surface mining and subsequent hot water extraction of bitumen from the ore generates about nine cubic meters of raw tailings per cubic meter of oil. Oil sands facilities are required to operate under a policy of zero water discharge, resulting in ponds containing more than one billion cubic meters of tailings, a mixture of sand, fines and process-affected water. Process-affected water contains numerous organic compounds, including naphthenic acids (NAs), which have been identified as the primary source of acute toxicity of process-affected water. Developments in analytical techniques, aerobic biodegradability, and treatment via chemical oxidation (ozone) of NAs are reviewed. The field continues to be challenged by the lack of a cost-effective, accurate analytical technique for NAs or an understanding of all the organic constituents in process-affected water that may be contributing to observed toxicity and thus requiring treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Reaction Mechanism of Tar Evolution in Biomass Steam Gasification for Hydrogen Production

    International Nuclear Information System (INIS)

    Shingo Katayama; Masahiro Suzuki; Atsushi Tsutsumi

    2006-01-01

    Reaction mechanism of tar evolution in steam gasification of biomass was investigated with a continuous cross-flow moving bed type differential reactor, in which tar and gases can be fractionated according to reaction time. We estimated that time profile of tar and gas evolution in the gasification of cellulose, xylan, and lignin, and compared it with experimental product time profile of real biomass gasification. The experimental tar evolution rate is different from estimated tar evolution rate. The estimated tar evolution rate has a peak at 20 s. On the other hand, the experimental tar evolution rate at 20 s is little, and tar at initial stage includes more water-soluble and water-insoluble compounds. It can be concluded that in the real biomass steam gasification the evolution of tar from cellulose and lignin component was found to be precipitated by that from hemi-cellulose component. (authors)

  15. Perch population assessment in lakes reclaimed using oil-sands derived material

    International Nuclear Information System (INIS)

    Heuvel, M.R. van den; Dixon, D.G.; Power, M.; Boerger, H.; MacKinnon, M.D.; Meer, T. van

    1995-01-01

    The mining and extraction of petroleum products from oil-sands involves large areas of land and produces enormous volumes of tailings. One possible land reclamation option is to incorporate fine-tailings material into the bottoms of constructed lakes capped with natural surface water. The wet landscape method represents potential risk to aquatic biota-naphthenic acids and PAHs elute from pore water contained in the fine-tailings substrate. In spring 1995 yellow perch were stocked into a large-scale (5ha) experimental pond that consisted of fine-tailings capped with natural water as well as into two other reclaimed ponds that were constructed with oil-sands overburden material. Prior to stocking of perch, ponds had colonized with cyprinids, macrophytes and benthic invertebrates over a two year period. Perch were sampled in fall 1995 for age, condition factor, liver size, gonad size, fecundity, stomach contents, liver mixed-function oxygenase activity (MFO), bile PAH metabolites and plasma steroid hormones. When compared to the source lake, perch in the DP did not show reduced reproductive potential. Perch in all of the reclaimed ponds demonstrated exposure to organic compounds as indicated by marginally induced MFO activity and increased liver size. Exposure to naphthenates and PAHs in water as well as ecological environmental factors will be discussed

  16. DECOMPOSITION OF TARS IN MICROWAVE PLASMA – PRELIMINARY RESULTS

    Directory of Open Access Journals (Sweden)

    Mateusz Wnukowski

    2014-07-01

    Full Text Available The paper refers to the main problem connected with biomass gasification - a presence of tar in a product gas. This paper presents preliminary results of tar decomposition in a microwave plasma reactor. It gives a basic insight into the construction and work of the plasma reactor. During the experiment, researches were carried out on toluene as a tar surrogate. As a carrier gas for toluene and as a plasma agent, nitrogen was used. Flow rates of the gases and the microwave generator’s power were constant during the whole experiment. Results of the experiment showed that the decomposition process of toluene was effective because the decomposition efficiency attained above 95%. The main products of tar decomposition were light hydrocarbons and soot. The article also gives plans for further research in a matter of tar removal from the product gas.

  17. Recovery of very viscous lubricating oils from shale-tar, etc

    Energy Technology Data Exchange (ETDEWEB)

    Erdmann, E

    1918-01-22

    A process is disclosed for the recovery of very viscous lubricating oils from brown-coal tar and shale tar, consisting in driving off from the crude tar or the tar freed from volatile constituents after removal of paraffin by precipitation with a volatile solvent such as acetone or one of its homologs, the light oils more or less completely with superheated steam from about 200 to 250/sup 0/C without any outside heating over a free flame.

  18. Field performance of de-watered fluid fine tailings for oil sands reclamation

    Energy Technology Data Exchange (ETDEWEB)

    Ward Wilson, G.; Kabwe, Louis [University of Alberta (Canada); Donahue, Robert [Applied Geochemical Engineering Inc. (Canada); Lahaie, Rick [Syncrude Canada Ltd (Canada)

    2011-07-01

    This document presents research carried out by Syncrude Canada Ltd and its partners to evaluate several methods of de-watering fluid fine tailings to increase the solids content and at the same time produce a tailings profile which will permit final reclamation. Several de-watering methods are discussed in this paper, particularly in-line flocculation and centrifuged fluid fine tailings. First, in-line flocculation with organic polymers is discussed followed by thin left deposition, then the flocculation and centrifugation process to produce a paste- like material that is deposited in a thicker layer is presented. This document details the preliminary performance of both discussed methods; extensive instrumentation was used to measure de-watering rates due to consolidation, atmospheric drying, downward drainage to the foundation materials, and freeze/thaw consolidation. Finally, a summary of the measured results of de-watering rates and numerical model results obtained from the SoilCover model are presented and discussed.

  19. VAPOR PRESSURES AND HEATS OF VAPORIZATION OF PRIMARY COAL TARS

    Energy Technology Data Exchange (ETDEWEB)

    Eric M. Suuberg; Vahur Oja

    1997-07-01

    This project had as its main focus the determination of vapor pressures of coal pyrolysis tars. It involved performing measurements of these vapor pressures and from them, developing vapor pressure correlations suitable for use in advanced pyrolysis models (those models which explicitly account for mass transport limitations). This report is divided into five main chapters. Each chapter is a relatively stand-alone section. Chapter A reviews the general nature of coal tars and gives a summary of existing vapor pressure correlations for coal tars and model compounds. Chapter B summarizes the main experimental approaches for coal tar preparation and characterization which have been used throughout the project. Chapter C is concerned with the selection of the model compounds for coal pyrolysis tars and reviews the data available to us on the vapor pressures of high boiling point aromatic compounds. This chapter also deals with the question of identifying factors that govern the vapor pressures of coal tar model materials and their mixtures. Chapter D covers the vapor pressures and heats of vaporization of primary cellulose tars. Chapter E discusses the results of the main focus of this study. In summary, this work provides improved understanding of the volatility of coal and cellulose pyrolysis tars. It has resulted in new experimentally verified vapor pressure correlations for use in pyrolysis models. Further research on this topic should aim at developing general vapor pressure correlations for all coal tars, based on their molecular weight together with certain specific chemical characteristics i.e. hydroxyl group content.

  20. Microstructure and properties of lignite tar and pitch. Part II

    Energy Technology Data Exchange (ETDEWEB)

    Walther, H

    1954-01-01

    Photomicrographs reveal the presence of crystalline wax which affects the working properties in lignite tars and pitch. The crystals are large needles after slow cooling and small after rapid cooling. The crystals are paraffinic in character. All samples were nonhomogeneous. Thus the properties of lignite tar and pitch are varied by the source of the lignite and history of the specimen, neither softening point nor dropping point seems to satisfactorily characterize these tars. The samples exhibit thixotropic behavior characteristic of a structural viscosity and show hysteresis loops on varying the working rate. The variations have hindered use of lignite tars and pitches except where solubility in a solvent such as coal tar oil can be used to advantage.

  1. Catalytic destruction of tar in biomass derived producer gas

    International Nuclear Information System (INIS)

    Zhang Ruiqin; Brown, Robert C.; Suby, Andrew; Cummer, Keith

    2004-01-01

    The purpose of this study is to investigate catalytic destruction of tar formed during gasification of biomass, with the goal of improving the quality of the producer gas. This work focuses on nickel based catalysts treated with alkali in an effort to promote steam gasification of the coke that deposits on catalyst surfaces. A tar conversion system consisting of a guard bed and catalytic reactor was designed to treat the producer gas from an air blown, fluidized bed biomass gasifier. The guard bed used dolomite to crack the heavy tars. The catalytic reactor was used to evaluate three commercial steam reforming catalysts. These were the ICI46-1 catalyst from Imperial Chemical Industry and Z409 and RZ409 catalysts from Qilu Petrochemical Corp. in China. A 0.5-3 l/min slipstream from a 5 tpd biomass gasifier was used to test the tar conversion system. Gas and tar were sampled before and after the tar conversion system to evaluate the effectiveness of the system. Changes in gas composition as functions of catalytic bed temperature, space velocity and steam/TOC (total organic carbon) ratio are presented. Structural changes in the catalysts during the tests are also described

  2. Characterization of acid tars

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, Sunday A., E-mail: sunday.leonard@ucl.ac.uk [Department of Civil Environmental and Geomatic Engineering, University College London, Chadwick Building, Gower Street, London, WC1E 6BT (United Kingdom); Stegemann, Julia A. [Department of Civil Environmental and Geomatic Engineering, University College London, Chadwick Building, Gower Street, London, WC1E 6BT (United Kingdom); Roy, Amitava [J. Bennett Johnston, Sr., Centre for Advance Microstructures and Devices (CAMD), 6980 Jefferson Highway, Louisiana State University, Baton Rouge, LA, 70806 (United States)

    2010-03-15

    Acid tars from the processing of petroleum and petrochemicals using sulfuric acid were characterized by gas chromatography/mass spectrometry (GC/MS), inductively coupled plasma/optical emission spectrometry (ICP/OES), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectrometry, and scanning electron microscopy/energy dispersive X-ray (SEM/EDX) micro-analysis. Leaching of contaminants from the acid tars in 48 h batch tests with distilled water at a liquid-to-solid ratio 10:1 was also studied. GC/MS results show that the samples contained aliphatic hydrocarbons, cyclic hydrocarbons, up to 12 of the 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs), and numerous other organic groups, including organic acids (sulfonic acids, carboxylic acids and aromatic acids), phenyl, nitrile, amide, furans, thiophenes, pyrroles, and phthalates, many of which are toxic. Metals analysis shows that Pb was present in significant concentration. DSC results show different transition peaks in the studied samples, demonstrating their complexity and variability. FTIR analysis further confirmed the presence of the organic groups detected by GC/MS. The SEM/EDX micro-analysis results provided insight on the surface characteristics of the samples and show that contaminants distribution was heterogeneous. The results provide useful data on the composition, complexity, and variability of acid tars; information which hitherto have been scarce in public domain.

  3. Characterization of acid tars

    International Nuclear Information System (INIS)

    Leonard, Sunday A.; Stegemann, Julia A.; Roy, Amitava

    2010-01-01

    Acid tars from the processing of petroleum and petrochemicals using sulfuric acid were characterized by gas chromatography/mass spectrometry (GC/MS), inductively coupled plasma/optical emission spectrometry (ICP/OES), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectrometry, and scanning electron microscopy/energy dispersive X-ray (SEM/EDX) micro-analysis. Leaching of contaminants from the acid tars in 48 h batch tests with distilled water at a liquid-to-solid ratio 10:1 was also studied. GC/MS results show that the samples contained aliphatic hydrocarbons, cyclic hydrocarbons, up to 12 of the 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs), and numerous other organic groups, including organic acids (sulfonic acids, carboxylic acids and aromatic acids), phenyl, nitrile, amide, furans, thiophenes, pyrroles, and phthalates, many of which are toxic. Metals analysis shows that Pb was present in significant concentration. DSC results show different transition peaks in the studied samples, demonstrating their complexity and variability. FTIR analysis further confirmed the presence of the organic groups detected by GC/MS. The SEM/EDX micro-analysis results provided insight on the surface characteristics of the samples and show that contaminants distribution was heterogeneous. The results provide useful data on the composition, complexity, and variability of acid tars; information which hitherto have been scarce in public domain.

  4. Ultrasound assisted, thermally activated persulfate oxidation of coal tar DNAPLs.

    Science.gov (United States)

    Peng, Libin; Wang, Li; Hu, Xingting; Wu, Peihui; Wang, Xueqing; Huang, Chumei; Wang, Xiangyang; Deng, Dayi

    2016-11-15

    The feasibility of ultrasound assisted, thermally activated persulfate for effective oxidation of twenty 2-6 ringed coal tar PAHs in a biphasic tar/water system and a triphasic tar/soil/water system were investigated and established. The results indicate that ultrasonic assistance, persulfate and elevated reaction temperature are all required to achieve effective oxidation of coal tar PAHs, while the heating needed can be provided by ultrasonic induced heating as well. Further kinetic analysis reveals that the oxidation of individual PAH in the biphasic tar/water system follows the first-order kinetics, and individual PAH oxidation rate is primary determined by the mass transfer coefficients, tar/water interfacial areas, the aqueous solubility of individual PAH and its concentration in coal tar. Based on the kinetic analysis and experimental results, the contributions of ultrasound, persulfate and elevated reaction temperature to PAHs oxidation were characterized, and the effects of ultrasonic intensity and oxidant dosage on PAHs oxidation efficiency were investigated. In addition, the results indicate that individual PAH degradability is closely related to its reactivity as well, and the high reactivity of 4-6 ringed PAHs substantially improves their degradability. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. The future of water quality and the regulatory environment for the oil sands and coalbed methane development

    International Nuclear Information System (INIS)

    Kasperski, K.; Mikula, R.

    2004-01-01

    The use of consolidated tailings in recent years for the surface mined oil sands bitumen extraction process has resulted in major improvements in water consumption because materials are transported more efficiently in a slurry form. Water storage requirements will be reduced as the cost of handling tailings in the conventional manner becomes clearer. Future improvements may be in the form of mine face sand rejection, more advanced tailings treatment, or the use of clays for continuous reclamation. Sand filtering or stacking technologies can improve tailings properties and reduce the amount of water needed per unit of bitumen. It was noted that although the technologies will minimize land disturbance and fresh water consumption, water chemistries will be driven to the point where extraction recovery is impaired and water treatment will be required. The volumes and quality of water that is pumped out to produce coalbed methane (CBM) was also discussed with reference to the origin of water in coal beds, water resource depletion, water disposal, direct land applications, and surface evaporation. The Alberta Energy and Utilities Board and Alberta Environment are responsible for regulating CBM water issues in the province, including water disposal from CBM production. 41 refs., 6 tabs., 8 figs

  6. Application of organic geochemistry to coastal tar residues from central California

    Energy Technology Data Exchange (ETDEWEB)

    Kvenvolden, K.A.; Rosenbauer, R.J.; Hostettler, F.D.; Lorenson, T.D.

    2000-01-01

    Tar residues are common on the Monterey Bay National Marine Sanctuary. These coastal tar residues have been washed ashore and usually occur on headlands near the high-tide line. In this study, 18 coastal tar residues were collected and analyzed to determine their carbon isotopic compositions and values of selected biomarker ratios. All of the residues have very heavy ({sup 13}C-enriched) carbon isotopic compositions spanning a narrow range ({delta}{sup 13}C = {minus}22.2 to {minus}23.4{per{underscore}thousand}), and 28,30-bisnorhopane is present in all samples. These same geochemical characteristics are found in Monterey Formation oils from which the coastal tar residues were likely derived. These coastal residues could result from natural seeps or from accidental spills. Statistically the coastal tar residues can be organized into three groups, each of which may represent different spill or seep events. Seven samples of potential local representative sources for the tar residues were examined, but none could account for the coastal tars.

  7. Dose assessment of remedial action for uranium tailing impoundment of a nuclear factory

    International Nuclear Information System (INIS)

    Li Xutong; Ma Ruwei; Guo Zede

    2000-01-01

    A large uranium tailing impoundment in China will be closure and remedial action have been planned. The remedial action will include shaping and covering the dam and beach in order to prevent the impoundment from damage and restrict spread of tailing sands and emission of radon. The author presents the analysis and estimation of the exposure to workers for remedial action and to public after the remedial action. To estimate the exposure to workers, the pathway of inhalation of radon, tailing sands in suspension and external γ exposure were taken into consideration. The exposure scenario is considered as probably maximum exposure to the workers who work on the tailing pile without any protection measures, the dose is 6.0 mSv/a. Two situation for the exposure to public after remedial action were considered: normal and abnormal condition. For the normal condition, inhalation of radon emitted from impoundment is only the pathway to public for the exposure, and individual dose for critical group of public is 0.053 mSv/a, collective dose for population within 80 km is 1.0 man·Sv/a. For the abnormal conditions, four scenarios were considered, i.e. dwelling on tailing pile, farming on tailing pile, living in a house built by contaminated materials and some temporal activities on the pile. The scenarios of dwellings is living in a house on the pile and drinking contaminated water. The maximum individual dose is 27 mSv/a

  8. Distribution of clay minerals in the process streams produced by the extraction of bitumen from Athabasca oil sands

    Energy Technology Data Exchange (ETDEWEB)

    Kaminsky, H.A.W.; Etsell, T.H.; Ivey, D.G. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering; Omotoso, O. [Natural Resources Canada, Devon, AB (Canada). CETC

    2009-02-15

    The clay minerals present in the oil sands were studied with particular reference to how they are partitioned in bitumen ore during the extraction process. Bitumen production from surface-mined oil sands accounts for nearly two-thirds of the total bitumen production in Alberta. Every cubic meter of mined ore results in 1.3 cubic meters of mature fine tailings (MFT). The characteristic differences between the clay minerals that report to the froth versus the tailings streams were also examined to determine which minerals could impact different unit operations in the bitumen extraction process. X-ray diffraction and random powder samples were used to quantify the clay minerals. Particle size distribution and clay activity balances were also conducted. The degree of partitioning during the conditioning and flotation stages in a batch extractor was determined by the surface properties of the clay minerals. The water-continuous tailings stream was separated into fine and coarse tailings fractions through sedimentation. The study showed that bitumen-clay interactions may be dominated by kaolinite or iron oxides. Clays are responsible for the poor settling behaviour of MFTs. The clay minerals present in the oil sands include illite, illite-smectite, kaolinite, kaolinite-smectite, and chlorite. The close proximity of the tailings ponds to the Athabasca River and volatile organic compounds (VOCs) emission require that the ponds be reclaimed to a natural landscape before mine closure. In addition to its impact on fine tailings reclamation, clay mineralogy plays a role in extraction froth flotation and emulsion stability during froth treatment. The mineralogy of the froth solids was found to be different from the mineralogy of the middlings and tailings solids. 39 refs., 6 tabs., 6 figs.

  9. Final Safety Assessment of Coal Tar as Used in Cosmetics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    Coal Tar is a semisolid by-product obtained in the destructive distillation of bituminous coal, which functions in cosmetic products as a cosmetic biocide and denaturant-antidandruff agent is also listed as a function, but this is considered an over-the-counter (OTC) drug use. In 2002, Coal Tar was reported to the Food and Drug Administration (FDA) to be used in four formulations, all of which appear to be OTC drug products. Coal Tar is monographed by the FDA as Category I (safe and effective) OTC drug ingredient for use in the treatment of dandruff, seborrhoea, and psoriasis. Coal Tar is absorbed through the skin of animals and humans and is systemically distributed. Although the Cosmetic Ingredient Review (CIR) Expert Panel believes that Coal Tar use as an antidandruff ingredient in OTC drug preparations is adequately addressed by the FDA regulations, the Panel also believes that the appropriate concentration of use of Coal Tar in cosmetic formulations should be that level that does not have a biological effect in the user. Additional data needed to make a safety assessment include product types in which Coal Tar is used (other than as an OTC drug ingredient), use concentrations, and the maximum concentration that does not induce a biological effect in users.

  10. UTILIZATION OF AQUEOUS-TAR CONDENSATES FORMED DURING GASIFICATION

    Directory of Open Access Journals (Sweden)

    Anna Kwiecińska

    2016-11-01

    Full Text Available Gasification of solid fuels is an alternative process for energy production using conventional and renewable fuels. Apart from desired compounds, i.e. carbon oxide, hydrogen and methane, the produced gas contains complex organic (tars and inorganic (carbonizate, ammonia contaminants. Those substances, together with water vapor, condensate during cooling of the process gas, what results in the formation of aqueous-tar condensate, which requires proper methods of utilization. The management of this stream is crucial for commercialization and application of the gasification technology. In the paper the treatment of aqueous-tar condensates formed during biomass gasification process is discussed. The removal of tars from the stream was based on their spontaneous separation. The aqueous stream was subjected to ultrafiltration operated at different pressures. Such a treatment configuration enabled to obtain highly concentrated retentate, which could be recycled to the gasifier, and filtrate, which could be subjected to further treatment.

  11. Evaluation of lignite tar

    Energy Technology Data Exchange (ETDEWEB)

    Gossedin, A

    1946-01-01

    Tar from the low-temperature (450/sup 0/) carbonization of lignite from Bouches-du-Rhone was hydrogenated in the presence of a catalyst based on MoS/sub 2/ with a 3:1 H:N mixture. Processing (at 470/sup 0/ and 400 atmospheres) for maximum production of gasoline yielded 86 wt % of a product of boiling 55 to 186/sup 0/ and motor octane number 75. An alternative is to hydrogenate with a view to producing solvents and lubricants. For this purpose the tar was separated by distillation (at 20 millimeters, cutting at 220/sup 0/) into two fractions of equal volume. On hydrogenation (at 300/sup 0/ and 400 atmospheres) the light part yields a gasoline H/sub 2/O-soluble cut, a highly aromatic solvent fraction, a heavier cut (280/sup 0/ to 320/sup 0/) suitable as a plasticizer, and a phenol fraction. The heavier part of the tar is hydrogenated (at 380/sup 0/ and 400 atmospheres) to give spindle oil and lubricating oil of medium eta (11.2 centistokes at 98.2/sup 0/), moderate eta index (64), good pour point (-7/sup 0/), and good oxidizing characteristics. The overall yield of products from the two portions is 86.9% (gasoline and solvent 32, light phenols 9.7, spindle oil 14.2, medium lubricating oil 25.7, wax, 5.3%).

  12. Modeling Tar Recirculation in Biomass Fluidized Bed Gasification

    NARCIS (Netherlands)

    Heineken, Wolfram; De la Cuesta de Cal, Daniel; Zobel, Nico

    2016-01-01

    A biomass gasification model is proposed and applied to investigate the benefits of tar recirculation within a gasification plant. In the model, tar is represented by the four species phenol, toluene, naphthalene, and benzene. The model is spatially one-dimensional, assuming plug flow for the

  13. A hybrid froth flotation-filtration system as a pretreatment for oil sands tailings pond recycle water management: Bench- and pilot-scale studies.

    Science.gov (United States)

    Loganathan, Kavithaa; Bromley, David; Chelme-Ayala, Pamela; Gamal El-Din, Mohamed

    2015-09-15

    Through sustainable water management, oil sands companies are working to reduce their reliance on fresh water by minimizing the amount of water required for their operations and by recycling water from tailings ponds. This study was the first pilot-scale testing of a hybrid technology consisting of froth flotation combined with filtration through precoated submerged stainless steel membranes used to treat recycle water from an oil sands facility. The results indicated that the most important factor affecting the performance of the hybrid system was the influent water quality. Any rise in the levels of suspended solids or total organic carbon of the feed water resulted in changes of chemical consumption rates, flux rates, and operating cycle durations. The selections of chemical type and dosing rates were critical in achieving optimal performance. In particular, the froth application rate heavily affected the overall recovery of the hybrid system as well as the performance of the flotation process. Optimum surfactant usage to generate froth (per liter of treated water) was 0.25 mL/L at approximately 2000 NTU of influent turbidity and 0.015 mL/L at approximately 200 NTU of influent turbidity. At the tested conditions, the optimal coagulant dose was 80 mg/L (as Al) at approximately 2000 NTU of influent turbidity and recycle water. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Metal removal from tailings ponds water using indigenous micro-algae

    Energy Technology Data Exchange (ETDEWEB)

    Mahdavi, H.; Ulrich, A.; Liu, Y. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering

    2010-07-01

    Each barrel of oil produced by oil sands produce 1.25 m{sup 3} of tailings. The tailings are collected in ponds located at mining sites. The tailing pond water (TPW) must be reclaimed and released into the environment. This PowerPoint presentation discussed a method of removing metals from tailings pond water that used indigenous micro-algae. The in situ experimental method used Parachlorella kessliri to treat 2 ponds. The TPW was enriched with low and high concentrations of nutrients. Dry cell biomass analyses were then conducted, and the pH of the resulting samples was compared. Inductively coupled plasma mass spectrometry analysis methods were used to determine the initial metal concentrations in the raw TPWs. The study showed that the micro-algae remove significantly more metals when high levels of nutrients are used. tabs., figs.

  15. TSC mobile mining and extraction technology

    Energy Technology Data Exchange (ETDEWEB)

    Lavender, W.J. [TSC Company Ltd., Calgary, AB (Canada)

    2001-11-01

    This Power-Point presentation described an innovative mining and extraction technology developed by Calgary-based TSC Company Ltd. that has provided a major breakthrough in bitumen production from mineable oil sands. The presentation described the process and key mechanical components as demonstrated on oil sands leases. It also described the step change in cost structure and profitability. Oil sands mining provide a hugh resource base with no exploration costs and no decline in production. Despite these advantages, oil sands mining faces the challenge of high capital and operating costs and materials handling. Other challenges include the variability of the ore and environmental impacts. This paper described the fundamentals of the new technology called the Tar Sand Combine (TSC), a continuous mining machine, crusher, cyclone, tailings filter and stacker all in one mobile module. Several viewgraphs were included with the presentation to depict the recovery process as successfully demonstrated at a pilot project. Patent is pending on the process and components. The advantages of the TSC are reduced materials handling, and no tailings ponds are generated since tailings remain where they are mined. The final product is clean bitumen. The specifications of a commercial TSC are: 2000 ton/stream hour mining produce 25,000 bpsd bitumen at 12 per cent ore grade; mined ore bitumen recovery is greater than 95 per cent and the availability factor is 85 per cent. It was concluded that the TSC can maximize oil sands reserves, while providing significant cost savings and environmental benefits. 2 tabs., 24 figs.

  16. Oil sands mine planning and waste management using goal programming

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Awuah, E.; Askari-Nasab, H. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering; Alberta Univ., Edmonton, AB (Canada). Mining Optimization Laboratory

    2010-07-01

    A goal programming method was used to plan waste management processes at an oil sands mine. This method requires the decision maker (DM) to set goals. Mine planning is used to determine a block extraction schedule that maximizes net present value (NPV). Due to land restrictions, tailings facilities are sited within the pit area and dykes are used to contain the tailings. Many of the materials used to construct the dykes come from the mining operation. The mine plan scheduled both ore and dyke material concurrently. Dykes were constructed simultaneously as the mine phase advanced. A model was used to classify an oil sands block model into different material types. A mixed integer goal programming (MIGP) method was used to generate a strategic schedule. Block clustering techniques were used to large-scale mine planning projects. The method was used to verify and validate synthetic and real case data related to the cost of mining all material as waste, and the extra cost of mining dyke material. A case study of an oil sands project was used to demonstrate the method. The study showed that the developed model generates a smooth and uniform strategic schedule for large-scale mine planning projects. tabs., figs.

  17. Oil sands mine planning and waste management using goal programming

    International Nuclear Information System (INIS)

    Ben-Awuah, E.; Askari-Nasab, H.; Alberta Univ., Edmonton, AB

    2010-01-01

    A goal programming method was used to plan waste management processes at an oil sands mine. This method requires the decision maker (DM) to set goals. Mine planning is used to determine a block extraction schedule that maximizes net present value (NPV). Due to land restrictions, tailings facilities are sited within the pit area and dykes are used to contain the tailings. Many of the materials used to construct the dykes come from the mining operation. The mine plan scheduled both ore and dyke material concurrently. Dykes were constructed simultaneously as the mine phase advanced. A model was used to classify an oil sands block model into different material types. A mixed integer goal programming (MIGP) method was used to generate a strategic schedule. Block clustering techniques were used to large-scale mine planning projects. The method was used to verify and validate synthetic and real case data related to the cost of mining all material as waste, and the extra cost of mining dyke material. A case study of an oil sands project was used to demonstrate the method. The study showed that the developed model generates a smooth and uniform strategic schedule for large-scale mine planning projects. tabs., figs.

  18. Composition of coal tar from pyrolysis and hydropyrolysis of Shenmu coal macerals

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Q.; Li, W.; Chen, H.; Li, B. [Shandong Academy of Sciences, Jinan (China)

    2005-08-15

    To understand the relationship of the tar compositions and the coal macerals, the tars obtained from the pyrolysis and hydropyrolysis of Shenmu coal macerals in a fixed-bed reactor were analysed using GC-MS. And the effects of petrographic component, atmosphere and pressure on the yield of aromatic hydrocarbon, phenols, hydrocarbons, oxygen-containing heterocycle and PAHs were systematically investigated. The results show that there is great difference in the composition and the relative content of long chain hydrocarbons, aromatic hydrocarbons, phenols, oxygen-containing heterocycle and PAHs in tars from vitrinite and inertinite pyrolysis. Vitrinite tar contains high content of hydrocarbon with long chain, and inertinite tar contains high content of aromatic hydrocarbons, phenols, oxygen-containing heterocycle and PAHs. It suggests that vitrinite has lower aromaticity and longer chain in its structure than inertinite, which is in well agreement with the result from {sup 13}C NMR and FT-IR test. The tar yield of hydropyrolysis is higher than that of pyrolysis. With increasing the hydrogen pressure, the yield of tar increases greatly. The content of phenols and naphthalene in vitrinite tar form hydropyrolysis under 0.1 MPa is much lower than that form pyrolysis, while that of inertinite tar changes a little. The difference of tar compositions and relative content during pyrolysis and hydropyrolysis reflects the effect of hydrogenation and hydrocracking reactions and the structure characteristics of the macerals. 12 refs., 3 figs.

  19. 48 CFR Appendix to Part 1252 - Tar Matrix

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Tar Matrix Appendix to Part 1252 Federal Acquisition Regulations System DEPARTMENT OF TRANSPORTATION CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Pt. 1252, App. Appendix to Part 1252—Tar Matrix ER27DE05.000...

  20. Low-temperature tar from bituminous coal and its further treatment

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, C J

    1950-01-01

    High-temperature carbonization of bituminous coal yields only 3 to 4 percent tar, as compared with 8 to 10 percent or even more for low-temperature carbonization. The yield of phenols is 20 to 30 times as great from the low-temperature tar. Five conditions that must be met by a satisfactory low-temperature carbonization process are listed. The only method that satisfies all of these conditions is the Brennstoff-Technik (BT) process, in which iron retorts with movable walls are used. One disadvantage of most of the other processes is the high-pitch content of the tar. These tars are processed further to a neutral oil and a phenol-containing oil which are good diesel fuels with high-cetane numbers; the neutral oil can be fractionated to give oils of high-, medium-, and low-cetane number. Attempts to fractionate the tar oil by solvents have not proved commercially useful. However, the tar can be diluted with low-temperature light oil and phenols extracted with NaOH solution without distillation. Some difficulty is found, owing to the simultaneous extraction of viscous resins and other products that are readily removed from the phenols by distillation.

  1. Evaluation of Gravimetric Tar Determination in Particle Samples

    DEFF Research Database (Denmark)

    Hindsgaul, Claus; Henriksen, Ulrik B.; Bentzen, Jens Dall

    2000-01-01

    A comparison of tar determination of particles from a down-draft gasifier using soxhlet extractions (with anisole, dichloromethane and acetone) and pyrolysis of the particles.......A comparison of tar determination of particles from a down-draft gasifier using soxhlet extractions (with anisole, dichloromethane and acetone) and pyrolysis of the particles....

  2. Research investigations in oil shale, tar sand, coal research, advanced exploratory process technology, and advanced fuels research: Volume 1 -- Base program. Final report, October 1986--September 1993

    Energy Technology Data Exchange (ETDEWEB)

    Smith, V.E.

    1994-05-01

    Numerous studies have been conducted in five principal areas: oil shale, tar sand, underground coal gasification, advanced process technology, and advanced fuels research. In subsequent years, underground coal gasification was broadened to be coal research, under which several research activities were conducted that related to coal processing. The most significant change occurred in 1989 when the agreement was redefined as a Base Program and a Jointly Sponsored Research Program (JSRP). Investigations were conducted under the Base Program to determine the physical and chemical properties of materials suitable for conversion to liquid and gaseous fuels, to test and evaluate processes and innovative concepts for such conversions, to monitor and determine environmental impacts related to development of commercial-sized operations, and to evaluate methods for mitigation of potential environmental impacts. This report is divided into two volumes: Volume 1 consists of 28 summaries that describe the principal research efforts conducted under the Base Program in five topic areas. Volume 2 describes tasks performed within the JSRP. Research conducted under this agreement has resulted in technology transfer of a variety of energy-related research information. A listing of related publications and presentations is given at the end of each research topic summary. More specific and detailed information is provided in the topical reports referenced in the related publications listings.

  3. Experimental comparison of biomass chars with other catalysts for tar reduction

    NARCIS (Netherlands)

    Abu El-Rub, Ziad; Bramer, Eduard A.; Brem, Gerrit

    2008-01-01

    In this paper the potential of using biomass char as a catalyst for tar reduction is discussed. Biomass char is compared with other known catalysts used for tar conversion. Model tar compounds, phenol and naphthalene, were used to test char and other catalysts. Tests were carried out in a fixed bed

  4. Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates

    International Nuclear Information System (INIS)

    Bryer, Pamela J.; Scoggins, Mateo; McClintock, Nancy L.

    2010-01-01

    Non-point-source pollution is a major source of ecological impairment in urban stream systems. Recent work suggests that coal-tar pavement sealants, used extensively to protect parking areas, may be contributing a large portion of the polycyclic aromatic hydrocarbon (PAH) loading seen in urban stream sediments. The hypothesis that dried coal-tar pavement sealant flake could alter the macroinvertebrate communities native to streams in Austin, TX was tested using a controlled outdoor laboratory type approach. The treatment groups were: control, low, medium, and high with total PAH concentrations (TPAH = sum of 16 EPA priority pollutant PAHs) of 0.1, 7.5, 18.4, and 300 mg/kg respectively. The low, medium, and high treatments were created via the addition of dried coal-tar pavement sealant to a sterile soil. At the start of the 24-day exposure, sediment from a minimally impacted local reference site containing a community of live sediment-dwelling benthic macroinvertebrates was added to each replicate. An exposure-dependent response was found for several stream health measures and for several individual taxa. There were community differences in abundance (P = 0.0004) and richness (P < 0.0001) between treatments in addition to specific taxa responses, displaying a clear negative relationship with the amount of coal-tar sealant flake. These results support the hypothesis that coal-tar pavement sealants contain bioavailable PAHs that may harm aquatic environments. - Coal-tar pavement sealants degrade stream invertebrate communities.

  5. 29 CFR 1910.1002 - Coal tar pitch volatiles; interpretation of term.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 6 2010-07-01 2010-07-01 false Coal tar pitch volatiles; interpretation of term. 1910.1002... Hazardous Substances § 1910.1002 Coal tar pitch volatiles; interpretation of term. As used in § 1910.1000 (Table Z-1), coal tar pitch volatiles include the fused polycyclic hydrocarbons which volatilize from the...

  6. Corrosion test by low-temperature coal tar

    Energy Technology Data Exchange (ETDEWEB)

    Ando, S; Yamamoto, S

    1952-01-01

    Corrosive actions of various fractions of low-temperature coal tar against mild steel or Cr 13-steel were compared at their boiling states. Corrosions became severe when the boiling points exceeded 240/sup 0/. The acidic fractions were more corrosive. In all instances, corrosion was excessive at the beginning of immersion testing and then gradually became mild; boiling accelerated the corrosion. Cr 13-steel was corrosion-resistant to low-temperature coal-tar fractions.

  7. Numerical simulation of fine oil sand tailings drying in test cells

    NARCIS (Netherlands)

    Vardon, P.J.; Nijssen, T.; Yao, Y.; Van Tol, A.F.

    2014-01-01

    As a promising technology in disposal of mature fine tailings (MFT), atmospheric fines drying (AFD) is currently being implemented on a commercial scale at Shell Canada’s Muskeg River Mine near Fort McMurray, Alberta. AFD involves the use of a polymer flocculent to bind fine particles in MFT

  8. Application of dry stackable tailings technologies : providing the base for reclamation

    Energy Technology Data Exchange (ETDEWEB)

    Mikula, R.J. [Natural Resources Canada, Devon, AB (Canada). CANMET Energy Technology Centre

    2010-07-01

    The tailings containment structures are some of the largest man made features on the planet. This presentation demonstrated that dry stackable tailings technology may reduce the volume of the accumulated fluid fine tailings. Dry stackable tailings can contribute to boreal forest reclamation and reduce water requirement from the Athabasca River. Much of the water used for the production of each barrel of bitumen is recycled. The water is tied up in the pore spaces of the mineral sand, silt, and clay component which forms the mature fine tailings (MFT) that are contained behind large dykes. Syncrude and Suncor have used a wide variety of technologies to create a dry stackable tailings from this fluid fine tailings substrate. The availability of dry stackable tailings will open options for reclamation strategies that end with the original wetlands or boreal forest. Some of the tailings management options that would lead to a dry stackable tailings naturally also significantly decrease the barrels of water lost with each barrel of bitumen production. These options were discussed along with an analysis of their impact on recycle and pore water quality and quantity. There is an opportunity to remove residual bitumen during the transfer of fluid fine tailings to recover water and create dry stackable tailings. If this bitumen removal is extensive enough, it might be possible to use the dry stackable tailings directly as a reclamation material. tabs., figs.

  9. Fish gill responses to pollutants from oil sands mining-associated waters

    International Nuclear Information System (INIS)

    Lee, L.E.J.; Willfang, S.; Lamb, M.P.; Nero, V.; Farwell, A.J.; Dixon, D.G.

    2002-01-01

    The processing of Athabasca Deposit oil sands results in large amounts of liquid wastes associated with oil sand tailings. In addition to containing polycyclic aromatic hydrocarbons (PAHs), these waste waters are high in salinity and naphthenic acids which may be toxic to aquatic biota and their effects must be clarified. This study presents a suite of tests for in-depth and quick analysis of tailings water toxicity and contributes to the assessment of environmental risk. Yellow perch, fathead minnows, and rainbow trout were exposed to reclamation ponds where both in vivo and in vitro evaluation of crude and individual naphthenic acids and salts were conducted to examine their effect on fish gills which are very susceptible to contaminants. The fish exposed to the reclamation ponds showed higher incidence of gill pathological changes than control fish in Mildred Lake, a reservoir lake whose waters are diverted for use in oil sands extraction. Notable gill histopathological changes were observed when fish were exposed in vivo to sulfate/chloride salts and to abietic acid. Changes in membrane integrity, lysosomal activity and general morphology were observed when fished were exposed in vitro to salts, commercial napthenic acids or crude naphthenic extracts from the reclamation ponds

  10. Effect of water addition in a microwave assisted thermal cracking of biomass tar models

    International Nuclear Information System (INIS)

    Warsita, Aris; Al-attab, K.A.; Zainal, Z.A.

    2017-01-01

    Highlights: • Effective tar thermal treatment with water addition using microwave is proposed. • The reactor temperature of 1200 °C can be reached quickly at bed height 120 mm. • The optimum water to tar ratio W/T was 0.3 for tar models. • Temperature greatly effect tar removal at various W/T rates. - Abstract: Producer gas from biomass gasification is plagued by the presence of tar which causes pipe blockages. Thermal and catalytic treatments in a microwave reactor have been shown to be effective methods in removing tar from producer gas. A question arises as to the possibility of enhancing the removal mechanism by adding water into the reactor. Toluene and naphthalene were used as tar models in the present study with N_2 as the carrier gas followed by the use of simulated producer gas. Thermal treatment with various amount of water was added at temperatures in the range of 800–1200 °C. The tar removal efficiency obtained 95.83% at the optimum temperature of 1200 °C for naphthalene in for toluene 96.32% at 1050 °C at water to tar ratio (W/T) of 0.3. This study shows that the removal of tar by microwave irradiation with water addition is a significant and effective method in tar cracking.

  11. Sampling of tar from sewage sludge gasification using solid phase adsorption.

    Science.gov (United States)

    Ortiz González, Isabel; Pérez Pastor, Rosa Ma; Sánchez Hervás, José Ma

    2012-06-01

    Sewage sludge is a residue from wastewater treatment plants which is considered to be harmful to the environment and all living organisms. Gasification technology is a potential source of renewable energy that converts the sewage sludge into gases that can be used to generate energy or as raw material in chemical synthesis processes. But tar produced during gasification is one of the problems for the implementation of the gasification technology. Tar can condense on pipes and filters and may cause blockage and corrosion in the engines and turbines. Consequently, to minimize tar content in syngas, the ability to quantify tar levels in process streams is essential. The aim of this work was to develop an accurate tar sampling and analysis methodology using solid phase adsorption (SPA) in order to apply it to tar sampling from sewage sludge gasification gases. Four types of commercial SPA cartridges have been tested to determine the most suitable one for the sampling of individual tar compounds in such streams. Afterwards, the capacity, breakthrough volume and sample stability of the Supelclean™ ENVI-Carb/NH(2), which is identified as the most suitable, have been determined. Basically, no significant influences from water, H(2)S or NH(3) were detected. The cartridge was used in sampling real samples, and comparable results were obtained with the present and traditional methods.

  12. Occupational coal tar dermatitis

    Energy Technology Data Exchange (ETDEWEB)

    Conde-Salazar, L; Guimaraens, D; Romero, L V; Gonzalez, M A

    1987-04-01

    The paper describes the allergic reaction to coal tar of a man handling it in a factory. The reaction appeared in the form of eczema on his trunk, arms and legs, but his hands were not affected as he had been wearing gloves. 1 ref.

  13. 179 Extraction of Coal-tar Pitch by Supercritical Carbon Dioxide ...

    African Journals Online (AJOL)

    Meyer

    Several extractions of coal-tar pitch were performed using supercritical fluid ..... pressure and temperature, unlike exhaustive extraction, which involves a change in ... mechanism that is operative on extracting coal-tar pitch components with.

  14. Sand dune of Ruby, Arizona, an anthropogenically created biodiversity hotspot for wasps and their velvet ant parasitoids

    Science.gov (United States)

    Justin O. Schmidt

    2013-01-01

    A large artificial sand dune composed of finely crushed mine tailings was produced by deep mining operations at Ruby, Arizona. Today, the ghost town of Ruby is an important historical location and biodiversity refuge, with the newly formed dune forming the core of the refuge. The dune provides ideal nesting habitat for at least 13 species of sand-loving wasps,...

  15. Contact sensitivity to newsprint: a rare manifestation of coal tar allergy

    Energy Technology Data Exchange (ETDEWEB)

    Illchyshyn, A; Cartwright, P H; Smith, A G

    1987-07-01

    Contact dermatitis due to coal tar is infrequently reported in spite of the fact that it consists of a mixture of 10,000 constituents, and is still often used to treat both eczema and psoriasis. Discusses patient with coal tar sensitivity in whom the source of exacerbation of her dermatitis is shown to be newsprint, a common product containing coal tar-derived material. 6 refs.

  16. Radiological survey of the inactive uranium-mill tailings at Green River, Utah

    International Nuclear Information System (INIS)

    Haywood, F.F.; Christian, D.J.; Ellis, B.S.; Hubbard, H.M. Jr.; Lorenzo, D.; Shinpaugh, W.H.

    1980-03-01

    The uranium-mill tailings at Green River, Utah, are relatively low in 226 Ra content and concentration (20 Ci and 140 pCi/g, respectively) because the mill was used to upgrade the uranium ore by separating the sand and slime fractions; most of the radium was transported along with the slimes to another mill site. Spread of tailings was observed in all directions, but near-background gamma exposure rates were reached at distances of 40 to 90 m from the edge of the pile. Water erosion of the tailings is evident and, since a significant fraction of the tailings pile lies in Brown's Wash, the potential exists for repetition of the loss of a large quantity of tailings such as occurred during a flood in 1959. In general, the level of surface contamination was low at this site, but some areas in the mill site, which were being used for nonuranium work, have gamma-ray exposure rates up to 143 μR/hr

  17. Coal tar phototoxicity: characteristics of the smarting reaction

    International Nuclear Information System (INIS)

    Diette, K.M.; Gange, R.W.; Stern, R.S.; Arndt, K.A.; Parrish, J.A.

    1985-01-01

    The properties and ultraviolet exposure parameters of tar smarts were examined in an effort to elucidate the mechanisms involved. It was show that irradiation with 1 minimal smarting dose (MSD) of UVA immediately following tar removal lowered the MSD for 6 h, demonstrated by subsequent challenge with UVA. Following 3 MSDs this memory effect was demonstrable for 24 h. The smarting reaction was area dependent--smaller areas of exposure require higher doses of UVA to induce smarting. Smarting followed reciprocity over a 6-fold range of irradiances (2-12.5 mW/cm2) but higher irradiances required higher doses of UVA, perhaps due to a delay in the recognition and reporting of smarting. The smarting reaction and delayed erythema due to UVA and tar were equally blocked by sunscreen

  18. Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Bryer, P.J.; Scoggins, M.; McClintock, N.L. [Lamar University, Beaumont, TX (United States). Dept. of Biology

    2010-05-15

    Non-point-source pollution is a major source of ecological impairment in urban stream systems. Recent work suggests that coal-tar pavement sealants, used extensively to protect parking areas, may be contributing a large portion of the polycyclic aromatic hydrocarbon (PAH) loading seen in urban stream sediments. The hypothesis that dried coal-tar pavement sealant flake could alter the macroinvertebrate communities native to streams in Austin, TX was tested using a controlled outdoor laboratory type approach. The treatment groups were: control, low, medium, and high with total PAH concentrations (TPAH = sum of 16 EPA priority pollutant PAHs) of 0.1, 7.5, 18.4, & 300 mg/kg respectively. The low, medium, and high treatments were created via the addition of dried coal-tar pavement sealant to a sterile soil. At the start of the 24-day exposure, sediment from a minimally impacted local reference site containing a community of live sediment-dwelling benthic macroinvertebrates was added to each replicate. An exposure-dependent response was found for several stream health measures and for several individual taxa. There were community differences in abundance (P = 0.0004) and richness (P < 0.0001) between treatments in addition to specific taxa responses, displaying a clear negative relationship with the amount of coal-tar sealant flake. These results support the hypothesis that coal-tar pavement sealants contain bioavailable PAHs that may harm aquatic environments.

  19. Chemical and physical characteristics of tar samples from selected Manufactured Gas Plant (MGP) sites

    International Nuclear Information System (INIS)

    Ripp, J.; Taylor, B.; Mauro, D.; Young, M.

    1993-05-01

    A multiyear, multidisciplinary project concerning the toxicity of former Manufactured Gas Plant (MGP) tarry residues was initiated by EPRI under the Environmental Behavior of Organic Substances (EBOS) Program. This report concerns one portion of that work -- the collection and chemical characterization of tar samples from several former MGP sites. META Environmental, Inc. and Atlantic Environmental Services, Inc. were contracted by EPRI to collect several samples of tarry residues from former MGP sites with varied historical gas production processes and from several parts of the country. The eight tars collected during this program were physically very different. Some tars were fluid and easily pumped from existing wells, while other tars were thicker, semi-solid, or solid. Although care was taken to collect only tar, the nature of the residues at several sites made it impossible not to collect other material, such as soil, gravel, and plant matter. After the samples were collected, they were analyzed for 37 organic compounds, 8 metals, and cyanide. In addition, elemental analysis was performed on the tar samples for carbon, hydrogen, oxygen, sulfur and nitrogen content and several physical/chemical properties were determined for each tar. The tars were mixed together in different batches and distributed to researchers for use in animal toxicity studies. The results of this work show that, although the tars were produced from different processes and stored in different manners, they had some chemical similarities. All of the tars, with the exception of one unusual solid tar, contained similar relative abundances of polycyclic aromatic hydrocarbons (PAHs)

  20. Thermodynamic analysis of tar reforming through auto-thermal reforming process

    Energy Technology Data Exchange (ETDEWEB)

    Nurhadi, N., E-mail: nurhadi@tekmira.esdm.go.id; Diniyati, Dahlia; Efendi, M. Ade Andriansyah [R& D Centre for Mineral and Coal Technology, Jln. Jend.Sudirman no. 623, Bandung. Telp. 022-6030483 (Malaysia); Istadi, I. [Department of Chemical Engineering, Diponegoro University, Jln. Jl. Prof. Soedarto, SH, Semarang (Malaysia)

    2015-12-29

    Fixed bed gasification is a simple and suitable technology for small scale power generation. One of the disadvantages of this technology is producing tar. So far, tar is not utilized yet and being waste that should be treated into a more useful product. This paper presents a thermodynamic analysis of tar conversion into gas producer through non-catalytic auto-thermal reforming technology. Tar was converted into components, C, H, O, N and S, and then reacted with oxidant such as mixture of air or pure oxygen. Thus, this reaction occurred auto-thermally and reached chemical equilibrium. The sensitivity analysis resulted that the most promising process performance occurred at flow rate of air was reached 43% of stoichiometry while temperature of process is 1100°C, the addition of pure oxygen is 40% and preheating of oxidant flow is 250°C. The yield of the most promising process performance between 11.15-11.17 kmol/h and cold gas efficiency was between 73.8-73.9%.The results of this study indicated that thermodynamically the conversion of tar into producer gas through non-catalytic auto-thermal reformingis more promising.

  1. Pelagic tar and plastic in the Gulf of Alaska and Bering Sea: 1975

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, D G

    1977-07-01

    Seventy-one tows of 740 m/sup 2/ each were made in search of pelagic tar and plastics in the Gulf of Alaska and Bering Sea during the period October 1974 to October 1975. Tar was observed on nine occasions while plastics were found six times. The arithmetic mean value of tar abundance, 3.3 x 10/sup -3/ mg/m/sup 2/, is considerably lower than most other oceanic areas for which values have been reported. Gas chromatographic analysis of this tar indicates that it is more extensively weathered than tar from the north Atlantic. An estimate of the abundance of tar lumps too small to be sampled by net tows is made based on the assumption that there are equal weights of particles in logarithmetically equal size intervals. The abundance of pelagic plastics is also low.

  2. Preliminary fingerprinting analysis of Alberta oil sands and related petroleum products

    International Nuclear Information System (INIS)

    Yang, C.; Wang, Z.D.; Hollebone, B.; Brown, C.E.; Yang, Z.Y.; Landriault, M.; Fieldhouse, B.

    2009-01-01

    This paper reported on a study that presented a preliminary quantitative chemical characterization of Alberta oil sands and many other related Alberta oils such as oil sand bitumen, Cold Lake bitumen, Albian heavy synthetic crude, and Alberta Mixed sweet blend. The rapid increase in production of the Alberta oil sands has resulted in unprecedented environmental concern. The mining, extraction and production of oil sands such resulted in huge consumption of water resources, huge emission of greenhouse gas and large number of tailings ponds. In addition, accidental spills in the transportation and usage of oil sands will potentially cause considerable impact on the environment. It is therefore essential to have the ability to characterize Alberta oil sands and their oil products. The specific chemical properties of the oil sands bitumen must be known. Therefore, this study collected quantitative data on the concentration and distribution profiles of target compounds in Alberta oil sands and its petroleum products. The chemical fingerprints of 5 Alberta oil sands and their related petroleum products were studied using gas chromatography/flame ionization detection (GC/FID) and gas chromatography/mass spectrometry (GC/MS). The characterized hydrocarbons were n-alkanes; target alkylated PAHs and other EPA priority PAHs; biomarker terpanes and steranes; and bicyclic sesquiterpanes. The information acquired during this study will provide the basis for oil-oil correlation and differentiation in future environmental applications relevant to oil sands. 24 refs., 6 tabs., 4 figs.

  3. Soil arthropod fauna from natural ecosites and reclaimed oil sands soils in northern Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Battigelli, J.P.; Leskiw, L.A. [Paragon Soil and Environmental Consulting Inc., Edmonton, AB (Canada)

    2006-07-01

    An understanding of soil invertebrates may facilitate current reclamation activities in the oil sands region of Alberta. This paper presented the results of a study investigating the density, diversity, and structure of soil arthropod assemblages in natural habitats and reclaimed sites. The purpose of the study was to establish a baseline inventory of soil arthropod assemblages in order to enable long-term monitoring of soil arthropod recolonization in disturbed sites. Nine natural ecosites were sampled for the study, including peat mix over secondary material over tailing sand; direct placement over tailing sand; peat mix over secondary over overburden; direct placement over overburden; peat mix over tailing sand; and peat mix over overburden. Samples were collected from previously established long-term soil and vegetation treatment plots in both natural ecosites and reclaimed soil sites located near Fort McMurray, Alberta. Results showed that densities of mesofauna were significantly higher in samples collected from natural ecosites. Acari and Collembola represented approximately 97 to 98 per cent of the fauna collected. It was also noted that the overall structure of the soil mesofauna community differed between natural soils and reclaimed soils. A significant reduction in the abundance of oribatid mites was observed in soils that had been reclaimed for over 34 years. Changes in the soil mesofauna community structure suggested that reclaimed soils continue to represent disturbed ecosites, as was indicated by higher proportions of prostigmatid mites and some collembolan families. Differences in community structure may influence soil ecosystem functions, including decomposition rates; nutrient recycling; soil structure; and fungal and bacterial biomass. It was concluded that further research is needed to examine oribatid mites and collembolan species diversity and community structure in reclaimed soils. 18 refs., 6 figs.

  4. Extraction of low-temperature tar by various alcohols

    Energy Technology Data Exchange (ETDEWEB)

    Hara, N; Osawa, M; Azuma, H

    1948-01-01

    MeOH was the most effective of the alcohols tested (MeOH to pentanol) in extracting acid components from low-temperature tar. The optimum concentrations of MeOH were 70 to 80% for 1 extraction and 70 to 75% for repeated or continuous extractions when the solvent-tar ratio was 1:1. By 2 to 3 extractions neutral oil could be separated in about 90% yield including > 3% acidic oil.

  5. Radiation protection in the sand pit

    International Nuclear Information System (INIS)

    Hewson, Greg

    1997-01-01

    Radiation protection in the Western Australian minerals sands industry has attracted considerable controversy over the last 20 years: firstly, in relation to environmental and public health issues associated with the indiscriminate disposal of radioactive tailings as landfill in the mid to late 1970s and, secondly, in relation to occupational health issues associated with excessive radiation exposures to some workers at some plants in the mid to late 1980s. The industry also attracts attention through its proximity to coastal regions and population centres and consequent land use conflicts. Owing to intense political and societal scrutiny, and the emotional responses evoked by radiation, the industry's survival depends on a continuing high level of environmental and safety performance. This article summarises the successes and failures of the mineral sands industry in managing radiation protection and highlights some future issues and challenges for the industry. (Author)

  6. Deciphering structure-activity relationships in a series of Tat/TAR inhibitors.

    Science.gov (United States)

    Pascale, Lise; González, Alejandro López; Di Giorgio, Audrey; Gaysinski, Marc; Teixido Closa, Jordi; Tejedor, Roger Estrada; Azoulay, Stéphane; Patino, Nadia

    2016-11-01

    A series of pentameric "Polyamide Amino Acids" (PAAs) compounds derived from the same trimeric precursor have been synthesized and investigated as HIV TAR RNA ligands, in the absence and in the presence of a Tat fragment. All PAAs bind TAR with similar sub-micromolar affinities but their ability to compete efficiently with the Tat fragment strongly differs, IC50 ranging from 35 nM to >2 μM. While NMR and CD studies reveal that all PAA interact with TAR at the same site and induce globally the same RNA conformational change upon binding, a comparative thermodynamic study of PAA/TAR equilibria highlights distinct TAR binding modes for Tat competitor and non-competitor PAAs. This led us to suggest two distinct interaction modes that have been further validated by molecular modeling studies. While the binding of Tat competitor PAAs induces a contraction at the TAR bulge region, the binding of non-competitor ones widens it. This could account for the distinct PAA ability to compete with Tat fragment. Our work illustrates how comparative thermodynamic studies of a series of RNA ligands of same chemical family are of value for understanding their binding modes and for rationalizing structure-activity relationships.

  7. The use of a large-strain consolidation model to optimise multilift tailing deposits

    NARCIS (Netherlands)

    Vardon, P.J.; Yao, Y.; Van Paassen, L.A.; Van Tol, A.F.

    2015-01-01

    Thin-lift atmospheric fine drying (AFD) is a technique used to dewater mine and oil sand tailings, which utilises both self-weight consolidation and atmospheric evaporation. The disposed layers undergo a cyclic drying and rewetting process due to precipitation and deposition of additional lifts on

  8. Diffusion of radon in candidate soils for covering uranium-mill tailings

    International Nuclear Information System (INIS)

    Kalkwarf, D.R.; Silker, W.B.

    1984-01-01

    Diffusion coefficients were measured for radon in 34 soils that had been identified by uranium mill personnel as candidate soils for covering their tailings piles in order to reduce radon emission. The coefficients referred to diffusion in the total pore space of the soils. They were measured by a steady-state method using soil columns compacted to greater than 80% of their Proctor maximum packing densities, but with moisture contents generally less than would be expected at a tailings site. Three published empirical equations relating diffusion coefficients to soil moisture and porosity were tested with these data. The best fit was obtained with the equation: D = 0.70 exp [-4(m-mP - +m 5 )] in which P is the dry porosity of the soil and m is its moisture saturation, e.e. the fraction of pore volume filled with water. This equation was used to extrapolate measured coefficients to values expected at soil-moisture contents representative of tailings sites in the western United States. Extrapolated values for silty sands and clayey sands ranged from 0.004 to 0.06 cm 2 /s where w, the weight ratio of water to dry soil, is expected to vary from 0.04 to 0.09. Values for inorganic silts and clays ranged from 0.001 to 0.02 cm 2 /s where w is expected to vary from 0.10 to 0.13

  9. Dermal uptake of polycyclic aromatic hydrocarbons after hairwash with coal-tar shampoo

    Energy Technology Data Exchange (ETDEWEB)

    Schooten, F.-J. van; Moonen, E.J.C.; Rhijnsburger, E.; Agen, B. van; Thijssen, H.H.W.; Kleinjans, J.C.S. [University of Limburg, Maastricht (Netherlands). Dept. of Health Risk Analysis and Toxicology

    1994-11-26

    Describes an experiment to assess the dermal uptake of polycyclic aromatic hydrocarbons (PAHs) after hairwashing with coal tar antidandruff shampoo. The urinary excretion of 1-hydroxypyrene (1-OH-P), a PAH metabolile was used to assess internal dose of PAH. A single use of coal tar shampoo resulted in increased 1-OH-P excretion in all members of the experimental group compared with the control group using a non-coal tar antidandruff shampoo. It is suggested that repeated use of coal tar shampoo would result in a high internal dose of carcinogenic PAH. 5 refs., 1 fig.

  10. Iron-based materials as tar cracking catalyst in waste gasification

    Energy Technology Data Exchange (ETDEWEB)

    Nordgreen, Thomas

    2011-07-01

    The treatment of municipal solid waste (MSW) in Sweden has changed during the past decades due to national legislation and European Union directives. The former landfills have more or less been abandoned in favour of material recycling and waste incineration. On a yearly basis approximately 2.2 million tonnes waste are incinerated in Sweden with heat recovery and to some extent also with electricity generation, though at a low efficiency. It is desirable to alter this utilisation and instead employ MSW as fuel in a fluid bed gasification process. Then electrical energy may be produced at a much higher efficiency. However, MSW contain about 1 % chlorine in the form of ordinary table salt (NaCl) from food scraps. This implies that the tar cracking catalyst, dolomite, which is normally employed in gasification, will suffer from poisoning if applied under such conditions. Then the tar cracking capacity will be reduced or vanish completely with time. Consequently, an alternative catalyst, more resistant to chlorine, is needed. Preliminary research at KTH has indicated that iron in its metallic state may possess tar cracking ability. With this information at hand and participating in the project 'Energy from Waste' an experimental campaign was launched. Numerous experiments were conducted using iron as tar cracking catalyst. First iron sinter pellets from LKAB were employed. They were reduced in situ with a stream of hydrogen before they were applied. Later iron-based granules from Hoeganaes AB were tested. These materials were delivered in the metallic state. In all tests the KTH atmospheric fluidised bed gasifier with a secondary catalytic reactor housing the catalytic material was deployed. Mostly, the applied fuel was birch. The results show that metallic iron possesses an intrinsic ability, almost in the range of dolomite, to crack tars. Calculations indicate that iron may be more resistant to chlorine than dolomite. The exploration of metallic iron

  11. Secondary reactions of tar during thermochemical biomass conversion[Dissertation 14341

    Energy Technology Data Exchange (ETDEWEB)

    Morf, P.O.

    2001-07-01

    This dissertation submitted to the Swiss Federal Institute of Technology in Zurich presents and discusses the results obtained during the examination of the processes involved in the formation and conversion of tar in biomass gasification plant. Details are given on the laboratory reactor system used to provide separated tar production and conversion for the purposes of the experiments carried out. The results of analyses made of the tar and the gaseous products obtained after its conversion at various temperatures are presented. The development of kinetic models using the results of the experiments that were carried out is described. The results of the experiments and modelling are compared with the corresponding results obtained using a full-scale down-draft, fixed-bed gasifier. The author is of the opinion that the reaction conditions found in full-scale gasifiers can be well simulated using heterogeneous tar conversion experiments using the lab reactor system.

  12. The Influences of Iron Ore Tailings as Fine Aggregate on the Strength of Ultra-High Performance Concrete

    Directory of Open Access Journals (Sweden)

    Zhigang Zhu

    2015-01-01

    Full Text Available The present study looks for the feasibility of preparing UHPC with iron ore tailings (IOT for short as fine aggregate. To enhance outstanding high performances, some influences on UHPC mortars were investigated such as different kinds of sands, different mix ratio of sands, and different largest particle size of fine aggregate. The results show that IOT have negligible poorer aggregate performance than silica sands but better than river sands. The strength of UHPC reaches the highest point when silica sands were instead 60% by IOT. As the largest particle size of fine aggregate is decreasing, the strength and frost resistance of UHPC were improved, but the liquidity was decreased. Micropowder of IOT affects the strength and the optimal content was 4%.

  13. Tar loads on Omani beaches

    International Nuclear Information System (INIS)

    Badawy, M.I.; Al-Harthy, F.T.

    1991-01-01

    Owing to Oman's geographic position and long coastal line, the coastal areas of Oman are particularly vulnerable to oil pollution from normal tanker operations, illegal discharges, and accidental spills as well as local sources of oil input. UNEP carried out a survey on the coasts of Oman to determine the major sources of oil pollution and concluded that the major shoreline pollution problems in Oman arose from operational discharges of oil from passing vessels traffic. The oil, because of the high sea and air temperatures in the area, was subjected to relatively high rates of evaporation and photo-oxidation and tended to arrive at the coast as heavy petroleum particulate residues (tar balls). The aim of the present study was to measure the loads of tar balls in Omani coastal areas and to identify the source of oil pollutants on beaches

  14. Decomposition of tar in gas from updraft gasifier by thermal cracking

    DEFF Research Database (Denmark)

    Brandt, Peder; Henriksen, Ulrik Birk

    2000-01-01

    Continuing earlier work with tar reduction by partial oxidation of pyrolysis gas [1] thermal cracking has been evaluated as a gas cleaning process. The work has been focusing on cleaning gas from updraft gasifiers, and the long term purpose is to develop a tar cleaning unit based on thermal...... cracking. An experimental set-up has been built, in which a flow of contaminated gas can be heated up to 1290°C in a reactor made of pure Al2O3. Four measurements were made. Three with gas from a pyrolysis unit simulating updraft gasifier, and one with gas from an updraft gasifier. Cracking temperatures...... was 1200, 1250 and 1290°C, and the residence time at this temperature was 0.5 second. The measurements show that at the selected residence time of 0.5 second, the gas flow in a thermal tar cracking unit has to be heated to at least 1250°C to achieve sufficient tar cleaning. At 1290°C, a tar content as low...

  15. Flow behaviour and robustness of non-segregating tailings made from filtered/centrifuged MFT

    Energy Technology Data Exchange (ETDEWEB)

    Nik, R.M.; Sego, D.C.; Morgenstern, N.R. [Alberta Univ., Edmonton, AB (Canada). Geotechnical Center

    2010-07-01

    This PowerPoint presentation described an experimental study of a centrifugal dewatering filtration process for mature fine tailings (MFT). Various MFT samples from different oil sands operations were pumped into a filtering centrifuge that produced cake, thin tailings, and filtrate. The MFT was then transformed into non-segregated tailings (NST) and composite tailings (CT). The depositional characteristics of the CT-NST samples were evaluated in a series of flume tests. Flow profiles were presented for various samples. Vane shear tests were also conducted. The yield stress of each sample was compared with its flow duration and solids content. The results of the experimental tests demonstrated that the centrifugal filtration process can be considered as the initial stage of a multi-stage tailings management plan. The filtering centrifuge method can be used to produce robust CTs with higher solids content. Use of the method can decrease the amount of coagulants or flocculants required for further treatment. tabs., figs.

  16. Athabasca--special report No. 2, sand behavior key to operation size

    Energy Technology Data Exchange (ETDEWEB)

    Daly, W J

    1966-09-01

    Before production of the crude oil from the Athabasca tar sands could be initiated, a feasibility and economic study based on field test work was made. It was concluded that the project was technically feasible and a plant could be constructed for approximately $137 million, but that the engineering design must be preceded by a field test program, laboratory work, and by ground surveys. A test program, using the hot water recovery process and sized to handle 3 tons of sand per hour, was begun in Oct. 1963. As the test program proceeded, the unit was frequently renovated as capacity was increased from 3 tons to finally 10 tons per hour. Included in the tests was the determination of the effect that raw bitumen pools (indicated by the government coring program) would have on production operations. It was determined that no problems would arise from this situation because no such pools could be found and were considered not to be in existence. The test model was successful in clearly illustrating the principles to use in the overall layout, which is approximately 50% complete.

  17. Monitoring of tar contents in gases. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, Finn [ChimneyLab Europe ApS, Hadsten (Denmark); Houmann Jakobsen, H. [BioSynergi Proces ApS, Hoersholm (Denmark)

    2012-08-15

    The purpose of this project is to develop and test a relative cheap and simple online tar measuring method, which can monitor the tar content in product gas from thermal gasification. The measuring principle is absorption of tar from sample gas in Isopropanol (IPA), and measuring on this solution by UV-spectrophotometer. Continuous sampling of tar containing producer gas turned out to be a larger problem than earlier foreseen. The best solution was decided to be sampling with higher flows, and afterwards cleaning the IPA in activated carbon. The ambitions for continuous sampling had to be decreased to 1 week, where the IPA and the activated carbon is contaminated by tar and has to be replaced. However this requires larger amounts of IPA and activated carbon. For IPA the weekly consumption was 12-15 Litres and for activated carbon 10 Litres. The whole analyzer unit turned out to be more complex than first projected, mainly because of the increased amounts of IPA. The best mist filter, with respect to pressure drop, efficiency and retention time is a combination of glass wool and quarts wool. The unit has been tested on gas; 20 kW pellets burner for 116 hours. Harbooere updraft gasifier for 519 hours. Skive fluid bed gasifier for 879 hours. There have during the project period been several simple practical problems such as bubbles in the IPA, increasing pressure drop over the activated carbon bed, dropout of UV data acquisition program and increasing baseline. The principle showed from the beginning some good results, with the limitation of 1 week continuous operation, but at the 5. period in Skive the baseline was increasing all the time, and it was not possible to solve this problem. (LN)

  18. Modelling the low-tar BIG gasification concept[Biomass Integrated gasification

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Lars; Elmegaard, B.; Qvale, B.; Henriksen, Ulrrik [Technical univ. of Denmark (Denmark); Bentzen, J.D.; Hummelshoej, R. [COWI A/S (Denmark)

    2007-07-01

    A low-tar, high-efficient biomass gasification concept for medium- to large-scale power plants has been designed. The concept is named 'Low-Tar BIG' (BIG = Biomass Integrated Gasification). The concept is based on separate pyrolysis and gasification units. The volatile gases from the pyrolysis (containing tar) are partially oxidised in a separate chamber, and hereby the tar content is dramatically reduced. Thus, the investment, and running cost of a gas cleaning system can be reduced, and the reliability can be increased. Both pyrolysis and gasification chamber are bubbling fluid beds, fluidised with steam. For moist fuels, the gasifier can be integrated with a steam drying process, where the produced steam is used in the pyrolysis/gasification chamber. In this paper, mathematical models and results from initial tests of a laboratory Low-Tar BIG gasifier are presented. Two types of models are presented: 1. The gasifier-dryer applied in different power plant systems: Gas engine, Simple cycle gas turbine, Recuperated gas turbine and Integrated Gasification and Combined Cycle (IGCC). The paper determines the differences in efficiency of these systems and shows that the gasifier will be applicable for very different fuels with different moisture contents, depending on the system. 2. A thermodynamic Low-Tar BIG model. This model is based on mass and heat balance between four reactors: Pyrolysis, partial oxidation, gasification, gas-solid mixer. The paper describes the results from this study and compares the results to actual laboratory tests. The study shows, that the Low-Tar BIG process can use very wet fuels (up to 65-70% moist) and still produce heat and power with a remarkable high electric efficiency. Hereby the process offers the unique combination of large scale gasification and low-cost gas cleaning and use of low-cost fuels which very likely is the necessary combination that will lead to a breakthrough of gasification technology. (au)

  19. Structural and dynamic characterization of the upper part of the HIV-1 cTAR DNA hairpin

    OpenAIRE

    Zargarian, Loussin?; Kanevsky, Igor; Bazzi, Ali; Boynard, Jonathan; Chaminade, Fran?oise; Foss?, Philippe; Mauffret, Olivier

    2009-01-01

    First strand transfer is essential for HIV-1 reverse transcription. During this step, the TAR RNA hairpin anneals to the cTAR DNA hairpin; this annealing reaction is promoted by the nucleocapsid protein and involves an initial loop?loop interaction between the apical loops of TAR and cTAR. Using NMR and probing methods, we investigated the structural and dynamic properties of the top half of the cTAR DNA (mini-cTAR). We show that the upper stem located between the apical and the internal loop...

  20. Estimation of particle size distribution in Athabasca oil sands by indirect neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Schutte, R.; Thompson, G.R.; Donkor, K.K. [New Caledonia College, Prince George, BC (Canada). Dept. of Chemistry; Duke, M.J.M. [Alberta Univ., Edmonton, AB (Canada). SLOWPOKE Nuclear Reactor Facility; Cowles, R. [Syncrude Canada, Edmonton, AB (Canada); Li, X.P.; Kratochvil, B. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemistry

    1999-10-01

    Knowledge concerning the particle size distribution (PSD) of oil sands is necessary for optimal extraction of bitumen from the sand, and it indicates ore quality, gives a measure of process performance during bitumen extraction, and yields information useful for tailings management. Oil sands with mainly coarse particulates are usually bitumen rich and easy to process in the conventional hot water extraction process. These ores do not require the addition of sodium hydroxide as a process aid, and tailings volumes are minimal in contrast to high fines oil sands. Compared to the methods currently in use for determining the PSD in the oil sand industry, a method is described that is rapid, simple to carry out, and does not involve the use of organic solvents with attendant disposal problems. The principle behind the method is the development of a set of correlations by applying regression analysis to a large set of PSD and elemental analysis data. Predicted PSDs compare favorably with results obtained by existing methods. Each of the three PSD methods currently in use could be simulated by the INAA method. The INAA-based model that predicts hydrometer equivalent data was only applicable above certain lower limits for the amount of the fine size fractions present because of the limited sensitivity of the hydrometer method for PSD determination of fine fractions. For all six particle sizes studied, the INAA model had lower overall uncertainty than the corresponding Microtrac and Coulter instrument methods; the instrument repeatability of the INAA fell between those of Microtrac and Coulter. For Athabasca oil sands, the INAA-based method for PSD determination at and below 44 microm afforded results comparable to current Microtrac and Coulter methods. 13 refs., 9 tabs., 2 figs.

  1. The separate effects of tar and nicotine on the cigarette smoking manoeuvre

    International Nuclear Information System (INIS)

    Woodman, G.; Newman, S.P.; Paiva, D.; Clarke, S.W.

    1987-01-01

    The separate effects of tar and nicotine on the cigarette smoking manoeuvre were investigated. Each of ten asymptomatic habitual smokers smoked three different commercially available cigarettes in a randomised order. The brands were chosen such that two had the same tar yield (10 mg) and two had the same nicotine yield (1.4 mg). The volume of smoke inhaled into the lungs was measured by tracing the smoke with the inert gas 81 Kr m . Puffing indices were recorded using an electronic smoking analyser and flowhead/cigarette holder. There was no difference in the total volume of smoke puffed from each of the cigarette brands. With cigarettes of the samme tar level, the total inhaled smoke volume was lower with the higher nicotine cigarette (P<0.05): by contrast, with cigarettes of the same nicotine level, the toal inhaled smoke volume was lower with the lower tar cigarette (P<0.02). Tar and nicotine appear to exercise independent control over the volume of smoke inhaled. (author)

  2. Crucial advantages of tail use in the evolution of vertebrate terrestrial locomotion

    Science.gov (United States)

    Astley, Henry; McInroe, Benjamin; Kawano, Sandy; Blob, Rick; Goldman, Daniel

    In the invasion of terrestrial environment, the first tetrapods faced the challenge of locomotion on flowable substrates (e.g. sand and mud), sometimes oriented at inclines. Although the morphology of many early tetrapods is known, robotic studies have revealed that effective locomotion on these substrates also depends strongly upon kinematics; slight differences in movements of the same appendage can lead to success or failure. Using a model organism (the mudskipper) and a robotic physical model, we demonstrate how muscular tails provided critical locomotor advantages on granular substrates that the first invaders of land likely encountered. Mudskippers use their tails for additional propulsion with increasing frequency as the slope of the granular material increases, and the decline in locomotor performance with slope is shallower when the tail is used. Experiments with a robotic model of the mudskipper showed that, while the tail did not always provide a benefit to locomotion, use of the tail made the robot's performance more robust, achieving effective locomotion on a wider range of slopes, limb postures and foot placements. These results suggest that, rather than simply being an inert appendage, the tails of early tetrapods were vital to their first forays into terrestrial habitats.

  3. Conceptual design of a remote system for characterizing oilsands tailings deposits

    Energy Technology Data Exchange (ETDEWEB)

    Lipsett, M.G.; Rivard, B. [Alberta Univ., Edmonton, AB (Canada). Dept. of Mechanical Engineering; Alberta Univ., Edmonton, AB (Canada). Dept. of Earth and Atmospheric Sciences

    2010-07-01

    This PowerPoint presentation described the design of a remote system for characterizing oil sands tailings deposits. The wheeled mobile robot technology was developed in order to improve the trafficability of composite tailings (CT) and other engineering tailings deposits, as well as to identify differences in feedstocks and process performance, and to determine shear strength losses from dynamic loading. The technology was comprised of a spectroscopy component, and a mobile robot equipped with surface measurement sensors. The control system included navigation and traction control devices. A communication component was also included. Tools used in the system included a penetrometer, a viscosimeter, and an automatic sample collection device. Tests have been conducted to determine the system's driving ability. Further tests are being conducted to evaluate the performance of the robot sensors and controllers. tabs., figs.

  4. Geotechnical parameters and behaviour of uranium tailings

    International Nuclear Information System (INIS)

    Matyas, E.L.

    1984-01-01

    The results of laboratory and in situ testing and test blasting, the observations made on a test embankment, and a description of actual construction practice associated with engineering studies for the management of uranium mill tailings at Elliot Lake, Ontario are presented. Relative density values inferred from standard penetration tests and cone penetrometer tests are shown to be inconsistent with relative density values determined from maximum and minimum void ratios. Some of the data contradicts existing correlations. The compressibility of in situ saturated tailings is presented in graphical form in terms of void ratio, vertical effective stress, and mean grain size. Hydraulic conductivity is shown to range over many orders of magnitude, depending on the void ratio. The observations on an instrumental test embankment are used to explain the appropriate selection of geotechnical parameters that gave good agreement between back-calculated and observed settlements. One-dimensional consolidation theory was found to be valid for the embankment case. It is necessary to account for changes in soil properties that occur during the consolidation process in order to obtain a good fit between back-calculated and observed settlements. The successful use of tailings sand for embankment construction is described. On the basis of normalized standard penetration resistance values, it is concluded that localized zones of saturated tailings may be prone to liquefaction under predicted earthquake loadings

  5. 21 CFR 740.18 - Coal tar hair dyes posing a risk of cancer.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Coal tar hair dyes posing a risk of cancer. 740.18... (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS Warning Statements § 740.18 Coal tar hair dyes... coal tar hair dye containing any ingredient listed in paragraph (b) of this section shall bear, in...

  6. Gasification of municipal solid waste in a downdraft gasifier: Analysis of tar formation

    Directory of Open Access Journals (Sweden)

    Tabitha Geoffrey Etutu

    2016-04-01

    Full Text Available In this study, municipal solid waste (MSW from a dumpsite was converted into refuse derived fuel (RDF and used as feedstock for an air-blown gasification process. The gasification process was conducted in a 10 kg.hr -1 downdraft gasifier at different air flow rates of 300, 350, 400, 450 and 550 NL.min1 at atmospheric pressure in order to investigate the quantity and quality of tar formed. It was shown that the increase in the air flow rate from 300 NL.min1 to 550 NL.min1 led to an increase in the oxidation temperature from 719°C to 870°C and an increase in the reduction temperature from 585°C to 750°C, respectively. Tar was reduced from 15 g.Nm3 to 4.7 g.Nm3 respectively. Heavy tar compounds (>C17 e.g. pyrene and phenathrene, decreased with the increase in the light tar compounds (tar reduction through a tar cracking process.

  7. Health assessment of tree swallows (Tachycineta bicolor) on the oil sands using stress, immune function and growth indicators

    Energy Technology Data Exchange (ETDEWEB)

    Harms, N.J.; Smits, J.E. [Saskatchewan Univ., Saskatoon, SK (Canada)

    2009-07-01

    Oil sand mining companies in Alberta continue to explore reclamation strategies for tailings water and are evaluating the ecological effectiveness of constructed wetlands for the bioremediation of liquid and solid tailings contaminated with naphthenic acids, polycyclic aromatic hydrocarbons, and dissolved inorganic ions. The success of reclaimed sites and ecosystem health can be measured by examining health variables in wild tree swallows (Tachycineta bicolor) nesting on experimental wetlands receiving tailings or water from tailings ponds. This presentation reported on a study that measured clutch size, egg mass, and hatching and fledging success of 40 breeding pairs of tree swallows on 3 experimental wetlands on Suncor Energy Inc. and Syncrude Canada Ltd. oil sands leases. The Shallow Wetlands/Demonstration Pond (Syncrude), Consolidated Tailings and Natural Wetlands (Suncor) represent sites of different ages and different categories of wetland reclamation, notably mature, maturing, and newly reclaimed. Due to lack of nesting success on the selected reference site, the Shallow Wetlands/Demonstration Pond was selected as the reference site because it has undergone nearly complete bioremediation and had a very low level of contamination. Nestling growth and survival were measured in 199 tree swallows nestlings on the 3 experimental wetlands. Two mid-weight nestlings from 12 nest boxes on each study site were also examined for feather corticosterone levels and adaptive immune function.

  8. Yellow perch embryo-larval survival and growth in surface waters associated with oil-sands mining

    International Nuclear Information System (INIS)

    Peters, L.E.; Heuvel, M.R. van den; Dixon, D.G.; Power, M.; Boerger, H.; MacKinnon, M.D.; Meer, T. Van

    1995-01-01

    As part of their land reclamation strategy, Syncrude Canada Ltd. is currently developing environmentally acceptable tailings disposal methods. Fine tailings, a suspension of clay and residual bitumen, is the waste product from oil sands extraction. Fine-tailings contain naphthenic acids, a group of saturated aliphatic and alicyclic carboxylic acids, which occur naturally in petroleum and are partly responsible for the toxicity of process water. The wet landscape method involves covering fine tails with a layer of water such that a self-sustaining ecosystem can be established. A 5 ha demonstration pond with a bottom of fine-tailings was constructed and stocked with yellow perch for experimental purposes. Two other reclaimed ponds formed with oil-sands overburden material were also stocked with perch. Adult perch sampled in the fall of 1995 from the experimental and reclaimed ponds exhibited a 2-fold induction of MFO activity compared to the source lake; indicating organic compound exposure. Perch from one of the reclaimed ponds showed significantly reduced circulating reproductive hormone levels, gonad size and smaller ovarian follicles. Reproductive parameters were not different between the source lake and the remaining ponds. Paired lab and field experiments were conducted to determine if contaminants present would be detrimental to egg viability and development of larvae either through direct exposure of spawned eggs or indirectly by effecting oogenesis. An early life stage toxicity test was also performed using commercially available naphthenic acid standard. Endpoints measured were percent fertilization, percent hatch, mortality, deformities, timing of developmental periods and larval growth

  9. Recovery of very viscous lubricating oils from shale-tar, etc

    Energy Technology Data Exchange (ETDEWEB)

    Erdmann, E

    1919-09-10

    Modification of the process covered by German Patent 335,190 for recovering very viscous lubricating oils, consisting, in place of brown-coal tar, deparafinned peat tar being subjected to the treatment with superheated steam from about 200 to 250/sup 0/C or to heating in vacuum at a temperature below 250/sup 0/C.

  10. Mill tailings disposal and environmental monitoring at the Ningyo-Toge uranium processing pilot plant

    International Nuclear Information System (INIS)

    Iwata, I.; Kitahara, Y.; Takenaka, S.; Kurokawa, Y.

    1978-01-01

    The tailings from the uranium processing pilot plant with a maximum ore processing capacity of 50 t/d are transferred to a tailings dam. The overflow from the dam is chemically treated and through settling ponds, sand filters to be discharged into a river. The concentrations of U, 226 Ra, pH, S.S., COD, Fe, Mn, Cl and F were monitored periodically and they were all below the control values. The results of monitoring on the river bed and rice paddy soil showed no signs of accumulation of U and 226 Ra in it

  11. Technological changes illustrated by the coal tar and tar dye industry; Die Wandlung der Technik am Beispiel der Steinkohlenteer- und Teerfarben-Chemie

    Energy Technology Data Exchange (ETDEWEB)

    Collin, G. [Deutsche Gesellschaft fuer Chemisches Apparatewesen, Chemische Technik und Biotechnologie e.V. (DECHEMA), Frankfurt am Main (Germany)

    2001-05-01

    Coal tar was detected in the 17th century in laboratory experiments based on empirical knowledge. In the 18th century industrial revolution, coal tar was an undesired by-product of iron production and coking plants. It was first used in the 19th century for impregnating railway sleepers. Later developments in atomic theory, new chemical symbols and organic element analysis provided the basis for discovering and chemical characterisation of coal tar constituents. Laboratory experiments with these tar constituents resulted in the first synthetic dyes, the postulation of tetravalent carbon and the resulting structural theory in organic chemistry for systematic synthesis of many tar dyes to substitute natural dyes in the textile industry. The technical application of these syntheses was part 2 of the industrial revolution and the foundation of the chemical industry in Germany, which developed rapidly in the 2nd half of the 19th century. Tar dye chemistry has made a significant contribution to Germany's economic growth and the change from an agricultural to an industrialized country. [German] Die Entdeckung des Steinkohlenteers im 17. Jahrhundert basiert auf durch Erfahrungswissen gepraegten Laboratoriumsexperimenten. Im Verlauf der 'Industriellen Revolution' des 18. Jahrhunderts ist der Steinkohlenteer zunaechst ein laestiges Abfallprodukt der Eisengewinnung im Kokshochofen und der Leuchtgasherstellung durch Kohlenverkokung. Erste technische Applikation finden Steinkohlenteeroele im 19. Jahrhundert durch den Eisenbahnbau zur Langzeit-Konservierung der dafuer benoetigten Holzschwellen. Die wissenschaftlichen Erfkenntnisse zur Atomtheorie, eine neue chemische Zeichensprache und die organische Elementaranalyse werden Voraussetzungen zur Entdeckung und chemischen Charakterisierung der Hauptinhaltsstoffe des Steinkohlenteers. Laboratoriumsexperimente mit den entdeckten Teerinhaltsstoffen fuehren zur Erfindung der ersten synthetischen Farbstoffe, die

  12. Shaft-retort for treating waste materials, like washery waste, bituminous shale, oil-bearing sands and the like

    Energy Technology Data Exchange (ETDEWEB)

    Koppers, H

    1916-10-29

    A shaft-retort for converting waste materials, like washery waste, bituminous shale, oil-bearing sands, brown coal and non-coking mineral coal to oil and tar by supplying heat through the shaft wall formed of an iron-sheet to the material, which is forced through a feeding member perforated for the removal of gases and vapors, and moved downward in a thin layer on the shaft wall; that is characterized by the fact that the iron heating sheet is made rotatable for the purpose of equalizing overheating of itself and the material to be treated.

  13. Inhaled smoke volume and puff indices with cigarettes of different tar and nicotine levels

    International Nuclear Information System (INIS)

    Woodman, G.; Newman, S.P.; Pavia, D.; Clarke, S.W.

    1987-01-01

    Ten asymptomatic smokers each smoked a low, low-to-middle and a middle tar cigarette with approximately the same tar-to-nicotine ratio, in a randomised order. The inhaled smoke volume was measured by tracing the smoke with the inert gas 81 Kr m . Puffing indices were recorded using an electronic smoking analyser and flowhead/cigarette holder. Throughout the study neither the mean inhaled smoke volume per puff nor the total inhaled smoke volume per cigarette changed significantly; however, the mean and total puff volumes were largest with the low tar cigarette and decreased with the higher tar brands. Puff volume was related to puff work (r s =0.83,P s =0.10,P>0.1). It is concluded that when switched between brands with the same tar-to-nicotine ratio, smokers increase their puff volumes with a lower tar cigarette but do not change the volume of smoke inhaled. Puff work and puff resistance were significantly correlated (r s =0.45,P<0.02). (author)

  14. Analysis of low-temperature tar fractions

    Energy Technology Data Exchange (ETDEWEB)

    Kikkawa, S; Yamada, F

    1952-01-01

    A preliminary comparative study was made on the applicability of the methods commonly used for the type analysis of petroleum products to the low-temperature tar fractions. The usability of chromatography was also studied.

  15. Assessment of water quality around Jaduguda uranium tailings ponds

    International Nuclear Information System (INIS)

    Mohanty, A.K.; Gurunadha Rao, V.V.S.; Ramesh, G.; Surinaidu, L.; Thama Rao, G.; Dhakate, R.; Sarangi, A.K.; Nair, R.N.

    2010-01-01

    The environmental impacts of uranium mining and milling activities are of great concern in many countries for the last three decades. These impacts range from the creation of massive stockpiles of radioactive and toxic waste rock and sand-like tailings to serious contamination of surface and groundwater with radioactive and toxic pollutants, and releases of conventional, toxic and radioactive air pollutants. Uranium mining is also associated with high concentrations of highly toxic heavy metals, which are a major source of surface and groundwater contamination. Depending upon the hydraulic properties of the fractures involved, contaminated ground water may be transported many miles from its point of origin before feeding into an aquifer. Tailings pond may contaminate the groundwater regime by continuous seepage and leaching of radionuclides and other toxic metals due to interaction of rain water through the tailings ponds. The uranium milling and tailings pond operations were started at Jaduguda since 1968. A comprehensive geological and geophysical investigation has been carried out in the Jaduguda watershed covering the tailings ponds to understand the geohydrological characteristics of the region. High resolution electrical resistivity tomography (ERT) surveys have been carried out to delineate the aquifer geometry. Water quality analyses were carried out in three seasons covering from premonsoon to postmonsoon period during 2008-2009. Uranium concentrations have been observed in the dug wells, surface water and monitoring wells

  16. Methane Fluxes and Consumption in an Oil Sands Tailings End Pit Lake

    Science.gov (United States)

    Slater, G. F.; Goad, C.; Arriaga, D.; Risacher, F.; Morris, P.; Lindsay, M. B.; Mumford, K. G.; Warren, L. A.

    2017-12-01

    End pit lakes are engineered freshwater lakes designed to reclaim land impacted by surface mining activities via establishment of a functioning ecosystem where biogeochemical cycling mitigates release of hazardous components either by stabilization or biodegradation. End pit lakes provide unique opportunities to gain insight into microbial nutrient cycling under extreme levels of impact that can be applicable to a range of levels of anthropogenic impacts and issues. This study focuses on microbial CH4 cycling in the underlying fluid fine tailings (FFT) and surface waters of Base Mine Lake (BML), the first full demonstration of end pit lake reclamation in the Athabasca Oil Sands Region (AOSR) of northern Alberta, Canada. Over two field seasons (2015 and 2016) BML was thermally stratified, turning over in spring and fall. Oxygen concentrations in the epilimnion (70 to 80 % saturation) decreased steeply through the metalimnion to 3% saturation in the hypolimnion. Conversely, CH4 concentrations were highest in the hypolimnion of BML (25 to 140 µM) with the highest values being observed at the FFT/Water interface. Concentrations decreased to 1-2 µM at the metalimnion and further decreased to < 0.5 µM in the epilimnion. CH4 δ13C in FFT porewater indicated production via fermentative pathways. FFT settlement and dewatering of 0.73 to 1.0 m/yr results in advection of an estimated 1x107 to 2x107 moles/yr CH4 into the surface water, circa an order of magnitude greater than the 3x106 moles/year estimated for molecular diffusion. Calculated fluxes of dissolved CH4 from the FFT into the hypolimnion were 4 orders of magnitude higher than those from the hypolimnion to the metalimnion, indicating a significant sink for CH4 within the hypolimnion limiting upward dissolved CH4 transport. Dissolution of CH4 from bubbles released from the FFT may be contributing to the observed epilimnion concentrations. CH4 δ13C in the hypolimnion showed only minimal enrichment with decreasing

  17. Acid Tar Lagoons: Management and Recovery

    Science.gov (United States)

    Bohers, Anna; Hroncová, Emília; Ladomerský, Juraj

    2017-04-01

    This contribution presents the issue with possibility of definitive removal of dangerous environmental burden in Slovakia - serious historical problem of two acid tar lagoons. In relation to their removal, no technology has been found so far - technologically and economically suitable, what caused problems with its management. Locality Predajná is well known in Slovakia by its character of contrasts: it is situated in the picturesque landscape of National Park buffer zone of Nízke Tatry, on the other site it is contaminated by 229 211m3 of acid tar with its characteristics of toxicity, carcinogenicity, teratogenicity, mutagenicity and toxicity especially for animals and plants. Acid tar in two landfills with depth of 1m in case of the first lagoon and 9,5m in case of the second lagoon is a waste product derived from operation of Petrochema Dubová - refinery and petrochemical plant whose activity was to process the crude oil through processes of sulfonation and adsorption technology for producing lubricating and special oils, synthetic detergents and special white oils for cosmetic and medical purposes. A part of acid tar was incinerated in two incineration plats. Concentration of SO2 in combustion gases was too high and it was not possible to decrease it under the value of 2000 mg.mn-3 [LADOMERSKÝ, J. - SAMEŠOVÁ, D.: Reduction in sulfur dioxide emissions waste gases of incineration plant. Acta facultatis ecologiae. 1999, p. 217-223]. That is why it was necessary to put them out of operation. Later, because of public opposition it was not possible to build a new incineration plat corresponding to the state of the art. Even though actual Slovak and European legislative for protection of environment against such impacts, neither of tried methods - bio or non-biologic treatment methods - was proved as suitable for processing or for recovery in the reason of different factors admission: i.e. strong aggressivity, difficulty with handling because of its sludgy and

  18. Assessment of ground-water contamination by coal-tar derivatives, St. Louis Park area, Minnesota

    Science.gov (United States)

    Hult, M.F.

    1984-01-01

    Operation of a coal-tar distillation and wood-preserving facility in St. Louis Park, Minnesota, during 1918-72 contaminated ground water with coal-tar derivatives and inorganic chemicals. Coal-tar derivatives entered the groundwater system through three major paths: (1) Spills and drippings that percolated to the water table, (2) surface runoff and plant process water that was discharged to wetlands south of the former plant site, and (3) movement of coal tar directly into bedrock aquifers through a multiaquifer well on the site.

  19. Simulation of Trajectories of Tar Ball Transport to the Goa Coast

    Digital Repository Service at National Institute of Oceanography (India)

    Suneel, V.; Vethamony, P.; VinodKumar, K.; Babu, M.T.; Prasad, V.S.R.

    Arrival of tar balls to the Goa coast during pre- and southwest monsoon seasons has been a regular phenomenon in the past few years. In one such event, we observed tar ball deposits along the Goa coast during August 2010, April 2011 and May 2011...

  20. The Legend of Hot Tar or Pitch as a Defensive Weapon

    DEFF Research Database (Denmark)

    Atzbach, Rainer

    2015-01-01

    research. In reality, this way of fighting can only be seen as a legend, i.e. a story with only a relative truth at its core. This paper will examine the origin of this historical tradition and its archaeological and architectural sources. The chemical and physical properties of tar pitch and its...... production and use during the Middle Ages will be discussed with special focus on the application of tar pitch as an ingredient in medieval and post-medieval thermal weapons (especially Greek Fire, the firebomb and the fire arrow). The punishment of tarring and feathering will also be considered...

  1. Ensamblajes urbanos: la TAR y el examen de la ciudad

    Directory of Open Access Journals (Sweden)

    Ignacio Farías

    2011-03-01

    Full Text Available Este artículo presenta nuevas perspectivas de investigación y desafíos analíticos que la teoría del actor-red (TAR abre para los estudios urbanos. En primer lugar, se revisan cómo los principios de relacionalidad híbrida y asociatividad plana de la TAR están siendo adoptados en los estudios urbanos para ampliar simétricamente la ecología urbana a no-humanos e impugnar concepciones escalares del espacio y economías urbanas. A continuación, se propone que la TAR trae consigo un desafío más fundamental relativo a la concepción de la ciudad como objeto de estudio. Mientras su comprensión habitual como objeto espacial, entidad político-económica y/o forma sociocultural subraya su carácter singular, estable y delimitado, la TAR permite pensar la ciudad como un objeto múltiple y decentrado. La noción de ensamblajes urbanos se introduce entonces para dar cuenta de la circulación y devenir de la ciudad en múltiples redes híbridas y translocales. El artículo concluye sopesando algunas de las consecuencias de este exámen de la ciudad, especialmente el reposicionamiento del problema de la complejidad, urbana en este caso, como punto, si no de partida, entonces al menos de llegada para la TAR.

  2. Copyrolysis of coal with coke-oven gas. III. Analysis of tar

    Energy Technology Data Exchange (ETDEWEB)

    Liao, H.; Sun, C.; Li, B.; Liu, Z. [Chinese Academy of Sciences, Taiyuan (China). State Key Laboratory of Coal Conversion, Institute of Coal Chemistry

    1998-02-01

    Tars from copyrolysis of Xianfeng lignite with coke-oven gas (COG) at different pressures (0.1-5 MPa) and heating rates (5-25{degree}C/min) to a final temperature of 650{degree}C were analyzed and compared with hydropyrolysis under the same H{sub 2} partial pressure. The results indicated that high contents of BTX, PCX and naphthalene were found in the tar from copyrolysis of Xianfeng lignite with COG. Pressure and heating rate have important effects on tar yields and the contents of BTX, PCX and naphthalene in oil. Increasing pressure and decreasing heating rate enhance the tar yields and result in high yields of BTX and PCX. When compared with hydropyrolysis under the same H{sub 2} partial pressure, the tar yield increases by 1.2 times and the yields of BTX, PCX and naphthalene by about 1.6, 1.3 and 1.6 times, respectively. At the same total pressure (3MPa), the yields of BTX and naphthalene from copyrolysis are equal to those from hydropyrolysis. The results reveal that other components in COG, such as methane, carbon monoxide etc., are of importance for pyrolysis behaviour of coal under COG and improvement of oil qualities. 5 refs., 5 figs., 2 tabs.

  3. The distribution and migration of sodium from a reclaimed upland to a constructed fen peatland in a post-mined oil sands landscape.

    Science.gov (United States)

    Kessel, Eric D; Ketcheson, Scott J; Price, Jonathan S

    2018-07-15

    Post-mine landscape reclamation of the Athabasca Oil Sands Region requires the use of tailings sand, an abundant mine-waste material that often contains large amounts of sodium (Na + ). Due to the mobility of Na + in groundwater and its effects on vegetation, water quality is a concern when incorporating mine waste materials, especially when attempting to construct groundwater-fed peatlands. This research is the first published account of Na + redistribution in groundwater from a constructed tailings sand upland to an adjacent constructed fen peat deposit (Nikanotee Fen). A permeable petroleum coke layer underlying the fen, extending partway into the upland, was important in directing flow and Na + beneath the peat, as designed. Initially, Na + concentration was highest in the tailings sand (average of 232mgL -1 ) and lowest in fen peat (96mgL -1 ). Precipitation-driven recharge to the upland controlled the mass flux of Na from upland to fen, which ranged from 2 to 13tons Na + per year. The mass flux was highest in the driest summer, in part from dry-period flowpaths that direct groundwater with higher concentrations of Na + into the coke layer, and in part because of the high evapotranspiration loss from the fen in dry periods, which induces upward water flow. With the estimated flux rates of 336mmyr -1 , the Na + arrival time to the fen surface was estimated to be between 4 and 11years. Over the four-year study, average Na + concentrations within the fen rooting zone increased from 87 to 200mgL -1 , and in the tailings sand decreased to 196mgL -1 . The planting of more salt-tolerant vegetation in the fen is recommended, given the potential for Na + accumulation. This study shows reclamation designs can use layered flow system to control the rate, pattern, and timing of solute interactions with surface soil systems. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

  4. Relevance of carbon structure to formation of tar and liquid alkane during coal pyrolysis

    International Nuclear Information System (INIS)

    Liu, Peng; Le, Jiawei; Wang, Lanlan; Pan, Tieying; Lu, Xilan; Zhang, Dexiang

    2016-01-01

    Highlights: • Curve-fitting method was used to quantify the accurate contents of structural carbon. • Effect of carbon structure in coal with different rank on formation of pyrolysis tar was studied. • Numerical interrelation between carbon types in coal structure and tar yield is elaborated. • Effect of carbon structure on formation of liquid alkane during coal pyrolysis is discussed. - Abstract: The relevance of carbon structure to formation of tar and liquid alkane during coal pyrolysis were discussed extensively. The pyrolysis tests were carried out in a tube reactor at 873 K and keep 15 min. The carbon distribution in coals was investigated by solid state "1"3C nuclear magnetic resonance (N.M.R.). The curve-fitting method was used to quantify the accurate contents of structural carbon. The alkanes in coal tar were analyzed by Gas Chromatograph–Mass Spectrometer (GC–MS). The results show that oxygen-linked aromatic carbon decreases with the increasing of coal rank. The aliphatic carbon contents of Huainan (HN) coal are 44.20%, the highest among the four coals. The carbon types in coal structure have a significant influence on the formation of tar and liquid alkane. The coal tar yields are related to the aliphatic substituted aromatic carbon, CH_2/CH_3 ratio and oxygen-linked carbon in coal so that the increasing order of tar yield is Inner Mongolia lignite (IM, 6.30 wt.%) < Sinkiang coal (SK, 7.55 wt.%) < Shenmu coal (SM, 12.84 wt.%) < HN (16.29 wt.%). The highest contents of oxygen-linked aromatic carbon in IM lead to phenolic compound of 41.06% in IM-tar. The contents of alkane in SM-tar are the highest because the appropriate CH_2/CH_3 ratio and the highest aliphatic side chains on aromatic rings in SM leading to generate aliphatic hydrocarbon with medium molecular weight easily. The mechanism on formation of tar and liquid alkane plays an important role in guiding the industrialization of pyrolysis-based poly-generation producing tar with high

  5. Identification of sources of tar balls deposited along the Goa coast, India, using fingerprinting techniques

    International Nuclear Information System (INIS)

    Suneel, V.; Vethamony, P.; Zakaria, M.P.; Naik, B.G.; Prasad, K.V.S.R.

    2013-01-01

    Highlights: ► This is first fingerprinting study in India on identification of source of tar balls. ► Tar balls were formed from tanker-wash spills and they resemble floating tar ball. ► δ 13 C values of Bombay High crude oil and the present tar balls do not match. ► Compound specific stable carbon isotope analysis confirmed the source of tar balls. ► Source is confirmed as the South East Asian Crude Oil and not the Bombay High crude. -- Abstract: Deposition of tar balls along the coast of Goa, India is a common phenomenon during the southwest monsoon. Representative tar ball samples collected from various beaches of Goa and one Bombay High (BH) crude oil sample were subjected to fingerprint analysis based on diagnostic ratios of n-alkane, biomarkers of pentacyclic tri-terpanes and compound specific stable carbon isotope (δ 13 C) analysis to confirm the source. The results were compared with the published data of Middle East Crude Oil (MECO) and South East Asian Crude Oil (SEACO). The results revealed that the tar balls were from tanker-wash derived spills. The study also confirmed that the source is not the BH, but SEACO. The present study suggests that the biomarkers of alkanes and hopanes coupled with stable carbon isotope analysis act as a powerful tool for tracing the source of tar balls, particularly when the source specific biomarkers fail to distinguish the source

  6. 29 CFR 1926.1102 - Coal tar pitch volatiles; interpretation of term.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Coal tar pitch volatiles; interpretation of term. 1926.1102 Section 1926.1102 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... Hazardous Substances § 1926.1102 Coal tar pitch volatiles; interpretation of term. Note: The requirements...

  7. A review of the primary measures for tar elimination in biomass gasification processes

    International Nuclear Information System (INIS)

    Devi, Lopamudra; Ptasinski, K.J.; Janssen, F.J.J.G.

    2003-01-01

    Tar formation is one of the major problems to deal with during biomass gasification. Tar condenses at reduced temperature, thus blocking and fouling process equipments such as engines and turbines. Considerable efforts have been directed on tar removal from fuel gas. Tar removal technologies can broadly be divided into two approaches; hot gas cleaning after the gasifier (secondary methods), and treatments inside the gasifier (primary methods). Although secondary methods are proven to be effective, treatments inside the gasifier are gaining much attention as these may eliminate the need for downstream cleanup. In primary treatment, the gasifier is optimized to produce a fuel gas with minimum tar concentration. The different approaches of primary treatment are (a) proper selection of operating parameters, (b) use of bed additive/catalyst, and (c) gasifier modifications. The operating parameters such as temperature, gasifying agent, equivalence ratio, residence time, etc. play an important role in formation and decomposition of tar. There is a potential of using some active bed additives such as dolomite, olivine, char, etc. inside the gasifier. Ni-based catalyst are reported to be very effective not only for tar reduction, but also for decreasing the amount of nitrogenous compounds such as ammonia. Also, reactor modification can improve the quality of the product gas. The concepts of two-stage gasification and secondary air injection in the gasifier are of prime importance. Some aspects of primary methods and the research and development in this area are reviewed and cited in the present paper

  8. Presentations of the CONRAD Research Symposium : oil sands water usage workshop

    International Nuclear Information System (INIS)

    2004-01-01

    This symposium provided a forum to exchange ideas regarding water use by the oil sands industry in Canada. The topics of discussion addressed timely issues such as corrosion control in pipelines, cumulative discharge modelling in the oil sands area, waste management schemes, the effects of potential limits on water withdrawal for thermal recovery operations and plant operations, the feasibility of geological sequestration of salts, and the impact of process-affected water on bitumen recovery. Other topics of discussion included tailings ponds management, deoxygenation of water, nanofiltration for water management, water quality for wetlands, water reuse, and water supply security. The conference featured 25 presentations, of which 17 have been indexed separately for inclusion in this database. tabs., figs

  9. Solid state 13 C NMR quantitative study of wood tar pitches

    International Nuclear Information System (INIS)

    Prauchner, Marcos Juliano; Pasa, Vanya Marcia Duarte; Menezes, Sonia Maria Cabral de

    1999-01-01

    In this work, solid-state 13 C NMR is used with other techniques to characterize Eucalyptus tar pitches and to follow their polymerization reactions. The pitches are the residues of distillation (about 50% m;m) of the tar generated in Eucalyptus slow pyrolysis for charcoal production in metal industry

  10. 29 CFR 1915.1002 - Coal tar pitch volatiles; interpretation of term.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Coal tar pitch volatiles; interpretation of term. 1915.1002 Section 1915.1002 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH... Toxic and Hazardous Substances § 1915.1002 Coal tar pitch volatiles; interpretation of term. Note: The...

  11. Sources of atmospheric emissions in the Athabasca oil sands region

    International Nuclear Information System (INIS)

    1996-01-01

    An inventory of emissions for the Athabasca oil sands airshed that can be used as a basis for air quality assessments was presented. This report was prepared for the Suncor Steepbank Mine Environmental Impact Assessment (EIA) and for the Syncrude Aurora Mine EIA. Both Syncrude and Suncor have plans to develop new oil sands leases and to increase their crude oil and bitumen production. Suncor has proposed modifications to reduce SO 2 emissions to the atmosphere and Syncrude will develop additional ambient air quality, sulphur deposition and biomonitoring programs to ensure that environmental quality is not compromised because of atmospheric emissions associated with their operations. Major emission sources are controlled and monitored by regulatory statutes, regulations and guidelines. In this report, the following four types of emission sources were identified and quantified: (1) major industrial sources associated with Suncor's and Syncrude's current oil sands operations, (2) fugitive and area emission sources such as volatilization of hydrocarbons from tanks and tailings ponds, (3) other industrial emission sources in the area, including oil sands and non-oil sands related facilities, and (4) highway and residential emission sources. Emissions associated with mining operations include: SO 2 , NO x , CO, and CO 2 . The overall conclusion was that although there are other smaller sources of emissions that can influence air quality, there is no reason to doubt that Suncor and Syncrude oil sands operations are the major sources of emissions to the atmosphere. 13 refs., 12 tabs., 8 figs

  12. Avoiding tar formation in biocoke production from waste biomass

    International Nuclear Information System (INIS)

    Adrados, A.; De Marco, I.; Lopez-Urionabarrenechea, A.; Solar, J.; Caballero, B.

    2015-01-01

    This paper focuses in avoiding tar formation and in optimizing pyrolysis gas (maximizing H 2 and CO) in the production of biocoke from waste lignocellulosic biomass. In order to obtain metallurgical grade biochar (biocoke) slow heating rate and high temperature are required. Under such conditions useless pyrolysis liquids, mainly composed of water together with some heavy-sticky tars, are obtained. In order to make biocoke a cost-effective process it is necessary to optimize pyrolysis vapors avoiding tar formation and maximizing the amount and quality of both coke and gases. With this objective, in this work different heating rates (3–20 °C min −1 ) and catalysts (zeolite, Ni/CeO 2 –Al 2 O 3 ) have been tested in a two step pyrolysis process. Olive tree cuttings have been pyrolyzed in a 3.5 L batch reactor at 750 °C and the vapors generated have been thermally and catalytically treated at 900 °C in a second tubular reactor. About 25 wt.% biocoke useful as reducing agent in certain metallurgical processes, ≈57 wt.% gases with near 50 vol.% H 2 , and no tar production has been achieved when a heating rate of 3 °C min −1 and the homemade Ni/CeO 2 –Al 2 O 3 catalyst were used. - Highlights: • Metallurgical grade biochar was obtained by olive waste pyrolysis. • Low heating rates avoid tar formation and increase gas and biochar yields. • Ni/CeO 2 –Al 2 O 3 was better than HZSM5 zeolite for vapor upgrading in a second step. • Ni/CeO 2 –Al 2 O 3 and 3 °C min −1 gave the maximum H 2 , gas and biochar yields

  13. Laboratory research on tailings stabilization methods and their effectiveness in radiation containment

    International Nuclear Information System (INIS)

    Macbeth, P.J.; Jensen, C.M.; Rogers, V.C.; Overmyer, R.F.

    1978-04-01

    This report describes a study of various methods, techniques, and materials for stabilizing uranium mill tailings to reduce radon exhalation. Radon emanation from tailings particles, radon exhalation from tailings, and methods that could be used to reduce radon exhalation from tailings piles are discussed. Surface radon flux and soil gas concentrations were measured in experiment chambers or columns consisting of uranium tailings and various types and thicknesses of cover materials. The applicability of diffusion theory was examined and effective diffusion coefficients were determined for clay, soil, and sand. The variation of radon flux with atmospheric effects and moisture also was investigated. The effectiveness of several types of chemical stabilizers for both volumetric and surface application in reducing radon exhalation is reported. Some volumetric stabilizers reduced radon flux by 90 percent or more. Radon flux was determined through the use of charcoal gas mask canisters, and flux accumulation chambers sampled by Lucas cells. Both of these techniques are described. Soil gas concentration was sampled with Lucas cells and counted with a sodium iodide scintillation spectrometer system. Emanating power of uranium tailings was measured for several particle sizes and found to be relatively constant at about 20 percent. Two types of grasses were found that would grow in tailings if sufficient water and fertilizer were provided. The effect of vegetation on radon exhalation was not determined

  14. Cancer risk estimation for mixtures of coal tars and benzo(a)pyrene

    International Nuclear Information System (INIS)

    Gaylor, D.W.; Culp, S.J.; Goldstein, L.S.; Beland, F.A.

    2000-01-01

    Two-year chronic bioassays were conducted by using B6C3F1 female mice fed several concentrations of two different mixtures of coal tars from manufactured gas waste sites or benzo(a)pyrene (BaP). The purpose of the study was to obtain estimates of cancer potency of coal tar mixtures, by using conventional regulatory methods, for use in manufactured gas waste site remediation. A secondary purpose was to investigate the validity of using the concentration of a single potent carcinogen, in this case benzo(a)pyrene, to estimate the relative risk for a coal tar mixture. The study has shown that BaP dominates the cancer risk when its concentration is greater than 6,300 ppm in the coal tar mixture. In this case the most sensitive tissue site is the forestomach. Using low-dose linear extrapolation, the lifetime cancer risk for humans is estimated to be: Risk -4 (ppm coal tar in total diet) + 240 x 10 -4 (ppm BaP in total diet), based on forestomach tumors. If the BaP concentration in the coal tar mixture is less than 6,300 ppm, the more likely case, then lung tumors provide the largest estimated upper limit of risk, Risk -4 (ppm coal tar in total diet), with no contribution of BaP to lung tumors. The upper limit of the cancer potency (slope factor) for lifetime oral exposure to benzo(a)pyrene is 1.2 x 10 -3 per microg per kg body weight per day from this Good Laboratory Practice (GLP) study compared with the current value of 7.3 x 10 -3 per microg per kg body weight per day listed in the US EPA Integrated Risk Information System

  15. Experimental and theoretical evaluation of the performance of a tar solar water heater

    International Nuclear Information System (INIS)

    Ammari, H.D.; Nimir, Y.L.

    2003-01-01

    The paper presents an experimental and theoretical evaluation of the performance of a tar solar water heater and comparison with that of a conventional type collector. The performance of both collectors is assessed under the same conditions. Both of the collectors have the same surface area and are glazed. The conventional type has the water tubes welded to the absorber plate, whereas in the tar type, the tar acts as an absorber plate that covers the water tubes. The theoretical model for each collector type, with the transient effects taken into account, is based on a control volume and a time base in the related energy equations. By considering a small element of the collector in each case, three partial differential equations were developed for each collector and were solved numerically by the Runge-Kutta method of the fifth order. A good agreement was achieved between the numerical and experimental results for both the conventional and tar collectors, indicating the feasibility of employing the theoretical model in the design of flat plate solar collectors. The results also showed that the conventional collector is more efficient than the tar type during most of the daylight, but the tar collector had the added advantage of better conservation of energy in late afternoon and evening

  16. Estimating release of polycyclic aromatic hydrocarbons from coal tar at manufactured-gas plant sites

    International Nuclear Information System (INIS)

    Loehr, R.C.; Rao, P.S.C.; Lee, L.S.; Okuda, I.

    1992-08-01

    One component of the EPRI's research on Envirorunental Behavior of Organic Substances (EBOS) consists of developing information and models to predict releases of monocyclic and polycyclic aromatic hydrocarbons (MAHs and PAHs) to groundwater from coal tars and contaminated soils at MGP sites. The results of this report focus primarily on release of PAHs from coal tars. There are at least two approaches to predicting the release of organic chemicals from coal tar to water. The simplest method to estimate aqueous concentrations is to assume that water solubility of a PAH compound released from the tar can be defined by equilibrium precipitation-dissolution reactions. Application of Raoult's law is another method to predict aqueous concentrations, which requires the assumption of ''ideal'' behavior for partitioning of PAHs between the tar and water phases. To evaluate the applicability of these two methods for predicting PAH releases, laboratory experiments were conducted with eight coal tar samples from former MGP sites across the country. Migration of chemicals in the environment and resulting contaminant plumes in groundwater are determined by leachate concentrations of the chemicals. The use of equilibrium precipitation-dissolution reactions will usually result in an overestimation of PAH concentrations in the leachate from a coal tar source, and thus the resulting PAH concentrations in groundwater. Raoult's law appears to be a more accurate approach to predicting the release of several PAHs from coal tars. Furthermore, if nonequilibrium conditions prevail, aqueous-phase PAH concentrations will be even lower than those predicted using Raoult's law

  17. Release of polyaromatic hydrocarbons from coal tar contaminated soils

    International Nuclear Information System (INIS)

    Priddy, N.D.; Lee, L.S.

    1996-01-01

    A variety of process wastes generated from manufactured gas production (MGP) have contaminated soils and groundwater at production and disposal sites. Coal tar, consisting of a complex mixture of hydrocarbons present as a nonaqueous phase liquid, makes up a large portion of MGP wastes. Of the compounds in coal tar, polyaromatic hydrocarbons (PAHs) are the major constituents of environmental concern due to their potential mutagenic and carcinogenic hazards. Characterization of the release of PAHs from the waste-soil matrix is essential to quantifying long-term environmental impacts in soils and groundwater. Currently, conservative estimates for the release of PAHs to the groundwater are made assuming equilibrium conditions and using relationships derived from artificially contaminated soils. Preliminary work suggests that aged coal tar contaminated soils have much lower rates of desorption and a greater affinity for retaining organic contaminants. To obtain better estimates of desorption rates, the release of PAHs from a coal tar soil was investigated using a flow-interruption, miscible displacement technique. Methanol/water solutions were employed to enhance PAH concentrations above limits of detection. For each methanol/water solution employed, a series of flow interrupts of varying times was invoked. Release rates from each methanol/water solution were estimated from the increase in concentration with duration of flow interruption. Aqueous-phase release rates were then estimated by extrapolation using a log-linear cosolvency model

  18. Diffusion coefficients of radon in candidate soils for covering uranium mill tailings

    International Nuclear Information System (INIS)

    Kalkwarf, D.R.; Silker, W.B.

    1983-10-01

    Diffusion coefficients were measured for radon in 34 soils that had been identified by uranium mill personnel as candidate soils for covering their tailings piles in order to reduce radon emission. The coefficients referred to diffusion in the total pore space of the soils. They were measured by a steady-state method using soil columns compacted to greater than 80% of their Proctor maximum packing densities, but with moisture contents generally less than would be expected at a tailings site. Three published empirical equations relating diffusion coefficients to soil moisture and porosity were tested with these data. The best fir was obtained with the equation: D = 0.70 exp [-4(m-mP 2 +m 5 )] in which P is the dry porosity of the soil and m is its moisture saturation, i.e. the fraction of pore volume filled with water. This equation was used to extrapolate measured coefficients to values expected at soil-moisture contents representative of tailings sites in the western United States. Extrapolated values for silty sands and clayey sands range from 0.004 to 0.06 cm 2 /s where w, the weight ratio of water to dry soil, is expected to vary from 0.04 to 0.09. Values for inorganic silts and clays ranged from 0.001 to 0.02 cm 2 /s where w is expected to vary from 0.10 to 0.13. 8 references, 1 figure, 1 table

  19. Extraction of tar acids with methanol from low-temperature tar

    Energy Technology Data Exchange (ETDEWEB)

    Funasaka, W; Yokogawa, C; Suga, S

    1948-01-01

    From 20 grams crude middle oil, boiling at 200/sup 0/ to 250/sup 0/, acid content 40%, tar acids were extracted at 20/sup 0/ to 30/sup 0/ with MeOH for comparison with EtOH, NMe/sub 3/, and ethylene glycol. When 80% MeOH is used, the oil extracted amounts to 61%, including 9% acids, if the ratio of crude oil and solvent is kept at 1:2. EtOH is inferior to MeOH. The properties of the crude oil and the purified oil extracted with 80% MeOH are described.

  20. Tar Removal from Biomass Producer Gas by Using Biochar

    DEFF Research Database (Denmark)

    Ravenni, Giulia; Henriksen, Ulrik Birk; Ahrenfeldt, Jesper

    2017-01-01

    The biomass-derived char (biochar) produced in the gasifier as a residue, is a potential solution for removing tars from producer gas. This work investigates the interaction between tar compounds and biochar. Residual biochar from a TwoStage gasifier was tested as bed material in a laboratory setup....... Phenol and naphthalene were chosen as model tars, and entrained in a nitrogen flow. The gaseous stream was sampled before and after the biochar bed to evaluate the extent of conversion. The biochar bed (30g) was tested at 250°C, 500°C and 600°C, with for 3 consecutive hours. The compounds concentration...... in the gas phase was quantified by stable isotope dilution analysis, using Gas Chromatography-Mass Spectrometry (GC-MS). Results showed a significant effect of biochar on the removal of phenol, at all temperatures. Naphthalene was removed less efficiently at higher temperature, and this trend was even more...

  1. Solvent refining of low-temperature tar with liquid ammonia

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, K

    1953-01-01

    The middle fractions of low-temperature tar were treated with mixed solutions of H/sub 2/O and liquid NH/sub 3/ at 0/sup 0/ and 20/sup 0/, and with liquid NH/sub 3/ at -10, 0, + 10, and 20/sup 0/, and phase equilibrium between tar acids, neutral oil, and solvents were studied. The distribution ratio ranged from less than 1 to greater than 1 when the solvent contained about 20 percent (by weight) H/sub 2/O. When the solvent contained less than 85 percent (by weight) NH/sub 3/, the yield of extract was small but the purity of phenols in the extracted oil was above 90 percent. Solvent containing about 85 percent NH/sub 3/ (by weight) is considered optimum for separating tar acids from oils. A novel definition is proposed for solvent selectivity as the difference between the concentration of the solute in the extract layer, on a solvent-free basis, and the concentration in the raffinate layer.

  2. The gravel sand transition in a disturbed catchment

    Science.gov (United States)

    Knighton, A. David

    1999-03-01

    More than 40 million cubic metres of mining waste were supplied to the Ringarooma River between 1875 and 1984, leading to successive phases of aggradation and degradation. The natural bed material is gravel but, given the volume of introduced load and the fact that much of the input was less than 5 mm in diameter, the size composition of the bed changed from gravel to sand during the phase of downstream progressive aggradation. A very sharp gravel-sand transition developed in which median grain size decreased from over 30 mm to under 3 mm in less than 500 m. With upstream supplies of mining debris becoming depleted first, degradation followed the same downstream progressive pattern as aggradation, causing the transition to migrate downstream. By 1984, the river could be regarded as a series of zones, each characterized by a particular bed condition: a natural cobble-gravel bed, unaffected by mining inputs (0-32 km); pre-disturbance bed re-exposed by degradation over 35-40 years (32-53 km); sandy substrate with a gravel armour produced by differential transport during degradation (53-65 km); sand dominated but with developing surface patches of coarser material (65-75 km); sandy bed reflecting the size composition of the original mining input (75-118 km). Although the gravel-sand transition itself is sharp, the transitional zone is lengthy (53-75 km). As degradation continues, the gravel-sand transition is expected to progress downstream but it has remained in a stable position for 12 years. Indeed, two major floods during the period released large quantities of sand from the sub-armour layer and newly-formed banks of mine tailings, causing fining both above and below the transition. Surface grain size is an adjustable component in the transitional zone as the river strives to recover from a major anthropogenic disturbance.

  3. Ukrainian brown-coal tars recovered at low-temperature carbonization with solid heating medium

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, V I; Govorova, R P; Fadeicheva, A G; Kigel, T B; Chernykh, M K

    1955-01-01

    Three samples of tar were recovered in the laboratory from brown coals carbonized at 375/sup 0/ to 456/sup 0/ +- 25/sup 0/ in a retort with inner heating by solid circulating medium, namely, semicoke (ratio: 4 or 3:1) first heated to 700/sup 0/. One comparative (parallel) experiment was carried out in a retort with inner heating by inert gases entering the retort at 580/sup 0/ to 600/sup 0/ and leaving it at 115/sup 0/ to 120/sup 0/. The tars that were recovered from the retort with the solid heating medium contained a high percentage of coal dust and moisture, which were separated from the tars in supercentrifuges (15,000 rpm). Four samples of cleaned tars were fractionated in a Cu flask with a 2-ball fractional column. The tars from the retort with the solid-heating medium are characterized by increased yield of the petroleum-ether fraction (16.3 or 19.3%) and decreased yield of the paraffin fraction (15.1 to 21.2%) in comparison with those of tar from the retort with gas heating (5.9% of the petroleum ether fraction and 36.5% of paraffin fraction). The yield of paraffin from the paraffin fraction also decreased from 90.6% to 62.6-74.3%. This result shows that in the first case the carbonized products were cracked to a higher degree than those from the retort with gas heating. In raw phenols recovered from fractions of investigated tars, the yield of the phenol-cresol fraction (182/sup 0/ to 204/sup 0/) decreased from 25.9% to 13.0-18.9%.

  4. Catalytic decomposition of tar derived from wood waste pyrolysis using Indonesian low grade iron ore as catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Wicakso, Doni Rahmat [Chemical Engineering Department, Faculty of Engineering, Lambung Mangkurat University, Jalan A. Yani KM. 36 Banjarbaru, 70714, South Kalimantan (Indonesia); Chemical Engineering Department, Faculty of Engineering, Gadjah Mada University, Jalan Grafika No. 2 Bulaksumur, Yogyakarta, 55281 (Indonesia); Sutijan; Rochmadi [Chemical Engineering Department, Faculty of Engineering, Gadjah Mada University, Jalan Grafika No. 2 Bulaksumur, Yogyakarta, 55281 (Indonesia); Budiman, Arief, E-mail: abudiman@ugm.ac.id [Chemical Engineering Department, Faculty of Engineering, Gadjah Mada University, Jalan Grafika No. 2 Bulaksumur, Yogyakarta, 55281 (Indonesia); Center for Energy Studies, Gadjah Mada University, Sekip K1A, Yogyakarta, 55281 (Indonesia)

    2016-06-03

    Low grade iron ore can be used as an alternative catalyst for bio-tar decomposition. Compared to other catalysts, such as Ni, Rd, Ru, Pd and Pt, iron ore is cheaper. The objective of this research was to investigate the effect of using low grade iron ore as catalyst for tar catalytic decomposition in fixed bed reactor. Tar used in this experiment was pyrolysis product of wood waste while the catalyst was Indonesian low grade iron ore. The variables studied were temperatures between 500 – 600 °C and catalyst weight between 0 – 40 gram. The first step, tar was evaporated at 450 °C to produce tar vapor. Then, tar vapor was flowed to fixed bed reactor filled low grade iron ore. Gas and tar vapor from reactor was cooled, then the liquid and uncondensable gas were analyzed by GC/MS. The catalyst, after experiment, was weighed to calculate total carbon deposited into catalyst pores. The results showed that the tar components that were heavy and light hydrocarbon were decomposed and cracked within the iron ore pores to from gases, light hydrocarbon (bio-oil) and carbon, thus decreasing content tar in bio-oil and increasing the total gas product. In conclusion, the more low grade iron ore used as catalyst, the tar content in the liquid decrease, the H{sup 2} productivity increased and calorimetric value of bio-oil increased.

  5. Influence green sand system by core sand additions

    Directory of Open Access Journals (Sweden)

    N. Špirutová

    2012-01-01

    Full Text Available Today, about two thirds of iron alloys casting (especially for graphitizing alloys of iron are produced into green sand systems with usually organically bonded cores. Separation of core sands from the green sand mixture is very difficult, after pouring. The core sand concentration increase due to circulation of green sand mixture in a closed circulation system. Furthermore in some foundries, core sands have been adding to green sand systems as a replacement for new sands. The goal of this contribution is: “How the green sand systems are influenced by core sands?”This effect is considered by determination of selected technological properties and degree of green sand system re-bonding. From the studies, which have been published yet, there is not consistent opinion on influence of core sand dilution on green sand system properties. In order to simulation of the effect of core sands on the technological properties of green sands, there were applied the most common used technologies of cores production, which are based on bonding with phenolic resin. Core sand concentration added to green sand system, was up to 50 %. Influence of core sand dilution on basic properties of green sand systems was determined by evaluation of basic industrial properties: moisture, green compression strength and splitting strength, wet tensile strength, mixture stability against staling and physical-chemistry properties (pH, conductivity, and loss of ignition. Ratio of active betonite by Methylene blue test was also determined.

  6. Phytotoxicity and Plant Productivity Analysis of Tar-Enriched Biochars

    Science.gov (United States)

    Keller, M. L.; Masiello, C. A.; Dugan, B.; Rudgers, J. A.; Capareda, S. C.

    2008-12-01

    Biochar is one of the three by-products obtained by the pyrolysis of organic material, the other two being syngas and bio-oil. The pyrolysis of biomass has generated a great amount of interest in recent years as all three by-products can be put toward beneficial uses. As part of a larger project designed to evaluate the hydrologic impact of biochar soil amendment, we generated a biochar through fast pyrolysis (less than 2 minutes) of sorghum stock at 600°C. In the initial biochar production run, the char bin was not purged with nitrogen. This inadvertent change in pyrolysis conditions produced a fast-pyrolysis biochar enriched with tars. We chose not to discard this batch, however, and instead used it to test the impact of tar-enriched biochars on plants. A suite of phytotoxicity tests were run to assess the effects of tar-rich biochar on plant germination and plant productivity. We designed the experiment to test for negative effects, using an organic carbon and nutrient-rich, greenhouse- optimized potting medium instead of soil. We used Black Seeded Simpson lettuce (Lactuca sativa) as the test organism. We found that even when tars are present within biochar, biochar amendment up to 10% by weight caused increased lettuce germination rates and increased biomass productivity. In this presentation, we will report the statistical significance of our germination and biomass data, as well as present preliminary data on how biochar amendment affects soil hydrologic properties.

  7. Carbon materials for syngas conditioning and tar removal

    International Nuclear Information System (INIS)

    Romero Millán, Lina María; Sierra Vargas, Fabio Emiro

    2017-01-01

    Within the framework of worldwide energy context, the development of technologies and processes for energy production form renewable and non-conventional sources is a priority. According to this, gasification is an interesting process that converts different kinds of organic materials in fuel gases. The main issue related with this process is the fact that the producer gas contains also contaminants and tars that are undesirable for the gas usage in internal combustion motors or turbines. The present work aims to analyze the actual state of the existing methods to remove tars form gasification fuel gases, emphasizing the use of different kinds of carbon materials. (author)

  8. Process from removing benzine, toluene, etc. , from petroleum residues, coal tar, and shale tar, etc

    Energy Technology Data Exchange (ETDEWEB)

    Hlawaty, F

    1888-08-11

    A process is described for the preparation of ligroin and its homologs as well as naphthalene and anthracene consisting in leading superheated water vapor into a mixture of petroleum residues (or mineral coal tar, etc.) heated to about 400/sup 0/C with cellulosic substances as sage shreds, sea grass, or straw, with addition of caustic alkali.

  9. Carbazole is a naturally occurring inhibitor of angiogenesis and inflammation isolated from antipsoriatic coal tar

    Energy Technology Data Exchange (ETDEWEB)

    Jack L. Arbiser; Baskaran Govindarajan; Traci E. Battle; Rebecca Lynch; David A. Frank; Masuko Ushio-Fukai; Betsy N. Perry; David F. Stern; G. Tim Bowden; Anquan Liu; Eva Klein; Pawel J. Kolodziejski; N. Tony Eissa; Chowdhury F. Hossain; Dale G. Nagle [Emory University School of Medicine, Atlanta, GA (United States). Department of Dermatology

    2006-06-15

    Coal tar is one of the oldest and an effective treatment for psoriasis. Coal tar has been directly applied to the skin, or used in combination with UV light as part of the Goeckerman treatment. The use of coal tar has caused long-term remissions in psoriasis, but has fallen out of favor because the treatment requires hospitalization and coal tar is poorly acceptable aesthetically to patients. Thus, determining the active antipsoriatic component of coal tar is of considerable therapeutic interest. We fractionated coal tar into its components, and tested them using the SVR angiogenesis inhibitor assay. Treatment of SVR endothelial cells with coal tar fractions resulted in the isolation of a single fraction with antiangiogenic activity. The active antiangiogenic compound in coal tar is carbazole. In addition to antiangiogenic activity, carbazole inhibited the production of inflammatory IL-15 by human mononuclear cells. IL-15 is elevated in psoriasis and is thought to contribute to psoriatic inflammation. Carbazole treatment also reduced activity of inducible nitric oxide synthase (iNOS), which is proinflammatory and elevated in psoriasis. The effect of carbazole on upstream pathways in human psoriasis was determined, and carbazole was shown to inhibit signal transducer and activator of transcription (stat)3-mediated transcription, which has been shown to be relevant in human psoriasis. IL-15, iNOS, and stat3 activation require the activation of the small GTPase rac for optimal activity. Carbazole was found to inhibit rac activation as a mechanism for its inhibition of downstream inflammatory and angiogenic pathways. Given its antiangiogenic and anti-inflammatory activities, carbazole is likely a major component of the antipsoriatic activity of coal tar. Carbazole and derivatives may be useful in the therapy of human psoriasis.

  10. Comprehensive database of Manufactured Gas Plant tars. Part C. Heterocyclic and hydroxylated polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Gallacher, Christopher; Thomas, Russell; Lord, Richard; Kalin, Robert M; Taylor, Chris

    2017-08-15

    Coal tars are a mixture of organic and inorganic compounds that were by-products from the manufactured gas and coke making industries. The tar compositions varied depending on many factors such as the temperature of production and the type of retort used. For this reason a comprehensive database of the compounds found in different tar types is of value to understand both how their compositions differ and what potential chemical hazards are present. This study focuses on the heterocyclic and hydroxylated compounds present in a database produced from 16 different tars from five different production processes. Samples of coal tar were extracted using accelerated solvent extraction (ASE) and derivatized post-extraction using N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) with 1% trimethylchlorosilane (TMCS). The derivatized samples were analysed using two-dimensional gas chromatography combined with time-of-flight mass spectrometry (GCxGC/TOFMS). A total of 865 heterocyclic compounds and 359 hydroxylated polycyclic aromatic hydrocarbons (PAHs) were detected in 16 tar samples produced by five different processes. The contents of both heterocyclic and hydroxylated PAHs varied greatly with the production process used, with the heterocyclic compounds giving information about the feedstock used. Of the 359 hydroxylated PAHs detected the majority would not have been be detected without the use of derivatization. Coal tars produced using different production processes and feedstocks yielded tars with significantly different heterocyclic and hydroxylated contents. The concentrations of the individual heterocyclic compounds varied greatly even within the different production processes and provided information about the feedstock used to produce the tars. The hydroxylated PAH content of the samples provided important analytical information that would otherwise not have been obtained without the use of derivatization and GCxGC/TOFMS. Copyright © 2017 John Wiley & Sons, Ltd.

  11. Tar removal from biosyngas in the biomass gasification process. (Liquid + liquid) equilibrium {water + solvent (paraxylene and methyl hexadecanoate) + model molecules of tar (benzene, toluene, phenol)}

    International Nuclear Information System (INIS)

    Bassil, Georgio; Mokbel, Ilham; Abou Naccoul, Ramy; Stephan, Juliette; Jose, Jacques; Goutaudier, Christelle

    2012-01-01

    Highlights: ► (Liquid + liquid) equilibria at atmospheric pressure. ► Solubility of benzene (or toluene or phenol) in paraxylene at (303 to 343) K. ► Solubility of benzene (or toluene or phenol) in methyl palmitate or methyl hexadecanoate at (303 to 343) K. ► Correlation of LLE using NRTL model. - Abstract: Tar is generated in the process by the condensation of the gas resulting from biomass gasification. The objective of this work is a contribution to the database on thermodynamic quantity which will be useful at the operation of tar removal from aqueous medium. With this aim, (liquid + liquid) equilibrium of {water + solvent (paraxylene and methyl hexadecanoate) + model molecules of tar (benzene, toluene, phenol)} was studied at temperatures (303.2, 323.2, and 343.2) K. The data obtained were correlated with the non-random two-liquid (NRTL) model.

  12. Profiling oil sands mixtures from industrial developments and natural groundwaters for source identification.

    Science.gov (United States)

    Frank, Richard A; Roy, James W; Bickerton, Greg; Rowland, Steve J; Headley, John V; Scarlett, Alan G; West, Charles E; Peru, Kerry M; Parrott, Joanne L; Conly, F Malcolm; Hewitt, L Mark

    2014-01-01

    The objective of this study was to identify chemical components that could distinguish chemical mixtures in oil sands process-affected water (OSPW) that had potentially migrated to groundwater in the oil sands development area of northern Alberta, Canada. In the first part of the study, OSPW samples from two different tailings ponds and a broad range of natural groundwater samples were assessed with historically employed techniques as Level-1 analyses, including geochemistry, total concentrations of naphthenic acids (NAs) and synchronous fluorescence spectroscopy (SFS). While these analyses did not allow for reliable source differentiation, they did identify samples containing significant concentrations of oil sands acid-extractable organics (AEOs). In applying Level-2 profiling analyses using electrospray ionization high resolution mass spectrometry (ESI-HRMS) and comprehensive multidimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOF/MS) to samples containing appreciable AEO concentrations, differentiation of natural from OSPW sources was apparent through measurements of O2:O4 ion class ratios (ESI-HRMS) and diagnostic ions for two families of suspected monoaromatic acids (GC × GC-TOF/MS). The resemblance between the AEO profiles from OSPW and from 6 groundwater samples adjacent to two tailings ponds implies a common source, supporting the use of these complimentary analyses for source identification. These samples included two of upward flowing groundwater collected <1 m beneath the Athabasca River, suggesting OSPW-affected groundwater is reaching the river system.

  13. Adsorption and transport of cadmium and rhodamine WT in pumice sand columns

    International Nuclear Information System (INIS)

    Pang, L.; Close, M.; Greenfield, H.; Stanton, G.

    2004-01-01

    The transport and attenuation of cadmium (Cd) and rhodamine WT (RWT) in a pumice sand aquifer media was investigated using column experiments to study a scenario of point-source contamination. A pore-water velocity of 1.7-1.8 m/day, which is a typical field groundwater velocity in a pumice sand aquifer system, was applied to triplicate columns. A pulse of a solution containing Cd and RWT, together with the conservative tracer tritiated water ( 3 H 2 O) at pH = 7, was introduced into the columns. Experimental results showed that concentration breakthrough curves (BTCs) of 3 H 2 O were symmetrical and fitted well into an equilibrium model. In contrast, BTCs of Cd and RWT were asymmetrical with significant tailings and fitted well with a two-site adsorption/desorption model. The symmetric 3 H 2 O BTCs suggest that physical non-equilibrium was absent in the experimental system, therefore the asymmetrical BTCs of Cd and RWT were attributed to chemical non-equilibrium. Modelling results showed that, in comparison with 3 H 2 O, Cd was apparently retarded by 101-108 times in pumice sand aquifer media (apparent adsorption coefficient 7.33-9.24 ml/g) and underwent a mass loss of 20-30% that was probably because of precipitation of CdCO 3 . As CdCO 3 is extremely insoluble, Cd precipitation would be irreversible and therefore it would not contribute to the tailing of the Cd BTCs. The experimental results suggest that the adsorption and desorption of Cd in pumice sand aquifer media in hydrodynamic conditions was a kinetic process. Cd desorption rates were two orders-of-magnitude slower than its adsorption rates. This resulted in a prolonged mean residence time for Cd in pumice sand aquifer media, which was 10-12 days in the 18-cm-long columns under a flow velocity of 1.7-1.8 m/day. Since the mean residence time is only indicative for the arrival of the central of mass in a contaminant BTC, the time required for the total disappearance of Cd will be much longer than the mean

  14. Influence of cigarette filter ventilation on smokers' mouth level exposure to tar and nicotine.

    Science.gov (United States)

    Caraway, John W; Ashley, Madeleine; Bowman, Sheri A; Chen, Peter; Errington, Graham; Prasad, Krishna; Nelson, Paul R; Shepperd, Christopher J; Fearon, Ian M

    2017-12-01

    Cigarette filter ventilation allows air to be drawn into the filter, diluting the cigarette smoke. Although machine smoking reveals that toxicant yields are reduced, it does not predict human yields. The objective of this study was to investigate the relationship between cigarette filter ventilation and mouth level exposure (MLE) to tar and nicotine in cigarette smokers. We collated and reviewed data from 11 studies across 9 countries, in studies performed between 2005 and 2013 which contained data on MLE from 156 products with filter ventilation between 0% and 87%. MLE among 7534 participants to tar and nicotine was estimated using the part-filter analysis method from spent filter tips. For each of the countries, MLE to tar and nicotine tended to decrease as filter ventilation increased. Across countries, per-cigarette MLE to tar and nicotine decreased as filter ventilation increased from 0% to 87%. Daily MLE to tar and nicotine also decreased across the range of increasing filter ventilation. These data suggest that on average smokers of highly ventilated cigarettes are exposed to lower amounts of nicotine and tar per cigarette and per day than smokers of cigarettes with lower levels of ventilation. Copyright © 2017 British American Tobacco. Published by Elsevier Inc. All rights reserved.

  15. The documentation of tar balls on oiled shorelines : lessons from the New Carissa, Oregon

    International Nuclear Information System (INIS)

    Owens, E.H.; Zimlicki-Owens, L.M.; Lamarche, A.; Reimer, P.D.; Martin, C.A.

    2000-01-01

    The New Carissa, carrying approximately 400,000 gallons of fuel oils ran aground on the outer shore of North Spit, in the vicinity of Coos Bay, Oregon, on February 4, 1999. The oil was released directly into the nearshore surf zone. Following the spill, a stretch of approximately 300 km of the coast of Oregon was surveyed and monitored. The need for the documentation of stranded tar balls in the neighbourhood of the spill site prompted the implementation of a long-term observation program. Initially, Shoreline Clean-up and Assessment Technique (SCAT) reporting procedures were required. Heavy oiling was followed by stranded oil taking the form of tar balls. The amount of oil on the shoreline decreased and the SCAT procedures alone were no longer adequate. They provided estimations of oil quantities that were too high and failed to provide any discrimination between amounts of oil observed on the beaches. A new reporting technique called Beach Assessment Reporting was designed to overcome the difficulties and record adequately the character and frequency of stranded tar balls. Maps, tables and histograms of stranded tar ball volumes and concentrations were discussed. Since the data spanned nine orders of magnitude at times, the semi-logarithmic scale time series plots of the concentration of the tar balls was used in order to identify trends. Conventional histograms only identified large values and camouflaged smaller trends in the time series. A direct method for describing tar ball concentrations geographically proved to be the use of weekly maximum tar ball concentration maps by segment. 10 refs., 2 tabs., 9 figs

  16. Comparative assessment of coal tars obtained from 10 former manufactured gas plant sites in the eastern United States

    Energy Technology Data Exchange (ETDEWEB)

    Brown, D.G.; Gupta, L.; Kim, T.H.; Moo-Young, H.K.; Coleman, A.J. [Lehigh University, Bethlehem, PA (United States). Dept. of Civil & Environmental Engineering

    2006-11-15

    A comparative analysis was performed on eleven coal tars obtained from former manufactured gas plant sites in the eastern United States. Bulk properties analyzed included percent ash, Karl Fisher water content, viscosity and average molecular weight. Chemical properties included monocyclic- and polycyclic-aromatic hydrocarbon (PAH) concentrations, alkylated aromatic concentrations, and concentrations of aliphatic and aromatic fractions. It was found that there was at least an order-of-magnitude variation in all properties measured between the eleven coal tars. Additionally, two coal tars obtained from the same manufactured gas plant site had very different properties, highlighting that there can be wide variations in coal tar properties from different samples obtained from the same site. Similarities were also observed between the coal tars. The relative chemical distributions were similar for all coal tars, and the coal tars predominantly consisted of PAHs, with naphthalene being the single-most prevalent compound. The C{sub 9-22} aromatic fraction, an indicator of all PAHs up to a molecular weight of approximately 276 g mole{sup -1}, showed a strong power-law relationship with the coal tar average molecular weight (MWct). And the concentrations of individual PAHs decreased linearly as MWct increased up to ca. 1000 g mole{sup -1}, above which they remained low and variable. Implications of these properties and their variation with MWct on groundwater quality are discussed. Ultimately, while these similarities do allow generalities to be made about coal tars, the wide range of coal tar bulk and chemical properties reported here highlights the complex nature of coal tars.

  17. Physicochemical Approaches for the Remediation of Former Manufactured Gas Plant Tars

    Science.gov (United States)

    Hauswirth, S.; Miller, C. T.

    2014-12-01

    Former manufactured gas plant (FMGP) tars are one of the most challenging non-aqueous phase liquid (NAPL) contaminants to remediate due to their complex chemical composition, high viscosities, and ability to alter wettability. In this work, we investigate several in situ remediation techniques for the removal of tar from porous media. Batch and column experiments were conducted to test the effectiveness of mobilization, solubilization, and chemical oxidation remediation approaches. Alkaline (NaOH), surfactant (Triton X-100), and polymer (xanthan gum) agents were used in various combinations to reduce tar-water interfacial tension, increase flushing solution viscosity, and increase the solubilities of tar components. Base-activated sodium persulfate was used alone and in combination with surfactant to chemically oxidized tar components. The effectiveness of each method was assessed in terms of both removal of PAHs from the system and reduction of dissolved-phase effluent polycyclic aromatic hydrocarbon (PAH) concentrations. In column studies, alkaline-polymer (AP) and alkaline-surfactant-polymer (ASP) solutions efficiently mobilized 81-93% and 95-96% of residual PAHs, respectively, within two pore volumes. The impact of AP flushing on dissolved-phase PAH concentrations was relatively low; however, the concentrations of several low molar mass PAHs were significantly reduced after ASP flushing. Surfactant-polymer (SP) solutions removed over 99% of residual PAHs through a combination of mobilization and solubilization, and reduced the post-remediation, dissolved-phase total PAH concentration by 98.4-99.1%. Degradation of residual PAHs by base-activated sodium persulfate was relatively low (30-50%), and had little impact on dissolved-phase PAH concentrations.

  18. Cold Preparation of Heroin in a Black Tar Market.

    Science.gov (United States)

    Roth, Alexis M; Armenta, Richard F; Wagner, Karla D; Strathdee, Steffanie A; Goldshear, Jesse L; Cuevas-Mota, Jazmine; Garfein, Richard S

    2017-07-29

    Black tar heroin is typically prepared for injection with heat which decreases the risk of HIV transmission by inactivating the virus. We received reports that persons who inject drugs (PWID) in Tijuana, Baja California, Mexico, a black tar heroin market, were using only water to dissolve heroin. Because Tijuana abuts San Diego County, CA, United States, we undertook the present analyses to determine the prevalence of this practice among PWID in San Diego, California. PWID completed quarterly behavioral assessments and serological testing for blood-borne viruses. Bivariate and multivariable logistic regression models were constructed to assess for individual, social, and structural correlates of preparing heroin without heat within the preceding 6 months. Nearly half of black tar heroin users (149/305) reported they had prepared heroin without heat within 6 months. In multivariable analysis, cold preparation was independently associated with younger age (10 year decrease; AOR = 1.25; 95% CI 1.03, 1.53), more drug injecting acquaintances (per 5 acquaintance increase; AOR = 1.05; 95% CI 1.01, 1.09) and prefilled syringe use (injecting drugs from syringes that are already filled with drugs before purchase; AOR = 1.86; 95% CI 1.14, 3.02). Conclusions/Importance: To our knowledge, this is the first paper to report that PWID living in a black tar heroin market are preparing heroin without heat. Additional research is needed to determine whether this is an endemic practice or PWID are engaging in new forms of drug preparation in response to changes in the environment.

  19. Enhanced characterization of oil sands acid-extractable organics fractions using electrospray ionization-high-resolution mass spectrometry and synchronous fluorescence spectroscopy.

    Science.gov (United States)

    Bauer, Anthony E; Frank, Richard A; Headley, John V; Peru, Kerry M; Hewitt, L Mark; Dixon, D George

    2015-05-01

    The open pit oil sands mining operations north of Fort McMurray, Alberta, Canada, are accumulating tailings waste at a rate approximately equal to 4.9 million m(3) /d. Naphthenic acids are among the most toxic components within tailings to aquatic life, but structural components have largely remained unidentified. In the present study, electrospray ionization high-resolution mass spectrometry (ESI-HRMS) and synchronous fluorescence spectroscopy (SFS) were used to characterize fractions derived from the distillation of an acid-extractable organics (AEO) mixture isolated from oil sands process-affected water (OSPW). Mean molecular weights of each fraction, and their relative proportions to the whole AEO extract, were as follows: fraction 1: 237 Da, 8.3%; fraction 2: 240 Da, 23.8%; fraction 3: 257 Da, 26.7%; fraction 4: 308 Da, 18.9%; fraction 5: 355 Da, 10.0%. With increasing mean molecular weight of the AEO fractions, a concurrent increase occurred in the relative abundance of nitrogen-, sulfur-, and oxygen-containing ions, double-bond equivalents, and degree of aromaticity. Structures present in the higher-molecular-weight fractions (fraction 4 and fraction 5) suggested the presence of heteroatoms, dicarboxyl and dihydroxy groups, and organic acid compounds with the potential to function as estrogens. Because organic acid compositions become dominated by more recalcitrant, higher-molecular-weight acids during natural degradation, these findings are important in the context of oil sands tailings pond water remediation. © 2015 SETAC.

  20. Conservation and reclamation at Alberta's mineable oil sands

    Energy Technology Data Exchange (ETDEWEB)

    Purdy, B.; Richens, T. [Alberta Environment, Edmonton, AB (Canada)

    2010-07-01

    The regulatory foundation for oil sands in this region is established by the Energy Resources Conservation Board, Environmental Protection and Enhancement Act (EPEA), as well as the Water Act. This presentation discussed the regulatory foundation for conservation and reclamation in the mineable oil sands region. EPEA requirements and conservation objectives were identified. EPEA conservation and reclamation requirements stipulate that an operator must conserve and reclaim and obtain a reclamation certificate. EPEA approvals that were presented compared prescriptive standards versus meeting outcomes at certification. Operational and management challenges as well as the role of research networks and multi-stakeholder organizations were also addressed. Challenge facing the industry include progressive reclamation; tailings management and process-affected water; reclamation certification; integrated landscapes; soil handling and revegetation and monitoring and research. The presentation demonstrated that reclamation begins with mine planning and ends with certification. figs.

  1. The purification of coal tar by the addition of quinoline and Zn(oh)/sub 2/

    International Nuclear Information System (INIS)

    Zhou, P.; Chen, Q.L.; Ao, X.Q.; Kang, C

    2017-01-01

    The coal tar was purified by the addition of quinoline and Zn(OH)2, in order to decrease the content of carbon and inorganic oxide particles. The effect on the viscosity and ash content of the coal tar were investigated by altering temperature, time, and the amount of quinolone and Zn(OH)2 . When the volume ratio between quinolone and coal tar was 20:1 and the static time was 24 h. The viscosity of three layers decreased with rising temperature. When the static temperature and time was 45 °C and 24 h, respectively. The viscosity of three layers decreased with the arising amount of quinoline. And when the volume ratio between quinolone and coal tar was 20:1 and the temperature was 45 °C. The viscosity of three layers decreased first and then increased with the prolonging of static time. And when the static time of coal tar was 24 h, the viscosity of coal tar is the lowest. Because of the lower viscosity of coal tar, decreasing the content of carbon and ash particles in upper and middle layer, the ash content decreased from 0.168% to 0.092%. The addition of Zn(OH)2 can lead ash content in middle layer decrease to 0.058%. Zn2SiO4 and ZnAl2O4 may be produced due to the reaction between Zn (OH) 2 and SiO2 or Al2O3, which can settle down easily. The results show that the content of carbon and inorganic oxide particles in upper-middle-class (the middle 4/5 of the whole volume) decreased with the addition of quinolone and Zn(OH)2 . When the volume ratio between quinolone and coal tar was 50:2, quality ratio between coal tar and Zn(OH)2 was 20000:1, the mixture were heated up to 45 °C at atmospheric pressure and keeping this constant temperature for 24 h, the ash content in upper-middle-class can decreased to 0.058%. (author)

  2. Opening of the TAR hairpin in the HIV-1 genome causes aberrant RNA dimerization and packaging

    Directory of Open Access Journals (Sweden)

    Das Atze T

    2012-07-01

    Full Text Available Abstract Background The TAR hairpin is present at both the 5′ and 3′ end of the HIV-1 RNA genome. The 5′ element binds the viral Tat protein and is essential for Tat-mediated activation of transcription. We recently observed that complete TAR deletion is allowed in the context of an HIV-1 variant that does not depend on this Tat-TAR axis for transcription. Mutations that open the 5′ stem-loop structure did however affect the leader RNA conformation and resulted in a severe replication defect. In this study, we set out to analyze which step of the HIV-1 replication cycle is affected by this conformational change of the leader RNA. Results We demonstrate that opening the 5′ TAR structure through a deletion in either side of the stem region caused aberrant dimerization and reduced packaging of the unspliced viral RNA genome. In contrast, truncation of the TAR hairpin through deletions in both sides of the stem did not affect RNA dimer formation and packaging. Conclusions These results demonstrate that, although the TAR hairpin is not essential for RNA dimerization and packaging, mutations in TAR can significantly affect these processes through misfolding of the relevant RNA signals.

  3. Oil sands development update

    International Nuclear Information System (INIS)

    1999-01-01

    A detailed review and update of oil sands development in Alberta are provided covering every aspect of the production and economic aspects of the industry. It is pointed out that at present oil sands account for 28 per cent of Canadian crude oil production, expected to reach 50 per cent by 2005. Based on recent announcements, a total of 26 billion dollars worth of projects are in progress or planned; 20 billion dollars worth of this development is in the Athabasca area, the remainder in Cold Lake and other areas. The current update envisages up to 1,800,000 barrels per day by 2008, creating 47,000 new jobs and total government revenues through direct and indirect taxes of 118 billion dollars. Provinces other than Alberta also benefit from these development, since 60 per cent of all employment and income created by oil sands production is in other parts of Canada. Up to 60 per cent of the expansion is for goods and services and of this, 50 to 55 per cent will be purchased from Canadian sources. The remaining 40 per cent of the new investment is for engineering and construction of which 95 per cent is Canadian content. Aboriginal workforce by common consent of existing operators matches regional representation (about 13 per cent), and new developers are expected to match these standards. Planned or ongoing development in environmental protection through improved technologies and optimization, energy efficiency and improved tailings management, and active support of flexibility mechanisms such as emission credits trading, joint implementation and carbon sinks are very high on the industry's agenda. The importance of offsets are discussed extensively along with key considerations for international negotiations, as well as further research of other options such as sequestration, environmentally benign disposal of waste, and enhanced voluntary action

  4. Material Properties and Characteristics for Development of an Expert System for Coal-Tar Sealers

    National Research Council Canada - National Science Library

    Shoenberger, James

    2001-01-01

    .... Several coal-tar mixtures that varied with source of the coal-tar emulsion, amount of aggregate, and amount of polymer used in the mixtures were evaluated for their field performance and material properties...

  5. Column bioleaching of arsenic and Heavy metals from gold mine tailings by aspergillus fumigatus

    International Nuclear Information System (INIS)

    Seh-Bardan, Bahi Jalili; Othman, Radziah; Ab Wahid, Samsuri; Husin, Aminudin; Sadegh-Zadeh, Fardin

    2012-01-01

    A column bioleaching experiment was carried out to compare the effectiveness of the fungus Aspergillus fumigatus to bioleach arsenic (As) and heavy metals from the tailings using two different methods. In the first method, which is named as distribution method (DM), the fungus was distributed in the column by means of vertical and horizontal layers of coarse sand. In the other method, named as surface applied method (SAM), the fungus was cultivated on the surface of the tailings, which was covered with a few centimeters of coarse sand. Results showed that in the DM, oxalic acid production was stimulated and maximum removal of As, Fe, Mn, and Zn was 53, 51, 81, and 62%, respectively. However, Pb removal was low (8%), which might be due to the precipitation of Pb as its oxalates. On the other hand, the maximum removal of As, Fe, Mn, Pb, and Zn were 22, 28, 37, 64, and 34%, respectively, for the SAM. Results of the sequential extraction study showed that the DM was effective in removing the water soluble, exchangeable, carbonate, and Fe/Mn oxide fractions of As, Fe, Mn, and Zn. Our study suggested that A. fumigatus has a potential to be used in remediation of heavy metal contaminated sites. Distributing the fungus throughout the entire tailings columns improved the bioleaching of heavy metals by the fungus. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Column bioleaching of arsenic and Heavy metals from gold mine tailings by aspergillus fumigatus

    Energy Technology Data Exchange (ETDEWEB)

    Seh-Bardan, Bahi Jalili; Othman, Radziah; Ab Wahid, Samsuri; Husin, Aminudin; Sadegh-Zadeh, Fardin [Faculty of Agriculture, Department of Land Management, Universiti Putra Malaysia, Serdang, Selangor (Malaysia)

    2012-06-15

    A column bioleaching experiment was carried out to compare the effectiveness of the fungus Aspergillus fumigatus to bioleach arsenic (As) and heavy metals from the tailings using two different methods. In the first method, which is named as distribution method (DM), the fungus was distributed in the column by means of vertical and horizontal layers of coarse sand. In the other method, named as surface applied method (SAM), the fungus was cultivated on the surface of the tailings, which was covered with a few centimeters of coarse sand. Results showed that in the DM, oxalic acid production was stimulated and maximum removal of As, Fe, Mn, and Zn was 53, 51, 81, and 62%, respectively. However, Pb removal was low (8%), which might be due to the precipitation of Pb as its oxalates. On the other hand, the maximum removal of As, Fe, Mn, Pb, and Zn were 22, 28, 37, 64, and 34%, respectively, for the SAM. Results of the sequential extraction study showed that the DM was effective in removing the water soluble, exchangeable, carbonate, and Fe/Mn oxide fractions of As, Fe, Mn, and Zn. Our study suggested that A. fumigatus has a potential to be used in remediation of heavy metal contaminated sites. Distributing the fungus throughout the entire tailings columns improved the bioleaching of heavy metals by the fungus. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Ecotoxicological impacts of effluents generated by oil sands bitumen extraction and oil sands lixiviation on Pseudokirchneriella subcapitata

    Energy Technology Data Exchange (ETDEWEB)

    Debenest, T., E-mail: tdebenest@yahoo.fr [Environment Canada, Fluvial Ecosystem Research, 105 McGill Street, 7 floor, Montreal, Quebec, H2Y 2E7 (Canada); Turcotte, P. [Environment Canada, Fluvial Ecosystem Research, 105 McGill Street, 7 floor, Montreal, Quebec, H2Y 2E7 (Canada); Gagne, F., E-mail: francois.gagne@ec.gc.ca [Environment Canada, Fluvial Ecosystem Research, 105 McGill Street, 7 floor, Montreal, Quebec, H2Y 2E7 (Canada); Gagnon, C.; Blaise, C. [Environment Canada, Fluvial Ecosystem Research, 105 McGill Street, 7 floor, Montreal, Quebec, H2Y 2E7 (Canada)

    2012-05-15

    The exploitation of Athabasca oil sands deposits in northern Alberta has known an intense development in recent years. This development has raised concern about the ecotoxicological risk of such industrial activities adjacent to the Athabasca River. Indeed, bitumen extraction generated large amounts of oil sands process-affected water (OSPW) which are discharged in tailing ponds in the Athabasca River watershed. This study sought to evaluate and compare the toxicity of OSPW and oil sands lixiviate water (OSLW) with a baseline (oil sands exposed to water; OSW) on a microalgae, Pseudokirchneriella subcapitata, at different concentrations (1.9, 5.5, 12.25, 25 and 37.5%, v/v). Chemical analyses of water-soluble contaminants showed that OSPW and OSLW were enriched in different elements such as vanadium (enrichment factor, EF = 66 and 12, respectively), aluminum (EF = 64 and 15, respectively), iron (EF = 52.5 and 17.1, respectively) and chromium (39 and 10, respectively). The toxicity of OSPW on cells with optimal intracellular esterase activity and chlorophyll autofluorescence (viable cells) (72 h-IC 50% < 1.9%) was 20 times higher than the one of OSW (72 h-IC 50% > 37.5%, v/v). OSLW was 4.4 times less toxic (IC 50% = 8.5%, v/v) than OSPW and 4.5 times more toxic than OSW. The inhibition of viable cell growth was significantly and highly correlated (<-0.7) with the increase of arsenic, beryllium, chromium, copper, lead, molybdenum and vanadium concentrations. The specific photosynthetic responses studied with JIP-test (rapid and polyphasic chlorophyll a fluorescence emission) showed a stimulation of the different functional parameters (efficiency of PSII to absorb energy from photons, size of effective PSII antenna and vitality of photosynthetic apparatus for energy conversion) in cultures exposed to OSPW and OSLW. To our knowledge, our study highlights the first evidence of physiological effects of OSPW and OSLW on microalgae.

  8. Biomass Gasifier ''Tars'': Their Nature, Formation, and Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Milne, T. A.; Evans, R. J. (National Renewable Energy Laboratory); Abatzaglou, N. (Kemestrie, Inc.)

    1998-11-01

    The main purpose of this review is to update the information on gasification tar, the most cumbersome and problematic parameter in any gasification commercialization effort. The work aims to present to the community the scientific and practical aspects of tar formation and conversion (removal) during gasification as a function of the various technological and technical parameters and variables.

  9. 78 FR 29379 - BLM Director's Response to the Appeal by the Governors of Utah and Wyoming of the BLM Assistant...

    Science.gov (United States)

    2013-05-20

    ... Shale and Tar Sands Resources on Lands Administered by the Bureau of Land Management (BLM) in Colorado... Shale and Tar Sands Resources on Lands Administered by the BLM in Colorado, Utah, and Wyoming, which..., Lakewood, CO 80215 or Mitchell Leverette, BLM Division Chief, Solid Minerals, 202-912-7113, ( [email protected

  10. Evaluation of respirable particle matter in gold mine tailings on the Witwatersrand

    International Nuclear Information System (INIS)

    Ojelede, M.E.; Annegarn, H.J.

    2007-01-01

    Within the Witwatersrand gold mining area of South Africa, wind-blown dust is a significant contributor to atmospheric air pollution brought to the fore with the reworking of old mine tailings. Approximately 40,000 hectares are covered with tailings in the Witwatersrand. Wind-erosion during late austral winter and early spring causes surfaces of these tailings to be exposed, particularly during higher wind speeds and in the absence of rainfall. Local residents complain as the surrounding areas experience unpleasant dust episodes. As a result of urban PM 10 and PM 2.5 respirable particulate matter, increased respiratory ailments, morbidity and mortality, and concerns about the health impacts of wind-blown mine tailings in South Africa have been reported. Since 1981, significant monitoring of dustfall has taken place on the Witwatersrand, however, characterization of the respirable fraction of gold mine tailings material and dustfall is lacking. This paper presented the results of a study that established the content of respirable particulate matter in exposed mine tailings and wind-blown dust, and their likely contributions to ambient air. The initial results of the particulate size distribution of material samples from tailings and dust deposits collected in ambient dustfall-monitors were provided. Particle size distributions from different deposit types include slimes and sand deposits, surface and core material, and wind-winnowed secondary deposits. Fractions of PM 10 in source and deposited material were also discussed. It was concluded that there was a significant fraction of PM 10 material in the mine tailings, and that further work to quantify the population exposure risk is needed. 11 refs., 1 tab., 6 figs

  11. Dual vapor extraction on acidic sludge tar at a former refinery

    International Nuclear Information System (INIS)

    Lear, P.R.; Beall, P.; Townsend, S.

    1996-01-01

    OHM Remediation Services Corp conducted a pilot-scale demonstration for a novel application of dual vapor extraction technology for the pretreatment of the acid tar sludge material. The acid tar sludge comprised of approximately 60% asphaltene hydrocarbon material, 20% clay, and up to 20% sulfuric acid (H 2 SO 4 ). The liquid layer in the bottom of the pits has a low pH ( 2 ) gas which is released with the sludge material is excavated or handled. The objective of the dual vapor extraction was to remove the SO 2 vapors and liquid layer containing sulfuric acid prior to any further treatment. The dual vapor extraction would reduce the amount of alkaline reagent required for neutralization while eliminating the health and safety concerns. Overall, the DVE pilot demonstration successfully showed that both liquids and vapors could be removed from the acid tar sludge material. The liquid present in the lower portions of the pits will have pH values of 1.0 or less and acidities on the order of 5% H 2 SO 4 . The liquid removed from the acid tar sludge material by a DVE system will have slightly higher pH (∼1.5) and lower alkalinities (∼3% H 2 SO 4 ). The SO 2 concentration in the vapors removed by the DVE system will be variable with initial levels approaching 1,200 ppmv SO 2 . The SO 2 concentration in the vapor phase should decrease with time. A caustic scrubber solution will remove any SO 2 from the vapor phase. After DVE treatment, the acid tar sludge material would have a slightly increased pH and a decreased SO 2 concentration

  12. Toxicity of coal-tar and asphalt sealants to eastern newts, Notophthalmus viridescens

    Energy Technology Data Exchange (ETDEWEB)

    Bommarito, T.; Sparling, D.W.; Halbrook, R.S. [South Illinois University, Carbondale, IL (United States). Cooperative Wildlife Research Laboratory

    2010-09-15

    Between 1970 and 2000 the concentration of total polycyclic aromatic hydrocarbons (TPAH) in several lakes across the country increased whereas those of other persistent organic pollutants (POPs) tended to remain stable or declined. Urbanized watersheds experienced greater rises in TPAH concentration compared to non-urban lakes. Sources for urban PAHs include industrial wastes, vehicular exhausts and oil leaks and sealants from pavement surfaces. Both coal-tar and asphalt sealants are used to protect surfaces but runoff from surfaces coated with coal-tar can have mean concentrations of 3500 mg TPAHs kg{sup -1}, much higher than runoff from asphalt-sealed or cement surfaces. Unaltered parent compounds of PAHs can have many lethal and sublethal toxic effects, but oxidation and UV radiation can alter the toxicity of these compounds, sometimes creating degradates that are many times more toxic than parent compounds. The purposes of this study were to determine if coal-tar sealants can be toxic to adult eastern newts (Notophthalmus viridescens) and to compare the toxicity of coal-tar sealant to that of asphalt sealant. Newts were exposed to sediments containing dried sealants ranging from 0 mg kg{sup -1} to 1500 mg kg{sup -1} under simultaneous exposure to UV radiation and visible light to determine concentration/response relationships. No significant mortality occurred with any treatment. Significant effects due to sealants included decreased righting ability and diminished liver enzyme activities. Coal-tar sealant was more effective in inducing these changes than was asphalt sealant.

  13. Effects of oil sands waste water on the wood frog (rana sylvatica)

    Energy Technology Data Exchange (ETDEWEB)

    Hersikorn, B.; Smits, J.E. [Saskatchewan Univ., Regina, SK (Canada)

    2007-07-01

    The sustainability of various reclamation strategies can be determined by the growth and health of indigenous amphibians (Wood Frogs). This paper referred to the large quantities of tailings water that are generated by oil sand extraction activities. It presented the results of a study that was conducted in the spring and summer of 2006 and 2007 on reclaimed formation wetlands comprising tailings water. The objective was to understand the impact of these wetlands on native amphibians. Frogs were exposed to wetlands containing oil sands process affected water (OSPW) and reference water (no OSPW). Six experimental trenches were made at one site in the first year. Each trench had 3 enclosures with 50 tadpoles. In the second year, there were 13 sites, including 6 reference and 7 OSPW affected sites, which were classified as old (more than 8 yrs) or young (less than 7 yrs). Four enclosures, with 50 tadpoles each, were placed in each wetland. The study involved the evaluation of growth rate, survival, time to metamorphosis, thyroid hormone concentrations, liver EROD activity, and tissue retinol concentrations. In addition, stable isotopes were used to track carbon flow from primary production plants, through the food chain, to tadpoles and frogs which represent intermediate and higher trophic levels in reclaimed wetlands.

  14. Tar analysis from biomass gasification by means of online fluorescence spectroscopy

    Science.gov (United States)

    Baumhakl, Christoph; Karellas, Sotirios

    2011-07-01

    Optical methods in gas analysis are very valuable mainly due to their non-intrusive character. That gives the possibility to use them for in-situ or online measurements with only optical intervention in the measurement volume. In processes like the gasification of biomass, it is of high importance to monitor the gas quality in order to use the product gas in proper machines for energy production following the restrictions in the gas composition but also improving its quality, which leads to high efficient systems. One of the main problems in the biomass gasification process is the formation of tars. These higher hydrocarbons can lead to problems in the operation of the energy system. Up to date, the state of the art method used widely for the determination of tars is a standardized offline measurement system, the so-called "Tar Protocol". The aim of this work is to describe an innovative, online, optical method for determining the tar content of the product gas by means of fluorescence spectroscopy. This method uses optical sources and detectors that can be found in the market at low cost and therefore it is very attractive, especially for industrial applications where cost efficiency followed by medium to high precision are of high importance.

  15. Tar ball concentrations in the ocean around the Cape of Good Hope before and after a major oil spill

    Energy Technology Data Exchange (ETDEWEB)

    Eagle, G A; Green, A; Williams, J

    1979-11-01

    From August 1977 to August 1978, tar ball concentrations around the southwestern coast of South Africa were sampled. Prior to a tanker collision on December 16, 1977, the area was relatively free of floating tar. Following the collision, tar ball concentrations increased; tar was transported by wind and currents, at average speeds of about 1 km/hr. In areas of slack currents, tar was observed for as long as 8 months after the spill. Results provided information about surface current trends.

  16. Determination of oxygen, nitrogen, and silicon in Nigerian fossil fuels by 14 MeV neutron activation analysis

    International Nuclear Information System (INIS)

    Hannan, M.A.; Oluwole, A.F.; Kehinde, L.O.; Borisade, A.B.

    2003-01-01

    Classification, assessment, and utilization of coal and crude oil extracts are enhanced by analysis of their oxygen content. Values of oxygen obtained 'by difference' from chemical analysis have proved inaccurate. The oxygen, nitrogen, and silicon content of Nigerian coal samples, crude oils, bitumen extracts, and tar sand samples were measured directly using instrumental fast neutron activation analysis (FNAA). The total oxygen in the coal ranges from 5.20% to 23.3%, in the oil and extracts from 0.14% to 1.08%, and in the tar sands from 38% to 47%. The nitrogen content in the coal ranges from 0.54% to 1.35%, in the crude oil and bitumen extracts from ≤ 0.014% to 0.490%, and in the tar sands from 0.082% to 0.611%. The silicon content in the coal ranges from 1.50% to 8.86%; in the oil and the bitumen extracts it is <1%, and in the tar sands between 25.1% and 37.5%. The results show that Nigerian coals are mostly sub-bituminous. However, one of the samples showed bituminous properties as evidenced by the dry ash-free (daf) percent of carbon obtained. This same sample indicated a higher ash content resulting in a comparatively high percentage of silicon. In oils and tar sands from various locations, a comparison of elements is made. (author)

  17. Analysis of disposal of uranium mill tailings in a mined out open pit

    International Nuclear Information System (INIS)

    Staub, W.P.; Triegel, E.K.

    1978-01-01

    Mined out open pits are presently under consideration as disposal sites for uranium mill tailings. In this method of tailings management, the escape of contaminated liquid into an adjacent aquifer is the principal environmental concern. The modified Bishop Method was used to analyze the structural stability of a clay liner along the highwall and fluid flow models were used to analyze the effect of tailings solutions on ground water under several operating conditions. Results of the slope stability analysis showed that it would be necessary to construct the clay liner as a modified form of engineered embankment. This embankment would be similar in construction to that of an earthfill dam. It could be constructed on a 1:1 slope provided the tailings slurry were managed properly. It would be necessary to maintain the freeboard height between the embankment and tailings at less than 4 m. A partially dewatered sand beach would have to be located adjacent to the embankment. Potential leakage and aquifer contamination was modeled for lined and unlined pits of various designs. Sulfate, and possibly U and Th, are the most likely contaminants. Results from the model showed the clay and soil cement lined pit to be most effective in containing the pollutants

  18. Skin cancer in patients with psoriasis treated with coal tar. A 25-year follow-up study

    International Nuclear Information System (INIS)

    Pittelkow, M.R.; Perry, H.O.; Muller, S.A.; Maughan, W.Z.; O'Brien, P.C.

    1981-01-01

    For many years, crude coal tar has been used for the treatment of psoriasis. The possible carcinogenic effect of crude coal tar and ultraviolet (UV) radiation (Goeckerman regimen), considered individually or in combination, has been of some concern to physicians. A 25-year follow-up study was completed on 280 patients with psoriasis who were hospitalized and treated with crude coal tar and UV radiation at the Mayo Clinic, Rochester, Minn, during the years 1950 through 1954. The results of this study suggest that the incidence of skin cancer is not appreciably increased above the expected incidence for the general population when patients are treated with coal tar ointments. It seems that the Goeckerman regimen (topical crude coal tar combined with UV radiation) can be used with minimal risk for skin cancer in the treatment of psoriasis

  19. Volatilization of polycyclic aromatic hydrocarbons from coal-tar-sealed pavement

    Science.gov (United States)

    Van Metre, Peter C.; Majewski, Michael S.; Mahler, Barbara J.; Foreman, William T.; Braun, Christopher L.; Wilson, Jennifer T.; Burbank, Teresa L.

    2012-01-01

    Coal-tar-based pavement sealants, a major source of PAHs to urban water bodies, are a potential source of volatile PAHs to the atmosphere. An initial assessment of volatilization of PAHs from coal-tar-sealed pavement is presented here in which we measured summertime gas-phase PAH concentrations 0.03 m and 1.28 m above the pavement surface of seven sealed (six with coal-tar-based sealant and one with asphalt-based sealant) and three unsealed (two asphalt and one concrete) parking lots in central Texas. PAHs also were measured in parking lot dust. The geometric mean concentration of the sum of eight frequently detected PAHs (ΣPAH8) in the 0.03-m samples above sealed lots (1320 ng m-3) during the hottest part of the day was 20 times greater than that above unsealed lots (66.5 ng m-3). The geometric mean concentration in the 1.28-m samples above sealed lots (138 ng m-3) was five times greater than above unsealed lots (26.0 ng m-3). Estimated PAH flux from the sealed lots was 60 times greater than that from unsealed lots (geometric means of 88 and 1.4 μg m-2 h-1, respectively). Although the data set presented here is small, the much higher estimated fluxes from sealed pavement than from unsealed pavement indicate that coal-tar-based sealants are emitting PAHs to urban air at high rates compared to other paved surfaces.

  20. Oil sands mining and reclamation cause massive loss of peatland and stored carbon

    Science.gov (United States)

    Rooney, Rebecca C.; Bayley, Suzanne E.; Schindler, David W.

    2012-01-01

    We quantified the wholesale transformation of the boreal landscape by open-pit oil sands mining in Alberta, Canada to evaluate its effect on carbon storage and sequestration. Contrary to claims made in the media, peatland destroyed by open-pit mining will not be restored. Current plans dictate its replacement with upland forest and tailings storage lakes, amounting to the destruction of over 29,500 ha of peatland habitat. Landscape changes caused by currently approved mines will release between 11.4 and 47.3 million metric tons of stored carbon and will reduce carbon sequestration potential by 5,734–7,241 metric tons C/y. These losses have not previously been quantified, and should be included with the already high estimates of carbon emissions from oil sands mining and bitumen upgrading. A fair evaluation of the costs and benefits of oil sands mining requires a rigorous assessment of impacts on natural capital and ecosystem services. PMID:22411786

  1. Canada's oil sands: nuclear power in an integrated energy economy

    Energy Technology Data Exchange (ETDEWEB)

    Isaacs, E. [Alberta Energy Research Inst., Alberta (Canada)

    2008-06-15

    At a time of the expansive global growth in energy demand and the peaking of conventional oil, the Canadian Oil Sands have emerged as the largest new reserves to supply oil to world markets. Bitumen production in 2006 averaged 1.25 million barrels per day (an increase of 13% over 2005 and an 88% increase since 2000). If this trend continues Canada will be positioned as one of the world's premier suppliers of oil for many decades to come. The Oil Sands are one of the world's most challenging and complex oil resources. They require considerable amount of energy, water and land area to produce, resulting in contaminated tailings ponds, air emissions of concern and copious greenhouse gas (GHG) emissions. As the need to protect the environment and reduce GHG emissions moves higher on the public agenda Canada's ability to grow the energy supplies from oil sands will be severely tested. This paper focuses on the current and emerging methods and innovations that can be applied to produce these unconventional resources to value-added products with a decreasing impact on the environment. The paper will also describe the benefits and challenges for nuclear energy in the oil sands as a solution to the need for substitutes for natural gas in oil sands production and upgrading and in meeting Canada's GHG emission targets. (author)

  2. Detailed grouping and functional composition of neutral substances in low-temperature tar

    Energy Technology Data Exchange (ETDEWEB)

    Kalechits, I V; Salimgareeva, F G; Popova, N I; Kurbangaleeva, D K; Klykova, G G

    1955-01-01

    The grouping and the functional composition of the neutral substances in coal tar were characterized by means of adsorption on silica gel with subsequent chemical analysis of each fraction. The neutral materials were obtained by consecutive treatment of a C/sub 6/H/sub 6/ solution of coal tar with 10 percent alkali and 5 percent H/sub 2/SO/sub 4/ to remove the phenols and the bases. The data show that of the neutral substances (only 75% were identified) 40.5% were aromatic hydrocarbons. Based on a study of all of the data, it was proposed that 90% of the composition of coal tars is aromatic. The physical constants of the separated fractions were determined and are presented in tabular form.

  3. Process for removing heavy metal compounds from heavy crude oil

    Science.gov (United States)

    Cha, Chang Y.; Boysen, John E.; Branthaver, Jan F.

    1991-01-01

    A process is provided for removing heavy metal compounds from heavy crude oil by mixing the heavy crude oil with tar sand; preheating the mixture to a temperature of about 650.degree. F.; heating said mixture to up to 800.degree. F.; and separating tar sand from the light oils formed during said heating. The heavy metals removed from the heavy oils can be recovered from the spent sand for other uses.

  4. Report and recommendations of the task force on tree and shrub planting on active oil sands tailings dams

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-02-15

    In oil sands reclamation operations in Canada there is a conflict between dam safety and the planting of trees and woody shrubs. Indeed, tree planting is being restricted on the downstream slopes of dams to avoid damage to drains and to ensure the integrity of visual and instrumentation monitoring conflicting thus with progressive reclamation. Alberta Environment hired the Oil Sands Research and Information Network (OSRIN), an independent organization which analyzes and interprets available knowledge on soil and water reclamation in the oil sands mining sector, to address this issue and make recommendations. The organization appointed a Task Force which presented its final report in March 2011. The Task Force recommended that the Engineer of Record should be responsible for determining the tree and shrub planting zones and that he should submit his plans to Alberta Environment for approval.

  5. Investigation of sulfur-polycyclic aromatic hydrocarbon in coal derived tars of pyrolysis and hydropyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Chen, H.; Li, B.; Zhang, B. [Chinese Academy of Sciences, Taiyuan (China). State Key Laboratory of Coal Conversion

    1999-07-01

    A study was undertaken to characterize sulphur forms in coal derived tars from pyrolysis and hydropyrolysis of bituminous coal and lignite. The pyrolysis tars were analyzed for content of polycyclic aromatic sulfur hydrocarbons (PASH). 5 refs., 3 figs., 3 tabs.

  6. A look at one of the world`s largest apron feeder drives - Alberta Oil Sands Project

    Energy Technology Data Exchange (ETDEWEB)

    Persson, O. [Hagglunds Drives Canada Inc., Vancouver, BC (Canada)

    1999-10-01

    Various types of equipment to transport tar sands to processing plants are discussed, with special attention to the advantages of hydraulic direct drives over conventional electro-mechanical drives. A hydraulic direct drive such as the Hagglund Drive has exceptional starting torque capacity due to the high torque capability of the hydraulic motor. As such, it can be particularly useful in applications where shock loads occur with some frequency, or where many starts and stops are needed. Application of the Hagglund drive to power one of the world`s largest apron feeders in the Alberta Oil Sands is described as an illustration of the exceptional reliability, productivity and performance of this equipment. It has about one five-hundredth of the inertia of an equivalent high speed drive with gear reducer, a feature which is particularly significant in the case of feeders which are known to suffer much downtime due to chain related problems. These types of drives have also been used to great advantage in the process industries like pulp and paper, chemical, rubber and plastics, recycling and steel. 1 tab., 1 fig.

  7. Crystallization and preliminary X-ray diffraction analysis of the periplasmic domain of the Escherichia coli aspartate receptor Tar and its complex with aspartate

    Energy Technology Data Exchange (ETDEWEB)

    Mise, Takeshi; Matsunami, Hideyuki; Samatey, Fadel A.; Maruyama, Ichiro N., E-mail: ichi@oist.jp [Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami, Okinawa 904-0495 (Japan)

    2014-08-27

    The periplasmic domain of the E. coli aspartate receptor Tar was cloned, expressed, purified and crystallized with and without bound ligand. The crystals obtained diffracted to resolutions of 1.58 and 1.95 Å, respectively. The cell-surface receptor Tar mediates bacterial chemotaxis toward an attractant, aspartate (Asp), and away from a repellent, Ni{sup 2+}. To understand the molecular mechanisms underlying the induction of Tar activity by its ligands, the Escherichia coli Tar periplasmic domain with and without bound aspartate (Asp-Tar and apo-Tar, respectively) were each crystallized in two different forms. Using ammonium sulfate as a precipitant, crystals of apo-Tar1 and Asp-Tar1 were grown and diffracted to resolutions of 2.10 and 2.40 Å, respectively. Alternatively, using sodium chloride as a precipitant, crystals of apo-Tar2 and Asp-Tar2 were grown and diffracted to resolutions of 1.95 and 1.58 Å, respectively. Crystals of apo-Tar1 and Asp-Tar1 adopted space group P4{sub 1}2{sub 1}2, while those of apo-Tar2 and Asp-Tar2 adopted space groups P2{sub 1}2{sub 1}2{sub 1} and C2, respectively.

  8. The role of char and tar in determining the gas-phase partitioning of nitrogen during biomass gasification

    International Nuclear Information System (INIS)

    Broer, Karl M.; Brown, Robert C.

    2015-01-01

    Highlights: • Switchgrass was gasified at an equivalence ratio of zero and 650–850 °C. • Short residence times were employed to minimize secondary reactions. • Char- and tar-bound nitrogen, NH_3, HCN, and N_2 were all significant products. • Increasing temperature leads to increased release of gaseous nitrogen compounds. • Kinetic models of gasification should include nitrogen release from char and tar. - Abstract: Gasification is an attractive option for converting biomass into fuels and chemicals. Most biomass contains significant amounts of fuel-bound nitrogen (FBN), which partially converts into ammonia (NH_3) and hydrogen cyanide (HCN) during gasification. These nitrogen compounds are problematic as they can lead to NO_X emissions or catalyst poisoning in downstream applications of syngas. FBN can convert to other products as well, including diatomic nitrogen (N_2), char-bound nitrogen (char-N), and tar-bound nitrogen (tar-N). Efforts to predict concentrations of NH_3 and HCN have been hindered by a lack of accurate, comprehensive measurements of nitrogen partitioning among gasification products. The present study gasified switchgrass under allothermal, short residence time conditions and measured NH_3, HCN, char-N, and tar-N as a function of temperature in the range of 650–850 °C with diatomic nitrogen determined by difference. It was found that a major portion of FBN was retained in the char and tar products. As temperature was increased, char and tar were consumed, releasing nitrogen as gaseous NH_3 and HCN. This increase in undesirable nitrogen compounds is contrary to the predictions of most gasification models, which overlook the presence of significant nitrogen in char and tar even if they include tar cracking and char gasification reactions. The results of this study demonstrate that gas-phase reactions alone are not sufficient to predict the fate of nitrogen during gasification. In order for modeling efforts to obtain more accurate

  9. Potential contributions of asphalt and coal tar to black carbon quantification in urban dust, soils, and sediments

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Y.; Mahler, B.J.; Van Metre, P.C.; Ligouis, B.; Werth, C.J. [University of Illinois Urbana Champaign, Urbana, IL (USA). Dept. of Civil & Environmental Engineering

    2010-12-01

    Measurements of black carbon (BC) using either chemical or thermal oxidation methods are generally thought to indicate the amount of char and/or soot present in a sample. In urban environments, however, asphalt and coal-tar particles worn from pavement are ubiquitous and, because of their pyrogenic origin, could contribute to measurements of BC. Here we explored the effect of the presence of asphalt and coal-tar particles on the quantification of BC in a range of urban environmental sample types, and evaluated biases in the different methods used for quantifying BC. Samples evaluated were pavement dust, residential and commercial area soils, lake sediments from a small urban watershed, and reference materials of asphalt and coal tar. Total BC was quantified using chemical treatment through acid dichromate (Cr{sub 2}O{sub 7}) oxidation and chemo-thermal oxidation at 375{sup o}C (CTO-375). BC species, including soot and char/charcoal, asphalt, and coal tar, were quantified with organic petrographic analysis. Comparison of results by the two oxidation methods and organic petrography indicates that both coal tar and asphalt contribute to BC quantified by Cr{sub 2}O{sub 7} oxidation, and that coal tar contributes to BC quantified by CTO-375. These results are supported by treatment of asphalt and coal-tar reference samples with Cr2O7 oxidation and CTO-375. The reference asphalt is resistant to Cr{sub 2}O{sub 7} oxidation but not to CTO-375, and the reference coal tar is resistant to both Cr2O7 oxidation and CTO-375. These results indicate that coal tar and/or asphalt can contribute to BC measurements in samples from urban areas using Cr{sub 2}O{sub 7} oxidation or CTO-375, and caution is advised when interpreting BC measurements made with these methods.

  10. Numerical simulation studies of the groundwater discharge to streams from abandoned uranium mill tailings

    International Nuclear Information System (INIS)

    Abdul, A.S.; Gillham, R.W.

    1984-06-01

    This report presents an evaluation of the results of simulation studies of groundwater discharge to streams from abandoned uranium mill tailings and the effects of this discharge on the flux of contaminants to surface water systems. In particular, a discussion of the sensitivity of subsurface discharge to specific geometirc, climatic and hydrogeologic factors is presented. Simulations were carried out using a two-dimensional numerical finite-element unsaturated-saturated flow model. A total of twenty-six simulations were made. The first twenty-four of these considered a tailings medium with homogeneous and isotropic hydraulic properties and with textural properties similar to those of sandy geological materials. In addition, two simulations were carried out for tailings materials with hydraulic properties that are similar to those of silt-loam. The results indicated that the actual quantity of subsurface discharge depends on many factors including rainfall rate and duration, surface slope, and texture. However, for the medium-fine sand material, subsurface discharge was always a significant component of the total discharge. Within the context of uranium tailings management this implies that large quantities of contaminants from subsurface sources of medium-textured tailings can be expected to be discharged to streams during stormflow events. Therefore there is reason to suspect that untreated runoff from such tailings will contain significant concentrations of contaminants for long periods of time

  11. Volatilization of polycyclic aromatic hydrocarbons from coal-tar-sealed pavement.

    Science.gov (United States)

    Van Metre, Peter C; Majewski, Michael S; Mahler, Barbara J; Foreman, William T; Braun, Christopher L; Wilson, Jennifer T; Burbank, Teresa L

    2012-06-01

    Coal-tar-based pavement sealants, a major source of PAHs to urban water bodies, are a potential source of volatile PAHs to the atmosphere. An initial assessment of volatilization of PAHs from coal-tar-sealed pavement is presented here in which we measured summertime gas-phase PAH concentrations 0.03 m and 1.28 m above the pavement surface of seven sealed (six with coal-tar-based sealant and one with asphalt-based sealant) and three unsealed (two asphalt and one concrete) parking lots in central Texas. PAHs also were measured in parking lot dust. The geometric mean concentration of the sum of eight frequently detected PAHs (ΣPAH(8)) in the 0.03-m samples above sealed lots (1320 ng m(-3)) during the hottest part of the day was 20 times greater than that above unsealed lots (66.5 ng m(-3)). The geometric mean concentration in the 1.28-m samples above sealed lots (138 ng m(-3)) was five times greater than above unsealed lots (26.0 ng m(-3)). Estimated PAH flux from the sealed lots was 60 times greater than that from unsealed lots (geometric means of 88 and 1.4 μg m(-2) h(-1), respectively). Although the data set presented here is small, the much higher estimated fluxes from sealed pavement than from unsealed pavement indicate that coal-tar-based sealants are emitting PAHs to urban air at high rates compared to other paved surfaces. Published by Elsevier Ltd.

  12. UTILIZATION OF ACTIVATED ZEOLITE AS MOLECULAR SIEVE IN CHROMATOGRAPHIC COLUMN FOR SEPARATION OF COAL TAR COMPOUNDS

    Directory of Open Access Journals (Sweden)

    Dwi Retno Nurotul Wahidiyah

    2010-06-01

    Full Text Available Application of activated zeolite (ZAA as molecular sieve to separate compounds of coal tar from vaccum fractional distillation, have been done. The size of zeolite was 10-20 mesh and used as solid phase in column chromatography with length of 30 cm. The first step of the research was coal pyrolisis and the product (tar was distillated by fractional column and vaccum system at reduced pressure 44 cmHg and maximum temperature at 200 oC. The distillate from this procedure was flowed to the column chromatography of zeolite (ZAA. The compound absorbed by zeolite was eluted with varying solvents, i.e: CCl4, acetone and ethanol. Each fraction was then analyzed by gas chromatography. The results showed, zeolite have a capability to separate the compounds of tar and it tends to absorb medium hydrocarbon. The nonpolar eluent [CCl4] gives the better result in eluting tar compound than polar (ethanol or medium polar eluents (acetone.   Keywords: zeolite, coal tar, column chromatography

  13. Development of secondary chamber for tar cracking-improvement of wood pyrolysis performance in pre-vacuum chamber

    Science.gov (United States)

    Siahaan, S.; Homma, H.; Homma, H.

    2018-02-01

    Energy crisis and global warming, in other words, climate change are critical topics discussed in various parts of the world. Global warming primarily result from too much emission of carbon dioxide (CO2) in the atmosphere. To mitigate global warming, or climate change and improve electrification in rural areas, wood pyrolysis technology is developed in a laboratory scale, of which gases are directly applicable to the gas engine generator. Our laboratory has developed a prototype of wood pyrolysis plant with a pre-vacuum chamber. However, tar yield was around 40 wt% of feedstock. This research aims to reduce tar yield by secondary tar cracking. For the secondary tar cracking, a secondary pre-vacuum chamber is installed after primary pre-vacuum chamber. Gases generated in the primary pre-vacuum chamber are lead into the secondary chamber that is heated up to 1000 K. This paper reports performance of the secondary chamber for secondary tar cracking in homogeneous mode and heterogeneous mode with char.

  14. IDENTIFICATION OF SOME CARCINOGENIC POLYCYCLIC AROMATIC HYDROCARBONS IN BANGLADESHI VEHICLES EXHAUST TAR BY GAS CHROMATOGRAPHY-MASS SPECTROPHOTOMETER

    Directory of Open Access Journals (Sweden)

    M. Amzad Hossain

    2010-06-01

    Full Text Available A more sensitive GC-MS method has been established for the determination of some carcinogenic polycyclic aromatic hydrocarbons (PAHs in vehicles exhaust tar samples. The tar samples were extracted using dichloromethane (DMC: n-hexane solvent mixture. A multi-layer clean-up (silica gel/sodium sulphate column was used, followed by glass fiber filter (GFF paper. The method was successfully applied to determine a number of PAHs present in exhaust tar sample of different vehicles of the Atomic Energy Centre, Dhaka, Bangladesh.   Keywords: Carcinogenic polycyclic aromatic hydrocarbons, vehicles tar samples, identification, GC-MS/MS

  15. Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates.

    Science.gov (United States)

    Bryer, Pamela J; Scoggins, Mateo; McClintock, Nancy L

    2010-05-01

    Non-point-source pollution is a major source of ecological impairment in urban stream systems. Recent work suggests that coal-tar pavement sealants, used extensively to protect parking areas, may be contributing a large portion of the polycyclic aromatic hydrocarbon (PAH) loading seen in urban stream sediments. The hypothesis that dried coal-tar pavement sealant flake could alter the macroinvertebrate communities native to streams in Austin, TX was tested using a controlled outdoor laboratory type approach. The treatment groups were: control, low, medium, and high with total PAH concentrations (TPAH = sum of 16 EPA priority pollutant PAHs) of 0.1, 7.5, 18.4, & 300 mg/kg respectively. The low, medium, and high treatments were created via the addition of dried coal-tar pavement sealant to a sterile soil. At the start of the 24-day exposure, sediment from a minimally impacted local reference site containing a community of live sediment-dwelling benthic macroinvertebrates was added to each replicate. An exposure-dependent response was found for several stream health measures and for several individual taxa. There were community differences in abundance (P = 0.0004) and richness (P pavement sealants contain bioavailable PAHs that may harm aquatic environments. Copyright 2009 Elsevier Ltd. All rights reserved.

  16. Developing agricultural opportunities on mine tailings : the Green Mines green energy initiative

    Energy Technology Data Exchange (ETDEWEB)

    Tisch, B.; Spiers, G.; Beckett, P.; Lock, A. [Natural Resources Canada, Ottawa, ON (Canada). CANMET Mining and Mineral Sciences Laboratories

    2009-02-15

    The goal of the Green Mines green energy initiative is to advance mine reclamation through the beneficial use of organic residuals for the sustainable establishment of bioenergy crops and other productive land uses. Target organic residuals include: source separated organic compost; papermill biosolids; leaf and yard waste compost; and municipal wastewater biosolids. This presentation discussed the Green Mines green energy initiative with particular reference to potential uses; current participants; scope of the initiative; and progress to date. The presentation also discussed a column study that involved adding filter, filter fabric, silica sand and polyethylene beads to the base of columns. Unoxidized tailings were slurried and pumped into columns and then the oxidized tailings were dried and homogenized. The results of acidic copper/nickel tailings with lime and no lime were also discussed. A summary of findings from the column study was offered. It was found that nutrient management must be considered and organic covers appear to increase metal and arsenic leaching from unlimed tailings. The presentation also made reference to demonstration field plots; biosolids delivery; tilling; monitoring; biomass sampling; and harvesting. The presentation concluded with a discussion of next steps which involve completing construction of the current suite of field plots and implementing full monitoring. figs.

  17. Pelagic tar, dissolved/dispersed petroleum hydrocarbons and plastic distribution in the Cretan Sea, Greece

    Energy Technology Data Exchange (ETDEWEB)

    Kornilios, S.; Drakopoulos, P.G.; Dounas, C. [Institute of Marine Biology of Crete, Iraklio (Greece). Environmental Dept.

    1998-12-01

    During the first cruise of R/V `Philia` in July 1997 within the framework of the TALOS programme supported by the Greek Ministry of Physical Planning and Public Works, the sampling of floating tar, litter and sea water for dissolved/dispersed petroleum hydrocarbons (DDPH) was carried out in the Cretan Sea. Analysis of these data has allowed a first assessment of the status of floating marine pollution in the region. DDPH measurements showed a mean concentration of 0.145 {mu}g/l of chrysene equivalents (n = 24). Tar and plastics concentrations were in the range of 1-4280 and 0-1160 {mu}g/m{sup 2}, respectively. Mean pelagic tar concentration was 318 {mu}g/m{sup 2}, more than two times higher than what was reported for the area in previous studies. Based on in situ hydrographic observations there is strong evidence that most of the floating tar enters the Cretan Sea through the Ionian Sea. (author)

  18. Pelagic tar, dissolved/dispersed petroleum hydrocarbons and plastic distribution in the Cretan Sea, Greece

    Energy Technology Data Exchange (ETDEWEB)

    Kornilios, S.; Drakopoulos, P.G.; Dounas, C. [Institute of Marine Biology of Crete, Iraklio (Greece). Environmental Dept.

    1998-12-01

    During the first cruise of R/V 'Philia' in July 1997 within the framework of the TALOS programme supported by the Greek Ministry of Physical Planning and Public Works, the sampling of floating tar, litter and sea water for dissolved/dispersed petroleum hydrocarbons (DDPH) was carried out in the Cretan Sea. Analysis of these data has allowed a first assessment of the status of floating marine pollution in the region. DDPH measurements showed a mean concentration of 0.145 {mu}g/l of chrysene equivalents (n = 24). Tar and plastics concentrations were in the range of 1-4280 and 0-1160 {mu}g/m{sup 2}, respectively. Mean pelagic tar concentration was 318 {mu}g/m{sup 2}, more than two times higher than what was reported for the area in previous studies. Based on in situ hydrographic observations there is strong evidence that most of the floating tar enters the Cretan Sea through the Ionian Sea. (author)

  19. Pelagic tar, dissolved/dispersed petroleum hydrocarbons and plastic distribution in the Cretan Sea, Greece

    International Nuclear Information System (INIS)

    Kornilios, S.; Drakopoulos, P.G.; Dounas, C.

    1998-01-01

    During the first cruise of R/V 'Philia' in July 1997 within the framework of the TALOS programme supported by the Greek Ministry of Physical Planning and Public Works, the sampling of floating tar, litter and sea water for dissolved/dispersed petroleum hydrocarbons (DDPH) was carried out in the Cretan Sea. Analysis of these data has allowed a first assessment of the status of floating marine pollution in the region. DDPH measurements showed a mean concentration of 0.145 μg/l of chrysene equivalents (n = 24). Tar and plastics concentrations were in the range of 1-4280 and 0-1160 μg/m 2 , respectively. Mean pelagic tar concentration was 318 μg/m 2 , more than two times higher than what was reported for the area in previous studies. Based on in situ hydrographic observations there is strong evidence that most of the floating tar enters the Cretan Sea through the Ionian Sea. (author)

  20. A look at one of the world's largest apron feeder drives - Alberta Oil Sands Project

    Energy Technology Data Exchange (ETDEWEB)

    Persson, O. (Hagglunds Drives Canada Inc., Vancouver, BC (Canada))

    1999-01-01

    Various types of equipment to transport tar sands to processing plants are discussed, with special attention to the advantages of hydraulic direct drives over conventional electro-mechanical drives. A hydraulic direct drive such as the Hagglund Drive has exceptional starting torque capacity due to the high torque capability of the hydraulic motor. As such, it can be particularly useful in applications where shock loads occur with some frequency, or where many starts and stops are needed. Application of the Hagglund drive to power one of the world's largest apron feeders in the Alberta Oil Sands is described as an illustration of the exceptional reliability, productivity and performance of this equipment. It has about one five-hundredth of the inertia of an equivalent high speed drive with gear reducer, a feature which is particularly significant in the case of feeders which are known to suffer much downtime due to chain related problems. These types of drives have also been used to great advantage in the process industries like pulp and paper, chemical, rubber and plastics, recycling and steel. 1 tab., 1 fig.

  1. 77 FR 48431 - Safety Zone for Fireworks Display, Pamlico and Tar Rivers; Washington, NC

    Science.gov (United States)

    2012-08-14

    ... near the Pamlico and Tar Rivers to commemorate Beaufort County's 300th anniversary. The temporary... 1625-AA00 Safety Zone for Fireworks Display, Pamlico and Tar Rivers; Washington, NC AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone on...

  2. Long vigil in Athabasca oil sands culminates in rapid expansion plans

    Energy Technology Data Exchange (ETDEWEB)

    1974-05-01

    Great Canadian Oil Sands Ltd. needs to earn $40 million or more per year to get a reasonable return on the investment, vice president and general manager R.D. Humphreys told delegates at the Petroleum Accountants Society of W. Canada annual conference at Jasper Park Lodge. The conference then was ''the Alberta Oil Sands.'' Sun Oil Co. has taken no return yet, but has paid off the loans and taken shares in return so it owns nearly all the equity capital. The operation is not really breaking even at present, but should improve because GCOS is getting the full effect of the oil price increase under the original royalty agreement with the Alberta government. It is hoped that this will enable the company to recoup an accumulated deficit of more than $90 million. Money is the biggest problem for the current expansion designed to raise production to the authorized 65,000 bpd. Manpower is second and delivery of materials third. There is a lead time of 15 to 18 mo. on critical materials. Over the long term, tailings disposal is the greatest single problem facing all oil sands operators.

  3. Evaluation of liners for a uranium-mill tailings disposal site: a status report

    International Nuclear Information System (INIS)

    Buelt, J.L.; Hale, V.Q.; Barnes, S.M.; Silviera, D.J.

    1981-05-01

    The United States Department of Energy is conducting a program designed to reclaim or stabilize inactive uranium-mill tailings sites. This report presents the status of the Liner Evaluation Program. The purpose of the study was to identify eight prospective lining materials or composites for laboratory testing. The evaluation was performed by 1) reviewing proposed regulatory requirements to define the material performance criteria; 2) reviewing published literature and communicating with industrial and government experts experienced with lining materials and techniques; and 3) characterizing the tailings at three of the sites for calcium concentration, a selection of anions, radionuclides, organic solvents, and acidity levels. The eight materials selected for laboratory testing are: natural soil amended with sodium-saturated montmorillonite (Volclay); locally available clay in conjunction with an asphalt emulsion radon suppression cover; locally available clay in conjunction with a multibarrier radon suppression cover; rubberized asphalt membrane; hydraulic asphalt concrete; chlorosulfonated polyethylene (hypalon) or high-density polyethylene; bentonite, sand and gravel mixture; and catalytic airblown asphalt membrane. The materials will be exposed in test units now being constructed to conditions such as wet/dry cycles, temperature cycles, oxidative environments, ion-exchange elements, etc. The results of the tests will identify the best material for field study. The status report also presents the information gathered during the field studies at Grand Junction, Colorado. Two liners, a bentonite, sand and gravel mixture, and a catalytic airblown asphalt membrane, were installed in a prepared trench and covered with tailings. The liners were instrumented and are being monitored for migration of moisture, radionuclides, and hazardous chemicals. The two liner materials will also be subjected to accelerated laboratory tests for a comparative assessment

  4. Selected constituents in the smokes of U. S. commercial cigaretts: tar, nicotine, carbon monoxide and carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, R.A.; Quincy, R.B.; Guerin, M.R.

    1979-05-01

    One hundred twenty-one brands of United States commercial cigarettes were analyzed for their deliveries of tar, nicotine, carbon monoxide, and carbon dioxide under standard analytical smoking conditions. The sample included both filter and nonfilter cigarettes. Comparisons of carbon monoxide deliveries over the range of observed tar deliveries indicated a very high correlation between CO and tar for filter cigarettes, but nonfilter cigarettes tended to produce much less CO than would have been predicted from their tar deliveries. Comparison of ORNL nicotine values for specific brands with those determined by the Federal Trade Commission yield no statistically significant differences between laboratories. 4 figures, 6 tables.

  5. Some studies on tar pillets at Veraval coast (Gujarat)

    Digital Repository Service at National Institute of Oceanography (India)

    Kadam, A.N.

    Infrared spectroscopic (IR) analysis indicated that the tar pillets contain saturated hydrocarbons particularly higher homologues of n-paraffins, unsaturated and carbonyl type of polar compounds. Gas chromatographic (GLC) fingerprint pattern...

  6. Hydrogen production from biomass tar by catalytic steam reforming

    International Nuclear Information System (INIS)

    Yoon, Sang Jun; Choi, Young-Chan; Lee, Jae-Goo

    2010-01-01

    The catalytic steam reforming of model biomass tar, toluene being a major component, was performed at various conditions of temperature, steam injection rate, catalyst size, and space time. Two kinds of nickel-based commercial catalyst, the Katalco 46-3Q and the Katalco 46-6Q, were evaluated and compared with dolomite catalyst. Production of hydrogen generally increased with reaction temperature, steam injection rate and space time and decreased with catalyst size. In particular, zirconia-promoted nickel-based catalyst, Katalco 46-6Q, showed a higher tar conversion efficiency and shows 100% conversion even relatively lower temperature conditions of 600 deg. C. Apparent activation energy was estimated to 94 and 57 kJ/mol for dolomite and nickel-based catalyst respectively.

  7. Tail posture predicts tail damage among weaned piglets

    NARCIS (Netherlands)

    Zonderland, J.J.; Riel, van J.W.; Bracke, M.B.M.; Kemp, B.; Hartog, den L.A.; Spoolder, H.A.M.

    2009-01-01

    Tail biting in pigs is a widespread behavioural vice with significant animal welfare and economic consequences. All too often, tail biting is not diagnosed nor dealt with until tail damage is present. To effectively reduce the negative effects of tail biting, it must be diagnosed in an early stage.

  8. Royal Society of Canada expert panel report : environmental and health impacts of Canada's oil sands industry

    International Nuclear Information System (INIS)

    Gosselin, P.; Hrudey, S.E.; Naeth, M.A.; Plourde, A.; Therrien, R.; Laval Univ., Quebec City, PQ; Van Der Kraak, G.; Guelph Univ., ON; Xu, Z.

    2010-12-01

    This expert panel report was commissioned by the Royal Society of Canada to provide a comprehensive evidence-based assessment of the environmental and health impacts of Canada's oil sands industry. The report evaluated the feasibility of land reclamation and the impacts of oil sands contaminants on downstream residents. Health impacts on residents living in the Regional Municipality of Wood Buffalo were assessed, and the impacts on regional water supplies were evaluated. Regional water and ground water quantities were examined, and issues related to tailing pond operations and reclamation were examined. Ambient air quality impacts were assessed, as well as potential impacts of the oil sands industry on greenhouse gas (GHG) emissions. The environmental regulatory performance of operators in the industry was also evaluated. A summary of economic and policy issues related to the industry was also provided. The study identified major gaps in the process of assessment, prevention, and mitigation of the health impacts of oil sands exploitation, as as major indirect health impacts linked to past exploitation activities. 672 refs., 11 tabs., 11 figs. 10 appendices.

  9. Environmental Impacts of Sand Exploitation. Analysis of Sand Market

    Directory of Open Access Journals (Sweden)

    Marius Dan Gavriletea

    2017-06-01

    Full Text Available Sand is an indispensable natural resource for any society. Despite society’s increasing dependence on sand, there are major challenges that this industry needs to deal with: limited sand resources, illegal mining, and environmental impact of sand mining. The purpose of this paper is twofold: to present an overview of the sand market, highlighting the main trends and actors for production, export and import, and to review the main environmental impacts associated with sand exploitation process. Based on these findings, we recommend different measures to be followed to reduce negative impacts. Sand mining should be done in a way that limits environmental damage during exploitation and restores the land after mining operations are completed.

  10. Luminescence monitoring of oil or tar contamination for industrial hygiene

    International Nuclear Information System (INIS)

    Gammage, R.B.; Vo-Dinh, T.

    1980-01-01

    Synfuel plants produce potentially carcinogenic oils and tars. Exposure of workers to these tars and oils is difficult to avoid completely and occurs via direct contact with dirty surfaces or condensation of escaped fumes onto or within the body. Surface skin, measurements are made directly with a near-ultraviolet luminoscope employing a fiber optics lightguide and a stethoscopic cap pressed against the skin. This instrument is especially suitable for measuring ng to μg/cm 2 amounts of residual contamination remaining on the surface of the skin after washing. To minimize the potential for carcinogenicity, the excitating ultraviolet light intensity is only 1/100th that of sunlight. (orig.)

  11. Effects of electric current upon catalytic steam reforming of biomass gasification tar model compounds to syngas

    International Nuclear Information System (INIS)

    Tao, Jun; Lu, Qiang; Dong, Changqing; Du, Xiaoze; Dahlquist, Erik

    2015-01-01

    Highlights: • ECR technique was proposed to convert biomass gasification tar model compounds. • Electric current enhanced the reforming efficiency remarkably. • The highest toluene conversion reached 99.9%. • Ni–CeO 2 /γ-Al 2 O 3 exhibited good stability during the ECR performance. - Abstract: Electrochemical catalytic reforming (ECR) technique, known as electric current enhanced catalytic reforming technique, was proposed to convert the biomass gasification tar into syngas. In this study, Ni–CeO 2 /γ-Al 2 O 3 catalyst was prepared, and toluene was employed as the major feedstock for ECR experiments using a fixed-bed lab-scale setup where thermal electrons could be generated and provided to the catalyst. Several factors, including the electric current intensity, reaction temperature and steam/carbon (S/C) ratio, were investigated to reveal their effects on the conversion of toluene as well as the composition of the gas products. Moreover, toluene, two other tar model compounds (benzene and 1-methylnaphthalene) and real tar (tar-containing wastewater) were subjected to the long period catalytic stability tests. All the used catalysts were analyzed to determine their carbon contents. The results indicated that the presence of electric current enhanced the catalytic performance remarkably. The toluene conversion reached 99.9% under the electric current of 4 A, catalytic temperature of 800 °C and S/C ratio of 3. Stable conversion performances of benzene, 1-methylnaphthalene and tar-containing wastewater were also observed in the ECR process. H 2 and CO were the major gas products, while CO 2 and CH 4 were the minor ones. Due to the promising capability, the ECR technique deserves further investigation and application for efficient tar conversion

  12. Application of forward osmosis membrane technology for oil sands process-affected water desalination.

    Science.gov (United States)

    Jiang, Yaxin; Liang, Jiaming; Liu, Yang

    2016-01-01

    The extraction process used to obtain bitumen from the oil sands produces large volumes of oil sands process-affected water (OSPW). As a newly emerging desalination technology, forward osmosis (FO) has shown great promise in saving electrical power requirements, increasing water recovery, and minimizing brine discharge. With the support of this funding, a FO system was constructed using a cellulose triacetate FO membrane to test the feasibility of OSPW desalination and contaminant removal. The FO systems were optimized using different types and concentrations of draw solution. The FO system using 4 M NH4HCO3 as a draw solution achieved 85% water recovery from OSPW, and 80 to 100% contaminant rejection for most metals and ions. A water backwash cleaning method was applied to clean the fouled membrane, and the cleaned membrane achieved 77% water recovery, a performance comparable to that of new FO membranes. This suggests that the membrane fouling was reversible. The FO system developed in this project provides a novel and energy efficient strategy to remediate the tailings waters generated by oil sands bitumen extraction and processing.

  13. Pyrolysis kinetics of phenols from lignite semicoking tar

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Polovetskaya, O.S.; Proskuryakov, V.A.; Shavyrina, O.A. [Leo Tolstoy Tula State Pedag University, Tula (Russian Federation)

    2002-11-01

    The features of pyrolysis of phenols from lignite semicoking tar were studied. The activation energy and order of the reactions of accumulation of methane, hydrogen, carbon monoxide and dioxide, naphthalene and its methyl homologs, phenols, and isomeric cresols and dimethylphenols were determined.

  14. Pyrolysis of aseptic packages (tetrapak) in a laboratory screw type reactor and secondary thermal/catalytic tar decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Haydary, J., E-mail: juma.haydary@stuba.sk [Institute of Chemical and Environmental Engineering, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, 812 37 Bratislava (Slovakia); Susa, D.; Dudáš, J. [Institute of Chemical and Environmental Engineering, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, 812 37 Bratislava (Slovakia)

    2013-05-15

    Highlights: ► Pyrolysis of aseptic packages was carried out in a laboratory flow reactor. ► Distribution of tetrapak into the product yields was obtained. ► Composition of the pyrolysis products was estimated. ► Secondary thermal and catalytic decomposition of tars was studied. ► Two types of catalysts (dolomite and red clay marked AFRC) were used. - Abstract: Pyrolysis of aseptic packages (tetrapak cartons) in a laboratory apparatus using a flow screw type reactor and a secondary catalytic reactor for tar cracking was studied. The pyrolysis experiments were realized at temperatures ranging from 650 °C to 850 °C aimed at maximizing of the amount of the gas product and reducing its tar content. Distribution of tetrapak into the product yields at different conditions was obtained. The presence of H{sub 2}, CO, CH{sub 4}, CO{sub 2} and light hydrocarbons, HCx, in the gas product was observed. The Aluminum foil was easily separated from the solid product. The rest part of char was characterized by proximate and elemental analysis and calorimetric measurements. The total organic carbon in the tar product was estimated by elemental analysis of tars. Two types of catalysts (dolomite and red clay marked AFRC) were used for catalytic thermal tar decomposition. Three series of experiments (without catalyst in a secondary cracking reactor, with dolomite and with AFRC) at temperatures of 650, 700, 750, 800 and 850 °C were carried out. Both types of catalysts have significantly affected the content of tars and other components in pyrolytic gases. The effect of catalyst on the tetrapack distribution into the product yield on the composition of gas and on the total organic carbon in the tar product is presented in this work.

  15. Analysis of disposal of uranium mill tailings in a mined out open pit

    International Nuclear Information System (INIS)

    Staub, W.P.; Triegel, E.K.

    1978-08-01

    Mined out open pits are presently under consideration as disposal sites for uranium mill tailings. In this method of tailings management, the escape of contaminated liquid into an adjacent aquifer is the principal environmental concern. The modified Bishop Method was used to analyze the structural stability of a clay liner along the highwall and fluid flow models were used to analyze the effect of tailings solutions on groundwater under several operating conditions. The slope stability of a clay liner was analyzed at three stages of operation: (1) near the beginning of construction, (2) when the pit is partially filled with tailings, and (3) at the end of construction. Both clay lined and unlined pits were considered in the fluid flow modeling. Finally, the seepage of tailings solutions through the clay liner was analyzed. Results of the slope stability analysis showed that it would be necessary to construct the clay liner as a modified form of engineered embankment. This embankment would be similar in construction to that of an earthfill dam. It could be constructed on a 1 : 1 slope provided the tailings slurry were managed properly. It would be necessary to maintain the freeboard height between the embankment and tailings at less than 4 m. A partially dewatered sand beach would have to be located adjacent to the embankment. Potential leakage and aquifer contamination was modeled for lined and unlined pits of various designs. Sulfate, and possibly U and Th, are the most likely contaminants. Results from the model showed the clay and soil cement lined pit to be most effective in containing the pollutants

  16. Machine-smoking studies of cigarette filter color to estimate tar yield by visual assessment and through the use of a colorimeter.

    Science.gov (United States)

    Morton, Michael J; Williams, David L; Hjorth, Heather B; Smith, Jennifer H

    2010-04-01

    This paper explores using the intensity of the stain on the end of the filter ("filter color") as a vehicle for estimating cigarette tar yield, both by instrument reading of the filter color and by visual comparison to a template. The correlation of machine-measured tar yield to filter color measured with a colorimeter was reasonably strong and was relatively unaffected by different puff volumes or different tobacco moistures. However, the correlation of filter color to machine-measured nicotine yield was affected by the moisture content of the cigarette. Filter color, as measured by a colorimeter, was generally comparable to filter extraction of either nicotine or solanesol in its correlation to machine-smoked tar yields. It was found that the color of the tar stain changes over time. Panelists could generally correctly order the filters from machine-smoked cigarettes by tar yield using the intensity of the tar stain. However, there was considerable variation in the panelist-to-panelist tar yield estimates. The wide person-to-person variation in tar yield estimates, and other factors discussed in the text could severely limit the usefulness and practicality of this approach for visually estimating the tar yield of machine-smoked cigarettes. Copyright 2009 Elsevier Inc. All rights reserved.

  17. Fungal cultures of tar bush and creosote bush for production of two phenolic antioxidants (pyrocatechol and gallic acid).

    Science.gov (United States)

    Ventura, J; Gutiérrez-Sanchez, G; Rodríguez-Herrera, R; Aguilar, C N

    2009-01-01

    'Tar bush' and 'creosote bush' were substrates of fungal cultivation for tannase production and gallic acid and pyrocatechol accumulation. Aspergillus niger GH1 grew similarly on both plant materials under solid state culture conditions, reaching maximal levels after 4 d. Fungal strain degraded all tannin content of creosote bush after 4 d of fermentation and >75 % of tar bush after 5 d. Higher level of tannase activity was detected in tar bush fermentation. Biotransformation of tannins to gallic acid was high (93 % in creosote bush and 89 % in tar bush). Pyrocatechol was released poorly. Kinetic parameters of tannin conversion were calculated.

  18. Family physicians and youth tobacco-free education: outcomes of the Colorado Tar Wars program.

    Science.gov (United States)

    Cain, Jeffrey J; Dickinson, W Perry; Fernald, Douglas; Bublitz, Caroline; Dickinson, L Miriam; West, David

    2006-01-01

    Tar Wars is a national school-based tobacco-free education program operated by the American Academy of Family Physicians. The Tar Wars lesson uses an interactive 45-min session taught by volunteer family physicians in 4th- and 5th-grade classrooms and focuses on the short-term image-based consequences of tobacco use. In this study, we evaluated the effectiveness of the Tar Wars program in Colorado with both quantitative and qualitative measures. Students participating in the quantitative evaluation were tested before and after a Tar Wars teaching session using a 14-question test covering the short-term and image-based consequences of tobacco use, cost of smoking, tobacco advertising, and social norms of tobacco use. Qualitative evaluation of the program included guided telephone interviews and focus groups with participating students, teachers, and presenters. Quantitative evaluation showed statistically significant improvement in correct responses for the 14 questions measured with an average increase in correct responses from 8.95 to 10.23. Three areas recommended by the Centers for Disease Control (CDC) for youth tobacco prevention showed greater change in correct responses, including cost of smoking, truth of tobacco advertising, and peer norms of tobacco use. Qualitative evaluation found that the overall message of the session was well received, that previously known tobacco information was reinforced by its presentation in a novel format, and that new information learned included cost of smoking, truth of tobacco advertising, and peer norms of tobacco use. The Tar Wars lesson plan is effective in increasing students' understanding about the short-term consequences of tobacco use, cost of tobacco use, truth of tobacco advertising, and peer norms. Tar Wars meets the CDC guidelines as one component of effective comprehensive youth tobacco prevention.

  19. No Increased Risk of Cancer after Coal Tar Treatment in Patients with Psoriasis or Eczema

    NARCIS (Netherlands)

    Roelofzen, Judith H. J.; Aben, Katja K. H.; Oldenhof, Ursula T. H.; Coenraads, Pieter-Jan; Alkemade, Hans A.; van de Kerkhof, Peter C. M.; van der Valk, Pieter G. M.; Kiemeney, Lambertus A. L. M.

    Coal tar is an effective treatment for psoriasis and eczema, but it contains several carcinogenic compounds. Occupational and animal studies have shown an increased risk of cancer after exposure to coal tar. Many dermatologists have abandoned this treatment for safety reasons, although the risk of

  20. Tar removal from biomass derived fuel gas by pulsed corona discharges: chemical kinetic study II

    NARCIS (Netherlands)

    Nair, S.A.; Yan, K.; Pemen, A.J.M.; Heesch, van E.J.M.; Ptasinski, K.J.; Drinkenburg, A.A.H.

    2005-01-01

    Tar (heavy hydrocarbon or poly aromatic hydrocarbon (PAH)) removal from biomass derived fuel gas is one of the biggest obstacles in its utilization for power generation. We have investigated pulsed corona as a method for tar removal. Our previous experimental results indicate the energy consumption

  1. Abating coal tar seepage into surface water bodies using sheet piles with sealed interlocks

    International Nuclear Information System (INIS)

    Collingwood, B.I.; Boscardin, M.D.; Murdock, R.F.

    1995-01-01

    A former coal tar processing facility processed crude coal tar supplied from manufactured gas plants in the area. Coal-tar-contaminated ground water from the site was observed seeping through an existing timber bulkhead along a tidal river and producing a multicolored sheen on the surface of the river. As part of a short-term measure to abate the seepage into the river, 64-m long anchored sheet pile wall with sheet pile wing walls at each end was constructed inland of the of the timber bulkhead. The sheet piles extended to low-permeability soils at depth and the interlocks of the sheet piles were provided with polyurethane rubber seals. Based on postconstruction observations for leakage and sheens related to leakage, the steel sheet piles with polyurethane rubber interlock seals appeared to provide a successful seal and abate coal-tar-contaminated ground water seepage into the river. The tie rod penetration sealing proved to be a more problematic detail, but through several postconstruction grouting episodes, an effective seal was produced

  2. Effect of the rate of heating on the quality of the primary tar in low-temperature coal-carbonization process

    Energy Technology Data Exchange (ETDEWEB)

    Turskii, Y I

    1956-01-01

    Two stages are observed. The first stage yields products of the primary and partial decomposition of coal, mainly water, CO/sub 2/, and CO as decomposition products of functional groups (-COOH, > CO, - OH, and so forth). No tar is formed in this stage. The structural decomposition and tar formation occur in the second stage. The rate of heating is important for the quality of the tar obtained. The slow rate of heating with both stages following each other yields a good-quality tar, richer in C and H, with lower O content. In case of high rate of heating both stages overlap. The tar is of poorer quality with higher specific gravity, and contains more O and asphaltenes. The complete experimental data are given in detail.

  3. Manufacturing of glass from tin mining tailings in Bolivia

    International Nuclear Information System (INIS)

    Arancibia, J. r. H.; Alfonso, P.; Garcia-Valles, M.; Martinez, S.; Parcerisa, D.; Canet, C.; Romero, F. M.

    2013-01-01

    Tailings from mining activities in Bolivia represent an environmental problem. In the vicinity of the tin mines of Llallagua, Potosi department, there are large dumps and tailings. We present a study of the use of these wastes as raw materials for the manufacture of glass. This procedure aims to contribute to environmental remediation of mining areas through the vitrification, a process which offers an alternative for stabilization of hazardous waste. In addition, the marketing of the obtained product would provide an additional income to the mining areas. For this study three samples of mining waste, with grain size between sand and silt, were used. The chemical composition of these raw materials, determined by X-ray fluorescence, is granitic, with high contents of heavy metals. On the basis of its composition, glass were made from silica glass by adding CaCO 3 and Na 2 CO 3 . The thermal cycle has been determined from TDA. Tg values of glass range from 626 degree centigrade to 709 degree centigrade. Leaching tests of the obtained glasses confirm their capacity to retain heavy metals. (Author)

  4. BTX production by in-situ contact reforming of low-temperature tar from coal with zeolite-derived catalysts; Zeolite kei shokubai wo mochiita sekitan teion tar no sesshoku kaishitsu ni yoru BTX no seisei

    Energy Technology Data Exchange (ETDEWEB)

    Matsunaga, T.; Fuda, K.; Murakami, K.; Kyo, M.; Hosoya, S.; Kobayashi, S. [Akita University, Akita (Japan). Mining College

    1996-10-28

    On BTX production process from low-temperature tar obtained by pyrolysis of coal, the effect of exchanged metallic species and reaction temperature were studied using metallic ion-exchanged Y-zeolite as catalyst. In experiment, three kinds of coals with different produced tar structures such as Taiheiyo and PSOC-830 sub-bituminous coals and Loy Yang brown coal were used. Y-zeolite ion-exchanged with metal chloride aqueous solution was used as catalyst. Zn{sup 2+}, Ni{sup 2+} and In{sup 3+} were used as metal ions to be exchanged. The experiment was conducted by heating a pyrolysis section up to 600{degree}C for one hour after preheating a contact reforming section up to a certain proper temperature. As a result, the Ni system catalyst was effective for BTX production from aromatic-abundant tar, while the Zn system one from lower aromatic tar. In general, relatively high yields of toluene and xylene were obtained at lower temperature, while those of benzene at higher temperature. 4 figs., 1 tab.

  5. Evidence for conformational flexibility in the Tat-TAR recognition motif of cyclin T1

    International Nuclear Information System (INIS)

    Das, Chandreyee; Edgcomb, Stephen P.; Peteranderl, Ralph; Chen, Lily; Frankel, Alan D.

    2004-01-01

    Cyclin T1 (CycT1) is a cellular transcription elongation factor that also participates in Tat-mediated activation of several lentiviral promoters. In human immunodeficiency virus (HIV), CycT1 is required for Tat to bind tightly to TAR and interacts in the ternary complex via its Tat-TAR recognition motif (TRM). In the related bovine immunodeficiency virus (BIV), Tat recognizes its cognate TAR element with high affinity and specificity in the absence of CycT1. At both promoters, CycT1 recruits the Cdk9 kinase, which phosphorylates RNA polymerase II to generate processive transcription complexes. To examine the physical properties of CycT1, we purified a functional domain corresponding to residues 1-272 and found that it possesses a stably folded core, as judged by partial proteolysis and circular dichroism experiments. Interestingly, the C-terminal 20 residues corresponding to the TRM appear conformationally flexible or disordered. The TRM of the bovine CycT1 (bCycT1) is similarly sensitive to proteolysis yet differs in sequence from the human protein. In particular, bCycT1 lacks a cysteine at residue 261 known to be critical for HIV but not BIV ternary complex formation, and mutagenesis data are consistent with a proposed role for this cysteine in metal binding. The apparent flexibility of the TRM suggests that conformational rearrangements may accompany formation of CycT1-Tat-TAR ternary complexes and may contribute to different TAR recognition strategies in different lentiviruses

  6. Numerical simulation of vortex pyrolysis reactors for condensable tar production from biomass

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R.S.; Bellan, J. [California Inst. of Tech., Pasadena, CA (United States). Jet Propulsion Lab.

    1998-08-01

    A numerical study is performed in order to evaluate the performance and optimal operating conditions of vortex pyrolysis reactors used for condensable tar production from biomass. A detailed mathematical model of porous biomass particle pyrolysis is coupled with a compressible Reynolds stress transport model for the turbulent reactor swirling flow. An initial evaluation of particle dimensionality effects is made through comparisons of single- (1D) and multi-dimensional particle simulations and reveals that the 1D particle model results in conservative estimates for total pyrolysis conversion times and tar collection. The observed deviations are due predominantly to geometry effects while directional effects from thermal conductivity and permeability variations are relatively small. Rapid ablative particle heating rates are attributed to a mechanical fragmentation of the biomass particles that is modeled using a critical porosity for matrix breakup. Optimal thermal conditions for tar production are observed for 900 K. Effects of biomass identity, particle size distribution, and reactor geometry and scale are discussed.

  7. Analysis of the use of coal tar as a binder in bituminous mixtures, using Marshall and Ramcodes methodologies

    International Nuclear Information System (INIS)

    Ochoa-Díaz, R

    2013-01-01

    This paper presents an alternative use of coal tar, a by-product of the steel industry, given the problems of accumulation and negative environmental impact. Therefore, it is necessary to analyze the incorporation of coal tar as a binder in paving mixtures. First, this paper presents the origin, description of the main characteristics, and properties of tar. Then, this paper evaluates the mix of coal tar by means of the RAMCODES and Marshall methodologies to determine its resistance. The results of the tests explain the physical and mechanical properties of the mix. Taking into account the results of both methods, this paper makes a comparison to determine the suitability of the RAMCODES methodology in the mix design. Finally, it analyzes the alternatives to coal tar that can be used as binders in bituminous mixes for pavement and the advantages of their uses under some specific conditions

  8. Quantitative analysis of phenol and alkylphenols in Brazilian coal tar

    Directory of Open Access Journals (Sweden)

    Elina Bastos Caramão

    2004-04-01

    Full Text Available The main purpose of this work is the identification and quantification of phenolic compounds in coal tar samples from a ceramics factory in Cocal (SC, Brazil. The samples were subjected to preparative scale liquid chromatography, using Amberlyst A-27TM ion-exchange resin as stationary phase. The fractions obtained were classified as "acids" and "BN" (bases and neutrals. The identification and quantification of phenols, in the acid fraction, was made by gas chromatography coupled to mass spectrometry (GC/MS. Nearly twenty-five phenols were identified in the samples and nine of them were also quantified. The results showed that coal tar has large quantities of phenolic compounds of industrial interest.

  9. Understanding the fate and transport of petroleum hydrocarbons from coal tar within gasholders.

    Science.gov (United States)

    Coulon, Frédéric; Orsi, Roberto; Turner, Claire; Walton, Chris; Daly, Paddy; Pollard, Simon J T

    2009-02-01

    Coal tars have been identified as posing a threat to human health due to their toxic, mutagenic and carcinogenic characteristics. Workers involved in former gasholders decommissioning are potentially exposed to relevant concentrations of volatile and semi-volatile hydrocarbons upon opening up derelict tanks and during tar excavation/removal. While information on contaminated sites air-quality and its implications on medium-long term exposure is available, acute exposure issues associated with the execution of critical tasks are less understood. Calculations indicated that the concentration of a given contaminant in the gasholder vapour phase only depends on the coal tar composition, being only barely affected by the presence of water in the gasholder and the tar volume/void space ratio. Fugacity modelling suggested that risk-critical compounds such as benzene, naphthalene and other monocyclic and polycyclic aromatic hydrocarbons may gather in the gasholder air phase at significant concentrations. Gasholder emissions were measured on-site and compared with the workplace exposure limits (WELs) currently in use in UK. While levels for most of the toxic compounds were far lower than WELs, benzene air-concentrations where found to be above the accepted threshold. In addition due to the long exposure periods involved in gasholder decommissioning and the significant contribution given by naphthalene to the total coal tar vapour concentration, the adoption of a WEL for naphthalene may need to be considered to support operators in preventing human health risk at the workplace. The Level I fugacity approach used in this study demonstrated its suitability for applications to sealed environments such as gasholders and its further refining could provide a useful tool for land remediation risk assessors.

  10. DeepMirTar: a deep-learning approach for predicting human miRNA targets.

    Science.gov (United States)

    Wen, Ming; Cong, Peisheng; Zhang, Zhimin; Lu, Hongmei; Li, Tonghua

    2018-06-01

    MicroRNAs (miRNAs) are small noncoding RNAs that function in RNA silencing and post-transcriptional regulation of gene expression by targeting messenger RNAs (mRNAs). Because the underlying mechanisms associated with miRNA binding to mRNA are not fully understood, a major challenge of miRNA studies involves the identification of miRNA-target sites on mRNA. In silico prediction of miRNA-target sites can expedite costly and time-consuming experimental work by providing the most promising miRNA-target-site candidates. In this study, we reported the design and implementation of DeepMirTar, a deep-learning-based approach for accurately predicting human miRNA targets at the site level. The predicted miRNA-target sites are those having canonical or non-canonical seed, and features, including high-level expert-designed, low-level expert-designed, and raw-data-level, were used to represent the miRNA-target site. Comparison with other state-of-the-art machine-learning methods and existing miRNA-target-prediction tools indicated that DeepMirTar improved overall predictive performance. DeepMirTar is freely available at https://github.com/Bjoux2/DeepMirTar_SdA. lith@tongji.edu.cn, hongmeilu@csu.edu.cn. Supplementary data are available at Bioinformatics online.

  11. Seasonal and spatial trends in production and stable isotope signatures of primary producers in Alberta oil sands reclamation wetlands

    International Nuclear Information System (INIS)

    Boutsivongsakd, M; Chen, H.; Legg, A.; Farwell, A.; Dixon, G.

    2010-01-01

    Oil sands processing produces large amounts of waste water that contains polycyclic aromatic hydrocarbons (PAHs) and naphthenic acids (NAs). This study investigated the effects of exposure to PAHs and NA in aquatic organisms. The carbon and nitrogen dynamics in primary producers using stable isotopes in process-affected and reference wetlands were studied. Plankton and periphytic samples from artificial wetland substrates were collected and analyzed. Periphyton was collected in 14 to 20 day intervals for 5 different time periods in 2007 and 2008 in order to analyze seasonal trends in isotopic composition. Results of the study showed d15N enriched values for some consolidated tailings (CT) at sites in 2008. Other sites with mature fine tailings (MFT) as well as non-MFT sites did not have enriched d15N values. The study suggested that there are variations in ammonia levels in the CTs of different oil sands operators. Differences in the quality of the CT resulted in differences in d15N values of the periphyton-dominated by algae as well as in the periphyton dominated by microbes.

  12. The growth and photosynthesis of Typha in oil sands process affected material and water

    Energy Technology Data Exchange (ETDEWEB)

    Foote, L. [Alberta Univ., Edmonton, AB (Canada); Hornung, J. [Petro-Canada, Calgary, AB (Canada)

    2007-07-01

    Aquatic plants such as cattail contribute substantially to the energy flow in wetlands. Since Typha (cattail) plants acquire and cycle carbon and nutrients through wetlands, their growth and recycling of captured nutrients are an important part of natural, healthy wetland ecosystems. Cattail are pervasive and satisfy many of the criteria to be used as indicators of wetland integrity. This study investigated if cattail growth and carbon accrual were influenced by oil sands process materials (OSPM) such as consolidated tailings (CT). The purpose was to facilitate land reclamation initiatives by evaluating the impact that constituents of oil sands process material have on aquatic plant growth. The study was conducted at Suncor's experimental trenches. Six lined basins were used, of which 3 were filled with natural water and 3 were filled with trench water. Cattail were planted in different growth medium combinations, including CT over CT; soil over soil; soil over CT; and soil over sterilized sand. All leaf lengths and widths were measured along with the photosynthesis of the leaves and root and plant biomass at planting and after 2-years growth. A larger leaf area was observed under oil sands process influence, which may indicate increased carbon accrual above ground. Leaf area data suggested that CT affected plants are quite productive. The study also indicated that oil sands affected water may reduce plant fitness, and therefore could influence the overall oil sands reclamation timelines. Conversely, cattail grown in soil capped process affected material had a much larger leaf area compared to those grown in soil capped sand, most likely due to the higher levels of ammonia in process affected material.

  13. Source identification of a tar residue from Mumbai Beach

    Digital Repository Service at National Institute of Oceanography (India)

    Kadam, A; Rokade, M.A

    A tar residue from Mumbai Beach, Maharashtra, India was matched with the suspected source sample from a tanker using UV, IR and GLC techniques. Negligible differences in several ratios of UV absorbances and ratios of infrared transmittances...

  14. Fugitive emissions control on dry copper tailing with crushed rock armor

    International Nuclear Information System (INIS)

    Haase, E.F.

    1992-01-01

    Four inactive copper tailing impoundments totalling 1,900 acres near Ajo in southwestern Arizona were covered on horizontal surfaces with a 2 in. nominal thickness of crushed rock to control particulate emissions. The tailings are typically dominated by sand-sized particles but may also include significant PM 10 fractions towards the centers of the impoundments. The technology was selected by Phelps Dodge Corporation, after investigation of several alternatives, as a permanent and practical cover that essentially eliminates fugitive emissions. It simulates the natural desert pavement that characterizes this arid area of the Sonoran Desert. Rocky overburden was crushed to minus 3 in. diameter and broadcast on dry surfaces of tailing impoundments with all-terrain, balloon-tired spreaders. Stony residues in the rock armor tend to cement together following rainfall, forming a crust that enhances surface stability and erosion control. Slopes with windblown tailing deposition were covered to a nominal 6 in. thickness by conventional dozer pushing and blading of minus 10 in. rock over the sides. Athel trees, planted extensively since 1970 on two of the four inactive impoundments, provided partial control of fugitives, but were subjected to harsh environmental conditions, including abrasion from saltating particles. The rock armor functions as a mulch which is expected to improve water relations for existing vegetation and areas seeded with native species. New surface microenvironments, and the virtual elimination of surface creep and saltation, are expected to support native plant growth under favorable climatic conditions

  15. Anomalous capillary flow of coal tar pitches

    Energy Technology Data Exchange (ETDEWEB)

    Saint Romain, J.L.; Lahaye, J.; Ehrburger, P.; Couderc, P.

    1986-06-01

    Capillary flow of liquid coal tar pitch into a coke bed was studied. Anomalies in the flow could not be attributed to a plugging effect for mesophase content lower than 20 wt%. The flow behaviour of small pitch droplets can be correlated with the change in physicochemical properties, as measured by the glass transition temperature, on penetration into the coke bed. 4 references.

  16. Uranium mill tailings backfill management. Final report

    International Nuclear Information System (INIS)

    Thomson, B.M.; Heggen, R.J.

    1984-01-01

    Backfilling, the disposal of spent uranium mill tailings in empty mine stopes, has been practiced in the Grants Mineral Belt of New Mexico for nearly 20 years. The principal objective of backfilling is the prevention of roof collapse and hydraulic connection with overlying aquifers, increasing mine dewatering requirements. Backfilling is accomplished by gravity feed of a slurry of sand-fraction tailings and treated mine water into the slope. The effects of backfilling on surface discharge of mine wastewater are negligible due to the small fraction of the total flow represented by slurry decant. Furthermore, quality of the decant is not significantly below that of other mine waters. Groundwater effects of backfilling may be classified as short-term (while the mine is operational) and long-term (after dewatering operations have been terminated). Short-term effects are insignificant because of rapid and continuous flow to the mine sump. Long-term effects on aquifer water quality are predicted to be minimal due to (1) the small amount of slurry liquor present after drainage, (2) the precipitation of SO 4 and CO 3 phases, and (3) the reestablishment of reducing conditions and subsequent precipitation of major contaminants including U, As, Mo, Se, and V. 28 references, 19 figures, 9 tables

  17. Sand transportation and reverse patterns over leeward face of sand dune

    Science.gov (United States)

    Jiang, Hong; Dun, Hongchao; Tong, Ding; Huang, Ning

    2017-04-01

    Sand saltation has complex interactions with turbulent flow and dune form. Most models of wind-blown sand consider ideal circumstances such as steady wind velocity and a flat surface, and the bulk of data on wind flow and sand transport over an individual dune has focused mostly on the influence of dune shape or inter-dune space on the wind flow, neglecting the effect of morphology on sand saltation, particularly airflow and sand transportation over the leeward slope. Wind flow structures over the leeward slope of sand dunes have a fundamental influence on the organization of sand dunes. In order to understand sand dune dynamics, lee face airflow and sediment transportation should be paid more attention. Previous field observations could not measure turbulent flow structure well because of the limited observation points and the influence of experiment structure on wind field. In addition, the reverse sand particles over leeward face could not be collected by sand trap in field. Numerous field observations could not measure turbulent flow structure because of the limited observation points and the influence of experimental structures on the wind field. In addition, the reverse transport of sand particles over leeward face could not be collected by sand traps in field. Therefore, this paper aims to investigate the turbulent flow structure and sand transport pattern over the leeward slope. A numerical model of sand saltation over slope terrain is constructed, which also considers the coupling effects between air flow and sand particles. The large eddy simulation method is used to model turbulent flow. Sand transport is simulated by tracking the trajectory of each sand particle. The results show that terrain significantly alters the turbulent air flow structure and wind-blown sand movement, especially over the leeward slope. Here, mass flux increases initially and then decreases with height in the reversed flow region in the direction of wind flow, and the mass flux

  18. HuMiTar: A sequence-based method for prediction of human microRNA targets

    Directory of Open Access Journals (Sweden)

    Chen Ke

    2008-12-01

    Full Text Available Abstract Background MicroRNAs (miRs are small noncoding RNAs that bind to complementary/partially complementary sites in the 3' untranslated regions of target genes to regulate protein production of the target transcript and to induce mRNA degradation or mRNA cleavage. The ability to perform accurate, high-throughput identification of physiologically active miR targets would enable functional characterization of individual miRs. Current target prediction methods include traditional approaches that are based on specific base-pairing rules in the miR's seed region and implementation of cross-species conservation of the target site, and machine learning (ML methods that explore patterns that contrast true and false miR-mRNA duplexes. However, in the case of the traditional methods research shows that some seed region matches that are conserved are false positives and that some of the experimentally validated target sites are not conserved. Results We present HuMiTar, a computational method for identifying common targets of miRs, which is based on a scoring function that considers base-pairing for both seed and non-seed positions for human miR-mRNA duplexes. Our design shows that certain non-seed miR nucleotides, such as 14, 18, 13, 11, and 17, are characterized by a strong bias towards formation of Watson-Crick pairing. We contrasted HuMiTar with several representative competing methods on two sets of human miR targets and a set of ten glioblastoma oncogenes. Comparison with the two best performing traditional methods, PicTar and TargetScanS, and a representative ML method that considers the non-seed positions, NBmiRTar, shows that HuMiTar predictions include majority of the predictions of the other three methods. At the same time, the proposed method is also capable of finding more true positive targets as a trade-off for an increased number of predictions. Genome-wide predictions show that the proposed method is characterized by 1.99 signal

  19. Oil sands mine pit wall design and performance at Syncrude

    Energy Technology Data Exchange (ETDEWEB)

    Cameron, R.; Danku, M; Purhar, G. [Syncrude Canada Ltd., Fort McMurray, AB (Canada)

    2008-07-01

    This study conducted slope stability analyses in order to compare pit performance at an oil sands mine with results from computerized simulations using conventionally known soil parameters. Ranges included fully-drained to fully-saturated piezometric conditions; full-peak strength conditions; fully-softened peak conditions; residual shear strength conditions; and undrained shear strength considerations. Pit wall designs were reviewed and a history of marine clay layers at the mine was presented. Assumed overburden fall-down limits were considered. Shovel overburden slope angles were calculated. An analysis of the review suggested that steeper pit walls provide less room for error and have a higher rate of failures. Incised pleistocene channels, joint and fracture areas as well as higher piezometric level areas also impacted on slope performance. Failed areas influenced ore volumes and led to productivity reductions below 50 per cent. It was concluded that the overburden portions of the oil sands mine ranged between 4H:1V to 5H:1V due to haul roads and the timing of top-bench pushbacks. Future plans for the mine must consider ore inventories, haul road requirements; running surface requirements; and ramping accesses. Future slopes at the oil sands mine will be buttressed with overburden and tailings storage areas, while longer-term slopes will be flattened. 6 refs., 2 tabs., 11 figs.

  20. Choosing between a rock and a hard place: Camouflage in the round-tailed horned lizard Phrynosoma modestum

    Directory of Open Access Journals (Sweden)

    William E. COOPER, Jr., Wade C. SHERBROOKE

    2012-08-01

    Full Text Available The round-tailed horned lizard Phrynosoma modestum is cryptically colored and resembles a small stone when it draws legs close to its body and elevates its back. We investigated effectiveness of camouflage in P. modestum and its dependence on stones by placing a lizard in one of two microhabitats (uniform sand or sand with surface rocks approximately the same size as lizards. An observer who knew which microhabitat contained the lizard was asked to locate the lizard visually. Latency to detection was longer and probability of no detection within 60 s was higher for lizards on rock background than on bare sand. In arenas where lizards could choose to occupy rock or bare sand, much higher proportions selected rocky backgrounds throughout the day; at night all lizards slept among stones. A unique posture gives P. modestum a rounded appearance similar to many natural stones. Lizards occasionally adopted the posture, but none did so in response to a nearby experimenter. Stimuli that elicit the posture are unknown. That P. modestum is better camouflaged among rocks than on bare sand and prefers to occupy rocky areas suggests that special resemblance to rocks (masquerade enhances camouflage attributable to coloration and immobility [Current Zoology 58 (4: 541–548, 2012].

  1. Recovery of naphthalene, anthracene, etc. , from tar

    Energy Technology Data Exchange (ETDEWEB)

    1920-12-25

    A process is described for the recovery of naphthalene, anthracene, and the like from tar oils and similar liquors, characterized in that the oil is treated in a rapidly rotating hammer mill, such as a colloid mill, with water sufficient, in the presence or absence of suitable solvents, for the only portion preferably in the presence of emulsifiers; and is filtered through a filter with fine pores.

  2. Lab-scale pyrolysis of the Automotive Shredder Residue light fraction and characterization of tar and solid products.

    Science.gov (United States)

    Anzano, Manuela; Collina, Elena; Piccinelli, Elsa; Lasagni, Marina

    2017-06-01

    The general aim of this study is the recovery of Automotive Shredder Residue (ASR). The ASR light fraction, or car fluff, that was collected at an Italian shredding plant was pyrolysed at various temperatures (500-800°C) in a lab-scale reactor. The condensable gases (tar) and solid residue yields increased with decreasing temperature, and these products were characterized to suggest a potential use to reclaim them. The higher heating value (HHV) of tar was 34-37MJ/kg, which is comparable with those of fossil fuels. Furthermore, the ash content was low (0.06-4.98%). Thus, tar can be used as an alternative fuel. With this prospect, the concentrations of polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in tar were determined. The toxicity of tar changes with temperature (1-5ng I-TEQ/g), and the PCDFs significantly contribute to tar toxicity, which was 75-100% with a maximum of 99.6% at 700°C. Regarding the characterization of the solid residue, the low HHV (2.4-3.3MJ/kg) does not make it suitable for energy recovery. Regarding material recovery, we considered its use as a filler in construction materials or a secondary source for metals. It shows a high metal concentration (280,000-395,000mg/kg), which is similar at different pyrolysis temperatures. At 500°C, polycyclic aromatic hydrocarbons (PAHs) were not detected in the solid residue, whereas the maximum total PAH concentration (19.41ng/g, 700°C) was lower than that in fly ash from MSWI. In conclusion, 500°C is a suitable pyrolysis temperature to obtain valuable tar and solid residue. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Concentrations of polycyclic aromatic hydrocarbons (PAHs) and azaarenes in runoff from coal-tar- and asphalt-sealcoated pavement

    International Nuclear Information System (INIS)

    Mahler, Barbara J.; Van Metre, Peter C.; Foreman, William T.

    2014-01-01

    Coal-tar-based sealcoat, used extensively on parking lots and driveways in North America, is a potent source of PAHs. We investigated how concentrations and assemblages of PAHs and azaarenes in runoff from pavement newly sealed with coal-tar-based (CT) or asphalt-based (AS) sealcoat changed over time. Samples of simulated runoff were collected from pavement 5 h to 111 d following application of AS or CT sealcoat. Concentrations of the sum of 16 PAHs (median concentrations of 328 and 35 μg/L for CT and AS runoff, respectively) in runoff varied relatively little, but rapid decreases in concentrations of azaarenes and low molecular weight PAHs were offset by increases in high molecular weight PAHs. The results demonstrate that runoff from CT-sealcoated pavement, in particular, continues to contain elevated concentrations of PAHs long after a 24-h curing time, with implications for the fate, transport, and ecotoxicological effects of contaminants in runoff from CT-sealcoated pavement. - Highlights: • We compare PAH and azaarene concentrations in runoff from coal-tar- and asphalt-sealed pavement. • Concentrations in coal-tar-sealcoat runoff greatly exceeded those in asphalt-sealcoat runoff. • Decreases in azaarenes and LMW PAHs were offset by increases in HMW PAHs. • PAH concentrations in coal-tar-sealcoat runoff remained high for months after application. - Concentrations of PAHs in runoff from pavement with coal-tar-based sealcoat continue to be elevated for at least 3 months following sealcoat application

  4. Telling tails: selective pressures acting on investment in lizard tails.

    Science.gov (United States)

    Fleming, Patricia A; Valentine, Leonie E; Bateman, Philip W

    2013-01-01

    Caudal autotomy is a common defense mechanism in lizards, where the animal may lose part or all of its tail to escape entrapment. Lizards show an immense variety in the degree of investment in a tail (i.e., length) across species, with tails of some species up to three or four times body length (snout-vent length [SVL]). Additionally, body size and form also vary dramatically, including variation in leg development and robustness and length of the body and tail. Autotomy is therefore likely to have fundamentally different effects on the overall body form and function in different species, which may be reflected directly in the incidence of lost/regenerating tails within populations or, over a longer period, in terms of relative tail length for different species. We recorded data (literature, museum specimens, field data) for relative tail length (n=350 species) and the incidence of lost/regenerating tails (n=246 species). We compared these (taking phylogeny into account) with intrinsic factors that have been proposed to influence selective pressures acting on caudal autotomy, including body form (robustness, body length, leg development, and tail specialization) and ecology (foraging behavior, physical and temporal niches), in an attempt to identify patterns that might reflect adaptive responses to these different factors. More gracile species have relatively longer tails (all 350 spp., P lost/regenerating tails for nocturnal lizards (all 246 spp., P pressure.

  5. PAH volatilization following application of coal-tar-based pavement sealant

    Science.gov (United States)

    Van Metre, Peter C.; Majewski, Michael S.; Mahler, Barbara J.; Foreman, William T.; Braun, Christopher L.; Wilson, Jennifer T.; Burbank, Teresa L.

    2012-01-01

    Coal-tar-based pavement sealants, a major source of PAHs to urban water bodies, have recently been identified as a source of volatile PAHs to the atmosphere. We tracked the volatilization of PAHs for 1 year after application of a coal-tar-based pavement sealant by measuring gas-phase PAH concentrations above the pavement surface and solid-phase PAH concentrations in sealant scraped from the surface. Gas-phase concentrations at two heights (0.03 and 1.28 m) and wind speed were used to estimate volatilization flux. The sum of the concentrations of eight frequently detected PAHs (ΣPAH8) in the 0.03-m sample 1.6 h after application (297,000 ng m-3) was about 5000 times greater than that previously reported for the same height above unsealed parking lots (66 ng m-3). Flux at 1.6 h after application was estimated at 45,000 μg m-2 h-1 and decreased rapidly during the 45 days after application to 160 μg m-2 h-1. Loss of PAHs from the adhered sealant also was rapid, with about a 50% decrease in solid-phase ΣPAH8 concentration over the 45 days after application. There was general agreement, given the uncertainties, in the estimated mass of ΣPAH8 lost to the atmosphere on the basis of air sampling (2–3 g m-2) and adhered sealant sampling (6 g m-2) during the first 16 days after application, translating to a loss to the atmosphere of one-quarter to one-half of the PAHs in the sealcoat product. Combining the estimated mass of ΣPAH8 released to the atmosphere with a national-use estimate of coal-tar-based sealant suggests that PAH emissions from new coal-tar-based sealcoat applications each year (~1000 Mg) are larger than annual vehicle emissions of PAHs for the United States.

  6. Newest oil sands mine on the horizon : Fort McMurray's next megaproject

    Energy Technology Data Exchange (ETDEWEB)

    Werniuk, J.

    2005-08-01

    The newly approved Horizon mine project and on-site upgrader project will be one of Canada's largest oil sands operation. The site for the facility is 70 km north of Fort McMurray, Alberta. Drilling has revealed an in-place resource of 16 billion bbl of bitumen, of which 6 billion bbl is potentially recoverable using existing mining technologies. In situ recovery potential on the western parts of the lease will be used to obtain additional resources. Horizon is owned by Calgary-based Canadian Natural Resource Limited, the second largest oil and gas company in Canada. This senior oil and gas company has operations in western Canada, the United Kingdom, the North Sea and offshore West Africa. The 3-phase Horizon project will have a capital of $10.8 billion, including contingencies. The mine will be a truck and shovel operation, mining 450,000 tonnes of oil sand daily from 2 main pits. The clean, diluted bitumen from the froth treatment plant will be sent to an onsite upgrader that will use delayed coking technology to recover 99 per cent of the sulphur using a tail gas cleanup unit. All of the product will be hydrotreated. In the first phase, the mine will produce sweet synthetic crude oil by the second half of 2008 at a daily rate of 110,000 bbl. This will increase in the second phase to 155,000 bbl per day SCO by 2010 and to 232,000 bbl per day SCO by 2012. The tailings during the first phase will be sent to a conventional tailings pond. A non-segregating tailings disposal method will be considered for the second phase to reduce the size of the required tailings pond and to leave less of an environmental footprint. A 1.83 million cubic metre raw water pond is being built into the project to recycle as much of the water as possible. The Horizon leases include traditional lands of several First Nation bands. Canadian Natural is involving Aboriginal communities in the project through employment and consultation for traditional environmental knowledge. During peak

  7. Site-selective probing of cTAR destabilization highlights the necessary plasticity of the HIV-1 nucleocapsid protein to chaperone the first strand transfer

    Science.gov (United States)

    Godet, Julien; Kenfack, Cyril; Przybilla, Frédéric; Richert, Ludovic; Duportail, Guy; Mély, Yves

    2013-01-01

    The HIV-1 nucleocapsid protein (NCp7) is a nucleic acid chaperone required during reverse transcription. During the first strand transfer, NCp7 is thought to destabilize cTAR, the (−)DNA copy of the TAR RNA hairpin, and subsequently direct the TAR/cTAR annealing through the zipping of their destabilized stem ends. To further characterize the destabilizing activity of NCp7, we locally probe the structure and dynamics of cTAR by steady-state and time resolved fluorescence spectroscopy. NC(11–55), a truncated NCp7 version corresponding to its zinc-finger domain, was found to bind all over the sequence and to preferentially destabilize the penultimate double-stranded segment in the lower part of the cTAR stem. This destabilization is achieved through zinc-finger–dependent binding of NC to the G10 and G50 residues. Sequence comparison further revealed that C•A mismatches close to the two G residues were critical for fine tuning the stability of the lower part of the cTAR stem and conferring to G10 and G50 the appropriate mobility and accessibility for specific recognition by NC. Our data also highlight the necessary plasticity of NCp7 to adapt to the sequence and structure variability of cTAR to chaperone its annealing with TAR through a specific pathway. PMID:23511968

  8. Marketing 'less harmful, low-tar' cigarettes is a key strategy of the industry to counter tobacco control in China.

    Science.gov (United States)

    Yang, Gonghuan

    2014-03-01

    While the 'low-tar' scheme has been widely recognised as a misleading tactic used by the tobacco industry to deceive the public about the true risks of cigarette smoking, a similar campaign using the slogan of 'less harmful, low tar' was launched by the Chinese tobacco industry, that is, State Tobacco Monopoly Administration/China National Tobacco Corporation and began to gain traction during the last decade. Despite the fact that no sufficient research evidence supports the claims made by the industry that these cigarettes are safer, the Chinese tobacco industry has continued to promote them using various health claims. As a result, the production and sales of 'less harmful, low-tar' cigarettes have increased dramatically since 2000. Recently, a tobacco industry senior researcher, whose main research area is 'less harmful, low-tar' cigarettes, was elected as an Academician to the prestigious Chinese Academy of Engineering for his contribution to developing 'less harmful, low-tar' cigarettes. The tobacco researcher's election caused an outcry from the tobacco control community and the general public in China. This paper discusses the Chinese tobacco industry's 'less harmful, low-tar' initiatives and calls for the Chinese government to stop the execution of this deceptive strategy for tobacco marketing.

  9. Reclaimability of the spent sand mixture – sand with bentonite – sand with furfuryl resin

    Directory of Open Access Journals (Sweden)

    J. Dańko

    2011-04-01

    Full Text Available Introduction of new binding materials and new technologies of their hardening in casting moulds and cores production requires theapplication of reclamation methods adequate to their properties as well as special devices realizing tasks. The spent sands circulationsystem containing the same kind of moulding and core sands is optimal from the point of view of the expected reclamation results.However, in the face of a significant variability of applied technologies and related to them various reclamation methods, the need - of theobtained reclamation products assessment on the grounds of systematic criteria and uniform bases – arises, with a tendency of indicatingwhich criteria are the most important for the given sand system. The reclaimability results of the mixture of the spent moulding sand withGeko S bentonite and the spent core sand with the Kaltharz 404U resin hardened by acidic hardener 100 T3, are presented in the paper.Investigations were performed with regard to the estimation of an influence of core sands additions (10 –25% on the reclaimed materialquality. Dusts and clay content in the reclaim, its chemical reaction (pH and ignition loss were estimated. The verification of the reclaiminstrumental assessment was performed on the basis of the technological properties estimation of moulding sand with bentonite, where the reclaimed material was used as a matrix.

  10. Quantitative determination of acid oils in low-temperature coal tar by means of fractional distillation

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, A

    1950-01-01

    The aromatic hydroxy compounds in low-temperature tar were separated, and 75 compounds in the boiling range 180/sup 0/ to 320/sup 0/ isolated by means of fractional distillation in packed columns of at least 45 theoretical plates. Mixtures not separable by fractionation were separated by means of other physicochemical or chemical methods. Hydroxy compounds with boiling point up to 230/sup 0/C were detemined quantitatively, as were the phenols present in low-temperature carbonization liquors. With the Krupp-Lurgi process of low-temperature carbonization, 1.8% phenol, 1.8% o-cresol, and 3.6% m-p-cresols were formed. The tar contained up to 1.3% 1:3:5-xylenol and up to 0.9% 1:2:4-xylenol. Of the 12.1% v/v of phenol, cresols, and xylenols present in tar, 11.2% were determined quantitatively, and 9 hydroxy compounds were identified in the remaining 0.9%. On the basis of these investigations, a technical plant that permitted the recovery of pure low-temperature tar phenols and the preparation of a number of different phenol resins from the mixtures was erected.

  11. Studies estimating the dermal bioavailability of polynuclear aromatic hydrocarbons from manufactured plant tar-contaminated soils

    International Nuclear Information System (INIS)

    Roy, T.A.; Krueger, A.J.; Taylor, B.B.; Mauro, D.M.; Goldstein, L.S.

    1998-01-01

    In vitro percutaneous absorption studies were performed with contaminated soils or organic extracts of contaminated soils collected at manufactured gas plant (MGP) sites. The MGP tar contaminated soils were found to contain a group of targeted polynuclear aromatic hydrocarbons (PAH) at levels ranging from 10 to 2400 mg/kg. The soil extracts contained target PAH at levels ranging from 12 000 - 34 000 mg/kg. Dermal penetration rates of target PAH from the MGP tar-contaminated soils/soil extracts were determined experimentally through human skin using 3 H-benzo(a)pyrene (BaP) as a surrogate. Results from three MGP sites showed reductions of 2-3 orders of magnitude in PAH absorption through human skin from the most contaminated soils in comparison to the soil extracts. Reduction in PAH penetration can be attributed to PAH concentration and (soil) matrix properties. PAH dermal flux values are used to determine site-specific dermally absorbed dose (DAD) and chronic daily intake (CDI) which are essential terms required to estimate risk associated with human exposure to MGP tar and MGP tar-contaminated soils. 21 refs., 4 figs., 3 tabs

  12. Tar removal from biomass gasification streams: processes and catalysts; Remocao do alcatrao de correntes de gaseificacao de biomassa: processos e catalisadores

    Energy Technology Data Exchange (ETDEWEB)

    Quitete, Cristina P.B. [Centro de Pesquisa e Desenvolvimento Leopoldo Americo Miguez de Mello (CENPES/PETROBRAS), Rio de Janeiro, RJ (Brazil). Processos de Conversao de Biomassa; Souza, Mariana M.V.M., E-mail: mmattos@eq.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Centro de Tecnologia. Escola de Quimica

    2014-07-01

    Biomass gasification is a technology that has attracted great interest in synthesis of biofuels and oxo alcohols. However, this gas contains several contaminants, including tar, which need to be removed. Removal of tar is particularly critical because it can lead to operational problems. This review discusses the major pathways to remove tar, with a particular focus on the catalytic steam reforming of tar. Few catalysts have shown promising results; however, long-term studies in the context of real biomass gasification streams are required to realize their potential. (author)

  13. Tail posture predicts tail biting outbreaks at pen level in weaner pigs

    DEFF Research Database (Denmark)

    Lahrmann, Helle Pelant; Hansen, Christian Fink; D'Eath, Rick

    2018-01-01

    posture and behaviour could be detected at pen level between upcoming tail biting pens (T-pens) and control pens (C-pens). The study included 2301 undocked weaner pigs in 74 pens (mean 31.1 pigs/pen; SD 1.5). Tails were scored three times weekly (wound freshness, wound severity and tail length) between 07......Detecting a tail biting outbreak early is essential to reduce the risk of pigs getting severe tail damage. A few previous studies suggest that tail posture and behavioural differences can predict an upcoming outbreak. The aim of the present study was therefore to investigate if differences in tail......:00 h-14:00 h from weaning until a tail biting outbreak. An outbreak (day 0) occurred when at least four pigs had a tail damage, regardless of wound freshness. On average 7.6 (SD 4.3) pigs had a damaged tail (scratches + wound) in T-pens on day 0. Tail posture and behaviour (activity, eating...

  14. Human papillomavirus and tar hypothesis for squamous cell cervical ...

    Indian Academy of Sciences (India)

    2010-08-09

    Aug 9, 2010 ... Keywords. Cervical cancer; co-factors; human papillomavirus; tar-based vaginal douche; tobacco smoke; wood smoke. Author Affiliations. Christina Bennett1 Allen E Kuhn2 Harry W Haverkos3. Indiana University School of Medicine, Indianapolis, Indiana 46202-5149, USA; Suite 300, Hamilton Mason Road ...

  15. Coal-tar-based sealcoated pavement: A major PAH source to urban stream sediments

    International Nuclear Information System (INIS)

    Witter, Amy E.; Nguyen, Minh H.; Baidar, Sunil; Sak, Peter B.

    2014-01-01

    We used land-use analysis, PAH concentrations and assemblages, and multivariate statistics to identify sediment PAH sources in a small (∼1303 km 2 ) urbanizing watershed located in South-Central, Pennsylvania, USA. A geographic information system (GIS) was employed to quantify land-use features that may serve as PAH sources. Urban PAH concentrations were three times higher than rural levels, and were significantly and highly correlated with combined residential/commercial/industrial land use. Principal components analysis (PCA) was used to group sediments with similar PAH assemblages, and correlation analysis compared PAH sediment assemblages to common PAH sources. The strongest correlations were observed between rural sediments (n = 7) and coke-oven emissions sources (r = 0.69–0.78, n = 5), and between urban sediments (n = 22) and coal-tar-based sealcoat dust (r = 0.94, n = 47) suggesting that coal-tar-based sealcoat is an important urban PAH source in this watershed linked to residential and commercial/industrial land use. -- Highlights: • Total PAH concentrations were measured at 35 sites along an urbanizing land-use gradient. • PAH concentrations increased with increasing urban land-use. • Urban land-use metrics were measured at three spatial scales using GIS. • PAH assemblages indicate coal-tar-based sealcoat is a major urban PAH source. • PAH assemblages indicate coke-oven emissions are an important rural PAH source. -- Coal-tar-based sealcoated pavement is a major PAH source to urban freshwater stream sediments in south-central Pennsylvania, USA

  16. Social-cognitive remediation in schizophrenia: generalization of effects of the Training of Affect Recognition (TAR).

    Science.gov (United States)

    Wölwer, Wolfgang; Frommann, Nicole

    2011-09-01

    In the last decade, several social cognitive remediation programs have been developed for use in schizophrenia. Though existing evidence indicates that such programs can improve social cognition, which is essential for successful social functioning, it remains unclear whether the improvements generalize to social cognitive domains not primarily addressed by the intervention and whether the improved test performance transfers into everyday social functioning. The present study investigated whether, beyond its known effects on facial affect recognition, the Training of Affect Recognition (TAR) has effects on prosodic affect recognition, theory of mind (ToM) performance, social competence in a role-play task, and more general social and occupational functioning. Thirty-eight inpatients with a diagnosis of schizophrenia or schizoaffective disorder were randomly assigned to 6 weeks of treatment with the TAR--primarily targeted at facial affect recognition-or Cognitive Remediation Training (CRT)--primarily targeted at neurocognition. Intention-to-treat analyses found significantly larger pre-post improvements with TAR than with CRT in prosodic affect recognition, ToM, and social competence and a trend effect in global social functioning. However, the effects on ToM and social competence were no longer significant in the smaller group of patients who completed treatment according to protocol. Results suggest that TAR effects generalize to other social cognitive domains not primarily addressed. TAR may also enhance social skills and social functioning, although this has to be confirmed. Results are discussed with regard to the need to improve functional outcome in schizophrenia against the background of current evidence from other social cognitive remediation approaches.

  17. Gc/ms analysis of coal tar composition produced from coal

    African Journals Online (AJOL)

    Coal pyrolysis is one of the significant approaches for the comprehensive utilization ... planigraphy-GC/MS; therefore a satisfactory analytical result obtained, which .... Among the aliphatic group of the coal tar, the proportion of alkene is larger ...

  18. Evaluating the Metal Tolerance Capacity of Microbial Communities Isolated from Alberta Oil Sands Process Water.

    Directory of Open Access Journals (Sweden)

    Mathew L Frankel

    Full Text Available Anthropogenic activities have resulted in the intensified use of water resources. For example, open pit bitumen extraction by Canada's oil sands operations uses an estimated volume of three barrels of water for every barrel of oil produced. The waste tailings-oil sands process water (OSPW-are stored in holding ponds, and present an environmental concern as they are comprised of residual hydrocarbons and metals. Following the hypothesis that endogenous OSPW microbial communities have an enhanced tolerance to heavy metals, we tested the capacity of planktonic and biofilm populations from OSPW to withstand metal ion challenges, using Cupriavidus metallidurans, a known metal-resistant organism, for comparison. The toxicity of the metals toward biofilm and planktonic bacterial populations was determined by measuring the minimum biofilm inhibitory concentrations (MBICs and planktonic minimum inhibitory concentrations (MICs using the MBEC ™ assay. We observed that the OSPW community and C. metallidurans had similar tolerances to 22 different metals. While thiophillic elements (Te, Ag, Cd, Ni were found to be most toxic, the OSPW consortia demonstrated higher tolerance to metals reported in tailings ponds (Al, Fe, Mo, Pb. Metal toxicity correlated with a number of physicochemical characteristics of the metals. Parameters reflecting metal-ligand affinities showed fewer and weaker correlations for the community compared to C. metallidurans, suggesting that the OSPW consortia may have developed tolerance mechanisms toward metals present in their environment.

  19. Consolidation and atmospheric drying of fine oil sand tailings : Comparison of blind simulations and field scale results

    NARCIS (Netherlands)

    Vardon, P.J.; Yao, Y.; van Paassen, L.A.; van Tol, A.F.; Sego, D.C.; Wilson, G.W.; Beier, N.A.

    2016-01-01

    This paper presents a comparison between blind predictions of field tests of atmospheric drying of mature fine tailings (MFT) presented in IOSTC 2014 and field results. The numerical simulation of the consolidation and atmospheric drying of selfweight consolidating fine material is challenging and

  20. Cigarettes, lung cancer, and coronary heart disease: the effects of inhalation and tar yield.

    Science.gov (United States)

    Higenbottam, T; Shipley, M J; Rose, G

    1982-06-01

    Ten-year mortality rates for lung cancer and coronary heart disease have been related to cigarette smoking habits in 17 475 male civil servants aged 40-64 and in sample of 8089 male British residents aged 35-69. Both diseases were more frequent in smokers. Lung cancer rates were higher overall for "non-inhalers", particularly in heavy smokers. Tar yield correlated with the risk of lung cancer in non-inhalers but less so in inhalers. Conversely, coronary deaths were more common among inhalers, and the effect of tar/nicotine yield (such as it was) was confined to inhalers. It appears that there are subtle interactions between the amount smoked, the tar/nicotine yield of the cigarette, and the style of smoking. Thus the effects of a change in cigarette characteristics are hard to predict, and they may be different for respiratory and cardiovascular disease.

  1. Properties of gasification-derived char and its utilization for catalytic tar reforming

    Science.gov (United States)

    Qian, Kezhen

    Char is a low-value byproduct of biomass gasification and pyrolysis with many potential applications, such as soil amendment and the synthesis of activated carbon. The overall goal of the proposed research was to develop novel methods to use char derived from gasification for high-value applications in syngas conditioning. The first objective was to investigate effects of gasification condition and feedstock on properties of char derived from fluidized bed gasification. Results show that the surface areas of most of the char were 1--10 m 2/g and increased as the equivalence ratio increased. Char moisture and fixed carbon contents decreased while ash content increased as equivalence ratio increased. The next objective was to study the properties of sorghum and red cedar char derived from downdraft gasifier. Red cedar char contained more aliphatic carbon and o-alkyl carbon than sorghum char. Char derived from downdraft gasification had higher heating values and lower ash contents than char derived from fluidized bed gasification. The gasification reactivity of red cedar char was higher than that of sorghum char. Then, red cedar char based catalysts were developed with different preparation method to reform toluene and naphthalene as model tars. The catalyst prepared with nickel nitrate was found to be better than that with nickel acetate. The nickel particle size of catalyst impregnated with nickel nitrate was smaller than that of catalyst impregnated with nickel acetate. The particle size of catalyst impregnated with nickel acetate decreased by hydrazine reduction. The catalyst impregnated with nickel nitrate had the highest toluene removal efficiency, which was 70%--100% at 600--800 °C. The presence of naphthalene in tar reduced the catalyst efficiency. The toluene conversion was 36--99% and the naphthalene conversion was 37%--93% at 700--900 °C. Finally, effects of atmosphere and pressure on catalytic reforming of lignin-derived tars over the developed catalyst

  2. Characterization of alkanes, hopanes, and polycyclic aromatic hydrocarbons (PAHs) in tar-balls collected from the East Coast of Peninsular Malaysia.

    Science.gov (United States)

    Chandru, Kuhan; Zakaria, Mohamad Pauzi; Anita, Sofia; Shahbazi, Azadeh; Sakari, Mahyar; Bahry, Pourya Shahpoury; Mohamed, Che Abd Rahim

    2008-05-01

    The East Coast of Peninsular Malaysia faces the South China Sea and is vulnerable to oil pollution because of intense petroleum production activities in the area. The South China Sea is also a favored route for supertankers carrying crude oil to the Far East. Consequently, oil spills can occur, causing pollution and contamination in the surrounding areas. Residual oil spills stranded on coastal beaches usually end up as tar-balls. Elucidating the sources of tar-balls using a molecular marker approach is essential in assessing environmental impacts and perhaps settling legal liabilities for affected parties. This study utilizes a multimodal molecular marker approach through the use of diagnostic ratios of alkanes, hopanes, and polycyclic aromatic hydrocarbons (PAHs) to determine the source, distribution and weathering of tar-balls. Hopane ratios (e.g., C29/C30, and summation C31-C35/C30 ratios) were used to identify the sources of tar-balls. The weathering effects were distinguished by using alkanes, namely the unresolved complex mixture (UCM) and low molecular weight/high molecular weight (L/H) ratios. Similarly, PAHs were also used for the determination of weathering processes undergone by the tar-balls. This multimodal molecular marker gave a very strong indication of the sources of tar-balls in this study. For example, 16 out of 17 samples originated from South East Asian Crude Oil (SEACO) with one sample from Merang, Terengganu originating from North Sea Oil (Troll). The TRME-2 sample may have come from a supertanker's ballast water discharge. The second possibility is that the tar-ball may have been transported via oceanographic currents. All 'weathered' sample characterizations were based on the presence of UCM and other ratios. The multimodal molecular marker approach applied in this study has enabled us to partially understand the transport behavior of tar-balls in the marine environment and has revealed insights into the weathering process of tar-balls.

  3. Characterisation and catalytic upgrading of tars from coal-tyre hydropyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Mastral, A.M.; Murillo, R.; Callen, M.S.; Garcia, T. [Instituto de Carboquimica, Zaragoza (Spain)

    1999-07-01

    Tars from coal-tyre hydropyrolysis obtained in a swept fixed bed reactor were upgraded with catalysts. Upgraded oils were characterized, and naphtha, kerosene, gas oil, heavy gas oil and vacuum residue percentages were quantified. 7 refs., 3 tabs.

  4. Guideline for Sampling and Analysis of Tar and Particles in Biomass Producer Gases. Version 3.3

    Energy Technology Data Exchange (ETDEWEB)

    Neeft, J.P.A.; Knoef, H.A.M.; Zielke, U.; Sjoestroem, K.; Hasler, P.; Simell, P.A.; Dorrington, M.A.; Thomas, L.; Abatzoglou, N.; Deutch, S.; Greil, C.; Buffinga, G.J.; Brage, C.; Suomalainen, M.

    2002-07-01

    This Guideline provides a set of procedures for the measurement of organic contaminants and particles in producer gases from biomass gasifiers. The procedures are designed to cover different gasifier types (updraft or downdraft fixed bed or fluidised bed gasifiers), operating conditions (0 - 900C and 0.6-60 bars) and concentration ranges (1 mg/m{sub n}{sup 3} to 300 g/m{sub n}{sup 3}). The Guideline describes a modular sampling train, and a set of procedures, which include: planning and preparation of the sampling, sampling and post-sampling, analysis, calculations, error analysis and reporting. The modular sampling train consists of 4 modules. Module 1 is a preconditioning module for isokinetic sampling and gas cooling. Module 2 is a particle collection module including a heated filter. Module 3 is a tar collection module with a gas quench (optionally by circulating a liquid), impinger bottles and a backup adsorber. Module 4 is a volume-sampling module consisting of a pump, a rotameter, a gas flow meter and pressure and temperature indicators. The equipment and materials that are required for procuring this modular sampling train are given in the Guideline. The sampling procedures consist of a description for isokinetic sampling, a leakage test prior to sampling, the actual sampling and its duration, how the equipment is cleaned after the sampling, and how the samples are prepared and stored. Analysis of the samples is performed via three procedures. Prior to these procedures, the sample is prepared by Soxhlet extraction of the tars on the particle filter and by collection of all tars in one bulk solution. The first procedure describes the weighing of the particle filter to obtain the concentration of particles in the biomass producer gas. The bulk tar solution is used for two purposes: for determination of gravimetric tar and for analysis of individual compounds. The second procedure describes how to determine the gravimetric tar mass from the bulk solution. The

  5. Treatment of low-temperature tar-gas mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Schick, F

    1928-07-04

    Process for the treating and conversion of low-temperature tar-vapor and gas mixtures in the presence of metals or metal oxides as well as bodies of large surface, without previous condensation of the liquid material to be treated, characterized by the treatment taking place with a mixture of desulfurizing metals and metal oxides which, if necessary, are precipitated on carriers and large surface nonmetal cracking catalysts, such as active carbon and silica gel.

  6. Receiving demulsifying agent from the acid tar

    Energy Technology Data Exchange (ETDEWEB)

    Nikitina, A.A.; Belyaeva, A.S.; Kunakova, R.V. [FGBIHE ' Ufa State Academy of Economics and Services' , Ufa (Russian Federation); Movsumzade, E.M. [FGBIHE ' Ufa State Petroleum Technological Univ.' , Ufa (Russian Federation); Lapidus, A.L. [Russian Academy of Sciences, Moscow (Russian Federation). N.D. Zelinsky Institute of Organic Chemistry

    2012-07-01

    The processing of wastes of petrochemical production makes it possible to reduce the price of produced commodity of petroleum products substantially. Bitumen, fuel oils, tars and other mixture of heavy organic compounds are widely used in road construction, in paint and cable industries, manufacture of roofing materials, are used as boiler and furnace fuel, fuel for marine diesel engines, raw material for the production of modifying additives, fillers, surfaceactive substances, etc. (orig.)

  7. Brown carbon in tar balls from smoldering biomass combustion

    Science.gov (United States)

    R. K. Chakrabarty; H. Moosmuller; L.-W. A. Chen; K. Lewis; W. P. Arnott; C. Mazzoleni; M. K. Dubey; C. E. Wold; W. M. Hao; S. M. Kreidenweis

    2010-01-01

    We report the direct observation of laboratory production of spherical, carbonaceous particles - "tar balls" - from smoldering combustion of two commonly occurring dry mid-latitude fuels. Real-time measurements of spectrally varying absorption Angstrom coefficients (AAC) indicate that a class of light absorbing organic carbon (OC) with wavelength dependent...

  8. Eastern Scheldt Sand, Baskarp Sand No. 15

    DEFF Research Database (Denmark)

    Andersen, A. T; Madsen, E. B.; Schaarup-Jensen, A. L.

    The present data report contains data from 13 drained triaxial tests, performed on two different sand types in the Soil Mechanics Laboratory at Aalborg University in March, 1997. Two tests have been performed on Baskarp Sand No. 15, which has already ken extensively tested in the Soil Mechanics...... Laboratory. The remaining 11 triaxial tests have ben performed on Eastern Scheldt Sand, which is a material not yet investigated at the Soil Mechanics Laboratory. In the first pari of this data report, the characteristics of the two sand types in question will be presented. Next, a description...... will described. In this connection, the procedure for preparation of the soil specimens will be presented, and the actual performance of the tests will be briefly outlined. Finally, the procedure for processing of the measurements from the laboratory in order to obtain usable data will be described. The final...

  9. Radiocarbon dating of extinct fauna in the Americas recovered from tar pits

    International Nuclear Information System (INIS)

    Jull, A.J.T.; Iturralde-Vinent, M.; O'Malley, J.M.; MacPhee, R.D.E.; McDonald, H.G.; Martin, P.S.; Moody, J.; Rincon, A.

    2004-01-01

    We have obtained radiocarbon dates by accelerator mass spectrometry on bones of extinct large mammals from tar pits. Results on some samples of Glyptodon and Holmesina (extinct large mammals similar to armadillos) yielded ages of >25 and >21 ka, respectively. We also studied the radiocarbon ages of three different samples of bones from the extinct Cuban ground sloth, Parocnus bownii, which yielded dates ranging from 4960 ± 280 to 11 880 ± 420 yr BP. In order to remove the tar component pretreat the samples sufficiently to obtain reliable dates, we cleaned the samples by Soxhlet extraction in benzene. Resulting samples of collagenous material were often small

  10. Productivity of clay tailings from phosphate mining: 3. Grain crops

    International Nuclear Information System (INIS)

    Mislevy, P.; Blue, W.G.; Roessler, C.E.; Martin, F.G.

    1991-01-01

    A split-fold field experiment was conducted to study forage and grain yield, forage quality, plant nutrient concentrations, changes in soil nutrients, and 226 Ra contents of four grain crops in various rotations. The crop rotations (1) corn (Zea mays L. Jacques 247)-sunflower (Helianthus annuus L. Cargil 205), (2) sunflower-grain sorghum (Sorghum bicolor L, Moench Northrup King Savanna 5), (3) soybean (Glycine max L. Merr. Williams 80)-grain sorghum, and (4) grain sorghum-soybean (University of Florida V-1) were grown on a dry phosphatic clay with and without a 50-mm surface layer of quartz-sand tailings. Results show that corn and grain sorghum produced highest forage yields and highest grain yields per harvest, respectively. Soybean harvested for forage (Crop 1) contained the highest crude protein and in vitro organic matter digestibility. Concentrations of P, K, Ca, Mg, and Fe in most of the forages were adequate for the diets of beef cattle, while those of Mn, Cu and Zn were low. Mehlich I-extractable soil, Ca, and Mg were considered very high and changed little over the 4-yr production period. Application of 50 mm of sand tailings tended to increase Mehlich I-extractable P, Ca, Mn, Cu, Zn, and Fe. Radium-226 concentration in the forage of all grain crops averaged 8.5 Bq kg -1 , which was about 17 times higher than that in the grain of the same crops. Concentrations of 226 Ra in the forage and grain were 1.1% and 0.09% of the concentration in clay respectively. These data indicate that phosphatic clays can be a valuable resource for the production of corn and sorghum grain that contain low concentrations of 226 Ra

  11. Tail gut cyst.

    Science.gov (United States)

    Rao, G Mallikarjuna; Haricharan, P; Ramanujacharyulu, S; Reddy, K Lakshmi

    2002-01-01

    The tail gut is a blind extension of the hindgut into the tail fold just distal to the cloacal membrane. Remnants of this structure may form tail gut cyst. We report a 14-year-old girl with tail gut cyst that presented as acute abdomen. The patient recovered after cyst excision.

  12. Carbon dynamics, food web structure and reclamation strategies in Athabasca oil sands wetlands (CRFAW)

    International Nuclear Information System (INIS)

    Ciborowski, J.; Dixon, G.; Foote, L.; Liber, K.; Smits, J.

    2010-01-01

    This abstract provided details of the Carbon Dynamics, Food Web Structure and Reclamation Strategies in Athabasca Oil Sands Wetlands (CFRAW) program, a collaboration between oil sands industry partners and university laboratories. CFRAW researchers are investigating the effects of mine tailings and process waters on the development, health, and function of wetland communities in post-mining landscapes. The aim of the program is to accurately predict how quickly the reclaimed wetlands will approach conditions seen in reference wetland systems. The program is also examining the effects of hydrocarbons as a surrogate source of carbon after they are metabolized by bacteria. The biological uptake, pathways, and movement through the food web of materials used by the biota in constructed wetlands are also being studied. Flux estimates will be used to determine if wetlands amended with peat will maintain their productivity. A conceptual model of carbon pathways and budgets is also being developed.

  13. Modelling and design of undercarriage components of large-scale earthmoving equipment in tar sand operations

    Energy Technology Data Exchange (ETDEWEB)

    Szymanski, J.; Frimpong, S.; Sobieski, R. [Alberta Univ., Edmonton, AB (Canada). Centre for Advanced Energy and Minerals Research

    2004-07-01

    This presentation described the fundamental and applied research work which has been carried out at the University of Alberta's Centre for Advanced Energy and Minerals Research to improve the undercarriage elements of large scale earthmoving equipment used in oil sands mining operations. A new method has been developed to predict the optimum curvature and blade geometry of earth moving equipment such as bulldozers and motor graders. A mathematical relationship has been found to approximate the optimum blade shape for reducing cutting resistance and fill resistance. The equation is a function of blade geometry and soil properties. It is the first model that can mathematically optimize the shape of a blade on earth moving equipment. A significant saving in undercarriage components can be achieved from reducing the amount of cutting and filling resistance for this type of equipment working on different soils. A Sprocket Carrier Roller for a Tracked Vehicle was also invented to replace the conventional cylindrical carrier roller. The new sprocket type carrier roller offers greater support for the drive track and other components of the undercarriage assembly. A unique retaining pin assembly has also been designed to detach connecting disposable wear parts from earthmoving equipment. The retaining pin assembly is easy to assemble and disassemble and includes reusable parts. 13 figs.

  14. Intensive heat method for using non-segregate fine tailings for generating hot process water and stable solids that can support traffic

    Energy Technology Data Exchange (ETDEWEB)

    Betzer-Zilevitch, M. [Ex-Tar Technologies Inc., AB (Canada)

    2010-07-01

    This power point presentation described a method developed to extract energy from non-segregated fine tailings for generating hot process water. The method produced stable solids that were able to support traffic. Discharged non-segregated tailings passed through a zero liquid discharge direct contact steam generator (DCSG) and were then further treated and returned to the oil sands mine and bitumen extraction facility. A direct contact heat exchanger and condenser removed contaminates. Laboratory analyses confirmed that the DCSG condensate was toxic. Light organics were not destroyed. The method was then simulated in order to investigate the impact of pressure on performance. The study demonstrated that the method is both simple and robust. Non-segregated asphaltene-rich fine tailing streams can be used, and no changes to extraction, oil separation, or froth treatment equipment is needed. A cost benefit analysis was included. tabs., figs.

  15. ANALYSIS OF MEASURED AND MODELED SOLAR RADIATION AT THE TARS SOLAR HEATING PLANT IN DENMARK

    DEFF Research Database (Denmark)

    Tian, Zhiyong; Perers, Bengt; Furbo, Simon

    2017-01-01

    , such as solar radiation, inlet and outlet temperature for the solar collector field, flow rate and pressure, ambient temperature, Wind speed and wind direction were measured. Global horizontal radiation, direct normal irradiation (DNI) and total radiation on the tilted collector plane of the flat plate...... collector field have been measured in Tars solar heating plant. To determine the accuracy of modeled and measured solar radiation in Tars solar heating plant, monthly comparisons of measured and calculated radiation using 6 empirical models have been carried out. Comparisons of measured and modeled total......A novel combined solar heating plant with tracking parabolic trough collectors (PTC) and flat plate collectors (FPC) has been constructed and put into operation in Tars, 30 km north of Aalborg, Denmark in August 2015. To assess the operation performance of the plant, detailed parameters...

  16. Parallels between playbacks and Pleistocene tar seeps suggest sociality in an extinct sabretooth cat, Smilodon

    OpenAIRE

    Carbone, Chris; Maddox, Tom; Funston, Paul J.; Mills, Michael G.L.; Grether, Gregory F.; Van Valkenburgh, Blaire

    2008-01-01

    Inferences concerning the lives of extinct animals are difficult to obtain from the fossil record. Here we present a novel approach to the study of extinct carnivores, using a comparison between fossil records (n=3324) found in Late Pleistocene tar seeps at Rancho La Brea in North America and counts (n=4491) from playback experiments used to estimate carnivore abundance in Africa. Playbacks and tar seep deposits represent competitive, potentially dangerous encounters where multiple predators ...

  17. Traditional African Religions (TARs): on HIV/AIDS, health and ...

    African Journals Online (AJOL)

    This is because the moral guidance put forward by. African religions is underestimated; hence making HIV/AIDS more of a moral problem. Rethinking the dialogue with TARs, will help in setting appropriate means of enhancing health in a broad sense and living in human dignity in Africa. Mtafiti Mwafrika Vol. 15 2005: pp.

  18. Coal-tar-based pavement sealcoat and PAHs: implications for the environment, human health, and stormwater management.

    Science.gov (United States)

    Mahler, Barbara J; Metre, Peter C Van; Crane, Judy L; Watts, Alison W; Scoggins, Mateo; Williams, E Spencer

    2012-03-20

    Coal-tar-based sealcoat products, widely used in the central and eastern U.S. on parking lots, driveways, and even playgrounds, are typically 20-35% coal-tar pitch, a known human carcinogen that contains about 200 polycyclic aromatic hydrocarbon (PAH) compounds. Research continues to identify environmental compartments-including stormwater runoff, lake sediment, soil, house dust, and most recently, air-contaminated by PAHs from coal-tar-based sealcoat and to demonstrate potential risks to biological communities and human health. In many cases, the levels of contamination associated with sealed pavement are striking relative to levels near unsealed pavement: PAH concentrations in air over pavement with freshly applied coal-tar-based sealcoat, for example, were hundreds to thousands of times higher than those in air over unsealed pavement. Even a small amount of sealcoated pavement can be the dominant source of PAHs to sediment in stormwater-retention ponds; proper disposal of such PAH-contaminated sediment can be extremely costly. Several local governments, the District of Columbia, and the State of Washington have banned use of these products, and several national and regional hardware and home-improvement retailers have voluntarily ceased selling them.

  19. Coal-tar-based pavement sealcoat and PAHs: implications for the environment, human health, and stormwater management

    Science.gov (United States)

    Mahler, Barbara J.; Van Metre, Peter C.; Crane, Judy L.; Watts, Alison W.; Scoggins, Mateo; Williams, E. Spencer

    2012-01-01

    Coal-tar-based sealcoat products, widely used in the central and eastern U.S. on parking lots, driveways, and even playgrounds, are typically 20-35% coal-tar pitch, a known human carcinogen that contains about 200 polycyclic aromatic hydrocarbon (PAH) compounds. Research continues to identify environmental compartments—including stormwater runoff, lake sediment, soil, house dust, and most recently, air—contaminated by PAHs from coal-tar-based sealcoat and to demonstrate potential risks to biological communities and human health. In many cases, the levels of contamination associated with sealed pavement are striking relative to levels near unsealed pavement: PAH concentrations in air over pavement with freshly applied coal-tar-based sealcoat, for example, were hundreds to thousands of times higher than those in air over unsealed pavement. Even a small amount of sealcoated pavement can be the dominant source of PAHs to sediment in stormwater-retention ponds; proper disposal of such PAH-contaminated sediment can be extremely costly. Several local governments, the District of Columbia, and the State of Washington have banned use of these products, and several national and regional hardware and home-improvement retailers have voluntarily ceased selling them.

  20. Coal-tar pavement sealants might substantially increase children's PAH exposures

    Science.gov (United States)

    Williams, E. Spencer; Mahler, Barbara J.; Van Metre, Peter C.

    2012-01-01

    Dietary ingestion has been identified repeatedly as the primary route of human exposure to polycyclic aromatic hydrocarbons (PAHs), seven of which are classified as probable human carcinogens (B2 PAHs) by the U.S. EPA. Humans are exposed to PAHs through ingestion of cooked and uncooked foods, incidental ingestion of soil and dust, inhalation of ambient air, and absorption through skin. Although PAH sources are ubiquitous in the environment, one recently identified PAH source stands out: Coal-tar-based pavement sealant—a product applied to many parking lots, driveways, and even playgrounds primarily in the central, southern, and eastern U.S.—has PAH concentrations 100–1000 times greater than most other PAH sources. It was reported recently that PAH concentrations in house dust in residences adjacent to parking lots with coal-tar-based sealant were 25 times higher than in residences adjacent to unsealed asphalt parking lots.

  1. How do different cigarette design features influence the standard tar yields of popular cigarette brands sold in different countries?

    Science.gov (United States)

    O'Connor, R J; Hammond, D; McNeill, A; King, B; Kozlowski, L T; Giovino, G A; Cummings, K M

    2008-09-01

    To examine the associations among cigarette design features and tar yields of leading cigarette brands sold in the United States, Canada, Australia and the United Kingdom. Government reports and numbers listed on packs were used to obtain data on International Organization for Standardization (ISO)/Federal Trade Commission (FTC) yields for the tar of 172 cigarette varieties sold in the United States, Canada, Australia and the United Kingdom. We used standardised methods to measure the following 11 cigarette design parameters: filter ventilation, cigarette pressure drop, filter pressure drop, tobacco rod length, filter length, cigarette diameter, tipping paper length, tobacco weight, filter weight, rod density and filter density. Filter ventilation was found to be the predominant design feature accounting for the variations between brands in ISO/FTC tar yields in each of the four countries. After accounting for filter ventilation, design parameters such as overwrap length, tobacco weight and rod density played comparatively minor roles in determining tar yields. Variation in ISO/FTC tar yields are predicted by a limited set of cigarette design features, especially filter ventilation, suggesting that governments should consider mandatory disclosure of cigarette design parameters as part of comprehensive tobacco product regulations.

  2. Submarine sand ridges and sand waves in the eastern part of the China Sea

    Science.gov (United States)

    Wu, Ziyin; Li, Shoujun; Shang, Jihong; Zhou, Jieqiong; Zhao, Dineng; Liang, Yuyang

    2016-04-01

    Integrated with multi-beam and single-beam echo sounding data, as well as historical bathymetric data, submarine bathymetric maps of the eastern part of the China Sea, including the Bohai Sea, Huanghai Sea, and East China Sea, are constructed to systematically study submarine sand ridges and sand waves in the eastern part of the China Sea, combined with high-resolution seismic, sub-bottom profile and borehole data. Submarine sand ridges are extraordinarily developed in the eastern part of the China Sea, and 7 sand ridge areas can be divided from north to south, that is, the Laotieshan Channel sand ridge area in the Bohai Sea, the Korea Bay sand ridge area in the southern Huanghai Sea, the sand ridge area in the eastern Huanghai islands and the Huanghai Troughs, the Jianggang sand ridge area in the western Huanghai Sea, the sand ridge area in the East China Sea shelf, and the sand ridge and sand wave area in the Taiwan Strait and Taiwan Banks. The distribution area of the sand ridges and sand waves covers more than 450,000 km2, wherein ~10,000 km2 in the Bohai Bay, ~200,000 km2 in the Huanghai Sea, ~200,000 km2 in the East China Sea shelf, and ~40,000 km2 in the Taiwan Strait and Taiwan Banks, respectively. The great mass of sand ridges are distributed within water depth of 5-160 m, with a total length of over 160 km and a main width of 5-10 km. The inner structure of the sand ridges presents features of high-angle inclined beddings, with main lithology of sands, sand-mud alternations partly visible, and a small number of mud cores. Dating results indicate that the sand ridges in the eastern part of the China Sea are mainly developed in the Holocene. Sea-level variation dominates the sand ridge evolution in the eastern part of the China Sea since the LGM, and the sand ridges developed in the area of < 60m water depth are appeared in bad activity, meanwhile sand ridges with good activity are still developed in large scale.

  3. The tar sands of the USA : with permits now in hand, a Calgary company is a cash injection away from producing oil from America's first oilsands mine

    Energy Technology Data Exchange (ETDEWEB)

    Jaremko, D.

    2010-06-15

    A Canadian company has recently received approval to develop large oil sands mining operations in Utah. Earth Energy Resources is now raising the finances required to commercialize its operations in the state. Utah's oil sands reserves are currently estimated at between 20 to 32 billion barrels. However, the impacts of oil sands operations are of concern to some environmental groups, who worry that Utah will become a duplicate of Alberta's Athabasca region. The planned project is a 2000 barrel-per-day pilot project. Regulators in Utah have received negative responses from the public after advertising the potential project in local newspapers, and demonstrations have been held in the state's capital. Oil sands are already being developed at 2 installations in Utah, with the bitumen currently being sold as asphalt products. The state is also home to significant oil shale reserves. Operators in the region plan to design compact, well-contained mines in order to maintain transportability. 3 figs.

  4. Fresh tar (from biomass gasification) destruction with downstream catalysts: comparison of their intrinsic activity with a realistic kinetic model

    Energy Technology Data Exchange (ETDEWEB)

    Corella, J.; Narvaez, I.; Orio, A. [Complutense Univ. of Madrid (Spain). Dept. of Chemical Engineering

    1996-12-31

    A model for fresh tar destruction over catalysts placed downstream a biomass gasifier is presented. It includes the stoichio-metry and the calculation of the kinetic constants for the tar destruction. Catalysts studied include commercial Ni steam reforming catalysts and calcinated dolomites. Kinetic constants for tar destruction are calculated for several particle sizes, times- on-stream and temperatures of the catalyst and equivalence ratios in the gasifier. Such intrinsic kinetic constants allow a rigorous or scientific comparison of solids and conditions to be used in an advanced gasification process. (orig.) 4 refs.

  5. Fresh tar (from biomass gasification) destruction with downstream catalysts: comparison of their intrinsic activity with a realistic kinetic model

    Energy Technology Data Exchange (ETDEWEB)

    Corella, J; Narvaez, I; Orio, A [Complutense Univ. of Madrid (Spain). Dept. of Chemical Engineering

    1997-12-31

    A model for fresh tar destruction over catalysts placed downstream a biomass gasifier is presented. It includes the stoichio-metry and the calculation of the kinetic constants for the tar destruction. Catalysts studied include commercial Ni steam reforming catalysts and calcinated dolomites. Kinetic constants for tar destruction are calculated for several particle sizes, times- on-stream and temperatures of the catalyst and equivalence ratios in the gasifier. Such intrinsic kinetic constants allow a rigorous or scientific comparison of solids and conditions to be used in an advanced gasification process. (orig.) 4 refs.

  6. Revegetation of oil sands tailings. Growth improvement of silver-berry and buffalo-berry by inoculation with mycorrhizal fungi and N/sub 2/-fixing bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Visser, S.; Danielson, R.M.

    1988-01-01

    The ability of actinorhizal shrubs to tolerate inhospitable conditions while improving soil fertility and organic matter status has led to increased usage of these plants for land reclamation and amenity planting purposes. Silver-berry and buffalo-berry are two such shrubs being tested as potential candidates for the revegetation of the oil sands tailings in northeastern Alberta. Associated with the roots of silver-berry and buffalo-berry are two symbiants, the N/sub 2/-fixing actimomycete Frankia and the vesicular-arbuscular mycorrhizal (VAM) fungi. Numerous studies have demonstrated that, particularly in nutrient-limited conditions, mycorrhization and nodulation can result in significantly better plant performance as a consequence of improved N and P nutrition. It was found in this study that in Alberta, silver-berry and buffalo-berry are strictly VA mycorrhizal; that they are highly dependent on their symbiants for optimum growth; and that the VAM inoculum potential of both stockpiled and undisturbed muskeg peak is negligible, due to the absence of VAM hosts. Means to increase the inoculum potential of peat have been studied. The efficacy of inoculating seedlings grown in greenhouses with VAM and Frankia has been demonstrated. Overwinter mortality was higher for inoculated shrubs, but after one growing season, shoot-weights of silver-berry were 3 to 7 times greater than for uninoculated shrubs, and shoot weights of buffalo-berry were 3 to 5 times greater. 122 refs., 12 figs., 31 tabs.

  7. Bitumen extraction from oil sands ore-water slurry using CaO (lime) and or ozone

    Energy Technology Data Exchange (ETDEWEB)

    Babadagli, T. [Society of Petroleum Engineers, Canadian Section, Calgary, AB (Canada)]|[Alberta Univ., Edmonton, AB (Canada); Burkus, Z.; Moschopedis, S.E.; Ozum, B. [Apex Engineering Inc., Calvert City, KY (United States)

    2008-10-15

    Reductions in the surface and interfacial tensions in oil sands ore-water slurry systems improve bitumen extraction processes from oil sands ore structures and promote the attachment of air bubbles to liberated bitumen droplets. This study provided details of a non-caustic bitumen extraction process where oil sands slurries were conditioned by bitumen asphaltenes modified to act as surfactants. Oil sands ore-water slurry extraction processes were optimized by adding lime (CaO) and oxidizing bitumen asphaltenes with ozone (O{sub 3}). Experiments were conducted using oil sands ore and process water samples from Alberta. Extraction tests were performed to investigate the effects of various CaO and O{sub 3} dosages and treatment retention times on bitumen extraction efficiency on operating temperatures of 20, 35 and 50 degrees C. A Dean-Stark extraction apparatus was used to determine the amount of bitumen contained in the ore, froth, and in left-over tailings. Process water and release water chemistry were also monitored. Bitumen extraction efficiency was defined as the percentage of bitumen recovered in the resulting froth. Use of the slurries allowed high extraction efficiencies at a temperature of 35 degrees C. Energy consumption and carbon dioxide (CO{sub 2}) emissions were also reduced. The study showed that both additions resulted in significant improvements in bitumen extraction efficiency. Use of the technique also eliminated the accumulation of Na{sup +} ions in produced water. It was concluded that further tests are needed in order to commercialize the CaO and O{sub 3} based techniques. 14 refs., 1 tab., 4 figs.

  8. Changes in tar yields and cigarette design in samples of Chinese cigarettes, 2009 and 2012.

    Science.gov (United States)

    Schneller, Liane M; Zwierzchowski, Benjamin A; Caruso, Rosalie V; Li, Qiang; Yuan, Jiang; Fong, Geoffrey T; O'Connor, Richard J

    2015-11-01

    China is home to the greatest number of smokers as well as the greatest number of smoking-related deaths. An active and growing market of cigarettes marketed as 'light' or 'low tar' may keep health-concerned smokers from quitting, wrongly believing that such brands are less harmful. This study sought to observe changes in cigarette design characteristics and reported tar, nicotine and carbon monoxide (TNCO) levels in a sample of cigarette brands obtained in seven Chinese cities from 2009 to 2012. Cigarettes were purchased and shipped to Roswell Park Cancer Institute, where 91 pairs of packs were selected for physical cigarette design characteristic testing and recording of TNCO values. Data analysis was conducted using SPSS, and was initially characterised using descriptive statistics, correlations and generalised estimating equations to observe changes in brand varieties over time. Reported TNCO values on packs saw mean tar, nicotine and CO levels decrease from 2009 to 2012 by 7.9%, 4.5% and 6.0%, respectively. Ventilation was the only cigarette design feature that significantly changed over time (p<0.001), with an increase of 31.7%. Significant predictors of tar and CO yield overall were ventilation and per-cigarette tobacco weight, while for nicotine tobacco moisture was also an independent predictor of yield. The use of ventilation to decrease TNCO emissions is misleading smokers to believe that they are smoking a 'light/low' tar cigarette that is healthier, and is potentially forestalling the quitting behaviours that would begin to reduce the health burden of tobacco in China, and so should be prohibited. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  9. Uranium Mill Tailings Management

    International Nuclear Information System (INIS)

    Nelson, J.D.

    1982-01-01

    This book presents the papers given at the Fifth Symposium on Uranium Mill Tailings Management. Advances made with regard to uranium mill tailings management, environmental effects, regulations, and reclamation are reviewed. Topics considered include tailings management and design (e.g., the Uranium Mill Tailings Remedial Action Project, environmental standards for uranium mill tailings disposal), surface stabilization (e.g., the long-term stability of tailings, long-term rock durability), radiological aspects (e.g. the radioactive composition of airborne particulates), contaminant migration (e.g., chemical transport beneath a uranium mill tailings pile, the interaction of acidic leachate with soils), radon control and covers (e.g., radon emanation characteristics, designing surface covers for inactive uranium mill tailings), and seepage and liners (e.g., hydrologic observations, liner requirements)

  10. More tail lesions among undocked than tail docked pigs in a conventional herd

    DEFF Research Database (Denmark)

    Lahrmann, H. P.; Busch, M. E.; D'Eath, R. B.

    2017-01-01

    The vast majority of piglets reared in the European Union (EU) and worldwide is tail docked to reduce the risk of being tail bitten, even though EU animal welfare legislation bans routine tail docking. Many conventional herds experience low levels of tail biting among tail docked pigs, however...

  11. Application of passive sonar technology to mineral processing and oil sands applications : if you can measure it, you can manage it

    Energy Technology Data Exchange (ETDEWEB)

    O' Keefe, C.; Viega, J.; Fernald, M. [CiDRA Corp., Wallingford, CT (United States)

    2007-07-01

    SONAR-based flow and entrained air measurement instruments were described. This new class of industrial flow and compositional analyzers was developed by CiDRA to provide new measurement insight and quantifiable value to industrial process operators. Passive sonar array-based processing units have been installed worldwide in several industrial applications and are particularly suited for a wide range of mineral processing applications, including slurry flow rate measurement and fluid characterization. This paper also described the SONAR-based, clamp-on SONARtrac technology, a scalable platform that provides several other value added measurements and information such as speed of sound, entrained air/gas, gas hold-up, and velocity profile. Oil sands, tailings and bitumen slurries present considerable measurement challenges for in-line flow measurement devices in terms of measurement accuracy, reliability and maintenance. The sonar-based technology platform has been used in a variety of oil sands processes, hydrotransport, and minerals beneficiation applications. This paper described these applications with particular reference to difficult slurry flow measurement and control in the areas of comminution and flotation such as mill discharge, hydrocyclone feed/overflow, final concentrate, thickener discharge, and tailings. 5 refs., 4 tabs., 23 figs.

  12. Physicochemical and mineralogical characterization of Musina mine copper and New Union gold mine tailings: Implications for fabrication of beneficial geopolymeric construction materials

    Science.gov (United States)

    Gitari, M. W.; Akinyemi, S. A.; Thobakgale, R.; Ngoejana, P. C.; Ramugondo, L.; Matidza, M.; Mhlongo, S. E.; Dacosta, F. A.; Nemapate, N.

    2018-01-01

    The mining industries in South Africa generates huge amounts of mine waste that includes tailings; waste rocks and spoils. The tailings materials are dumped in surface impoundments that turn to be sources of hazards to the environment and the surrounding communities. The main environmental hazards posed by these tailings facilities are associated with their chemical constituents. Exposure to chemical constituents can occur through windblown dust, erosion to surface water bodies, inhalation by human beings and animals and through bioaccumulation and bio magnification by plants. Numerous un-rehabilitated tailings dumps exist in Limpopo province of South Africa. The communities found around these mines are constantly exposed to the environmental hazards posed by these tailing facilities. Development of a cost-effective technology that can beneficially utilize these tailings can reduce the environmental hazards and benefit the communities. This paper presents the initial evaluation of the copper and gold mine tailings in Limpopo, South Africa with a view to assessing the suitability of conversion into beneficial geopolymeric materials. Copper tailings leachates had alkaline pH (7.34-8.49) while the gold tailings had acidic pH. XRD confirmed presence of aluminosilicate minerals. Geochemical fractionation indicates that majority of the major and trace species are present in residual fraction. A significant amount of Ca, Cu and K was available in the mobile fraction and is expected to be released on tailings contacting aqueous solutions. Results from XRF indicates the tailings are rich in SiO2, Al2O3 and CaO which are the main ingredients in geopolymerization process. The SiO2/Al2O3 ratios indicates the tailings would require blending with Al2O3 rich feedstock for them to develop maximum strength. Moreover, the tailings have particle size in the range of fine sand which indicates potential application as aggregates in conventional brick manufacture.

  13. Perversities of Extreme Dependence and Unequal Growth in the TAR

    NARCIS (Netherlands)

    A.M. Fischer (Andrew Martín)

    2007-01-01

    textabstractThe official Chinese press recently came out with a series of articles reporting the latest statistics on the phenomenally rapid economic growth that has been taking place in the Tibet Autonomous Region (TAR) since the mid-1990s through sheer force of Central Government subsidies.

  14. PAHs underfoot: Contaminated dust from coal-tar sealcoated pavement is widespread in the United States

    Science.gov (United States)

    Van Metre, P.C.; Mahler, B.J.; Wilson, J.T.

    2009-01-01

    We reported in 2005 that runoff from parking lots treated with coal-tar-based sealcoat was a major source of polycyclic aromatic hydrocarbons (PAHs) to streams in Austin, Texas. Here we present new data from nine U. S. cities that show nationwide patterns in concentrations of PAHs associated with sealcoat Dust was swept from parking lots in six cities in the central and eastern U. S., where coal-tar-based sealcoat dominates use, and three cities in the western U. S., where asphalt-based sealcoat dominates use. For six central and eastern cities, median ?? PAH concentrations in dust from sealcoated and unsealcoated pavement are 2200 and 27 mg/kg, respectively. For three western cities, median ?? PAH concentrations in dust from sealcoated and unsealcoated pavement are similar and very low (2. 1 and 0. 8 mg/kg, respectively). Lakes in the central and eastern cities where pavement was sampled have bottom sediments with higher PAH concentrations than do those in the western cities relative to degree of urbanization. Bottom-sediment PAH assemblages are similar to those of sealcoated pavement dust regionally, implicating coal-tar-based sealcoat as a PAH source to the central and eastern lakes. Concentrations of benzo[a]pyrene in dust from coal-tar sealcoated pavement and adjacent soils greatly exceed generic soil screening levels, suggesting that research on human-health risk is warranted.

  15. PeaTAR1B: Characterization of a Second Type 1 Tyramine Receptor of the American Cockroach, Periplaneta americana.

    Science.gov (United States)

    Blenau, Wolfgang; Balfanz, Sabine; Baumann, Arnd

    2017-10-30

    The catecholamines norepinephrine and epinephrine regulate important physiological functions in vertebrates. In insects; these neuroactive substances are functionally replaced by the phenolamines octopamine and tyramine. Phenolamines activate specific guanine nucleotide-binding (G) protein-coupled receptors (GPCRs). Type 1 tyramine receptors are better activated by tyramine than by octopamine. In contrast; type 2 tyramine receptors are almost exclusively activated by tyramine. Functionally; activation of type 1 tyramine receptors leads to a decrease in the intracellular concentration of cAMP ([cAMP] i ) whereas type 2 tyramine receptors can mediate Ca 2+ signals or both Ca 2+ signals and effects on [cAMP] i . Here; we report that the American cockroach ( Periplaneta americana ) expresses a second type 1 tyramine receptor (PeaTAR1B) in addition to PeaTAR1A (previously called PeaTYR1). When heterologously expressed in flpTM cells; activation of PeaTAR1B by tyramine leads to a concentration-dependent decrease in [cAMP] i . Its activity can be blocked by a series of established antagonists. The functional characterization of two type 1 tyramine receptors from P. americana ; PeaTAR1A and PeaTAR1B; which respond to tyramine by changing cAMP levels; is a major step towards understanding the actions of tyramine in cockroach physiology and behavior; particularly in comparison to the effects of octopamine.

  16. PeaTAR1B: Characterization of a Second Type 1 Tyramine Receptor of the American Cockroach, Periplaneta americana

    Directory of Open Access Journals (Sweden)

    Wolfgang Blenau

    2017-10-01

    Full Text Available The catecholamines norepinephrine and epinephrine regulate important physiological functions in vertebrates. In insects; these neuroactive substances are functionally replaced by the phenolamines octopamine and tyramine. Phenolamines activate specific guanine nucleotide-binding (G protein-coupled receptors (GPCRs. Type 1 tyramine receptors are better activated by tyramine than by octopamine. In contrast; type 2 tyramine receptors are almost exclusively activated by tyramine. Functionally; activation of type 1 tyramine receptors leads to a decrease in the intracellular concentration of cAMP ([cAMP]i whereas type 2 tyramine receptors can mediate Ca2+ signals or both Ca2+ signals and effects on [cAMP]i. Here; we report that the American cockroach (Periplaneta americana expresses a second type 1 tyramine receptor (PeaTAR1B in addition to PeaTAR1A (previously called PeaTYR1. When heterologously expressed in flpTM cells; activation of PeaTAR1B by tyramine leads to a concentration-dependent decrease in [cAMP]i. Its activity can be blocked by a series of established antagonists. The functional characterization of two type 1 tyramine receptors from P. americana; PeaTAR1A and PeaTAR1B; which respond to tyramine by changing cAMP levels; is a major step towards understanding the actions of tyramine in cockroach physiology and behavior; particularly in comparison to the effects of octopamine.

  17. Fontainebleau Sand

    DEFF Research Database (Denmark)

    Leth, Caspar Thrane

    2006-01-01

    The report is a summary of results from laboratory tests in the geotechncial research group on Fontainebleau sand.......The report is a summary of results from laboratory tests in the geotechncial research group on Fontainebleau sand....

  18. Molecular identification of a yellow perch viral disease associated with exposure to oil sands process affected waters

    International Nuclear Information System (INIS)

    Hogan, N.; Van den Heuvel, M.; Phalen, L.

    2010-01-01

    Large volumes of tailings and process affected water are generated as a result of oil sand mining processes. This presentation discussed the safe incorporation of these wastes into the terrestrial and aquatic landscape. A study was conducted in which yellow perch were stocked into experimental ponds, namely Demonstration Pond and South Bison Pond, during the periods of 1995-1997 and 2008-2010. Demonstration Pond was comprised of mature fine tailings capped with natural surface water, while South Bison Pond was formed at a site surrounded by overburden or lean oil sands. Disease surveys were conducted at these experimental ponds and also at Mildred, Sucker, and Kimowin Lakes. External white nodular lesions, characteristic of lymphocystis disease were observed on perch at all sites except Kimowin Lake. The identity of the virus was confirmed by DNA extraction and PCR with genotype generic major capsid protein gene primers. The presence of lymphocystis disease virus in perch was confirmed through sequencing of PCR results. The viral genotype appeared to be different from any previously isolated viral genotype. During the course of the study, there was an increasing incidence of the disease at Demonstration Pond and a decreasing incidence at the South Bison Pond. The intensity of the disease was found to be proportional to the incidence, which was positively correlated with changes in naphthenic acid concentration.

  19. Calcipotriol versus coal tar: a prospective randomized study in stable plaque psoriasis

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, V.; Kaur, I.; Kumar, B. [Postgraduate Institute of Medicinal Education & Research, Chandigarh (India)

    2003-10-01

    Topical therapies are the first line of treatment for patients with stable plaque psoriasis (SPP) affecting a limited body surface area. Very few trials comparing newer agents, such as 0.005% topical calcipotriol, with conventional modes of therapy, such as coal tar ointment, have been reported. A prospective, right-left randomized, investigator-blinded study with a 12-week treatment period and an 8-week follow-up period was performed. It was found that 0.005% calcipotriol ointment produced a faster initial response and had better cosmetic acceptability in patients, although after a long period of treatment, i.e. 12 weeks, 5% coal tar ointment had comparable efficacy. There was no statistically significant difference in the relapse rates between the two modalities.

  20. Papers of the remediation technologies symposium 2005. CD-ROM ed.

    International Nuclear Information System (INIS)

    2005-01-01

    This conference was attended by over 500 delegates and provided an opportunity for industry, practitioners, researchers and regulators to discuss technical issues in environmental remediation research and recent innovations in soil and groundwater remediation. Sessions included presentations on in-situ, groundwater and surface water remediation. Issues concerning phytoremediation, natural attenuation, extraction and commercial redevelopment were examined. The aim of the conference was also to provide a forum for innovators in remediation to present new work. Topics included hydrocarbon and salt contamination; engineered soil cover for management of salt impacted sites; remediation and revegetation of tar sands composite tailings containing naphthenic acids; sorption of oil sands naphthenic acid mixtures; denitrification as a natural attenuation mechanism; sampling methodologies; variability assessments; stabilization treatment technologies; remediation of coal wastes; bioreactor landfills; well blowouts in Alberta; soil remediation in coarse gravelly soils; diesel-contaminated aquifers; gasoline spill remediation; soil vapour extraction systems; technological solutions for erosion control and water clarification; and cost-effective in-situ remediation strategies. Fifty-two technical presentations were given, of which 27 have been catalogued separately for inclusion in this database

  1. Papers of the remediation technologies symposium 2005. CD-ROM ed.

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This conference was attended by over 500 delegates and provided an opportunity for industry, practitioners, researchers and regulators to discuss technical issues in environmental remediation research and recent innovations in soil and groundwater remediation. Sessions included presentations on in-situ, groundwater and surface water remediation. Issues concerning phytoremediation, natural attenuation, extraction and commercial redevelopment were examined. The aim of the conference was also to provide a forum for innovators in remediation to present new work. Topics included hydrocarbon and salt contamination; engineered soil cover for management of salt impacted sites; remediation and revegetation of tar sands composite tailings containing naphthenic acids; sorption of oil sands naphthenic acid mixtures; denitrification as a natural attenuation mechanism; sampling methodologies; variability assessments; stabilization treatment technologies; remediation of coal wastes; bioreactor landfills; well blowouts in Alberta; soil remediation in coarse gravelly soils; diesel-contaminated aquifers; gasoline spill remediation; soil vapour extraction systems; technological solutions for erosion control and water clarification; and cost-effective in-situ remediation strategies. Fifty-two technical presentations were given, of which 27 have been catalogued separately for inclusion in this database. tabs., figs.

  2. Use of advanced chemical fingerprinting in PAH source identification and allocation at a coal tar processing site

    International Nuclear Information System (INIS)

    Brown, J.S.; Boehm, P.D.; Douglas, G.S.

    1995-01-01

    Advanced chemical fingerprinting analyses were used to determine source allocation at a former coal tar processing facility which had been converted to a petroleum recycling site. Soil samples from the site had high petroleum hydrocarbon concentrations and elevated levels of polynuclear aromatic hydrocarbons (PAH). Comparisons of PAH distributions were used to differentiate the coal tar hydrocarbons from the petroleum hydrocarbons in soil samples. A more specific technique was needed to accurately allocate the contribution of the two sources to the observed PAH contamination in the soil. Petroleum biomarkers (steranes and triterpanes) which are present in crude oils and many refined petroleum products but are absent in coal tar were used to quantitatively allocate the source of the PAH contamination based on the relative ratio of the PAH to the biomarkers in soil samples. Using the resulting coal tar/petroleum source ratio the contribution of petroleum to the overall PAH contamination at the site was calculated. A multivariate statistical technique (principal component analysis or PCA) was used to provide an independent validation of the source allocation. The results of the source allocation provided a foundation for the site clean-up and remediation costs

  3. Topical coal tar alone and in combination with oral methotrexate in management of psoriasis : a retrospective analysis

    Directory of Open Access Journals (Sweden)

    Prasad PVS

    1997-01-01

    Full Text Available Thirty five patients admitted with psoriasis were analysed. 16 patients received 20% crude coal tar and 19 patients received 20% crude coal tar along with methotrexate in a weekly oral schedule (15mg/wk. After 4 weeks of therapy there was total clearence in 52.6% of the patients with combination therapy, whereas only 12.5% of the patients with conventional therapy achieved this.

  4. Galaxies with long tails

    International Nuclear Information System (INIS)

    Schweizer, F.

    1978-01-01

    Two types of galaxies with long tails are described. The first occurs in pairs, each individual one having a long tail and the second occurs on its own with two tails. NGC 7252 shows several characteristics which one would expect of a merger: a pair of tidal tails despite the splendid isolation, a single nucleus, tail motions in opposite directions relative to the nucleus, and chaotic motions of a strangely looped main body. (C.F.)

  5. Attitudes of Dutch Pig Farmers Towards Tail Biting and Tail Docking

    OpenAIRE

    Bracke, M.B.M.; Lauwere, de, C.C.; Wind, S.M.M.; Zonderland, J.J.

    2013-01-01

    The Dutch policy objective of a fully sustainable livestock sector without mutilations by 2023 is not compatible with the routine practice of tail docking to minimize the risk of tail biting. To examine farmer attitudes towards docking, a telephone survey was conducted among 487 conventional and 33 organic Dutch pig farmers. “Biting” (of tails, ears, or limbs) was identified by the farmers as a main welfare problem in pig farming. About half of the farmers reported to have no tail biting prob...

  6. Study of Black Sand Particles from Sand Dunes in Badr, Saudi Arabia Using Electron Microscopy

    Directory of Open Access Journals (Sweden)

    Haider Abbas Khwaja

    2015-08-01

    Full Text Available Particulate air pollution is a health concern. This study determines the microscopic make-up of different varieties of sand particles collected at a sand dune site in Badr, Saudi Arabia in 2012. Three categories of sand were studied: black sand, white sand, and volcanic sand. The study used multiple high resolution electron microscopies to study the morphologies, emission source types, size, and elemental composition of the particles, and to evaluate the presence of surface “coatings or contaminants” deposited or transported by the black sand particles. White sand was comprised of natural coarse particles linked to wind-blown releases from crustal surfaces, weathering of igneous/metamorphic rock sources, and volcanic activities. Black sand particles exhibited different morphologies and microstructures (surface roughness compared with the white sand and volcanic sand. Morphological Scanning Electron Microscopy (SEM and Laser Scanning Microscopy (LSM analyses revealed that the black sand contained fine and ultrafine particles (50 to 500 nm ranges and was strongly magnetic, indicating the mineral magnetite or elemental iron. Aqueous extracts of black sands were acidic (pH = 5.0. Fe, C, O, Ti, Si, V, and S dominated the composition of black sand. Results suggest that carbon and other contaminant fine particles were produced by fossil-fuel combustion and industrial emissions in heavily industrialized areas of Haifa and Yanbu, and transported as cloud condensation nuclei to Douf Mountain. The suite of techniques used in this study has yielded an in-depth characterization of sand particles. Such information will be needed in future environmental, toxicological, epidemiological, and source apportionment studies.

  7. PAHs underfoot: contaminated dust from coal-tar sealcoated pavement is widespread in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Peter C. Van Metre; Barbara J. Mahler; Jennifer T. Wilson [U.S. Geological Survey, Austin, TX (USA)

    2009-01-15

    We reported in 2005 that runoff from parking lots treated with coal-tar-based sealcoat was a major source of polycyclic aromatic hydrocarbons (PAHs) to streams in Austin, Texas. Here we present new data from nine U.S. cities that show nationwide patterns in concentrations of {Sigma}PAHs associated with sealcoat. Dust was swept from parking lots in six cities in the central and eastern U.S., where coal-tar-based sealcoat dominates use, and three cities in the western U.S., where asphalt-based sealcoat dominates use. For six central and eastern cities, median SPAH concentrations in dust from sealcoated and unsealcoated pavement are 2200 and 27 mg/kg, respectively. For three western cities, median SPAH concentrations in dust from sealcoated and unsealcoated pavement are similar and very low (2.1 and 0.8 mg/kg, respectively). Lakes in the central and eastern cities where pavement was sampled have bottom sediments with higher PAH concentrations than do those in the western cities relative to degree of urbanization. Bottom-sediment PAH assemblages are similar to those of sealcoated pavement dust regionally, implicating coal-tar-based sealcoat as a PAH source to the central and eastern lakes. Concentrations of benzo(a)pyrene in dust from coal-tar sealcoated pavement and adjacent soils greatly exceed generic soil screening levels, suggesting that research on human-health risk is warranted. 30 refs., 4 figs., 2 tabs.

  8. Out on the tar sands mainline : mapping Enbridge's web of pipelines : a corporate profile of pipeline company Enbridge

    Energy Technology Data Exchange (ETDEWEB)

    Girard, R.; Davis, T.R. [Polaris Institute, Ottawa, ON (Canada)

    2010-05-15

    This document described Enbridge's operations, economic situation, political connections, and its social and environmental track record. It explored the social cost of operating refineries and pipelines in First Nations communities and the environment. It also raised concerns regarding future plans to open up Asian markets to oil sand crude via the Gateway pipeline. This profile included specific details on recurring pipeline leaks that have caused environmental damage; the ongoing expropriation of First Nations land; widespread political lobbying and influence in Canada and the United States; and interference in local community decision-making through financial contributions and projects. refs., tabs., figs.

  9. Criteria for selection of dolomites and catalysts for tar elimination from biomass gasification gas. Kinetic constants

    Energy Technology Data Exchange (ETDEWEB)

    Corella, J; Narvaez, I; Orio, A [Madrid Univ. (Spain). Dept. of Chem. Eng.

    1997-12-31

    Calcined dolomites and commercial steam reforming catalysts are used downstream biomass gasifiers for hot catalytic raw gas cleaning. To further compare these solids under a rigorous basis, a reaction network and a kinetic model are presented. The apparent kinetic constant for the tar reduction is here proposed as a basis of comparison. Tar sampling and analysis, and the units used for the space-time in the catalytic reactor affect the kinetic constants observed. (author) (2 refs.)

  10. Criteria for selection of dolomites and catalysts for tar elimination from biomass gasification gas. Kinetic constants

    Energy Technology Data Exchange (ETDEWEB)

    Corella, J.; Narvaez, I.; Orio, A. [Madrid Univ. (Spain). Dept. of Chem. Eng.

    1996-12-31

    Calcined dolomites and commercial steam reforming catalysts are used downstream biomass gasifiers for hot catalytic raw gas cleaning. To further compare these solids under a rigorous basis, a reaction network and a kinetic model are presented. The apparent kinetic constant for the tar reduction is here proposed as a basis of comparison. Tar sampling and analysis, and the units used for the space-time in the catalytic reactor affect the kinetic constants observed. (author) (2 refs.)

  11. Phase II, Title I engineering assessment of radioactive sands and residues, Lowman Site, Lowman Idaho

    Energy Technology Data Exchange (ETDEWEB)

    1977-12-01

    An engineering assessment was performed of the problems resulting from the existence of radioactive uranium sand residues at the Lowman, Idaho, site. Services normally include the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and other radium-contaminated materials, the evaluation of resulting investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas release from the 90,000 tons of sand residues at the Lowman site constitutes the most significant environmental impact, although external gamma radiation is also a factor. The two alternative actions presented are dike construction, fencing, and maintenance (Option I); and consolidation of the piles, addition of a 2-ft-thick stabilization cover, and on-site cleanup (Option II). Both options include remedial action at off-site structures. Cost estimates for the two options are $393,000 and $590,000.

  12. Phase II, Title I engineering assessment of radioactive sands and residues, Lowman Site, Lowman Idaho

    International Nuclear Information System (INIS)

    1977-12-01

    An engineering assessment was performed of the problems resulting from the existence of radioactive uranium sand residues at the Lowman, Idaho, site. Services normally include the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and other radium-contaminated materials, the evaluation of resulting investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas release from the 90,000 tons of sand residues at the Lowman site constitutes the most significant environmental impact, although external gamma radiation is also a factor. The two alternative actions presented are dike construction, fencing, and maintenance (Option I); and consolidation of the piles, addition of a 2-ft-thick stabilization cover, and on-site cleanup (Option II). Both options include remedial action at off-site structures. Cost estimates for the two options are $393,000 and $590,000

  13. The radiological impact of past and present practices of the mineral sands industry in Queensland

    International Nuclear Information System (INIS)

    Alexander, E.G.; Stewart, N.D.; Wallace, B.J.

    1993-01-01

    It is shown that the introduction of uniform Australian national Codes of Practice for radiation protection in the mining and milling of radioactive ores in the early 1980's has led to the mining and health regulatory authorities implementing the provisions of the Codes. Deficiencies involving dust and external gamma radiation levels in the mineral sands industry have led to various administrative and engineering controls being introduced to reduce the levels of radiation doses to employees well below 20 mSv/y limit. There are guidelines for screening the radioactivity of tailings released into the environment and some products for industrial use. Future activities by the regulatory authorities and industry will involve an optimisation of radiation protection, ongoing remedial programs, register of data about contaminated lands and assessments of the environmental, occupational and the public radiological impacts from downstream processing of mineral sands. The latter involves synthetic rutile, zircon flour, rare earth and refractory technologies. 7 refs., 1 tab., 1 fig

  14. A proteomic study of TAR-RNA binding protein (TRBP-associated factors

    Directory of Open Access Journals (Sweden)

    Chi Ya-Hui

    2011-02-01

    Full Text Available Abstract Background The human TAR RNA-binding protein, TRBP, was first identified and cloned based on its high affinity binding to the small hairpin trans-activation responsive (TAR RNA of HIV-1. TRBP has more recently been found to be a constituent of the RNA-induced silencing complex (RISC serving as a Dicer co-factor in the processing of the ~70 nucleotide pre-microRNAs(miRNAs to 21-25 nucleotide mature miRNAs. Findings Using co-immunoprecipitation and protein-identification by mass spectrometry, we characterized intracellular proteins that complex with TRBP. These interacting proteins include those that have been described to act in protein synthesis, RNA modifications and processing, DNA transcription, and cell proliferation. Conclusions Our findings provide a proteome of factors that may cooperate with TRBP in activities such as miRNA processing and in RNA interference by the RISC complex.

  15. Isolation of biosurfactant-producing bacteria from the Rancho La Brea Tar Pits.

    Science.gov (United States)

    Belcher, Richard W; Huynh, Kelvin V; Hoang, Timothy V; Crowley, David E

    2012-12-01

    This research was conducted to identify culturable surfactant-producing bacterial species that inhabit the 40,000-year-old natural asphalt seep at the Rancho La Brea Tar Pits in Los Angeles, CA. Using phenanthrene, monocyclic aromatic hydrocarbons, and tryptic soy broth as growth substrates, culturable bacteria from the tar pits yielded ten isolates, of which three species of gamma-proteobacteria produced biosurfactants that accumulated in spent culture medium. Partially purified biosurfactants produced by these strains lowered the surface tension of water from 70 to 35-55 mN/m and two of the biosurfactants produced 'dark halos' with the atomized oil assay, a phenomenon previously observed only with synthetic surfactants. Key findings include the isolation of culturable biosurfactant-producing bacteria that comprise a relatively small fraction of the petroleum-degrading community in the asphalt.

  16. The effects of oil sands wastewater on fish resulting from exposure to sub-lethal concentrations

    International Nuclear Information System (INIS)

    Birkholz, D.A.; Goudey, J.S.; Balch, G.C.; Nelson, L.R.; MacKinnon, M.

    1995-01-01

    Rainbow trout, Oncorhynchus mykiss, were exposed to sub-lethal concentrations of oil sands wastewater in flow through laboratory experiments as well as to artificial ponds containing sub-lethal concentrations of tailings pond water and fine tails in order to study the viability of the wet landscape remediation option. Large (200--300 g) fish were used for all the exposures in this preliminary study and the following data were collected: blood cell counts, sex hormone concentrations, sexual maturation, stress protein concentrations, PAH-metabolites in bile, condition factors, liver somatic indices, mixed function oxygenase induction, PAHs in muscle, external condition and the condition of internal organs. The data obtained from this study revealed no adverse effects upon fish during extended field exposures. Given similar exposure conditions in the release waters of a wet landscape reclamation, the data suggest that there may be no adverse effects upon fish, however, longer term studies, other indicator organisms and additional chronic tests should be conducted

  17. Bar-tailed

    NARCIS (Netherlands)

    Duijns, S.; Hidayati, N.A.; Piersma, T.

    2013-01-01

    Capsule Across the European wintering range Bar-tailed Godwits Limosa lapponica lapponica selected polychaete worms and especially Ragworms Hediste diversicolor, with differences between areas due to variations in prey availability.Aims To determine the diet of Bar-tailed Godwits across their

  18. TAIL ASYMPTOTICS OF LIGHT-TAILED WEIBULL-LIKE SUMS

    DEFF Research Database (Denmark)

    Asmussen, Soren; Hashorva, Enkelejd; Laub, Patrick J.

    2017-01-01

    We consider sums of n i.i.d. random variables with tails close to exp{-x(beta)} for some beta > 1. Asymptotics developed by Rootzen (1987) and Balkema, Kluppelberg, and Resnick (1993) are discussed from the point of view of tails rather than of densities, using a somewhat different angle...

  19. Cameco engineered tailings program: linking research with industrial processes for improved tailings performance

    International Nuclear Information System (INIS)

    Kotzer, T.; Hendry, M.J.

    2011-01-01

    The waste product from uranium mining and milling that generates the greatest public and regulatory concern is tailings. The tailings contain all of the mined material except uranium plus a host of processing reagents. These minerals and compounds have the potential to harm the local environment if not deposited in a fashion that is both geochemically and geotechnically stable. Environmental leadership impels Cameco Corporation to ensure that the methods used to dispose of tailings are at the forefront of best available technologies whereby tailings production results in a product with geotechnical and geochemical characteristics that minimize the environmental impact associated with long-term storage of this product. Cameco has developed an Engineered Tailings (ET) program to ensure optimization of long-term tailings performance and minimal impacts of elements of concern (EOCs) to the receiving environment, regardless of the ore being milled. Within this program chemical and physical performance of tailings from geochemical and geotechnical investigations and baseline environmental data, integrated with regulatory requirements and corporate commitments, will be used to evaluate and set criteria for mill- and tailings management facilities-based chemical and physical tailings characteristics, identify key knowledge gaps, prioritize areas of concern and implement appropriate responses. This paper provides an overview of the Engineered Tailings program, the research being conducted as part of the ET program, and how it links with present and future Cameco operations. (author)

  20. New generation expandable sand screens

    OpenAIRE

    Syltøy, Christer

    2014-01-01

    Master's thesis in Petroleum engineering This thesis aims to give a general insight into sand control and various sorts of sand control measures and applications of sand control tools. Special focus will be given to expandable sand screens – a technology which came about in the late 1990’s through the use of flexible, expandable tubulars as base pipe in sand screens. More specifically Darcy’s Hydraulic Endurance Screens, a compliant sand screen system using hydraulic activation, and the fu...