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Sample records for sands process-affected water

  1. Characterization of napthenic acids in oil sands process-affected waters using fluorescence technology

    International Nuclear Information System (INIS)

    Brown, L.; Alostaz, M.; Ulrich, A.

    2009-01-01

    Process-affected water from oil sands production plants presents a major environmental challenge to oil sands operators due to its toxicity to different organisms as well as its corrosiveness in refinery units. This abstract investigated the use of fluorescence excitation-emission matrices to detect and characterize changes in naphthenic acid in oil sands process-affected waters. Samples from oil sands production plants and storage ponds were tested. The study showed that oil sands naphthenic acids show characteristic fluorescence signatures when excited by ultraviolet light in the range of 260 to 350 mm. The signal was a unique attribute of the naphthenic acid molecule. Changes in the fluorescence signature can be used to determine chemical changes such as degradation or aging. It was concluded that the technology can be used as a non-invasive continuous water quality monitoring tool to increase process control in oil sands processing plants

  2. 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.

  3. 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.

  4. Rainbow trout (Oncorhynchus mykiss) detection, avoidance, and chemosensory effects of oil sands process-affected water.

    Science.gov (United States)

    Lari, Ebrahim; Pyle, Greg G

    2017-06-01

    Oil sands process-affected water (OSPW) - a byproduct of the oil sands industry in Northern Alberta, Canada - is currently stored in on-site tailings ponds. The goal of the present study was to investigate the interaction of OSPW with the olfactory system and olfactory-mediated behaviours of fish upon the first encounter with OSPW. The response of rainbow trout (Oncorhynchus mykiss) to different concentrations (0.1, 1, and 10%) of OSPW was studied using a choice maze and electro-olfactography (EOG), respectively. The results of the present study showed that rainbow trout are capable of detecting and avoiding OSPW at a concentration as low as 0.1%. Exposure to 1% OSPW impaired (i.e. reduced sensitivity) the olfactory response of rainbow trout to alarm and food cues within 5 min or less. The results of the present study demonstrated that fish could detect and avoid minute concentrations of OSPW. However, if fish were exposed to OSPW-contaminated water and unable to escape, their olfaction would be impaired. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Effects-Directed Analysis of Dissolved Organic Compounds in Oil Sands Process-Affected Water.

    Science.gov (United States)

    Morandi, Garrett D; Wiseman, Steve B; Pereira, Alberto; Mankidy, Rishikesh; Gault, Ian G M; Martin, Jonathan W; Giesy, John P

    2015-10-20

    Acute toxicity of oil sands process-affected water (OSPW) is caused by its complex mixture of bitumen-derived organics, but the specific chemical classes that are most toxic have not been demonstrated. Here, effects-directed analysis was used to determine the most acutely toxic chemical classes in OSPW collected from the world's first oil sands end-pit lake. Three sequential rounds of fractionation, chemical analysis (ultrahigh resolution mass spectrometry), and acute toxicity testing (96 h fathead minnow embryo lethality and 15 min Microtox bioassay) were conducted. Following primary fractionation, toxicity was primarily attributable to the neutral extractable fraction (F1-NE), containing 27% of original organics mass. In secondary fractionation, F1-NE was subfractionated by alkaline water washing, and toxicity was primarily isolated to the ionizable fraction (F2-NE2), containing 18.5% of the original organic mass. In the final round, chromatographic subfractionation of F2-NE2 resulted in two toxic fractions, with the most potent (F3-NE2a, 11% of original organic mass) containing predominantly naphthenic acids (O2(-)). The less-toxic fraction (F3-NE2b, 8% of original organic mass) contained predominantly nonacid species (O(+), O2(+), SO(+), NO(+)). Evidence supports naphthenic acids as among the most acutely toxic chemical classes in OSPW, but nonacidic species also contribute to acute toxicity of OSPW.

  6. Sulfate reducing bacteria and their activities in oil sands process-affected water biofilm

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hong; Yu, Tong, E-mail: tong.yu@ualberta.ca; Liu, Yang, E-mail: yang.liu@ualberta.ca

    2015-12-01

    Biofilm reactors were constructed to grow stratified multispecies biofilm in oil sands process-affected water (OSPW) supplemented with growth medium. The development of sulfate reducing bacteria (SRB) within the biofilm and the biofilm treatment of OSPW were evaluated. The community structure and potential activity of SRB in the biofilm were investigated with H{sub 2}S microsensor measurements, dsrB gene-based denaturing gradient gel electrophoresis (DGGE), and the real time quantitative polymerase chain reaction (qPCR). Multispecies biofilm with a thickness of 1000 μm was successfully developed on engineered biocarriers. H{sub 2}S production was observed in the deeper anoxic zone of the biofilm from around 750 μm to 1000 μm below the bulk water-biofilm interface, revealing sulfate reduction in the deeper zone of the stratified biofilm. The biofilm removed chemical oxygen demand (COD), sulfate, and nitrogen. The study expands current knowledge of biofilm treatment of OSPW and the function of anaerobic SRB in OSPW biofilm, and thus provides information for future bioreactor development in the reclamation of OSPW. - Graphical abstract: The development of sulfate reducing bacteria (SRB) within Oil Sands Process-affected Water (OSPW) biofilm and the biofilm treatment of OSPW were evaluated by Liu and coworkers. Combined microsensor and molecular biology techniques were utilized in this study. Their results demonstrated that multispecies biofilm with a thickness of 1000 μm was successfully developed on engineered biocarriers. H{sub 2}S production was observed in the deeper anoxic zone of the biofilm from around 750 μm to 1000 μm below the bulk water-biofilm interface, revealing sulfate reduction in the deeper zone of the biofilm. The biofilm removed chemical oxygen demand (COD), sulfate, and nitrogen. - Highlights: • Biofilm in oil sands wastewater was developed on engineered biocarriers. • Bacterial community and in situ activity of SRB were studied in the

  7. Sulfate reducing bacteria and their activities in oil sands process-affected water biofilm

    International Nuclear Information System (INIS)

    Liu, Hong; Yu, Tong; Liu, Yang

    2015-01-01

    Biofilm reactors were constructed to grow stratified multispecies biofilm in oil sands process-affected water (OSPW) supplemented with growth medium. The development of sulfate reducing bacteria (SRB) within the biofilm and the biofilm treatment of OSPW were evaluated. The community structure and potential activity of SRB in the biofilm were investigated with H 2 S microsensor measurements, dsrB gene-based denaturing gradient gel electrophoresis (DGGE), and the real time quantitative polymerase chain reaction (qPCR). Multispecies biofilm with a thickness of 1000 μm was successfully developed on engineered biocarriers. H 2 S production was observed in the deeper anoxic zone of the biofilm from around 750 μm to 1000 μm below the bulk water-biofilm interface, revealing sulfate reduction in the deeper zone of the stratified biofilm. The biofilm removed chemical oxygen demand (COD), sulfate, and nitrogen. The study expands current knowledge of biofilm treatment of OSPW and the function of anaerobic SRB in OSPW biofilm, and thus provides information for future bioreactor development in the reclamation of OSPW. - Graphical abstract: The development of sulfate reducing bacteria (SRB) within Oil Sands Process-affected Water (OSPW) biofilm and the biofilm treatment of OSPW were evaluated by Liu and coworkers. Combined microsensor and molecular biology techniques were utilized in this study. Their results demonstrated that multispecies biofilm with a thickness of 1000 μm was successfully developed on engineered biocarriers. H 2 S production was observed in the deeper anoxic zone of the biofilm from around 750 μm to 1000 μm below the bulk water-biofilm interface, revealing sulfate reduction in the deeper zone of the biofilm. The biofilm removed chemical oxygen demand (COD), sulfate, and nitrogen. - Highlights: • Biofilm in oil sands wastewater was developed on engineered biocarriers. • Bacterial community and in situ activity of SRB were studied in the biofilm.

  8. Isotopic and geochemical tracers for fingerprinting process-affected waters in the oil sands industry: a pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Gibson, J.J.; Birks, S.J.; Moncur, M.; Yi, Y.; Tattrie, K.; Jasechko, S.; Richardson, K.; Eby, P. [Alberta Innovates - Technology Futures (Canada)

    2011-04-15

    During 2009 and 2010, Alberta Innovates - Technology Futures carried out a pilot study for Alberta Environment to examine the possibility of labeling process affected water from oil sands operations with isotropic and geochemical tracers. For the study, 3 oil sands operators furnished logistical support and personnel, 39 samples were gathered and several isotope tracers were measured. In addition, geotechnical analyses were performed and the presence of organic compounds in the samples was scanned using Fourier transform ion cyclotron resonance mass spectrometry. Results showed that the selected tracers were able to label water sources in some locations, however they cannot be used as a universal method and a case by case approach needs to be adopted. This study pointed out that Fourier transform ion cyclotron resonance mass spectrometry is the best way to construct a dataset for use in identification of process affected waters.

  9. Compromised development and survival in amphibians in reclaimed wetlands' water containing oil sands process-affected material

    International Nuclear Information System (INIS)

    Smits, J.; Schock, D.

    2010-01-01

    When closing a mine, operators must comply with government regulations to ensure that the sites are ecologically sustainable to support endemic flora and fauna. Creating wetlands in order to age and detoxify oil sands process-affected materials (OSPM) is a common reclamation strategy. In this study, amphibians indigenous to the boreal forest ecosystem were examined to determine if they can complete their lifecycle in water from reclaimed wetlands. Wood frog (Lithobates sylvaticus) eggs were collected from a natural pond 60 km south of an oil sand mining site. Tadpoles were raised in 1 of 6 water treatments refreshed every two days. The 2 reference water treatments included aged tap water and water from natural wetlands. The remaining 4 water treatments were from research wetlands on Syncrude and Suncor lease sites. Of the 120 tadpoles raised per water treatment, there was no significant difference in growth, development, or survival rates between the aged tap water and reference wetland water, but the fastest growth, development, and highest survival rates occurred in the two reference groups. There was a pronounced difference among the 4 treatment groups from Suncor and Syncrude reclamation sites. Survival was high in 3 of the water treatments from Syncrude and Suncor sites, but development rates were considerably reduced. Tadpoles that do not metamorphose before winter do not survive. It was therefore concluded that delayed development in tadpoles poses a serious risk to population stability in OSPM-containing wetlands.

  10. 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.

  11. Granular activated carbon for simultaneous adsorption and biodegradation of toxic oil sands process-affected water organic compounds.

    Science.gov (United States)

    Islam, Md Shahinoor; Zhang, Yanyan; McPhedran, Kerry N; Liu, Yang; Gamal El-Din, Mohamed

    2015-04-01

    Naphthenic acids (NAs) released into oil sands process-affected water (OSPW) during bitumen processing in Northern Alberta are problematic for oil sands industries due to their toxicity in the environment and resistance to degradation during conventional wastewater treatment processes. Granular activated carbon (GAC) has shown to be an effective media in removing biopersistent organics from wastewater using a combination of adsorption and biodegradation removal mechanisms. A simultaneous GAC (0.4 g GAC/L) adsorption and biodegradation (combined treatment) study was used for the treatment of raw and ozonated OSPW. After 28 days of batch treatment, classical and oxidized NAs removals for raw OSPW were 93.3% and 73.7%, and for ozonated OSPW were 96.2% and 77.1%, respectively. Synergetic effects of the combined treatment process were observed in removals of COD, the acid extractable fraction, and oxidized NAs, which indicated enhanced biodegradation and bioregeneration in GAC biofilms. A bacteria copy number >10(8) copies/g GAC on GAC surfaces was found using quantitative real time polymerase chain reaction after treatment for both raw and ozonated OSPW. A Microtox(®) acute toxicity test (Vibrio fischeri) showed effective toxicity removal (>95.3%) for the combined treatments. Therefore, the simultaneous GAC adsorption and biodegradation treatment process is a promising technology for the elimination of toxic OSPW NAs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Elucidating mechanisms of toxic action of dissolved organic chemicals in oil sands process-affected water (OSPW).

    Science.gov (United States)

    Morandi, Garrett D; Wiseman, Steve B; Guan, Miao; Zhang, Xiaowei W; Martin, Jonathan W; Giesy, John P

    2017-11-01

    Oil sands process-affected water (OSPW) is generated during extraction of bitumen in the surface-mining oil sands industry in Alberta, Canada, and is acutely and chronically toxic to aquatic organisms. It is known that dissolved organic compounds in OSPW are responsible for most toxic effects, but knowledge of the specific mechanism(s) of toxicity, is limited. Using bioassay-based effects-directed analysis, the dissolved organic fraction of OSPW has previously been fractionated, ultimately producing refined samples of dissolved organic chemicals in OSPW, each with distinct chemical profiles. Using the Escherichia coli K-12 strain MG1655 gene reporter live cell array, the present study investigated relationships between toxic potencies of each fraction, expression of genes and characterization of chemicals in each of five acutely toxic and one non-toxic extract of OSPW derived by use of effects-directed analysis. Effects on expressions of genes related to response to oxidative stress, protein stress and DNA damage were indicative of exposure to acutely toxic extracts of OSPW. Additionally, six genes were uniquely responsive to acutely toxic extracts of OSPW. Evidence presented supports a role for sulphur- and nitrogen-containing chemical classes in the toxicity of extracts of OSPW. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Reproductive and health assessment of fathead minnows (Pimephales promelas) inhabiting a pond containing oil sands process-affected water

    International Nuclear Information System (INIS)

    Kavanagh, Richard J.; Frank, Richard A.; Solomon, Keith R.; Van Der Kraak, Glen

    2013-01-01

    Highlights: ► Fish were collected from a pond containing oil sands process-affected water (OSPW). ► They were compared to fish from two reference sites within the oil sands region. ► Differences in GSIs and tubercle numbers were observed in fish from the OSPW pond. ► Opercula, gills, and 11-KT concentrations also differed in fish from the OSPW pond. ► Black spot and tapeworms were not observed in any of the fish from the OSPW pond. -- Abstract: Previous laboratory based studies have shown that oil sands process-affected waters (OSPWs) containing high concentrations of naphthenic acids (>25 mg/l) have adverse effects on the reproductive physiology of fish. The purpose of this study was to assess the reproductive development and health of a wild population of fathead minnows (Pimephales promelas) inhabiting an OSPW pond that has moderate concentrations of naphthenic acids (∼10 mg/l). Fathead minnows were collected at various times during the period of 2006 through 2008 from Demonstration Pond (OSPW) located at Syncrude Canada Ltd., and two reference sites, Beaver Creek reservoir and Poplar Creek reservoir, which are all north of Fort McMurray, AB, Canada. Condition factor, gill histopathology, gonadosomatic indices, liver somatic indices, male secondary sexual characteristics, and plasma sex steroids were examined. Depending on the time of year that fathead minnows were collected, there were differences in the condition factor, gonadosomatic indices, liver somatic indices, and secondary sexual characteristics of fathead minnows (in males) from Demonstration Pond when compared to the fathead minnows from the reference sites. In comparison to reference fish, lower concentrations of 11-ketotestosterone were measured in the plasma of male fathead minnows collected from Demonstration Pond in June 2006 and July 2007. Black spot disease and Ligula intestinalis were prevalent in fathead minnows from the reference sites but were not observed in fathead minnows

  14. Reproductive and health assessment of fathead minnows (Pimephales promelas) inhabiting a pond containing oil sands process-affected water

    Energy Technology Data Exchange (ETDEWEB)

    Kavanagh, Richard J., E-mail: rkavanag@uoguelph.ca [Department of Integrative Biology, University of Guelph, Guelph, ON, Canada N1G 2W1 (Canada); Frank, Richard A.; Solomon, Keith R. [Centre for Toxicology, University of Guelph, Guelph, ON, Canada N1G 2W1 (Canada); Van Der Kraak, Glen [Department of Integrative Biology, University of Guelph, Guelph, ON, Canada N1G 2W1 (Canada)

    2013-04-15

    Highlights: ► Fish were collected from a pond containing oil sands process-affected water (OSPW). ► They were compared to fish from two reference sites within the oil sands region. ► Differences in GSIs and tubercle numbers were observed in fish from the OSPW pond. ► Opercula, gills, and 11-KT concentrations also differed in fish from the OSPW pond. ► Black spot and tapeworms were not observed in any of the fish from the OSPW pond. -- Abstract: Previous laboratory based studies have shown that oil sands process-affected waters (OSPWs) containing high concentrations of naphthenic acids (>25 mg/l) have adverse effects on the reproductive physiology of fish. The purpose of this study was to assess the reproductive development and health of a wild population of fathead minnows (Pimephales promelas) inhabiting an OSPW pond that has moderate concentrations of naphthenic acids (∼10 mg/l). Fathead minnows were collected at various times during the period of 2006 through 2008 from Demonstration Pond (OSPW) located at Syncrude Canada Ltd., and two reference sites, Beaver Creek reservoir and Poplar Creek reservoir, which are all north of Fort McMurray, AB, Canada. Condition factor, gill histopathology, gonadosomatic indices, liver somatic indices, male secondary sexual characteristics, and plasma sex steroids were examined. Depending on the time of year that fathead minnows were collected, there were differences in the condition factor, gonadosomatic indices, liver somatic indices, and secondary sexual characteristics of fathead minnows (in males) from Demonstration Pond when compared to the fathead minnows from the reference sites. In comparison to reference fish, lower concentrations of 11-ketotestosterone were measured in the plasma of male fathead minnows collected from Demonstration Pond in June 2006 and July 2007. Black spot disease and Ligula intestinalis were prevalent in fathead minnows from the reference sites but were not observed in fathead minnows

  15. Isotherm and kinetic studies on adsorption of oil sands process-affected water organic compounds using granular activated carbon.

    Science.gov (United States)

    Islam, Md Shahinoor; McPhedran, Kerry N; Messele, Selamawit A; Liu, Yang; Gamal El-Din, Mohamed

    2018-07-01

    The production of oil from oil sands in northern Alberta has led to the generation of large volumes of oil sands process-affected water (OSPW) that was reported to be toxic to aquatic and other living organisms. The toxicity of OSPW has been attributed to the complex nature of OSPW matrix including the inorganic and organic compounds primarily naphthenic acids (NAs: C n H 2n+Z O x ). In the present study, granular activated carbon (GAC) adsorption was investigated for its potential use to treat raw and ozonated OSPW. The results indicated that NA species removal increased with carbon number (n) for a fixed Z number; however, the NA species removal decreased with Z number for a fixed carbon number. The maximum adsorption capacities obtained from Langmuir adsorption isotherm based on acid-extractable fraction (AEF) and NAs were 98.5 mg and 60.9 mg AEF/g GAC and 60 mg and 37 mg NA/g GAC for raw and ozonated OSPW, respectively. It was found that the Freundlich isotherm model best fits the AEF and NA equilibrium data (r 2  ≥ 0.88). The adsorption kinetics showed that the pseudo-second order and intraparticle diffusion models were both appropriate in modeling the adsorption kinetics of AEF and NAs to GAC (r 2  ≥ 0.97). Although pore diffusion was the rate limiting step, film diffusion was still significant for assessing the rate of diffusion of NAs. This study could be helpful to model, design and optimize the adsorption treatment technologies of OSPW and to assess the performance of other adsorbents. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. A risk-based approach for identifying constituents of concern in oil sands process-affected water from the Athabasca Oil Sands region.

    Science.gov (United States)

    McQueen, Andrew D; Kinley, Ciera M; Hendrikse, Maas; Gaspari, Daniel P; Calomeni, Alyssa J; Iwinski, Kyla J; Castle, James W; Haakensen, Monique C; Peru, Kerry M; Headley, John V; Rodgers, John H

    2017-04-01

    Mining leases in the Athabasca Oil Sands (AOS) region produce large volumes of oil sands process-affected water (OSPW) containing constituents that limit beneficial uses and discharge into receiving systems. The aim of this research is to identify constituents of concern (COCs) in OSPW sourced from an active settling basin with the goal of providing a sound rational for developing mitigation strategies for using constructed treatment wetlands for COCs contained in OSPW. COCs were identified through several lines of evidence: 1) chemical and physical characterization of OSPW and comparisons with numeric water quality guidelines and toxicity endpoints, 2) measuring toxicity of OSPW using a taxonomic range of sentinel organisms (i.e. fish, aquatic invertebrates, and a macrophyte), 3) conducting process-based manipulations (PBMs) of OSPW to alter toxicity and inform treatment processes, and 4) discerning potential treatment pathways to mitigate ecological risks of OSPW based on identification of COCs, toxicological analyses, and PBM results. COCs identified in OSPW included organics (naphthenic acids [NAs], oil and grease [O/G]), metals/metalloids, and suspended solids. In terms of species sensitivities to undiluted OSPW, fish ≥ aquatic invertebrates > macrophytes. Bench-scale manipulations of the organic fractions of OSPW via PBMs (i.e. H 2 O 2 +UV 254 and granular activated charcoal treatments) eliminated toxicity to Ceriodaphnia dubia (7-8 d), in terms of mortality and reproduction. Results from this study provide critical information to inform mitigation strategies using passive or semi-passive treatment processes (e.g., constructed treatment wetlands) to mitigate ecological risks of OSPW to aquatic organisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Adsorption of acid-extractable organics from oil sands process-affected water onto biomass-based biochar: Metal content matters.

    Science.gov (United States)

    Bhuiyan, Tazul I; Tak, Jin K; Sessarego, Sebastian; Harfield, Don; Hill, Josephine M

    2017-02-01

    The impact of biochar properties on acid-extractable organics (AEO) adsorption from oil sands process-affected water (OSPW) was studied. Biochar from wheat straw with the highest ash content (14%) had the highest adsorption capacity (0.59 mg/g) followed by biochar from pulp mill sludge, switchgrass, mountain pine, hemp shives, and aspen wood. The adsorption capacity had no obvious trend with surface area, total pore volume, bulk polarity and aromaticity. The large impact of metal content was consistent with the carboxylates (i.e., naphthenate species) in the OSPW binding to the metals (mainly Al and Fe) on the carbon substrate. Although the capacity of biochar is still approximately two orders of magnitude lower than that of a commercial activated carbon, confirming the property (i.e., metal content) that most influenced AEO adsorption, may allow biochar to become competitive with activated carbon after normalizing for cost, especially if this cost includes environmental impacts. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Next-Generation Pyrosequencing Analysis of Microbial Biofilm Communities on Granular Activated Carbon in Treatment of Oil Sands Process-Affected Water

    Science.gov (United States)

    Islam, M. Shahinoor; Zhang, Yanyan; McPhedran, Kerry N.

    2015-01-01

    The development of biodegradation treatment processes for oil sands process-affected water (OSPW) has been progressing in recent years with the promising potential of biofilm reactors. Previously, the granular activated carbon (GAC) biofilm process was successfully employed for treatment of a large variety of recalcitrant organic compounds in domestic and industrial wastewaters. In this study, GAC biofilm microbial development and degradation efficiency were investigated for OSPW treatment by monitoring the biofilm growth on the GAC surface in raw and ozonated OSPW in batch bioreactors. The GAC biofilm community was characterized using a next-generation 16S rRNA gene pyrosequencing technique that revealed that the phylum Proteobacteria was dominant in both OSPW and biofilms, with further in-depth analysis showing higher abundances of Alpha- and Gammaproteobacteria sequences. Interestingly, many known polyaromatic hydrocarbon degraders, namely, Burkholderiales, Pseudomonadales, Bdellovibrionales, and Sphingomonadales, were observed in the GAC biofilm. Ozonation decreased the microbial diversity in planktonic OSPW but increased the microbial diversity in the GAC biofilms. Quantitative real-time PCR revealed similar bacterial gene copy numbers (>109 gene copies/g of GAC) for both raw and ozonated OSPW GAC biofilms. The observed rates of removal of naphthenic acids (NAs) over the 2-day experiments for the GAC biofilm treatments of raw and ozonated OSPW were 31% and 66%, respectively. Overall, a relatively low ozone dose (30 mg of O3/liter utilized) combined with GAC biofilm treatment significantly increased NA removal rates. The treatment of OSPW in bioreactors using GAC biofilms is a promising technology for the reduction of recalcitrant OSPW organic compounds. PMID:25841014

  19. Next-generation pyrosequencing analysis of microbial biofilm communities on granular activated carbon in treatment of oil sands process-affected water.

    Science.gov (United States)

    Islam, M Shahinoor; Zhang, Yanyan; McPhedran, Kerry N; Liu, Yang; Gamal El-Din, Mohamed

    2015-06-15

    The development of biodegradation treatment processes for oil sands process-affected water (OSPW) has been progressing in recent years with the promising potential of biofilm reactors. Previously, the granular activated carbon (GAC) biofilm process was successfully employed for treatment of a large variety of recalcitrant organic compounds in domestic and industrial wastewaters. In this study, GAC biofilm microbial development and degradation efficiency were investigated for OSPW treatment by monitoring the biofilm growth on the GAC surface in raw and ozonated OSPW in batch bioreactors. The GAC biofilm community was characterized using a next-generation 16S rRNA gene pyrosequencing technique that revealed that the phylum Proteobacteria was dominant in both OSPW and biofilms, with further in-depth analysis showing higher abundances of Alpha- and Gammaproteobacteria sequences. Interestingly, many known polyaromatic hydrocarbon degraders, namely, Burkholderiales, Pseudomonadales, Bdellovibrionales, and Sphingomonadales, were observed in the GAC biofilm. Ozonation decreased the microbial diversity in planktonic OSPW but increased the microbial diversity in the GAC biofilms. Quantitative real-time PCR revealed similar bacterial gene copy numbers (>10(9) gene copies/g of GAC) for both raw and ozonated OSPW GAC biofilms. The observed rates of removal of naphthenic acids (NAs) over the 2-day experiments for the GAC biofilm treatments of raw and ozonated OSPW were 31% and 66%, respectively. Overall, a relatively low ozone dose (30 mg of O3/liter utilized) combined with GAC biofilm treatment significantly increased NA removal rates. The treatment of OSPW in bioreactors using GAC biofilms is a promising technology for the reduction of recalcitrant OSPW organic compounds. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  20. Parallel factor analysis PARAFAC of process affected water

    Energy Technology Data Exchange (ETDEWEB)

    Ewanchuk, A.M.; Ulrich, A.C.; Sego, D. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering; Alostaz, M. [Thurber Engineering Ltd., Calgary, AB (Canada)

    2010-07-01

    A parallel factor analysis (PARAFAC) of oil sands process-affected water was presented. Naphthenic acids (NA) are traditionally described as monobasic carboxylic acids. Research has indicated that oil sands NA do not fit classical definitions of NA. Oil sands organic acids have toxic and corrosive properties. When analyzed by fluorescence technology, oil sands process-affected water displays a characteristic peak at 290 nm excitation and approximately 346 nm emission. In this study, a parallel factor analysis (PARAFAC) was used to decompose process-affected water multi-way data into components representing analytes, chemical compounds, and groups of compounds. Water samples from various oil sands operations were analyzed in order to obtain EEMs. The EEMs were then arranged into a large matrix in decreasing process-affected water content for PARAFAC. Data were divided into 5 components. A comparison with commercially prepared NA samples suggested that oil sands NA is fundamentally different. Further research is needed to determine what each of the 5 components represent. tabs., figs.

  1. The effect of oil sands process-affected water and model naphthenic acids on photosynthesis and growth in Emiliania huxleyi and Chlorella vulgaris.

    Science.gov (United States)

    Beddow, Jessica; Johnson, Richard J; Lawson, Tracy; Breckels, Mark N; Webster, Richard J; Smith, Ben E; Rowland, Steven J; Whitby, Corinne

    2016-02-01

    Naphthenic acids (NAs) are among the most toxic organic pollutants present in oil sands process waters (OSPW) and enter marine and freshwater environments through natural and anthropogenic sources. We investigated the effects of the acid extractable organic (AEO) fraction of OSPW and individual surrogate NAs, on maximum photosynthetic efficiency of photosystem II (PSII) (FV/FM) and cell growth in Emiliania huxleyi and Chlorella vulgaris as representative marine and freshwater phytoplankton. Whilst FV/FM in E. huxleyi and C. vulgaris was not inhibited by AEO, exposure to two surrogate NAs: (4'-n-butylphenyl)-4-butanoic acid (n-BPBA) and (4'-tert-butylphenyl)-4-butanoic acid (tert-BPBA), caused complete inhibition of FV/FM in E. huxleyi (≥10 mg L(-1)n-BPBA; ≥50 mg L(-1)tert-BPBA) but not in C. vulgaris. Growth rates and cell abundances in E. huxleyi were also reduced when exposed to ≥10 mg L(-1)n- and tert-BPBA; however, higher concentrations of n- and tert-BPBA (100 mg L(-1)) were required to reduce cell growth in C. vulgaris. AEO at ≥10 mg L(-1) stimulated E. huxleyi growth rate (p ≤ 0.002), yet had no apparent effect on C. vulgaris. In conclusion, E. huxleyi was generally more sensitive to NAs than C. vulgaris. This report provides a better understanding of the physiological responses of phytoplankton to NAs which will enable improved monitoring of NA pollution in aquatic ecosystems in the future. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. 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.

  3. Conditions and processes affecting sand resources at archeological sites in the Colorado River corridor below Glen Canyon Dam, Arizona

    Science.gov (United States)

    East, Amy E.; Collins, Brian D.; Sankey, Joel B.; Corbett, Skye C.; Fairley, Helen C.; Caster, Joshua J.

    2016-05-17

    This study examined links among fluvial, aeolian, and hillslope geomorphic processes that affect archeological sites and surrounding landscapes in the Colorado River corridor downstream from Glen Canyon Dam, Arizona. We assessed the potential for Colorado River sediment to enhance the preservation of river-corridor archeological resources through aeolian sand deposition or mitigation of gully erosion. By identifying locally prevailing wind directions, locations of modern sandbars, and likely aeolian-transport barriers, we determined that relatively few archeological sites are now ideally situated to receive aeolian sand supply from sandbars deposited by recent controlled floods. Whereas three-fourths of the 358 river-corridor archeological sites we examined include Colorado River sediment as an integral component of their geomorphic context, only 32 sites currently appear to have a high degree of connectivity (coupled interactions) between modern fluvial sandbars and sand-dominated landscapes downwind. This represents a substantial decrease from past decades, as determined by aerial-photograph analysis. Thus, we infer that recent controlled floods have had a limited, and declining, influence on archeological-site preservation.

  4. Water quality and processes affecting dissolved oxygen concentrations in the Blackwater River, Canaan Valley, West Virginia

    Science.gov (United States)

    Waldron, M.C.; Wiley, J.B.

    1996-01-01

    The water quality and environmental processes affecting dissolved oxygen were determined for the Blackwater River in Canaan Valley, West Virginia. Canaan Valley is oval-shaped (14 miles by 5 miles) and is located in the Allegheny Mountains at an average elevation of 3,200 feet above sea level. Tourism, population, and real estate development have increased in the past two decades. Most streams in Canaan Valley are a dilute calcium magnesium bicarbonate-type water. Streamwater typicaly was soft and low in alkalinity and dissolved solids. Maximum values for specific conductance, hardness, alkalinity, and dissolved solids occurred during low-flow periods when streamflow was at or near baseflow. Dissolved oxygen concentrations are most sensitive to processes affecting the rate of reaeration. The reaeration is affected by solubility (atmospheric pressure, water temperature, humidity, and cloud cover) and processes that determine stream turbulence (stream depth, width, velocity, and roughness). In the headwaters, photosynthetic dissolved oxygen production by benthic algae can result in supersaturated dissolved oxygen concentrations. In beaver pools, dissolved oxygen consumption from sediment oxygen demand and carbonaceous biochemical oxygen demand can result in dissolved oxygen deficits.

  5. Numerical simulation of sand jet in water

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-07-01

    A numerical simulation of sand jet in water was presented. The study involved a two-phase flow using two-phase turbulent jets. A literature review was also presented, including an experiment on particle laden air jet using laser doppler velocimetry (LDV); experiments on the effect of particle size and concentration on solid-gas jets; an experimental study of solid-liquid jets using particle image velocimetry (PIV) technique where mean velocity and fluctuations were measured; and an experimental study on solid-liquid jets using the laser doppler anemometry (LDA) technique measuring both water axial and radial velocities. Other literature review results included a photographic study of sand jets in water; a comparison of many two-phase turbulent flow; and direct numerical simulation and large-eddy simulation to study the effect of particle in gas jet flow. The mathematical model and experimental setup were also included in the presentation along with simulation results for sand jets, concentration, and kinetic energy. The presentation concluded with some proposed future studies including numerical simulation of slurry jets in water and numerical simulation of slurry jets in MFT. tabs., figs.

  6. Application of TIE's in assessing toxicity associated with oil sands process waters

    International Nuclear Information System (INIS)

    MacKinnon, M.

    1998-01-01

    The hot water digestion process which separates bitumen from oil sands produces large volumes of process-affected waters which are extremely toxic to aquatic organisms. At Syncrude Canada's northeastern Alberta plant, the toxic waters are contained on the site and none are discharged. Organic acids, hydrocarbons and salts are leached into the tailings waters. A toxicity identification evaluation (TIE) test was used to confirm the main contributors to the acute toxicity in these waters. A battery bioassay approach as well as field and laboratory testing was used to understand the source, pathway and duration of the toxicity. Bioassays helped in developing ways in which to mitigate toxicity issues in both reclamation and operational waters. It was demonstrated that natural bioremediation of process-affected waters can reduce acute and chronic toxicity. The long term reclamation impacts of these waters has yet to be determined

  7. 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

  8. 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.

  9. Key parameters and processes affecting the re-establishment of eelgrass in estuaries and coastal water

    DEFF Research Database (Denmark)

    Canal Vergés, Paula

    and sediment trapping. In the last decades seagrass, in general and eelgrass (Zostera marina) in particular, have been heavily reduced, primarily due to a generalized euthrophication of the coastal waters. In Denmark, a numerous efforts on nutrient reduction and improvement on coastal water quality have been....... As a result it was proven that macroalgae generated SPM affected the light climate by dampening greatly the light availability at the sea bed in shallow coastal waters. An agent based model to simulate opportunistic and slower growing macroalgae species transport in Odense fjord was created. In this model......Seagrass are considered engineering species, and as such, provide numerous “ecosystem functions, services and goods”. Among them, seagrass systems offers structural functionality, shelter and food for a diverse trophic chain, high productivity, slow nutrient turnover, reduced hydrodynamic forcing...

  10. Natural and anthropogenic sources and processes affecting water chemistry in two South Korean streams

    International Nuclear Information System (INIS)

    Shin, Woo-Jin; Ryu, Jong-Sik; Mayer, Bernhard; Lee, Kwang-Sik; Lee, Sin-Woo

    2014-01-01

    Acid mine drainage (AMD) in a watershed provides potential sources of pollutants for surface and subsurface waters that can deteriorate water quality. Between March and early August 2011, water samples were collected from two streams in South Korea, one dominantly draining a watershed with carbonate bedrock affected by coal mines and another draining a watershed with silicate bedrock and a relatively undisturbed catchment area. The objective of the study was to identify the sources and processes controlling water chemistry, which was dependent on bedrock and land use. In the Odae stream (OS), the stream in the silicate-dominated catchment, Ca, Na, and HCO 3 were the dominant ions and total dissolved solids (TDS) was low (26.1–165 mg/L). In the Jijang stream (JS), in the carbonate-dominated watershed, TDS (224–434 mg/L) and ion concentrations were typically higher, and Ca and SO 4 were the dominant ions due to carbonate weathering and oxidation of pyrite exposed at coal mines. Dual isotopic compositions of sulfate (δ 34 S SO4 and δ 18 O SO4 ) verified that the SO 4 in JS is derived mainly from sulfide mineral oxidation in coal mines. Cl in JS was highest upstream and decreased progressively downstream, which implies that pollutants from recreational facilities in the uppermost part of the catchment are the major source governing Cl concentrations within the discharge basin. Dual isotopic compositions of nitrate (δ 15 N NO3 and δ 18 O NO3 ) indicated that NO 3 in JS is attributable to nitrification of soil organic matter but that NO 3 in OS is derived mostly from manure. Additionally, the contributions of potential anthropogenic sources to the two streams were estimated in more detail by using a plot of δ 34 S SO4 and δ 15 N NO3 . This study suggests that the dual isotope approach for sulfate and nitrate is an excellent additional tool for elucidating the sources and processes controlling the water chemistry of streams draining watersheds having different

  11. Relationships between sand and water quality at recreational beaches.

    Science.gov (United States)

    Phillips, Matthew C; Solo-Gabriele, Helena M; Piggot, Alan M; Klaus, James S; Zhang, Yifan

    2011-12-15

    Enterococci are used to assess the risk of negative human health impacts from recreational waters. Studies have shown sustained populations of enterococci within sediments of beaches but comprehensive surveys of multiple tidal zones on beaches in a regional area and their relationship to beach management decisions are limited. We sampled three tidal zones on eight South Florida beaches in Miami-Dade and Broward counties and found that enterococci were ubiquitous within South Florida beach sands although their levels varied greatly both among the beaches and between the supratidal, intertidal and subtidal zones. The supratidal sands consistently had significantly higher (p sand) than the other two zones. Levels of enterococci within the subtidal sand correlated with the average level of enterococci in the water (CFU/100mL) for the season during which samples were collected (r(s) = 0.73). The average sand enterococci content over all the zones on each beach correlated with the average water enterococci levels of the year prior to sand samplings (r(s) = 0.64) as well as the average water enterococci levels for the month after sand samplings (r(s) = 0.54). Results indicate a connection between levels of enterococci in beach water and sands throughout South Florida's beaches and suggest that the sands are one of the predominant reservoirs of enterococci impacting beach water quality. As a result, beaches with lower levels of enterococci in the sand had fewer exceedences relative to beaches with higher levels of sand enterococci. More research should focus on evaluating beach sand quality as a means to predict and regulate marine recreational water quality. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Natural and anthropogenic sources and processes affecting water chemistry in two South Korean streams

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Woo-Jin [Division of Earth and Environmental Sciences, Korea Basic Science Institute, Cheongwon-gun, Chungbuk 363-883 (Korea, Republic of); Department of Geoscience, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Ryu, Jong-Sik [Division of Earth and Environmental Sciences, Korea Basic Science Institute, Cheongwon-gun, Chungbuk 363-883 (Korea, Republic of); Mayer, Bernhard [Department of Geoscience, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Lee, Kwang-Sik, E-mail: kslee@kbsi.re.kr [Division of Earth and Environmental Sciences, Korea Basic Science Institute, Cheongwon-gun, Chungbuk 363-883 (Korea, Republic of); Lee, Sin-Woo [Division of Earth and Environmental Sciences, Korea Basic Science Institute, Cheongwon-gun, Chungbuk 363-883 (Korea, Republic of); Department of Geology, Chungnam National University, Yuseong-gu, Daejeon 305-764 (Korea, Republic of)

    2014-07-01

    Acid mine drainage (AMD) in a watershed provides potential sources of pollutants for surface and subsurface waters that can deteriorate water quality. Between March and early August 2011, water samples were collected from two streams in South Korea, one dominantly draining a watershed with carbonate bedrock affected by coal mines and another draining a watershed with silicate bedrock and a relatively undisturbed catchment area. The objective of the study was to identify the sources and processes controlling water chemistry, which was dependent on bedrock and land use. In the Odae stream (OS), the stream in the silicate-dominated catchment, Ca, Na, and HCO{sub 3} were the dominant ions and total dissolved solids (TDS) was low (26.1–165 mg/L). In the Jijang stream (JS), in the carbonate-dominated watershed, TDS (224–434 mg/L) and ion concentrations were typically higher, and Ca and SO{sub 4} were the dominant ions due to carbonate weathering and oxidation of pyrite exposed at coal mines. Dual isotopic compositions of sulfate (δ{sup 34}S{sub SO4} and δ{sup 18}O{sub SO4}) verified that the SO{sub 4} in JS is derived mainly from sulfide mineral oxidation in coal mines. Cl in JS was highest upstream and decreased progressively downstream, which implies that pollutants from recreational facilities in the uppermost part of the catchment are the major source governing Cl concentrations within the discharge basin. Dual isotopic compositions of nitrate (δ{sup 15}N{sub NO3} and δ{sup 18}O{sub NO3}) indicated that NO{sub 3} in JS is attributable to nitrification of soil organic matter but that NO{sub 3} in OS is derived mostly from manure. Additionally, the contributions of potential anthropogenic sources to the two streams were estimated in more detail by using a plot of δ{sup 34}S{sub SO4} and δ{sup 15}N{sub NO3}. This study suggests that the dual isotope approach for sulfate and nitrate is an excellent additional tool for elucidating the sources and processes

  13. Sustainable water management in Alberta's oil sands

    Energy Technology Data Exchange (ETDEWEB)

    Byers, Bill; Usher, Robyn; Roach, Andrea [CH2M HILL, Englewood, CO (United States); Lambert, Gord; Kotecha, Prit [Suncor Energy Inc., Calgary (Canada)

    2012-07-01

    The Canadian Association of Petroleum Producers forecast published in 2011 predicts that oil production from oil sands will increase by 50% in the next 3 years and double by 2020. This rate of growth will result in significant pressure on water resources; water use per barrel of oil sands production is comparable to other energy resources - about 2.5 barrels of fresh water per barrel of oil produced are used by mining operations and 0.5 barrels by in-situ operations. Suncor Energy Inc. (Suncor) was the first company to develop the oil sands in northern Alberta and holds one of the largest oil sands positions in Canada. In 2010, Suncor announced plans to increase production to more than 1 million barrels of oil equivalent per day by 2020, which it plans to achieve through oil sands production growth of approximately 10% per year. Because water supply and potential impacts to water quality are critical to its future growth, in 2010-2011 Suncor conducted a risk assessment to identify water-related business risks related to its northern Alberta operations. The assessment identified more than 20 high level business risks in strategic water risk areas including water supply, water reuse, storm water management, groundwater, waste management and river water return. The risk assessment results prompted development of a strategic roadmap to guide water stewardship across Suncor's regional operations. The roadmap describes goals, objectives, and specific activities for each of six key water risk areas, and informs prioritization and selection of prospective water management activities. Suncor is not only exploring water within its own boundaries, but is also collaborating with other oil sands producers to explore ways of integrating its water systems through industry consortia; Suncor is a member of the Oil Sands Leadership Initiative and of the recently formed Canadian Oil Sands Innovation Alliance, among others. (author)

  14. Some processes affecting the mobility of thorium in natural ground waters

    International Nuclear Information System (INIS)

    Oesthols, E.

    1994-04-01

    Thorium is a useful model element for tetravalent actinides such as U(IV), Pu(IV) and Np(IV) which are important constituents of spent nuclear fuel. Thorium is also an important tracer element for particle pathways in natural environments. In order to correctly model the transport of Th in the environment, it is important to have quantitative models for processes that effect its mobility. Some of these processes have been experimentally investigated in laboratory studies, and interpreted with quantitative models where possible. The carbonate complexation in aqueous solution of Th has been investigated through solubility studies of ThO 2 in carbonate media. It is shown, that thorium carbonate complexes are likely to be predominant in many natural waters. They also increase solubility of the oxide significantly, and hence the mobility of Th. Carbonate also increases the dissolution rate of thorium oxide. This effect will only be important in environments with a pH and total carbonate alkalinity higher than those of most natural aquatic environments. Solubility studies of thorium oxide in phosphate media show that phosphate does not significantly increase the mobility of Th in aqueous media. The presence of phosphate may cause the precipitation of sparingly soluble thorium phosphates which will decrease the mobility of Th. The pentahydroxo complex for Th is shown to be significant up to pH 13. Potentiometric studies of Th sorption on amorphous colloidal silica indicate, that pure aluminosilicates will probably not be efficient scavengers of tetravalent actinides above pH values of approximately 6. In neutral to alkaline solutions, iron (hydr)oxides are likely to be the predominant sorbents. Th binds to the silica surface through corner-sharing bonds, where Th and Si share one, but not more oxygen atoms. 72 refs

  15. Removal method of radium in mine water by filter sand

    International Nuclear Information System (INIS)

    Taki, Tomihiro; Naganuma, Masaki

    2003-01-01

    Trace radium is contained in mine water from the old mine road in Ningyo-Toge Environmental Engineering Center, JNC. We observed that filter sand with hydrated manganese oxide adsorbed radium in the mine water safely for long time. The removal method of radium by filter sand cladding with hydrated manganese oxide was studied. The results showed that radium was removed continuously and last for a long time from mine water with sodium hypochlorite solution by passing through the filter sand cladding with hydrated manganese. Only sodium hypochlorite solution was used. When excess of it was added, residue chlorine was used as chlorine disinfection. Filter sand cladding with hydrated manganese on the market can remove radium in the mine water. The removal efficiency of radium is the same as the radium coprecipitation method added with barium chloride. The cost is much lower than the ordinary methods. Amount of waste decreased to about 1/20 of the coprecipitation method. (S.Y.)

  16. A Simple Slow-Sand Filter for Drinking Water Purification

    Directory of Open Access Journals (Sweden)

    K. O. Yusuf

    2017-04-01

    Full Text Available Water-borne diseases are commonly encountered when pathogen-contaminated water is consumed. In rural areas, water is usually obtained from ponds, open shallow wells, streams and rain water during rainy season. Rain water is often contaminated by pathogens due to unhygienic of physical and chemical conditions of the roofs thereby making it unsafe for consumption. A simple slow sand filter mechanism was designed and fabricated for purification of water in rural areas where electricity is not available to power water purification devices. Rain water samples were collected from aluminum roof, galvanized roof and thatched roof. The waters samples were allowed to flow through the slow sand filter. The values of turbidity, total dissolved solids, calcium, nitrite, faecal coliform and total coliform from unfiltered water through thatched roof were 0.92 NTU, 27.23 mg/l, 6 mg/l, 0.16 mg/l, 5cfu/100ml and 6.0 cfu/100ml, respectively while the corresponding values for slow sand filter from thatched roof were 0.01 NTU, 0.23 mg/l, 2.5 mg/l, 0.1 mg/l, 0 cfu/100ml and 0 cfu/100ml, respectively. The values of turbidity, total dissolved solid, nitrite, calcium, faecal coliform and total coliform from unfiltered water for aluminum roof were 0.82 NTU, 23.68 mg/l, 2.70 mg/l, 1.0 mg/l, 4 cfu/100ml and 4cfu/100ml, respectively while the corresponding values for slow sand filter were 0.01 NTU, 0.16 mg/l, 0.57 mg/l, 0.2 mg/l, 0 cfu/100ml and 0 cfu/100ml, respectively. The values obtained for galvanized roof were also satisfactory. The slow sand filter is recommended for used in rural areas for water purification to prevent risk of water-borne diseases.

  17. Water quality and bathymetry of Sand Lake, Anchorage, Alaska

    Science.gov (United States)

    Donaldson, Donald E.

    1976-01-01

    Sand Lake, a dimictic lowland lake in Anchorage, Alaska, has recently become as urban lake. Analyses indicate that the lake is oligotrophic, having low dissolved solids and nutrient concentrations. Snowmelt runoff from an adjacent residential area, however, has a dissolved-solids concentration 10 times that of the main body of Sand Lake. Lead concentrations in the runoff exceed known values from other water in the ANchorage area, including water samples taken beneath landfills. The volume of the snowmelt runoff has not been measured. The data presented can be used as a baseline for water-resource management. (Woodard-USGS)

  18. White Sands Missile Range 2011 Drinking Water Quality Report

    Science.gov (United States)

    2012-01-01

    acerca de su agua potable . Haga que alguien lo traduzca para usted, o hable con alguien que lo entienda. Main Post White Sands Missile Range 2011...standards. What is This Water Quality Report? Este informe contiene informacion importante acerca de su agua potable . Haga que alguien lo traduzca

  19. Radon diffusion studies in air, gravel, sand, soil and water

    International Nuclear Information System (INIS)

    Singh, B.; Singh, S.; Virk, H.S.

    1993-01-01

    Radon isotopes are practically inert and have properties of gases under conditions of geological interest. During their brief lives their atoms are capable of moving from sites of their generation. Radon diffusion studies were carried out in air, gravel, sand, soil and water using silicon diffused junction electronic detector, Alphameter-400. Diffusion constant and diffusion length is calculated for all these materials. (author)

  20. Application of Self Cleaning Rapid Sand Filter in Water Treatment

    Directory of Open Access Journals (Sweden)

    Ali Reza Rahmani

    2005-08-01

    Full Text Available Rapid sand filter is one of the most important units in the water treatment plants. It has some difficulties in operation such as backwashing. For the solving of this problem a rapid sand filter has designed and built with the self-cleaning backwashing system. This system consist of 3 main constituents; one galvanized siphon and two galvanized steel tanks. One of them is used for filtration and the other used for the storage of filtrated water in elevation for backwashing the system. Water enter from upside of the filter through the inlet pipe, and collected from the under drainage pipe. Then filter water conduct to the storage tank and exit from outlet pipe. In the beginning, the head loss was low, but because of bed clogging by suspended solids, it increases gradually to the designed head loss (1.2m. Then the system is outed of the service automatically and the backwash is began. The main data for the design of system selected from the hydraulic rules of siphons and rapid sand filter criteria. After essential calculations it was constructed and was started operation. For the hydraulic studies a known volume of storage tank was selected and the time needed for the fill (in filtration stage and empty (in backwash stage of water volume with volumetric method were measured. In hydraulic studies the filter surface rate (SOR was selected about 5-7.5m3/m2/hr (1.39-2.08 lit/sec and the flow of water in siphon, during the backwashing was measured 8.7 lit/sec. It can be seen that the siphon passes 4-6 times the inlet raw water thus a negative pressure will created in the siphon which causes the water above the sand bed to be discharged automatically and rinse water from elevated tank flow under the sand bed and back wash it. So according to this study self cleaning rapid sand filter is very useful for water filtration, especially in small population community. The construction of system is rapid, simple and economic.

  1. Successful water management for the oil sands industry

    International Nuclear Information System (INIS)

    Braun, B.

    2003-01-01

    Water is a key requirement to produce oil from thermal oil sands projects. Historically, water was considered as a renewable resource that could be used when necessary. Water use is currently examined in a wider context. Canadian Natural Resources Limited has used fresh water for thermal projects in the past, including its thermal operations at Primrose and Wolf Lake. However, technical advancements have made it possible to use recycled water. This allows companies to survive within their licenses while increasing production. Other advances include the use of brackish water, and innovations such as using depleted reservoir sections to store water to increase the use of recycled water. It was noted that brackish water resources need to be mapped and understood in greater detail. The objective is to use brackish water at a cost equal to, or less, than fresh water

  2. 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.

  3. Gill histopathology of goldfish exposed to oil sands processed-waters

    International Nuclear Information System (INIS)

    Nero, V.; Farwell, A.J.; Dixon, D.G.; Lee, L.E.J.

    2002-01-01

    Large volumes of processed wastewater are generated through the oil extraction process at Alberta's Athabasca oil sand deposit. These wastewaters are very toxic to aquatic biota because they are high in salinity and consist of napthenic acids and polycyclic aromatic hydrocarbons (PAH). In this study, goldfish were caged in 3 different experimental ponds in order to evaluate the biological effects of aquatic reclamation alternatives for process-affected waters. The first pond was a control pond, while the other 2 ponds consisted of known and varying chemicals. The fish were exposed to the ponds for 19 days. Those in the pond with elevated levels of napthenic acids and high salinity exhibited severe gill histopathological changes. Alterations included epithelial hyperplasia resulting in severe lamellar fusion, chloride cell hyperplasia, and lamellar edema, all of which were believed to be defense responses of the fish. Additional severe gill alterations were also observed that may indicate the direct negative effects of oil sands processed-water on fish. Exposed goldfish also showed signs of necrosis and degenerative changes resulting in desquamation of the epithelial surfaces of the gill, which are symptoms seen in free-range exposure of yellow perch, a native fish species, at the same sites and exposure times

  4. Gill histopathology of goldfish exposed to oil sands processed-waters

    Energy Technology Data Exchange (ETDEWEB)

    Nero, V.; Farwell, A.J.; Dixon, D.G. [Waterloo Univ., ON (Canada). Dept. of Biology; Lister, A.; Van Der Kraak, G.J. [Guelph Univ., ON (Canada); Lee, L.E.J. [Wilfred Laurier Univ., Waterloo, ON (Canada). Dept. of Biology

    2002-07-01

    Large volumes of processed wastewater are generated through the oil extraction process at Alberta's Athabasca oil sand deposit. These wastewaters are very toxic to aquatic biota because they are high in salinity and consist of napthenic acids and polycyclic aromatic hydrocarbons (PAH). In this study, goldfish were caged in 3 different experimental ponds in order to evaluate the biological effects of aquatic reclamation alternatives for process-affected waters. The first pond was a control pond, while the other 2 ponds consisted of known and varying chemicals. The fish were exposed to the ponds for 19 days. Those in the pond with elevated levels of napthenic acids and high salinity exhibited severe gill histopathological changes. Alterations included epithelial hyperplasia resulting in severe lamellar fusion, chloride cell hyperplasia, and lamellar edema, all of which were believed to be defense responses of the fish. Additional severe gill alterations were also observed that may indicate the direct negative effects of oil sands processed-water on fish. Exposed goldfish also showed signs of necrosis and degenerative changes resulting in desquamation of the epithelial surfaces of the gill, which are symptoms seen in free-range exposure of yellow perch, a native fish species, at the same sites and exposure times.

  5. Origin and geochemistry of saline spring waters in the Athabasca oil sands region, Alberta, Canada

    International Nuclear Information System (INIS)

    Gue, Anita E.; Mayer, Bernhard; Grasby, Stephen E.

    2015-01-01

    Highlights: • Saline groundwater enters the Athabasca and Clearwater rivers in the AOSR via springs. • High TDS is due to subsurface dissolution of Devonian evaporites and carbonates. • Low δ 18 O values, and 3 H and 14 C data suggest some Laurentide glacial meltwater input. • Bacterial sulfate reduction, methanogenesis, and CH 4 oxidation were identified. • Metal and PAH contents are reported; bitumen does not appear to be major influence. - Abstract: The geochemistry of saline spring waters in the Athabasca oil sands region (AOSR) in Alberta (Canada) discharging from Devonian carbonate rocks into the Athabasca and Clearwater rivers was characterized for major ions, trace elements, dissolved gases, and polycyclic aromatic hydrocarbons (PAHs). In addition, stable isotope analyses of H 2 O, SO 4 , dissolved inorganic carbon (DIC), Sr, and CH 4 were used to trace the sources of spring waters and their dissolved solutes, and to identify subsurface processes affecting water chemistry. The spring waters had δ 18 O values as low as −23.5‰, suggesting they are composed of up to 75% Laurentide glacial meltwater. Tritium and radiocarbon age-dating results, analyzed for three spring waters, supported a glacial origin. The high salinity of the spring waters (TDS 7210–51,800 mg/L) was due to dissolution of Devonian evaporite and carbonate deposits in the subsurface. Spring waters were affected by bacterial (dissimilatory) sulfate reduction, methanogenesis, and methane oxidation. Trace elements were present in spring waters at varying concentrations, with only one spring containing several predominant oil sands metals (As, Fe, Mo, Ni, Se, Zn) suggesting bitumen as a source. Five springs contained elements (Al, As, B, Fe, Se) at concentrations exceeding water quality guidelines for the protection of aquatic life. Seven PAHs were detected in spring waters (total PAH concentrations ranged from 7.3 to 273.6 ng/L), but most springs contained a maximum of two PAHs

  6. Water repellency of clay, sand and organic soils in Finland

    Directory of Open Access Journals (Sweden)

    K. RASA

    2008-12-01

    Full Text Available Water repellency (WR delays soil wetting process, increases preferential flow and may give rise to surface runoff and consequent erosion. WR is commonly recognized in the soils of warm and temperate climates. To explore the occurrence of WR in soils in Finland, soil R index was studied on 12 sites of different soil types. The effects of soil management practice, vegetation age, soil moisture and drying temperature on WR were studied by a mini-infiltrometer with samples from depths of 0-5 and 5-10 cm. All studied sites exhibited WR (R index >1.95 at the time of sampling. WR increased as follows: sand (R = 1.8-5.0 < clay (R = 2.4-10.3 < organic (R = 7.9-undefined. At clay and sand, WR was generally higher at the soil surface and at the older sites (14 yr., where organic matter is accumulated. Below 41 vol. % water content these mineral soils were water repellent whereas organic soil exhibited WR even at saturation. These results show that soil WR also reduces water infiltration at the prevalent field moisture regime in the soils of boreal climate. The ageing of vegetation increases WR and on the other hand, cultivation reduces or hinders the development of WR.;

  7. Characteristics of streams and aquifers and processes affecting the salinity of water in the upper Colorado River basin, Texas

    Science.gov (United States)

    Slade, R.M.; Buszka, P.M.

    1994-01-01

    The upper Colorado River and some of its tributaries between Lake J.B. Thomas and O.H. Ivie Reservoir contain saline water (defined as water having dissolved-solids concentrations greater than 1,000 milligrams per liter). Dissolved-solids loads at nine streamflow water-quality stations increased from 1986 to 1988. The largest increases were in Beals Creek and in the Colorado River downstream from Beals Creek as a result of outflow of saline water from Natural Dam Salt Lake. The outflow contained 654,000 tons of dissolved solids and had a mean dissolved-solids concentration of 7,900 milligrams per liter. This amount represents about 51 percent of the dissolved-solids load to E.V. Spence Reservoir during 1986-88.

  8. Study on Modified Sand Filtration Towards Water Quality of Wet Market Waste Water

    Directory of Open Access Journals (Sweden)

    Saad F.N.M.

    2016-01-01

    Full Text Available Investigation on the potential of sand filter as a pre-treatment of waste water was done in Kangar wet market, Perlis. Besides, the best composition of filter in order to treat wastewater based on BOD, COD, SS, AN, turbidity and pH levels are further examined. In this study, there are four types of sand filter composition which the medias consist of fine sand and coarse sand while the modified sand filter are consist of sand, course sand and activated carbon prepared from rice husk and coconut shells. After 10 weeks of treatment, the results show that the concentration of BOD, COD, SS, AN, turbidity and pH were reduced up to 86%, 84%, 63%, 88%, 73%, respectively while pH nearly to neutral with 6.83. Moreover, the result also revealed that the sand filter added with rice husk almost complied with Standard B of Malaysia Environmental Quality (Sewage Regulations 2009 as well as gives the highest number of WQI with 36.81. Overall, WQI obtained in this study are ranged from 12.77 to 36.81.

  9. The effects of periphyton, fish and fertilizer dose on biological processes affecting water quality in earthen fish ponds.

    NARCIS (Netherlands)

    Milstein, A.; Azim, M.E.; Wahab, M.A.; Verdegem, M.C.J.

    2003-01-01

    The potential of periphyton-based aquaculture in South Asia is under investigation in an extensive research program. This paper is a further analysis of data from four experiments carried out in that framework, to explore periphyton, fish and fertilizer dose effects on water quality. Factor analysis

  10. Groundwater and surface-water interaction, water quality, and processes affecting loads of dissolved solids, selenium, and uranium in Fountain Creek near Pueblo, Colorado, 2012–2014

    Science.gov (United States)

    Arnold, L. Rick; Ortiz, Roderick F.; Brown, Christopher R.; Watts, Kenneth R.

    2016-11-28

    In 2012, the U.S. Geological Survey, in cooperation with the Arkansas River Basin Regional Resource Planning Group, initiated a study of groundwater and surface-water interaction, water quality, and loading of dissolved solids, selenium, and uranium to Fountain Creek near Pueblo, Colorado, to improve understanding of sources and processes affecting loading of these constituents to streams in the Arkansas River Basin. Fourteen monitoring wells were installed in a series of three transects across Fountain Creek near Pueblo, and temporary streamgages were established at each transect to facilitate data collection for the study. Groundwater and surface-water interaction was characterized by using hydrogeologic mapping, groundwater and stream-surface levels, groundwater and stream temperatures, vertical hydraulic-head gradients and ratios of oxygen and hydrogen isotopes in the hyporheic zone, and streamflow mass-balance measurements. Water quality was characterized by collecting periodic samples from groundwater, surface water, and the hyporheic zone for analysis of dissolved solids, selenium, uranium, and other selected constituents and by evaluating the oxidation-reduction condition for each groundwater sample under different hydrologic conditions throughout the study period. Groundwater loads to Fountain Creek and in-stream loads were computed for the study area, and processes affecting loads of dissolved solids, selenium, and uranium were evaluated on the basis of geology, geochemical conditions, land and water use, and evapoconcentration.During the study period, the groundwater-flow system generally contributed flow to Fountain Creek and its hyporheic zone (as a single system) except for the reach between the north and middle transects. However, the direction of flow between the stream, the hyporheic zone, and the near-stream aquifer was variable in response to streamflow and stage. During periods of low streamflow, Fountain Creek generally gained flow from

  11. Production of high quality water for oil sands application

    Energy Technology Data Exchange (ETDEWEB)

    Beaudette-Hodsman, C.; Macleod, B. [Pall Corp., Mississauga, ON (Canada); Venkatadri, R. [Pall Corp., East Hills, NY (United States)

    2008-10-15

    This paper described a pressurized microfiltration membrane system installed at an oil sands extraction site in Alberta. The system was designed to complement a reverse osmosis (RO) system installed at the site to produce the high quality feed water required by the system's boilers. Groundwater in the region exhibited moderate total suspended solids and high alkalinity and hardness levels, and the RO system required feed water with a silt density index of 3 or less. The conventional pretreatment system used at the site was slowing down production due to the severe fouling of the RO membranes. The new microfiltration system contained an automated PVDF hollow fiber microfiltration membrane system contained in a trailer. Suspended particles and bacteria were captured within the filter, and permeate was sent to the RO unit. Within 6 hours of being installed, the unit was producing water with SDI values in the range of 1.0 to 2.5. It was concluded that the microfiltration system performed reliably regardless of wide variations in feed water quality and flow rates. 3 refs., 1 tab., 8 figs.

  12. Processes of microbial pesticide degradation in rapid sand filters for treatment of drinking water

    DEFF Research Database (Denmark)

    Hedegaard, Mathilde Jørgensen; Albrechtsen, Hans-Jørgen

    Aerobic rapid sand filters for treatment of groundwater at waterworks were investigated for the ability to remove pesticides. The potential, kinetics and mechanisms of microbial pesticide removal was investigated in microcosms consisting of filter sand, treated water and pesticides in initial...... concentrations of 0.04-2.4 μg/L. The pesticides were removed from the water in microcosms with filter sand from all three investigated sand filters. Within the experimental periode of six to 13 days, 65-85% of the bentazone, 86-93% of the glyphosate, 97-99% of the p-nitrophenol was removed from the water phase...

  13. Experimental Investigation of Evaporation and Drainage in Wettable and Water-Repellent Sands

    Directory of Open Access Journals (Sweden)

    Dae Hyun Kim

    2015-05-01

    Full Text Available This study presents experimental results on evaporation and drainage in both wettable and water-repellent sands whose surface wettability was artificially modified by silanization. The 2D optical and 3D X-ray computed tomographic imaging was performed during evaporation and the water retention during cyclic drainage and infiltration was measured to assess effects of wettability and initial wetting conditions. The evaporation gradually induces its front at the early stage advance regardless of the wettability and sand types, while its rate becomes higher in water-repellent Ottawa sand than the wettable one. Jumunjin sand which has a smaller particle size and irregular particle shape than Ottawa sand exhibits a similar evaporation rate independent of wettability. Water-repellent sand can facilitate the evaporation when both wettable and water-repellent sands are naturally in contact with each other. The 3D X-ray imaging reveals that the hydraulically connected water films in wettable sands facilitate the propagation of the evaporation front into the soil such that the drying front deeply advances into the soil. For cyclic drainage-infiltration testing, the evolution of water retention is similar in both wettable and water-repellent sands when both are initially wet. However, when conditions are initially dry, water-repellent sands exhibit low residual saturation values. The experimental observations made from this study propose that the surface wettability may not be a sole factor while the degree of water-repellency, type of sands, and initial wetting condition are predominant when assessing evaporation and drainage behaviors.

  14. Ground penetrating radar water content mapping of golf course green sand layers

    Science.gov (United States)

    Information on the spatial distribution of water content across the sand layer component of a golf course green can be important to golf course superintendents for evaluating drainage effectiveness and scheduling irrigation. To estimate the bulk water content of the sand layer at point locations ac...

  15. Survival potential of Escherichia coli and Enterococci in subtropical beach sand: implications for water quality managers.

    Science.gov (United States)

    Hartz, A; Cuvelier, M; Nowosielski, K; Bonilla, T D; Green, M; Esiobu, N; McCorquodale, D S; Rogerson, A

    2008-01-01

    Fecal bacteria have traditionally been used as indicator organisms to monitor the quality of recreational waters. Recent work has questioned the robustness of traditional indicators, particularly at seawater bathing beaches. For example, a study of Florida beaches found unexpectedly high abundances of Escherichia coli, fecal coliforms, and enterococci in beach sand. The aim of the present study was to explain these abundances by assessing the survival of E. coli and enterococci in beach sand relative to seawater. We used a combination of quantitative laboratory mesocosm experiments and field observations. Results suggested that E. coli and enterococci exhibited increased survivability and growth in sand relative to seawater. Because fecal bacteria are capable of replicating in sand, at least under controlled laboratory conditions, the results suggest that sand may be an important reservoir of metabolically active fecal organisms. Experiments with "natural" mesocosms (i.e., unsterilized sand or water rich in micropredators and native bacteria) failed to show the same increases in fecal indicators as was found in sterile sand. It is postulated that this was due to predation and competition with indigenous bacteria in these "natural" systems. Nonetheless, high populations of indicators were maintained and recovered from sand over the duration of the experiment as opposed to the die-off noted in water. Indicator bacteria may wash out of sand into shoreline waters during weather and tidal events, thereby decreasing the effectiveness of these indicators as predictors of health risk and complicating the interpretations for water quality managers.

  16. Microbial degradation of pesticides in rapid sand filters for treatment of drinking water

    DEFF Research Database (Denmark)

    Hedegaard, Mathilde Jørgensen; Albrechtsen, Hans-Jørgen

    2014-01-01

    In Denmark drinking water supply is based on groundwater which is treated by aeration followed by filtration in rapid sand filters. Unfortunately pesticide contamination of the groundwater poses a threat to the water supply, since the simple treatment process at the waterworks is not considered...... to remove pesticides from the water phase and pesticides are detected in 24% of the active Danish waterworks wells. This study aimed at investigating the potential of microbial pesticide removal in rapid sand filters for drinking water treatment. Removal of the pesticides MCPP, bentazone, glyphosate...... and the degradation compound p-nitrophenol was investigated in the rapid sand filters at Islevbro and Sjælsø waterworks plant I and II. Microcosms were set up with sand from rapid sand filters, water and an initial pesticide concentration of 0.03-0.38 μg/L. In all the investigated waterworks the concentration...

  17. Watered down : overcoming federal inaction on the impact of oil sands development to water resources

    International Nuclear Information System (INIS)

    Droitsch, D.

    2009-11-01

    The oil sands industry is having a negative impact on Canada's fresh water resources and aquatic ecosystems. Members of the Government of the Northwest Territories (NT) and experts from scientific, non-governmental, and First Nations groups have stated at federal hearings that the federal government must involve itself in the protection of Canada's water resources. This report discussed compelling testimony from recent federal hearings by the House of Commons Standing Committee on Environment and Sustainable Development.The federal government must establish enforceable standards for key toxic substances created by oil sands activity. A water-sharing agreement must be established between Alberta, NT, Saskatchewan, and First Nations governments. Other recommendations included the establishment of a peer-reviewed assessment of the health impacts of industrial oil sands development on First Nations communities; the establishment of cumulative effects assessment procedures; the identification and protection of listed species at risk; and the establishment of proactive measures designed to ensure that oil sands operators pay for the environmental damage caused to water resources. 94 refs., 4 figs.

  18. Effect of water content on the water repellency for hydrophobized sands

    Science.gov (United States)

    Subedi, S.; Kawamoto, K.; Kuroda, T.; Moldrup, P.; Komatsu, T.

    2011-12-01

    Alternative earthen covers such as capillary barriers (CBs) and evapotranspirative covers are recognized as useful technical and low-cost solutions for limiting water infiltration and controlling seepage flow at solid waste landfills in semi-arid and arid regions. However, their application to the landfills at wet regions seems to be matter of concern due to loss of their impending capability under high precipitation. One of the possible techniques to enhance the impermeable properties of CBs is to alter soil grain surfaces to be water-repellent by mixing/coating hydrophobic agents (HAs). In order to examine a potential use of model sands hydrophobized with locally available and environmental-friendly HAs such as oleic acid (OA) and stearic acid (SA) for hydrophobic CBs. In the present study, we first characterized the effect of water content on the degree of water repellency (WR) for hydrophobized sands and volcanic ash soil at different depth. Secondly, the time dependency of the contact angle in hydrophobized sands and volcanic ash soils at different water content was evaluated. Further, the effects of hydrophobic organic matter contents on the WR of hydrophobized sands were investigated by horizontal infiltration test. We investigated the degree of WR as functions of volumetric water content (θ) of a volcanic ash soil samples from different depth and water adjusted hydrophobized sand samples with different ratio of HAs by using sessile drop method (SDM). The initial contact angle (αi) measured from SDM decreased gradually with increasing water content in OA and SA coated samples. Measured αi values for volcanic ash soils increased with increasing water content and reached a peak values of 111.7o at θ= 0.325 cm3 cm-3, where-after αi gradually decreased. Each test sample exhibited sharp decrease in contact angle with time at higher water content. Sorptivity values for oleic acid coated samples decreased with increasing HA content and reached the minimum

  19. Impact of polymeric membrane filtration of oil sands process water on organic compounds quantification.

    Science.gov (United States)

    Moustafa, Ahmed M A; Kim, Eun-Sik; Alpatova, Alla; Sun, Nian; Smith, Scott; Kang, Seoktae; Gamal El-Din, Mohamed

    2014-01-01

    The interaction between organic fractions in oil sands process-affected water (OSPW) and three polymeric membranes with varying hydrophilicity (nylon, polyvinylidene fluoride and polytetrafluoroethylene) at different pHs was studied to evaluate the impact of filtration on the quantification of acid-extractable fraction (AEF) and naphthenic acids (NAs). Four functional groups predominated in OSPW (amine, phosphoryl, carboxyl and hydroxyl) as indicated by the linear programming method. The nylon membranes were the most hydrophilic and exhibited the lowest AEF removal at pH of 8.7. However, the adsorption of AEF on the membranes increased as the pH of OSPW decreased due to hydrophobic interactions between the membrane surfaces and the protonated molecules. The use of ultra pressure liquid chromatography-high resolution mass spectrometry (UPLC/HRMS) showed insignificant adsorption of NAs on the tested membranes at pH 8.7. However, 26±2.4% adsorption of NAs was observed at pH 5.3 following the protonation of NAs species. For the nylon membrane, excessive carboxylic acids in the commercial NAs caused the formation of negatively charged assisted hydrogen bonds, resulting in increased adsorption at pH 8.2 (25%) as compared to OSPW (0%). The use of membranes for filtration of soluble compounds from complex oily wastewaters before quantification analysis of AEF and NAs should be examined prior to application.

  20. Parameters and mechanisms in the mechanical upgrading of Athabasca oil sands by a cold water process

    Energy Technology Data Exchange (ETDEWEB)

    Grant, G B

    1977-01-01

    The efficiency of sand rejection in the cold water mechanical upgrading of Athabasca oil sands has been studied in the operation of rotary contactors of 8.9 cm and 19.0 cm internal diameter, fitted with lifters. Duration of operation, rate of rotation, linear velocity of lifters, temperature, water to oil sands ratio, depth of charge to lifter height ratio, and internal diameter of the contactor have been identified as important parameters. Surfactant addition and presoaking of the feed had negligible effects on the process. A model has been proposed that accounts for the variation of extraction efficiency as a function of duration of operation, the data showing that both the equilibrium extraction efficiency and the rate constant were greater in the large contactor than the small contactor for equal rates of rotation, except when centrifuging occurred in the large contactor. Sand rejection was promoted by lifter-sand and contactor wall-sand impacts and by the action of shear fields within vortices created by the lifter. The impacts occurred for all loading conditions but the latter mechanism only contributed to the sand rejection process for depth-of-charge to lifter height ratios of one or greater. In addition, the contribution of shear fields was only significant for large water to oil sands ratios. Finally, the sand rejection process was affected significantly by variations in temperature. 37 refs., 34 figs., 11 tabs., 4 illus.

  1. Numerical simulation of water and sand blowouts when penetrating through shallow water flow formations in deep water drilling

    Science.gov (United States)

    Ren, Shaoran; Liu, Yanmin; Gong, Zhiwu; Yuan, Yujie; Yu, Lu; Wang, Yanyong; Xu, Yan; Deng, Junyu

    2018-02-01

    In this study, we applied a two-phase flow model to simulate water and sand blowout processes when penetrating shallow water flow (SWF) formations during deepwater drilling. We define `sand' as a pseudo-component with high density and viscosity, which can begin to flow with water when a critical pressure difference is attained. We calculated the water and sand blowout rates and analyzed the influencing factors from them, including overpressure of the SWF formation, as well as its zone size, porosity and permeability, and drilling speed (penetration rate). The obtained data can be used for the quantitative assessment of the potential severity of SWF hazards. The results indicate that overpressure of the SWF formation and its zone size have significant effects on SWF blowout. A 10% increase in the SWF formation overpressure can result in a more than 90% increase in the cumulative water blowout and a 150% increase in the sand blowout when a typical SWF sediment is drilled. Along with the conventional methods of well flow and pressure control, chemical plugging, and the application of multi-layer casing, water and sand blowouts can be effectively reduced by increasing the penetration rate. As such, increasing the penetration rate can be a useful measure for controlling SWF hazards during deepwater drilling.

  2. The role of water content in triboelectric charging of wind-blown sand.

    Science.gov (United States)

    Gu, Zhaolin; Wei, Wei; Su, Junwei; Yu, Chuck Wah

    2013-01-01

    Triboelectric charging is common in desert sandstorms and dust devils on Earth; however, it remains poorly understood. Here we show a charging mechanism of sands with the adsorbed water on micro-porous surface in wind-blown sand based on the fact that water content is universal but usually a minor component in most particle systems. The triboelectric charging could be resulted due to the different mobility of H(+)/OH(-) between the contacting sands with a temperature difference. Computational fluid dynamics (CFD) and discrete element method (DEM) were used to demonstrate the dynamics of the sand charging. The numerically simulated charge-to-mass ratios of sands and electric field strength established in wind tunnel agreed well with the experimental data. The charging mechanism could provide an explanation for the charging process of all identical granular systems with water content, including Martian dust devils, wind-blown snow, even powder electrification in industrial processes.

  3. Submerged Pond Sand Filter-A Novel Approach to Rural Water Supply

    DEFF Research Database (Denmark)

    Øhlenschlæger, Mia; Christensen, Sarah Christine Boesgaard; Bregnhøj, Henrik

    2016-01-01

    This study describes the new design and function of a modified version of a traditional slow sand filter. The Submerged Pond Sand Filter is built inside a pond and has a vertical as well as a horizontal flow of water through a sloped filter opening. The filter provides treated drinking water...... to a rural Indian village. The filter has functioned with minimal maintenance for five years without being subject to the typical scraping off and changing of sand as needed in traditional slow sand filters every few months. This five-year study showed bacterial removal efficiency of 97% on average...... to 10 CFU/100 mL on average compared to shorter pumping intervals (5 min). Though the treated water did not comply with the World Health Organization standards of 0 CFU/100 mL, the filter significantly improved water quality and provided one of the best sources of drinkable water in a water...

  4. Effect of hardening methods of moulding sands with water glass on structure of bonding bridges

    Directory of Open Access Journals (Sweden)

    M. Stachowicz

    2010-07-01

    Full Text Available Research on influence of hardening methods on structure of bonding bridges in moulding sands with sodium water glass is presented.Moulding sands with addition of 2.5 % of binder with molar module 2.0 were hardened with CO2 and dried in traditional way or hardenedwith microwaves. It was proved that the hardening method affects structure of bonding bridges, correlating with properties of the hardened moulding sands. It was found that strength of the moulding sands hardened with microwaves for 4 min is very close to that measured after traditional drying at 110 °C for 120 min. So, application of microwave hardening ensures significant shortening of the process time to the value comparable with CO2 hardening but guaranteeing over 10-fold increase of mechanical properties. Analysis of SEM images of hardened moulding sands permitted explaining differences in quality parameters of moulding sands by connecting them with structure of the created bonding bridges.

  5. Sand and gravel mining: effects on ground water resources in Hancock county, Maine, USA

    Science.gov (United States)

    Peckenham, John M.; Thornton, Teresa; Whalen, Bill

    2009-01-01

    Based on this preliminary study, existing sand and gravel mining regulations (in Maine, USA) can be inferred to provide some protection to water resources. Sand and gravel deposits are important natural resources that have dual uses: mining for construction material and pumping for drinking water. How the mining of sand and gravel affects aquifers and change aquifer vulnerability to contamination is not well documented. Mining regulations vary greatly by state and local jurisdiction. This study test metrics to measure the effectiveness of mining regulations. The sand and gravel aquifer system studied is covered with former and active gravel pits to nearly 25% of its areal extent. Data from homeowner interviews and field measurements found scant evidence of changes in water quantity. Water quality analyses collected from springs, streams, ponds and wells indicate that the aquifer was vulnerable to contamination by chloride and nitrate. However, water quality changes can not be related directly to mining activities.

  6. Stratification of nitrification activity in rapid sand filters for drinking water treatment

    DEFF Research Database (Denmark)

    Tatari, Karolina; Smets, Barth F.; Musovic, Sanin

    2013-01-01

    Rapid sand filters used in groundwater treatment remove ammonium, iron and manganese from the water. Ammonium is removed biologically by nitrifying microorganisms attached on the sand surface. Nitrification kinetics and activity is strongly affected by filter design and operation, which are the key...... and maximum nitrification capacity are derived and used to quantify nitrification activity. Nitrification activity was concentrated at the top 10 cm of filter depth, and maximum nitrification capacity was 7 g NH4+-N/ m3 sand/h compared with 0.8-0.4 g NH4+-N/ m3 sand/h in the middle and bottom layers. A water...... of this study is to investigate nitrification activity in a rapid sand filter, with focus on its homogeneity and how it relates to filter performance. Two groundwater treatment plants in Denmark were selected for the experimental investigations. Plant 1 operates a single line of pre and after filters and has...

  7. In vitro evaluation of the toxic effects and endocrine disrupting potential of oil sands processed water and naphthenic acids

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, X.; Wiseman, S.; Higley, E.; Jones, P.D.; Hecker, M.; Giesy, J.P. [Saskatchewan Univ., Saskatoon, SK (Canada); Gamel El Din, M.; Martin, J.W. [Alberta Univ., Edmonton, AB (Canada)

    2009-07-01

    Naphthenic acids (NAs) are the primary toxic constituents of oil sands process-affected waters (OSPW). This presentation reported on a series of in vitro studies that were initiated to evaluate potential endocrine modulating effects of OSPW and their constituent NAs. The H295R steroidogenesis bioassay was used to examine the impact of OSPW and NA on 52 steroidogenesis. In particular, dose-response and time course studies were conducted to evaluate the impact of OSPW and NAs on testosterone and estradiol production. Aromatase activity and transcript abundance of the key 11 steroidogenic enzymes were also quantified to complement analysis of hormone levels. The MVLN trans-activation assay was used to test the estrogenicity/anti-estrogenicity of OSPW and NAs. In vitro cell viability and apoptosis (live-dead) caused by OSPW and NAs was quantified by the MTS reduction and caspase-3/7 activity in H295R and MVLN cells.

  8. Band gaps and localization of surface water waves over large-scale sand waves with random fluctuations

    Science.gov (United States)

    Zhang, Yu; Li, Yan; Shao, Hao; Zhong, Yaozhao; Zhang, Sai; Zhao, Zongxi

    2012-06-01

    Band structure and wave localization are investigated for sea surface water waves over large-scale sand wave topography. Sand wave height, sand wave width, water depth, and water width between adjacent sand waves have significant impact on band gaps. Random fluctuations of sand wave height, sand wave width, and water depth induce water wave localization. However, random water width produces a perfect transmission tunnel of water waves at a certain frequency so that localization does not occur no matter how large a disorder level is applied. Together with theoretical results, the field experimental observations in the Taiwan Bank suggest band gap and wave localization as the physical mechanism of sea surface water wave propagating over natural large-scale sand waves.

  9. Deflouridation of water using physico-chemically treated sand as a ...

    African Journals Online (AJOL)

    Prof. Dr. Mahamadi

    chemically modified sand has potential application as an adsorbent for fluoride ions removal. ... activated carbon, minerals, fish bone charcoal, coconut ... (2003), established that red soils ..... solutions by granular ferric hydroxide (GFH). Water ...

  10. Intertidal beach sands as monitors for heavy metal pollution in coastal water bodies

    International Nuclear Information System (INIS)

    Lacerda, L.D. de; Pfeiffer, W.C.; Fiszman, M.

    Intertidal beach sands were investigated for their use as indicators of metal transport in a contaminated water body, Sepetiba Bay, Rio de Janeiro, Brazil, and are proposed as an alternative and rapid screening method to determine metal pollution status of coastal areas. The results showed that, at least for Cu, Cr, Zn and Pb, beach sands can be included in the existing environmental monitoring programs for heavy metal pollution in water bodies. (Author) [pt

  11. Microbial pesticide removal in rapid sand filters for drinking water treatment – Potential and kinetics

    DEFF Research Database (Denmark)

    Hedegaard, Mathilde Jørgensen; Albrechtsen, Hans-Jørgen

    2014-01-01

    Filter sand samples, taken from aerobic rapid sand filters used for treating groundwater at three Danish waterworks, were investigated for their pesticide removal potential and to assess the kinetics of the removal process. Microcosms were set up with filter sand, treated water, and the pesticides...... or metabolites mecoprop (MCPP), bentazone, glyphosate and p-nitrophenol were applied in initial concentrations of 0.03–2.4 μg/L. In all the investigated waterworks the concentration of pesticides in the water decreased – MCPP decreased to 42–85%, bentazone to 15–35%, glyphosate to 7–14% and p-nitrophenol 1....../L) increased from 0.21%/g filter sand to 0.75%/g filter sand, when oxygen availability was increased from 0.28 mg O2/g filter sand to 1.09 mg O2/g filter sand. Bentazone was initially cleaved in the removal process. A metabolite, which contained the carbonyl group, was removed rapidly from the water phase...

  12. 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

  13. The influence of microwave heating and water glass kind on the properties of molding sands

    Directory of Open Access Journals (Sweden)

    K. Granat

    2008-03-01

    Full Text Available This work presents rcsults of research on thc influcncc of microwave heating time on the process of hardening of warcr glass moldingsands. Essential influence of this drying process on basic properties such as: cornprcssion, bcnding mind tcnsitc strcng~h as well aspcrrneabili~y and war resistance, has bccn found. It has bccn proved, that at1 thc investigated sorts of sodium water glass could be uscd asbinding material of molding sands intended for curing with the microwave process healing. It has bccn found, while analyzing the rcsultsof property studics or microwavc heated molding sands with 2.5% addition of water glass, that aIl available on the markct kinds of thisbinding agent (inctuding the most frequently uscd in foundry 145 and 149 kinds after microwave heating guarantee very goodcompression, bending and tensile strength as well as permeability and wcar resistance. Moroovcr, it has bccn dctcrmined that the optimalcuring powcr of molding sands containing various kinds of water gIass is 560 W. AII values exceeding this rcsult in stabilization of basicpropcrtics of molding sands. The use of microwave curing of water glass molding sands results in a significant decrease of hardeningprocess time. full stabilization of molding sands as well as much lower energy consumption.

  14. Contribution of sand-associated enterococci to dry weather water quality.

    Science.gov (United States)

    Halliday, Elizabeth; Ralston, David K; Gast, Rebecca J

    2015-01-06

    Culturable enterococci and a suite of environmental variables were collected during a predominantly dry summer at a beach impacted by nonpoint source pollution. These data were used to evaluate sands as a source of enterococci to nearshore waters, and to assess the relationship between environmental factors and dry-weather enterococci abundance. Best-fit multiple linear regressions used environmental variables to explain more than half of the observed variation in enterococci in water and dry sands. Notably, during dry weather the abundance of enterococci in dry sands at the mean high-tide line was significantly positively related to sand moisture content (ranging from sands. Tidal forcing modulated the abundance of enterococci in the water, as both turbidity and enterococci were elevated during ebb and flood tides. The probability of samples violating the single-sample maximum was significantly greater when collected during periods with increased tidal range: spring ebb and flood tides. Tidal forcing also affected groundwater mixing zones, mobilizing enterococci from sand to water. These data show that routine monitoring programs using discrete enterococci measurements may be biased by tides and other environmental factors, providing a flawed basis for beach closure decisions.

  15. Potential of the application of the modified polysaccharides water solutions as binders of moulding sands

    Directory of Open Access Journals (Sweden)

    K. Kaczmarska

    2015-10-01

    Full Text Available The results of preliminary tests of selected properties of the moulding sands with the binder in the form of a 5 % water solution of the sodium salt of carboxymethyl starch (with a degree of substitution (DS of 0,2 and 0,87 arepresented in this study. The moulding sand properties such as permeability, abrasion resistance, tensile and bendingstrength - after curing - are shown in series of tests. The cure process was conducted in a field of electromagnetic radiation within the microwave range. The effect of the microwave treatment on the moulding sand was evaporating of water (solvent in a binder and cross-linking of the polymeric binder. As a result the cured moulding sands with particular properties, essential in the context of its application in the mould technology in the foundry industry, were obtained.

  16. Biodegradation of gasoline compounds (BTEX) in a water works sand filter

    DEFF Research Database (Denmark)

    Arvin, Erik; Engelsen, P.; Sebber, U.

    2004-01-01

    Various chemical compounds including aromatic gasoline compounds frequently contaminate drinking water wells in urban areas. Because ground water treatment is simple, usually consisting of aeration/stripping and sand-filtration, it is of significant interest to know the ability of the conventional...... treatment to remove the chemical contaminants. The removal of gasoline compounds was investigated in a two-stage pilot scale sand filter, each with a filter depth of 0.8-1 m and with a filtration rate of 7.6 m/h. The concentrations of aromatic compounds were in the range 7-15 mu g/L, which are realistically...... sand grains). Influent iron concentrations in the range 0-4 mg/L and backwashing did not adversely affect the biodegradation of hydrocarbons. This study has shown that a conventional biological active sand filter can act as an efficient barrier against gasoline compounds, thereby saving the consumer...

  17. High-temperature expansion and knock-out properties of moulding sands with water glass

    Directory of Open Access Journals (Sweden)

    Major-Gabryś K.

    2007-01-01

    Full Text Available The article focuses on the topic of improving the knock-out properties of moulding sand with water glass and ester hardener. It is settled that the cause of worse knock-out properties of moulding sand can be brought by their thermal expansion in increased temperatures. There is a presentation of the influence of different additives, containing Al2O3, on moulding sands’ expansion in increased temperatures. Within the frames of research, there was an elaboration of the influence of authors own additive- Glassex, on the expansion phenomenon of moulding sands with water glass and ester hardener. It is concluded, that the new additive stops the expansion of moulding sands and as well it improves their knock-out properties.

  18. Microbial degradation of pesticides in rapid sand filters used for drinking water treatment

    DEFF Research Database (Denmark)

    Hedegaard, Mathilde Jørgensen

    significantly with the maximum methane concentration in the raw water and did not correlate with other water quality parameters, such as the ammonium concentration. Furthermore, the connection between bentazone degradation and methane oxidation in filter sand was demonstrated by inhibition experiments, in which...... sustainable methods to remove pesticides from polluted water sources. Aeration of anaerobic groundwater, followed by biological rapid sand filtration is a widespread technology in drinking water treatment. Even though these systems are not designed for removal of trace contaminants, they have shown potential...... for microbial degradation of pesticides and their degradation products. If pesticides can be removed in rapid sand filters, it is of large commercial interest due to the importance in maintaining a simple, sustainable water treatment. To take advantage of the microbial pesticide degradation and identify...

  19. Moisture diffusion coefficients determination of furan bonded sands and water based foundry coatings

    DEFF Research Database (Denmark)

    Di Muoio, Giovanni Luca; Tiedje, Niels Skat

    2016-01-01

    Moisture content in furan bonded sand and water based coatings can be one of the main causes for gas related defects in large cast iron parts. Moisture diffusion coefficients for these materials are needed to precisely predict the possible moisture levels in foundry moulds. In this study, we first...... provide an example on how it is possible to apply this knowledge to estimate moisture variation in a sand mould during production....

  20. 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.

  1. Evaluating regional water scarcity: Irrigated crop water budgets for groundwater management in the Wisconsin Central Sands

    Science.gov (United States)

    Nocco, M. A.; Kucharik, C. J.; Kraft, G.

    2013-12-01

    Regional water scarcity dilemmas between agricultural and aquatic land users pervade the humid northern lake states of Wisconsin, Minnesota, and Michigan, where agricultural irrigation relies on groundwater drawn from shallow aquifers. As these aquifers have strong connectivity to surface waters, irrigation lowers water levels in lakes and wetlands and reduces stream discharges. Irrigation expansion has cultivated a 60-year water scarcity dilemma in The Wisconsin Central Sands, the largest irrigated region in the humid northern lake states, dedicated to potato, maize, and processing vegetable production. Irrigation has depleted Wisconsin Central Sands surface waters, lowering levels in some lakes by over 2 m and drying some coldwater trout streams. Aquatic ecosystems, property values, and recreational uses in some surface waters have been devastated. While the causal link between pumping and surface water stress is established, understanding crop-mediated processes, such as the timing and magnitude of groundwater consumption by evapotranspiration (ET) and groundwater recharge, will be useful in management of groundwater, irrigated cropping systems, and surface water health. Previous modeling and field efforts have compared irrigated crop water use to a natural reference condition on a net annual basis. As a result, we presently understand that for irrigated potatoes and maize, the average annual ET is greater and therefore, the average annual recharge is less than rainfed row crops, grasslands, and both coniferous and deciduous forests. However, we have a limited understanding of the magnitude and timing of ET and recharge from irrigated cropping systems on shorter time scales that proceed with the annual cropping cycle (i.e. planting, full canopy, harvest, residue cover). We seek to understand the spatiotemporal variability of crop water budgets and associated water scarcity in the Wisconsin Central Sands through detailed measurements of drainage (potential

  2. Submerged Pond Sand Filter—A Novel Approach to Rural Water Supply

    Directory of Open Access Journals (Sweden)

    Mia Øhlenschlæger

    2016-06-01

    Full Text Available This study describes the new design and function of a modified version of a traditional slow sand filter. The Submerged Pond Sand Filter is built inside a pond and has a vertical as well as a horizontal flow of water through a sloped filter opening. The filter provides treated drinking water to a rural Indian village. The filter has functioned with minimal maintenance for five years without being subject to the typical scraping off and changing of sand as needed in traditional slow sand filters every few months. This five-year study showed bacterial removal efficiency of 97% on average with a level of faecal coliforms of 2 ± 2 colony forming units (CFU/100 mL measured in the treated water. Turbidity was visibly removed during treatment. When water was retrieved from the filter through a manual pump for long consistent time intervals (60 min, faecal coliform counts increased from four to 10 CFU/100 mL on average compared to shorter pumping intervals (5 min. Though the treated water did not comply with the World Health Organization standards of 0 CFU/100 mL, the filter significantly improved water quality and provided one of the best sources of drinkable water in a water-depleted area, where only surface water was available. Furthermore, it is a sustainable treatment method due to low maintenance requirements.

  3. Evaluation of methods to sample fecal indicator bacteria in foreshore sand and pore water at freshwater beaches.

    Science.gov (United States)

    Vogel, Laura J; Edge, Thomas A; O'Carroll, Denis M; Solo-Gabriele, Helena M; Kushnir, Caitlin S E; Robinson, Clare E

    2017-09-15

    Fecal indicator bacteria (FIB) are known to accumulate in foreshore beach sand and pore water (referred to as foreshore reservoir) where they act as a non-point source for contaminating adjacent surface waters. While guidelines exist for sampling surface waters at recreational beaches, there is no widely-accepted method to collect sand/sediment or pore water samples for FIB enumeration. The effect of different sampling strategies in quantifying the abundance of FIB in the foreshore reservoir is unclear. Sampling was conducted at six freshwater beaches with different sand types to evaluate sampling methods for characterizing the abundance of E. coli in the foreshore reservoir as well as the partitioning of E. coli between different components in the foreshore reservoir (pore water, saturated sand, unsaturated sand). Methods were evaluated for collection of pore water (drive point, shovel, and careful excavation), unsaturated sand (top 1 cm, top 5 cm), and saturated sand (sediment core, shovel, and careful excavation). Ankle-depth surface water samples were also collected for comparison. Pore water sampled with a shovel resulted in the highest observed E. coli concentrations (only statistically significant at fine sand beaches) and lowest variability compared to other sampling methods. Collection of the top 1 cm of unsaturated sand resulted in higher and more variable concentrations than the top 5 cm of sand. There were no statistical differences in E. coli concentrations when using different methods to sample the saturated sand. Overall, the unsaturated sand had the highest amount of E. coli when compared to saturated sand and pore water (considered on a bulk volumetric basis). The findings presented will help determine the appropriate sampling strategy for characterizing FIB abundance in the foreshore reservoir as a means of predicting its potential impact on nearshore surface water quality and public health risk. Copyright © 2017 Elsevier Ltd. All rights

  4. Water Use for Cultivation Management of Watermelon in Upland Field on Sand Dune

    Science.gov (United States)

    Hashimoto, Iwao; Senge, Masateru; Itou, Kengo; Maruyama, Toshisuke

    Early-maturing cultivation of watermelon in a plastic tunnel was invetigated in upland field on sand dune on the coast of the Japan Sea to find water use to control blowing sand and to transplant seedlings. This region has low precipitation, low humidity, and strong wind in March and April, when sand is readily blown in the field. Water is used to control blowing sand on days with precipitation below 5 mm, minimum humidity below the meteorological average in April, and maximum wind velocity above the meteorological average in April. For the rooting and growth of watermelon seedlings, soil temperature needs to be raised because it is low in April. Ridges are mulched with transparent, porous polyethylene films 10 or more days before transplanting the seedlings and irrigated with sprinklers on fine days for the thermal storage of solar energy. The stored heat steams the mulched ridges to raise soil temperature to 15°C or higher on the day of transplanting the seedlings. The total amount of irrigation water used for watermelon cultivation was 432.7 mm, of which 23.6 mm was for blowing sand control and 26.6 mm was for transplanting the seedlings. The combined amount, 50.2 mm, is 11.6% of the total amount of water used for cultivation management.

  5. Process water treatment in Canada's oil sands industry : 2 : a review of emerging technologies

    International Nuclear Information System (INIS)

    Allen, E.W.

    2008-01-01

    This review was conducted to identify candidate treatment technologies for treating oil sands process water. The oil sands industry in Canada uses large volumes of fresh water in order to extract bitumen deposits. The development of process water treatment technologies has become a critical issue for the industry, particularly as oil sand production is expected to triple in the next decade. However, treatment technologies must be adapted to consider the fouling potential of bitumens and fine clays as well as the effect of alkaline process water on treatment performance. The review included developments in chemical modifications to membranes and adsorbents designed to improve pollutant removal and reduce fouling; hybridization technologies designed to enhance the biological treatment of toxic feedwaters; recent advances in photocatalytic oxidation technologies for organic compounds; and new designs for large-scale treatment wetlands for polluted waste waters. It was concluded that major knowledge gaps must be optimized and preliminary studies must be conducted in order to understand how the treatment technologies will be affected by the chemical and physical characteristics of oil sands process water. 188 refs., 8 tabs

  6. Perceptual Processing Affects Conceptual Processing

    Science.gov (United States)

    van Dantzig, Saskia; Pecher, Diane; Zeelenberg, Rene; Barsalou, Lawrence W.

    2008-01-01

    According to the Perceptual Symbols Theory of cognition (Barsalou, 1999), modality-specific simulations underlie the representation of concepts. A strong prediction of this view is that perceptual processing affects conceptual processing. In this study, participants performed a perceptual detection task and a conceptual property-verification task…

  7. [Effect of shifting sand burial on evaporation reduction and salt restraint under saline water irrigation in extremely arid region].

    Science.gov (United States)

    Zhang, Jian-Guo; Zhao, Ying; Xu, Xin-Wen; Lei, Jia-Qiang; Li, Sheng-Yu; Wang, Yong-Dong

    2014-05-01

    The Taklimakan Desert Highway Shelterbelt is drip-irrigated with high saline groundwater (2.58-29.70 g x L(-1)), and shifting sand burial and water-salt stress are most common and serious problems in this region. So it is of great importance to study the effect of shifting sand burial on soil moisture evaporation, salt accumulation and their distribution for water saving, salinity restraint, and suitable utilization of local land and water resources. In this study, Micro-Lysimeters (MLS) were used to investigate dynamics of soil moisture and salt under different thicknesses of sand burial (1, 2, 3, 4, and 5 cm), and field control experiments of drip-irrigation were also carried out to investigate soil moisture and salt distribution under different thicknesses of shifting sand burial (5, 10, 15, 20, 25, 30, 35, and 40 cm). The soil daily and cumulative evaporation decreased with the increase of sand burial thickness in MLS, cumulative evaporation decreased by 2.5%-13.7% compared with control. And evaporative inhibiting efficiency increased with sand burial thickness, evaporative inhibiting efficiency of 1-5 cm sand burial was 16.7%-79.0%. Final soil moisture content beneath the interface of sand burial increased with sand burial thickness, and it increased by 2.5%-13.7% than control. The topsoil EC of shifting sand in MLS decreased by 1.19-6.00 mS x cm(-1) with the increasing sand burial thickness, whereas soil salt content beneath the interface in MLS increased and amplitude of the topsoil salt content was higher than that of the subsoil. Under drip-irrigation with saline groundwater, average soil moisture beneath the interface of shifting sand burial increased by 0.4% -2.0% compare with control, and the highest value of EC was 7.77 mS x cm(-1) when the sand burial thickness was 10 cm. The trend of salt accumulation content at shifting sand surface increased firstly, and then decreased with the increasing sand burial thickness. Soil salt contents beneath the

  8. 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.

  9. Transport of nanoparticles with dispersant through biofilm coated drinking water sand filters.

    Science.gov (United States)

    Li, Zhen; Aly Hassan, Ashraf; Sahle-Demessie, Endalkachew; Sorial, George A

    2013-11-01

    This article characterizes, experimentally and theoretically, the transport and retention of engineered nanoparticles (NP) through sand filters at drinking water treatment plants (DWTPs) under realistic conditions. The transport of four commonly used NPs (ZnO, CeO2, TiO2, and Ag, with bare surfaces and coating agents) through filter beds filled with sands from either acid washed and calcined, freshly acquired filter media, and used filter media from active filter media, were investigated. The study was conducted using water obtained upstream of the sand filter at DWTP. The results have shown that capping agents have a determinant importance in the colloidal stability and transport of NPs through the different filter media. The presence of the biofilm in used filter media increased adsorption of NPs but its effects in retaining capped NPs was less significant. The data was used to build a mathematical model based on the advection-dispersion equation. The model was used to simulate the performance of a scale-up sand filter and the effects on filtration cycle of traditional sand filtration system used in DWTPs. Published by Elsevier Ltd.

  10. The influence of pore-water advection, benthic photosynthesis, and respiration on calcium carbonate dynamics in reef sands

    NARCIS (Netherlands)

    Rao, A.M.F.; Polerecky, L.; Ionescu, D.; Meysman, F.J.R.; de-Beer, D.

    2012-01-01

    To investigate diel calcium carbonate (CaCO3) dynamics in permeable coral reef sands, we measured pore-water profiles and fluxes of oxygen (O2), nutrients, pH, calcium (Ca2+), and alkalinity (TA) across the sediment-water interface in sands of different permeability

  11. Application of acoustical methods to the measurement of water content in sand

    International Nuclear Information System (INIS)

    Nazarov, V.E.; Radostin, A.V.; Stepanyants, Y.A.

    2000-10-01

    Results of laboratory experiments on the propagation of high-frequency acoustic waves (f = 100 kHz) in a glass tube, filled with river sand are presented. Several sand samples have been used with different water content: dry, unsaturated and completely water saturated. It is shown that the dissipative coefficient of acoustic waves decreases with increasing wave amplitude. This 'self-brightening' phenomenon takes place over the whole range of moisture content, from zero to 100%, but its degree of manifestation depends on the moisture content. The exponent of the dissipative nonlinearity α, is found to be the most sensitive parameter to the moisture content and is determined on the basis of measurements. It is considered to be a good indicator of water content in porous media and provides an opportunity to measure water content in such materials indirectly by means of an acoustic method. A simple phenomenological model is presented to explain the experimental results

  12. Effects of dynamic operating conditions on nitrification in biological rapid sand filters for drinking water treatment

    DEFF Research Database (Denmark)

    Lee, Carson Odell; Boe-Hansen, Rasmus; Musovic, Sanin

    2014-01-01

    Biological rapid sand filters are often used to remove ammonium from groundwater for drinking water supply. They often operate under dynamic substrate and hydraulic loading conditions, which can lead to increased levels of ammonium and nitrite in the effluent. To determine the maximum nitrification...... operating conditions. The ammonium removal rate of the filter was determined by the ammonium loading rate, but was independent of both the flow and influent ammonium concentration individually. Ammonia-oxidizing bacteria and archaea were almost equally abundant in the filter. Both ammonium removal...... rates and safe operating windows of rapid sand filters, a pilot scale rapid sand filter was used to test short-term increased ammonium loads, set by varying either influent ammonium concentrations or hydraulic loading rates. Ammonium and iron (flock) removal were consistent between the pilot...

  13. Performance comparison of sand and fine sawdust vermifilters in treating concentrated grey water for urban poor.

    Science.gov (United States)

    Adugna, Amare T; Andrianisa, Harinaivo A; Konate, Yacouba; Ndiaye, Awa; Maiga, Amadou H

    2015-01-01

    A comparative investigation was conducted for 10 months with sand and fine sawdust vermifilters and a control unit to treat concentrated grey water generated from a poor urban household in Ouagadougou, Burkina Faso. Each of the filters was made up of cylindrical DN200-PVC pipes and filled with 10 cm of gravel at the bottom. On top of the gravel layer, filter 1 (fully sand, F1) was completed with 40 cm of sand and 10 cm of fine sawdust, filter 2 (partially sand, F2) with 20 cm of sand and 30 cm of fine sawdust, respectively, and filter 3 (fully sawdust, F3) and 4 (control, F4) with 50 cm of fine sawdust only. Two hundred Eudrilus eugeniae earthworms were inoculated in each of the vermifilters. The vermifiltration system was supplied with grey water four times per day at a hydraulic loading rate of 64 L/m(2)/day on a batch basis. The removal efficiencies of biological oxygen demand, total chemical oxygen demand, and dissolved chemical oxygen demand (dCOD) by the vermifilters were 25-30% higher than the control, but little differences were observed in terms of total suspended solids and coliform removal efficiencies. Though there was no significant difference in the performance of the three vermifilters (p > 0.05), except for dCOD removal efficiency, the lifespan of F2 and F3 was longer than that of F1. Therefore, fine sawdust can substitute sand as a filter medium in vermifilters.

  14. Microbiological quality assessment of sand and water from three selected beaches of South Coast, São Paulo State, Brazil.

    Science.gov (United States)

    Pinto, K C; Hachich, E M; Sato, M I Z; Di Bari, M; Coelho, M C L S; Matté, M H; Lamparelli, C C; Razzolini, M T P

    2012-01-01

    This study aimed to assess the sanitary quality of water, and wet and dry sand from three beaches located in the South Coast region of São Paulo State, Brazil, selected taking into account the frequency of tourists and the water quality (good, fair and poor). Thirty-six water samples each of wet and dry sand and seawater were collected monthly over a period of one year and analyzed for fecal indicator bacteria (FIB: thermotolerant coliforms, Escherichia coli, and enterococci), presumptive Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans and dermatophytes. The results revealed FIB concentrations more elevated in dry sand followed by wet sand and water. P. aeruginosa and presumptive S. aureus were detected with a similar frequency in water and sand samples, but maximum concentrations and geometric means were higher in dry sand. C. albicans was detected only in water samples whereas the dermatophyte Microsporum sp. was isolated exclusively from dry and wet sand samples. This evaluation showed also that the environment had a significant influence on P. aeruginosa but not on presumptive S. aureus concentrations. According to threshold values proposed in the literature for E. coli and enterococci dry sand densities, none of the beaches would be considered of sufficient quality for recreational activities.

  15. Water productivity analysis of sand dams irrigation farming in northern Ethiopia

    Directory of Open Access Journals (Sweden)

    Lorenzo Villani

    2018-06-01

    Full Text Available Water scarcity in drylands is the main problem that has to be tackled by farmers and practitioners that work in these areas. Climate change and increased and wealthier population are expected to put additional stress on the water resource. A large number of studies is calling to focus efforts to enhance water productivity (WP, and one of the most promising option is represented by water harvesting, the collection and storage of runoff water to be used for beneficially uses. Among the available technologies, sand dams are experiencing a renovated interest because of their relative simplicity and their potential. This research aims to deepen the knowledge about WP of water harvesting systems studying a sand dam irrigation system in Tigray, north Ethiopia, where farmers are getting used to this new technology. The research was carried out in the period March-April 2017, when farmers use sand dams water to irrigate off-season maize. We analysed a representative plot irrigated through a shallow well drilled in the sand dam aquifer, in terms of yield, Crop Water Productivity (CWP, Crop Water Productivity based on Evapotranspiration (CWP(ET and Economic Water Productivity (EWP, through field data analysis and a validated Aquacrop model. CWP(ET was found to be low (1.12 kg of grain per m3 of evapotranspired water, due by both inefficient water application and low soil fertility. Aquacrop model results showed that changing the irrigation schedule can increase CWP(ET up to 1.35 kg/m3 and EWP up to 3.94 birr/m3, but yield gap is mainly due to the low soil fertility. Interventions on soil fertility can raise yields from the original 3.3 up to 8.5 kg/ha, and thus CWP(ET and EWP up to 2.94 kg/m3 and 9.54 birr/m3 respectively. To enhance the effect of sand dams in northern Ethiopia, a set of measures, including conservation agriculture, is then proposed.

  16. Copper deficiency can limit nitrification in biological rapid sand filters for drinking water production

    DEFF Research Database (Denmark)

    Wagner, Florian Benedikt; Nielsen, Peter Borch; Boe-Hansen, Rasmus

    2016-01-01

    Incomplete nitrification in biological filters during drinking water treatment is problematic, as it compromises drinking water quality. Nitrification problems can be caused by a lack of nutrients for the nitrifying microorganisms. Since copper is an important element in one of the essential...... enzymes in nitrification, we investigated the effect of copper dosing on nitrification in different biological rapid sand filters treating groundwater. A lab-scale column assay with filter material from a water works demonstrated that addition of a trace metal mixture, including copper, increased ammonium...... to the bulk phase. Overall, copper dosing to poorly performing biological rapid sand filters increased ammonium removal rates significantly, achieving effluent concentrations of below 0.01 mg NH4-N L-1, and had a long-term effect on nitrification performance....

  17. Policy Analysis of Water Availability and Use Issues for Domestic Oil Shale and Oil Sands Development

    Energy Technology Data Exchange (ETDEWEB)

    Ruple, John [Univ. of Utah, Salt Lake City, UT (United States); Keiter, Robert [Univ. of Utah, Salt Lake City, UT (United States)

    2010-03-01

    Oil shale and oil sands resources located within the intermountain west represent a vast, and as of yet, commercially untapped source of energy. Development will require water, and demand for scarce water resources stands at the front of a long list of barriers to commercialization. Water requirements and the consequences of commercial development will depend on the number, size, and location of facilities, as well as the technologies employed to develop these unconventional fuels. While the details remain unclear, the implication is not – unconventional fuel development will increase demand for water in an arid region where demand for water often exceeds supply. Water demands in excess of supplies have long been the norm in the west, and for more than a century water has been apportioned on a first-come, first-served basis. Unconventional fuel developers who have not already secured water rights stand at the back of a long line and will need to obtain water from willing water purveyors. However, uncertainty regarding the nature and extent of some senior water claims combine with indeterminate interstate river management to cast a cloud over water resource allocation and management. Quantitative and qualitative water requirements associated with Endangered Species protection also stand as barriers to significant water development, and complex water quality regulations will apply to unconventional fuel development. Legal and political decisions can give shape to an indeterminate landscape. Settlement of Northern Ute reserved rights claims would help clarify the worth of existing water rights and viability of alternative sources of supply. Interstate apportionment of the White River would go a long way towards resolving water availability in downstream Utah. And energy policy clarification will help determine the role oil shale and oil sands will play in our nation’s future.

  18. Replicating the microbial community and water quality performance of full-scale slow sand filters in laboratory-scale filters.

    Science.gov (United States)

    Haig, Sarah-Jane; Quince, Christopher; Davies, Robert L; Dorea, Caetano C; Collins, Gavin

    2014-09-15

    Previous laboratory-scale studies to characterise the functional microbial ecology of slow sand filters have suffered from methodological limitations that could compromise their relevance to full-scale systems. Therefore, to ascertain if laboratory-scale slow sand filters (L-SSFs) can replicate the microbial community and water quality production of industrially operated full-scale slow sand filters (I-SSFs), eight cylindrical L-SSFs were constructed and were used to treat water from the same source as the I-SSFs. Half of the L-SSFs sand beds were composed of sterilized sand (sterile) from the industrial filters and the other half with sand taken directly from the same industrial filter (non-sterile). All filters were operated for 10 weeks, with the microbial community and water quality parameters sampled and analysed weekly. To characterize the microbial community phyla-specific qPCR assays and 454 pyrosequencing of the 16S rRNA gene were used in conjunction with an array of statistical techniques. The results demonstrate that it is possible to mimic both the water quality production and the structure of the microbial community of full-scale filters in the laboratory - at all levels of taxonomic classification except OTU - thus allowing comparison of LSSF experiments with full-scale units. Further, it was found that the sand type composing the filter bed (non-sterile or sterile), the water quality produced, the age of the filters and the depth of sand samples were all significant factors in explaining observed differences in the structure of the microbial consortia. This study is the first to the authors' knowledge that demonstrates that scaled-down slow sand filters can accurately reproduce the water quality and microbial consortia of full-scale slow sand filters. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Drawer compacted sand filter: a new and innovative method for on-site grey water treatment.

    Science.gov (United States)

    Assayed, Almoayied; Chenoweth, Jonathan; Pedley, Steven

    2014-01-01

    In this paper, results ofa new sand filter design were presented. The drawer compacted sand filter (DCSF) is a modified design for a sand filter in which the sand layer is broken down into several layers, each of which is 10 cm high and placed in a movable drawer separated by a 10 cm space. A lab-scale DCSF was designed and operated for 330 days fed by synthetic grey water. The response of drawer sand filters to variable hydraulic and organic loading rates (HLR and OLR) in terms of biological oxygen demand (BODs), chemical oxygen demand (COD), total suspended solids (TSS), pH, electrical conductivity and Escherichia coli reductions were evaluated. The HLR was studied by increasing from 72 to 142 L m(-2) day(-1) and OLR was studied by increasing it from 23 to 30 g BOD5 m(-2) day(-1) while keeping the HLR constant at 142 L m(-2) day(-1). Each loading regime was applied for 110 days. Results showed that DCSF was able to remove >90% of organic matter and total suspended solids for all doses. No significant difference was noticed in terms of overall filter efficiency between different loads for all parameters. Significant reduction in BOD5 and COD (P water was drained through the third drawer in all tested loads. The paper concludes that DCSF would be appropriate for use in dense urban areas as its footprint is small and is appropriate for a wide range of users because of its convenience and low maintenance requirements.

  20. Barley root hair growth and morphology in soil, sand, and water solution media and relationship with nickel toxicity.

    Science.gov (United States)

    Lin, Yanqing; Allen, Herbert E; Di Toro, Dominic M

    2016-08-01

    Barley, Hordeum vulgare (Doyce), was grown in the 3 media of soil, hydroponic sand solution (sand), and hydroponic water solution (water) culture at the same environmental conditions for 4 d. Barley roots were scanned, and root morphology was analyzed. Plants grown in the 3 media had different root morphology and nickel (Ni) toxicity response. Root elongations and total root lengths followed the sequence soil > sand > water. Plants grown in water culture were more sensitive to Ni toxicity and had greater root hair length than those from soil and sand cultures, which increased root surface area. The unit root surface area as root surface area per centimeter of length of root followed the sequence water > sand > soil and was found to be related with root elongation. Including the unit root surface area, the difference in root elongation and 50% effective concentration were diminished, and percentage of root elongations can be improved with a root mean square error approximately 10% for plants grown in different media. Because the unit root surface area of plants in sand culture is closer to that in soil culture, the sand culture method, not water culture, is recommended for toxicity parameter estimation. Environ Toxicol Chem 2016;35:2125-2133. © 2016 SETAC. © 2016 SETAC.

  1. Importance of copper for nitrification in biological rapid sand filters for drinking water production

    DEFF Research Database (Denmark)

    Wagner, Florian Benedikt

    When anoxic groundwater is treated to produce drinking water, ammonium is commonly removed through nitrification in rapid sand filters. Nitrification is a biological process, and is mediated by chemoautotrophic microorganisms. Ammonia oxidizing bacteria (AOB) and archaea (AOA) oxidize ammonium...... to remove ammonium to below the national drinking water quality standard of 0.05 mg NH4+/L. A better process understanding of nitrifying biofilters is needed to optimize treatment performance, remediate existing filters, and to prevent future nitrification problems. The frequent incidents of insufficient...... in the oxidation of ammonia to hydroxylamine. Thus, slow and incomplete nitrification could be caused by a lack of sufficient amounts of copper. The overall aim of this PhD project was therefore to determine whether copper supplementation could enhance nitrification in rapid sand filters with incomplete...

  2. Sources and processes affecting the spatio-temporal distribution of pharmaceuticals and X-ray contrast media in the water resources of the Lower Jordan Valley, Jordan.

    Science.gov (United States)

    Zemann, Moritz; Wolf, Leif; Pöschko, Antje; Schmidt, Natalie; Sawarieh, Ali; Seder, Nayef; Tiehm, Andreas; Hötzl, Heinz; Goldscheider, Nico

    2014-08-01

    The closed basin of the Lower Jordan Valley with the Dead Sea as final sink features high evapotranspiration rates and almost complete reuse of treated wastewater for irrigation farming. This study focuses on the water transfer schemes and the presence, spreading, and potential accumulation of pharmaceutical residues in the local water resources based on findings of a five-year monitoring program. Overall 16 pharmaceuticals and 9 iodinated X-ray contrast media were monitored in groundwater, surface water, and treated wastewater. A total of 95 samples were taken to cover all geographical settings and flow paths from origin (wastewater) to target (groundwater). Nine substances were detected in groundwater, with concentrations ranging between 11 ng/L and 33,000 ng/L. Sometimes, detection rates were higher than in comparable studies: Diatrizoic acid 75%, iopamidol 42%, iopromide 19%, iomeprol 11%, carbamazepine and iohexol 8%, ibuprofen 6%, and fenofibrate and iothalamic acid 3%. Concentrations in groundwater generally increase from north to south depending on the application of treated wastewater for irrigation. Almost all substances occurred most frequently and with highest concentrations in treated wastewater, followed by surface water and groundwater. As exception, diatrizoic acid was found more frequently in groundwater than in treated wastewater, with concentrations being similar. This indicates the persistence of diatrizoic acid with long residence times in local groundwater systems, but may also reflect changing prescription patterns, which would be in accordance with increasing iopamidol findings and surveys at local hospitals. Trend analyses confirm this finding and indicate a high probability of increasing iopamidol concentrations, while other substances did not reveal any trends. However, no proof of evaporative enrichment could be found. The high spatial and temporal variability of the concentrations measured calls for further systematic studies to assess

  3. Nickel removal from nickel plating waste water using a biologically active moving-bed sand filter.

    Science.gov (United States)

    Pümpel, Thomas; Macaskie, Lynne E; Finlay, John A; Diels, Ludo; Tsezos, Marios

    2003-12-01

    Efficient removal of dissolved nickel was observed in a biologically active moving-bed 'MERESAFIN' sand filter treating rinsing water from an electroless nickel plating plant. Although nickel is fully soluble in this waste water, its passage through the sand filter promoted rapid removal of approximately 1 mg Ni/l. The speciation of Ni in the waste water was modelled; the most probable precipitates forming under the conditions in the filter were predicted using PHREEQC. Analyses of the Ni-containing biosludge using chemical, electron microscopical and X-ray spectroscopic techniques confirmed crystallisation of nickel phosphate as arupite (Ni3(PO4)2 x 8H2O), together with hydroxyapatite within the bacterial biofilm on the filter sand grains. Biosorption contributed less than 1% of the overall sequestered nickel. Metabolising bacteria are essential for the process; the definitive role of specific components of the mixed population is undefined but the increase in pH promoted by metabolic activity of some microbial components is likely to promote nickel desolubilisation by others.

  4. 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

  5. Retention of radium from thermal waters on sand filters and adsorbents

    International Nuclear Information System (INIS)

    Elejalde, C.; Herranz, M.; Idoeta, R.; Legarda, F.; Romero, F.; Baeza, A.

    2007-01-01

    This study was focussed on laboratory experiences of retention of radium from one thermal water on sand filters and adsorbents, trying to find an easy method for the elimination in drinkable waters polluted with this natural radio-nuclide. A thermal water from Cantabria (Spain) was selected for this work. Retention experiences were made with columns of 35 mm of diameter containing 15 cm layers of washed river sand or 4 cm layers of zeolite A3, passing known volumes of thermal water at flows between 4 and 40 ml/min with control of the retained radium by determining the amount in the water after the treatment. The statistical analysis of data suggests that retention depends on the flow and the volume passed through the columns. As additional adsorbents were used kaolin and a clay rich in illite. Jar-test experiences were made agitating known weights of adsorbents with the selected thermal water, with addition of flocculants and determination of radium in filtrated water after the treatment. Data suggest that retention is related to the weight of adsorbent used, but important quantities of radium seem remain in solution for higher amounts of adsorbents, according to the statistical treatment of data. The elution of retained radium from columns or adsorbents, previously used in experiences, should be the aim of a future research

  6. Retention of radium from thermal waters on sand filters and adsorbents

    Energy Technology Data Exchange (ETDEWEB)

    Elejalde, C. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain)]. E-mail: inpelsac@bi.ehu.es; Herranz, M. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Idoeta, R. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Legarda, F. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Romero, F. [Dpto. de Ingenieria Quimica y del Medio Ambiente, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Baeza, A. [Dpto. de Fisica, Facultad de Veterinaria, Universidad de Extremadura, Avda. Universidad s/n, 10071 Caceres (Spain)

    2007-06-18

    This study was focussed on laboratory experiences of retention of radium from one thermal water on sand filters and adsorbents, trying to find an easy method for the elimination in drinkable waters polluted with this natural radio-nuclide. A thermal water from Cantabria (Spain) was selected for this work. Retention experiences were made with columns of 35 mm of diameter containing 15 cm layers of washed river sand or 4 cm layers of zeolite A3, passing known volumes of thermal water at flows between 4 and 40 ml/min with control of the retained radium by determining the amount in the water after the treatment. The statistical analysis of data suggests that retention depends on the flow and the volume passed through the columns. As additional adsorbents were used kaolin and a clay rich in illite. Jar-test experiences were made agitating known weights of adsorbents with the selected thermal water, with addition of flocculants and determination of radium in filtrated water after the treatment. Data suggest that retention is related to the weight of adsorbent used, but important quantities of radium seem remain in solution for higher amounts of adsorbents, according to the statistical treatment of data. The elution of retained radium from columns or adsorbents, previously used in experiences, should be the aim of a future research.

  7. Quantifying the Effect of Soil Water Repellency on Infiltration Parameters Using a Dry Sand

    Science.gov (United States)

    Shillito, R.; Berli, M.; Ghezzehei, T. A.; Kaminski, E.

    2017-12-01

    Water infiltration into less than perfectly wettable soils has usually been considered an exceptional case—in fact, it may be the rule. Infiltration into soils exhibiting some degree of water repellency has important implications in agricultural irrigation, post-fire runoff, golf course and landscape management, and spill and contaminant mitigation. Beginning from fundamental principles, we developed a physically-based model to quantify the effect of water repellency on infiltration parameters. Experimentally, we used a dry silica sand and treated it to achieve various known degrees of water repellency. The model was verified using data gathered from multiple upward infiltration (wicking) experiments using the treated sand. The model also allowed us to explore the effect of initial soil moisture conditions on infiltration into water-repellent soils, and the physical interpretation of the simple water drop penetration time test. These results provide a fundamental step in the physically-based understanding of how water infiltrates into a less than perfectly wettable porous media.

  8. Research on the performance of sand-based environmental-friendly water permeable bricks

    Science.gov (United States)

    Cai, Runze; Mandula; Chai, Jinyi

    2018-02-01

    This paper examines the effects of the amount of admixture, the water cement ratio, the aggregate grading, and the cement aggregate ratio on the mechanical service properties and of porous concrete pavement bricks including strength, water permeability, frost resistance, and wear resistance. The admixture can enhance the performance of water permeable brick, and optimize the design mix. Experiments are conducted to determine the optimal mixing ratios which are given as; (1) the admixture (self-developed) within the content of 5% of the cement quality; (2) water-cement ratio equal to 0.34; (3) cement-aggregate ratio equal to 0.25; (4) fine aggregate of 70% (particle size 0.6-2.36mm); and coarse aggregate of 30% (particle size: 2.36-4.75mm). The experimental results that the sand-based permeable concrete pavement brick has a strength of 35.6MPa and that the water permeability coefficient is equal to 3.5×10-2cm/s. In addition, it was found that the concrete water permeable brick has good frost resistance and surface wear resistance, and that the its production costs are much lower than the similar sand-based water permeable bricks in China.

  9. Acidic deposition: State of science and technology. Report 10. Watershed and lake processes affecting surface-water acid-base chemistry. Final report

    International Nuclear Information System (INIS)

    Turner, R.S.; Cook, R.B.; Miegroet, H.V.; Johnson, D.W.; Elwood, J.W.

    1990-09-01

    The acid-base chemistry of surface waters is governed by the amount and chemistry of deposition and by the biogeochemical reactions that generate acidity or acid neutralizing capacity (ANC) along the hydrologic pathways that water follows through watersheds to streams and lakes. The amount of precipitation and it chemical loading depend on the area's climate and physiography, on it proximity to natural or industrial gaseous or particulate sources, and on local or regional air movements. Vegetation interacts with the atmosphere to enhance both wet and dry deposition of chemicals to a greater or lesser extent, depending on vegetation type. Vegetation naturally acidifies the environment in humid regions through processes of excess base cation uptake and generation of organic acids associated with many biological processes. Natural acid production and atmospheric deposition of acidic materials drive the acidification process. The lake or stream NAC represents a balance between the acidity-and ANC-generating processes that occur along different flow paths in the watershed and the relative importance of each flow path

  10. HYDRAULIC ELEVATOR INSTALLATION ESTIMATION FOR THE WATER SOURCE WELL SAND-PACK CLEANING UP

    Directory of Open Access Journals (Sweden)

    V. V. Ivashechkin

    2016-01-01

    Full Text Available The article offers design of a hydraulic elevator installation for cleaning up water-source wells of sand packs. It considerers the installation hydraulic circuit according to which the normal pump feeds the high-level tank water into the borehole through two parallel water lines. The water-jet line with washing nozzle for destroying the sand-pack and the supply pipe-line coupled with the operational nozzle of the hydraulic elevator containing the inlet and the supply pipelines for respectively intaking the hydromixture and removing it from the well. The paper adduces equations for fluid motion in the supply and the water-jet pipelines and offers expressions for evaluating the required heads in them. For determining water flow in the supply and the water-jet pipe lines the author proposes to employ graphical approach allowing finding the regime point in Q–H chart by means of building characteristics of the pump and the pipe-lines. For calculating the useful vertical head, supply and dimensions of the hydraulic elevator the article employs the equation of motion quantity with consistency admission of the motion quantity before and after mixing the flows in the hydraulic elevator. The suggested correlations for evaluating the hydraulic elevator efficiency determine the sand pack removal duration as function of its sizes and the ejected fluid flow rate. A hydraulic-elevator installation parameters estimation example illustrates removing a sand pack from a water-source borehole of 41 m deep and 150 mm diameter bored in the village of Uzla of Myadelsk region, of Minsk oblast. The working efficiency of a manufactured and laboratory tested engineering prototype of the hydraulic elevator installation was acknowledged in actual tests at the indicated borehole site. With application of graphical approach, the suggested for the hydraulic elevator installation parameters calculation procedure allows selecting, with given depth and the borehole diameter

  11. Influence of Geometric Parameters of the Hydrocyclone and Sand Concentration on the Water/Sand/Heavy-Oil Separation Process: Modeling and Simulation

    Directory of Open Access Journals (Sweden)

    F Farias

    2016-09-01

    Full Text Available In the oil exploitation, produced fluids are composed of oil, gas, water and sand (depending on the reservoir location. The presence of sand in flow oil leads to several industrial problems for example: erosion and accumulation in valves and pipeline. Thus, it is necessary to stop production for manual cleaning of equipments and pipes. These facts have attracted attention of academic and industrial areas, enabling the appearing of new technologies or improvement of the water/oil/sand separation process. One equipment that has been used to promote phase separation is the hydrocyclone due to high performance of separation and required low cost to installation and maintenance. In this sense, the purpose of this work is to study numerically the effect of geometric parameters (vortex finder diameter of the hydrocyclone and sand concentration on the inlet fluid separation process. A numerical solution of the governing equations was obtained by the ANSYS CFX-11 commercial code. Results of the streamlines, pressure drop and separation efficiency on the hydrocyclone are presented and analyzed. It was observed that the particles concentration and geometry affect the separation efficiency of the hydrocyclone.

  12. Seasonal energy, water, and food consumption of Negev Chukars and sand partridges

    International Nuclear Information System (INIS)

    Kam, M.; Degen, A.A.; Nagy, K.A.

    1987-01-01

    Chukars (Alectoris chukar) and Sand Partridges (Ammoperdix heyl), two ground-dwelling phasianids, are permanent residents of the Negev desert and are sympatric over much of their ranges. Sand Partridges (body mass = 150-250 g), however, inhabit only arid and very arid areas, whereas Chukars (m/sub b/ = 350-600 g) are widely distributed and inhabit deserts only at the margins of their ranges. They compared some of the desert adaptations of these phasianids by measuring the seasonal field metabolic rates (FMR) and water influxes (using doubly labelled water), diet selection, and food requirements of free-living Chukars and Sand Partridges at a site where both species occurred. Both species showed adaptation in the form of low energy metabolism, which ranged from 43 to 81% of that expected for birds of similar body mass. During summer, Sand Partridges had lower energy expenditures (5.47 kJ x g/sup -0.61/ x d -1 ) and water influxes (72.3 mL kg/sup -0.75/ d -1 ) than did Chukars (6.42 kJ g/sup -0.61/ d -1 and 93.5 mL x kg/sup -0.75/ x d -1 , respectively), indicating more pronounced adjustments to arid conditions in the desert specialist. However, both species obtained more than half of their water influx in summer by drinking. Their summer diet was relatively dry, consisting mainly of seeds (80%) along with some green vegetation (18%) and, in Chukars, occasional arthropods. This situation changed abruptly after winter rains, which induced germination and reduced the availability of seeds. Chukars were unable to maintain energy balance in the face of low ambient temperatures and a diet (90% green vegetation) that contained much water but comparatively little energy, and they mobilized fat reserves to meet energy requirements. Most Sand Partridges left the study area after winter rains, apparently migrating to the lower elevation, warmer, and drier Arava (part of the Rift Valley)

  13. ARSENIC REMOVAL FROM DRINKING WATER BY ADSORPTIVE MEDIA - USEPA DEMONSTRATION PROJECT AT DESERT SANDS MDWCA, NM SIX MONTH EVALUATION

    Science.gov (United States)

    This report documents the activities performed during, and the results obtained from, the first six months of the arsenic removal treatment technology demonstration project at the Desert Sands Mutual Domestic Water Consumers Association (MDWCA) facility in Anthony, NM. The object...

  14. Transport of 152Eu colloids in a system of fine sand and water containing humic substances

    International Nuclear Information System (INIS)

    Klotz, D.

    1995-01-01

    The migration of 152 Eu in a system of fine sand and water containing humic substances was investigated in a flow column system under realistic conditions. In this system, the trivalent Eu forms colloids with the water. These Eu humates are transported without retardation at recovery rates significantly below 100 per cent. Recovery is more or less a measure of the physical process of filtration of Eu bonded to particulates. In the range of natural filtering rates, the recovery rates decrease with decreasing filtering rate. (orig.) [de

  15. Effective removal of trace thallium from surface water by nanosized manganese dioxide enhanced quartz sand filtration.

    Science.gov (United States)

    Huangfu, Xiaoliu; Ma, Chengxue; Ma, Jun; He, Qiang; Yang, Chun; Zhou, Jian; Jiang, Jin; Wang, Yaan

    2017-12-01

    Thallium (Tl) has drawn wide concern due to its high toxicity even at extremely low concentrations, as well as its tendency for significant accumulation in the human body and other organisms. The need to develop effective strategies for trace Tl removal from drinking water is urgent. In this study, the removal of trace Tl (0.5 μg L -1 ) by conventional quartz sand filtration enhanced by nanosized manganese dioxide (nMnO 2 ) has been investigated using typical surface water obtained from northeast China. The results indicate that nMnO 2 enhanced quartz sand filtration could remove trace Tl(I) and Tl(III) efficiently through the adsorption of Tl onto nMnO 2 added to a water matrix and onto nMnO 2 attached on quartz sand surfaces. Tl(III)-HA complexes might be responsible for higher residual Tl(III) in the effluent compared to residual Tl(I). Competitive Ca 2+ cations inhibit Tl removal to a certain extent because the Ca 2+ ions will occupy the Tl adsorption site on nMnO 2 . Moreover, high concentrations of HA (10 mgTOC L -1 ), which notably complexes with and dissolves nMnO 2 (more than 78%), resulted in higher residual Tl(I) and Tl(III). Tl(III)-HA complexes might also enhance Tl(III) penetration to a certain extent. Additionally, a higher pH level could enhance the removal of trace Tl from surface water. Finally, a slight increase of residual Tl was observed after backwash, followed by the reduction of the Tl concentration in the effluent to a "steady" state again. The knowledge obtained here may provide a potential strategy for drinking water treatment plants threatened by trace Tl. Copyright © 2017. Published by Elsevier Ltd.

  16. Ground-water flow and quality in the Atlantic City 800-foot sand, New Jersey

    Science.gov (United States)

    McAuley, Steven D.; Barringer, Julia L.; Paulachok, Gary N.; Clark, Jeffrey S.; Zapecza, Otto S.

    2001-01-01

    The regional, confined Atlantic City 800-foot sand is the principal source of water supply for coastal communities of southern New Jersey. In response to extensive use of the aquifer--nearly 21 million gallons per day in 1986--water levels have declined to about 100 feet below sea level near Atlantic City and remain below sea level throughout the coastal areas of southern New Jersey, raising concerns about the potential for saltwater intrusion into well fields. Water levels in the Atlantic City 800-foot sand have declined in response to pumping from the aquifer since the 1890's. Water levels in the first wells drilled into the Atlantic City 800-foot sand were above land surface, and water flowed continuously from the wells. By 1986, water levels were below sea level throughout most of the coastal areas. Under current conditions, wells near the coast derive most of their supply from lateral flow contributed from the unconfined part of the aquifer northwest of the updip limit of the confining unit that overlies the Atlantic City 800- foot sand. Ground water also flows laterally from offshore areas and leaks vertically through the overlying and underlying confining units into the Atlantic City 800-foot sand. The decline in water levels upsets the historical equilibrium between freshwater and ancient saltwater in offshore parts of the aquifer and permits the lateral movement of saltwater toward pumping centers. The rate of movement is accelerated as the decline in water levels increases. The chloride concentration of aquifer water 5.3 miles offshore of Atlantic City was measured as 77 mg/L (milligrams per liter) in 1985 at a U.S. Geological Survey observation well. Salty water has also moved toward wells in Cape May County. The confined, regional nature of the Atlantic City 800-foot sand permits water levels in Cape May County to decline in response to pumping in Atlantic County and vice versa. Historically, chloride concentrations as great as 1 ,510 mg/L have been

  17. Evaluation of the MF/UF Performance for the Reuse of Sand Filter Backwash Water from Drinking Water Treatment Plants

    Directory of Open Access Journals (Sweden)

    Neda Shirzadi

    2015-05-01

    Full Text Available The aim of this study was to investigate the application of micro-filtration and ultra-filtration membrane systems in order to improve the physical and microbial quality and the reuse of backwash water from the sand filter units in water treatment plants. The backwash water from filters makes up for 3 to 5 percent of the total water treated, which is disposed in most WTPs. However, the treatment and reuse of the backwash water is more admissible from technical and economic viewpoints, especially in view of the present water scarcity. For the purposes of this study, use was made of membrane modules of micro- and ultra-filters on a pilot scale. The micro-filter employed consisted of a polypropylene membrane module with a porosity of 1 micron in size and a fiberglass module with a porosity of 5 microns. The ultra-filter was made of PVC hollow fiber with a molecular weight of 100,000 Dalton. In order to feed the two pilots, backwash water from a sand filter was collected from one of the WTPs in Tehran. After samples were taken from the backwash water, the physical and microbial removal efficiency was periodically evaluated based on the standard method and the micro-filtration, ultra-filtration, and combined MF/UF processes were compared with respect to their performance. The results indicate that the combined MF/UF process is able to decrease turbidity, MPN, COD, TSS, and Fe with efficiency values of 99.9, 100, 61.5, 99.9 and 98.8 percent, respectively. Overall, the findings confirmed the technical capabilities of this method for the recovery and reuse of the effluent produced in the backwashing mechanism of sand filters in WTPs.

  18. Manganese Coated Sand for Copper (II Removal from Water in Batch Mode

    Directory of Open Access Journals (Sweden)

    Nidal Hilal

    2013-09-01

    Full Text Available Removal of heavy metals, such as copper ions, from water is important to protect human health and the environment. In this study, manganese coated sand (MCS was used as an adsorbent to remove copper ions in a batch system. Equilibrium data were determined at a temperature of 25.6 °C and the Langmuir model was used to describe the experimental data. Mn-coating improved the removal of copper ions by 70% as compared to uncoated sand. Based on a kinetics study, the adsorption of copper ions on MCS was found to occur through a chemisorption process and the pseudo-second-order model was found to fit the kinetics experimental data well. Due to particle interactions, the equilibrium uptake was reduced as the ratio of sand to volume of solution increased. pH affected the removal of copper ions with lowest uptakes found at pH 3 and pHs >7, whilst at pHs in the range of 4 to 7, the uptake was highest and almost constant at the value of 0.0179 mg/g ± 4%. This study has also revealed that copper ions removal was dissolved oxygen (DO dependent with the highest removal occurring at ambient DO concentration, which suggests that DO should be carefully studied when dealing with copper ions adsorption.

  19. Hydrogeochemical contrast between brown and grey sand aquifers in shallow depth of Bengal Basin: consequences for sustainable drinking water supply.

    Science.gov (United States)

    Biswas, Ashis; Nath, Bibhash; Bhattacharya, Prosun; Halder, Dipti; Kundu, Amit K; Mandal, Ujjal; Mukherjee, Abhijit; Chatterjee, Debashis; Mörth, Carl-Magnus; Jacks, Gunnar

    2012-08-01

    Delineation of safe aquifer(s) that can be targeted by cheap drilling technology for tubewell (TW) installation becomes highly imperative to ensure access to safe and sustainable drinking water sources for the arsenic (As) affected population in Bengal Basin. This study investigates the potentiality of brown sand aquifers (BSA) as a safe drinking water source by characterizing its hydrogeochemical contrast to grey sand aquifers (GSA) within shallow depth (water guidelines, which warrants rigorous assessment of attendant health risk for Mn prior to considering mass scale exploitation of the BSA for possible sustainable drinking water supply. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Phosphate limitation in biological rapid sand filters used to remove ammonium from drinking water

    DEFF Research Database (Denmark)

    Lee, Carson Odell; Albrechtsen, Hans-Jørgen; Smets, Barth F.

    2013-01-01

    Removing ammonium from drinking water is important for maintaining biological stability in distribution systems. This is especially important in regions that do not use disinfectants in the treatment process or keep a disinfectant residual in the distribution system. Problems with nitrification c...... a pilot scale sand column which initial analysis confirmed performed similarly to the full scale filters. Long term increased ammonium loads were applied to the pilot filter both with and without phosphate addition. Phosphate was added at a concentration of 0.5 mg PO4-P/L to ensure...

  1. 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.

  2. Arsenic removal from drinking water by a household sand filter in Vietnam--effect of filter usage practices on arsenic removal efficiency and microbiological water quality.

    Science.gov (United States)

    Nitzsche, Katja Sonja; Lan, Vi Mai; Trang, Pham Thi Kim; Viet, Pham Hung; Berg, Michael; Voegelin, Andreas; Planer-Friedrich, Britta; Zahoransky, Jan; Müller, Stefanie-Katharina; Byrne, James Martin; Schröder, Christian; Behrens, Sebastian; Kappler, Andreas

    2015-01-01

    Household sand filters are applied to treat arsenic- and iron-containing anoxic groundwater that is used as drinking water in rural areas of North Vietnam. These filters immobilize poisonous arsenic (As) via co-oxidation with Fe(II) and sorption to or co-precipitation with the formed Fe(III) (oxyhydr)oxides. However, information is lacking regarding the effect of the frequency and duration of filter use as well as of filter sand replacement on the residual As concentrations in the filtered water and on the presence of potentially pathogenic bacteria in the filtered and stored water. We therefore scrutinized a household sand filter with respect to As removal efficiency and the presence of fecal indicator bacteria in treated water as a function of filter operation before and after sand replacement. Quantification of As in the filtered water showed that periods of intense daily use followed by periods of non-use and even sand replacement did not significantly (psand replacement, CFUs of Escherichia coli of sand filters regarding As removal, but indicate a potential risk for human health arising from the enrichment of coliform bacteria during filtration and from E. coli cells that are introduced by sand replacement. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Predicted water quality of oil sands reclamation wetlands : impact of physical design and hydrology

    International Nuclear Information System (INIS)

    2006-01-01

    Although engineered wetlands can be used as treatment systems in the reclamation of oil sands mines, a variety of factors must be considered to improve the biological functioning of many oil sands reclamation landscapes. Key factors in the control of concentrations of dissolved substances include area, depth, shape, surrounding landscape material and contributing water quality and quantity. Seasonal cycles of precipitation and ice cover also require consideration in the planning of wetlands ecosystems. This paper presented details of a model designed to predict constituent concentrations in planned wetlands based on probable inflow and processes. Input variables consisted of key substances and hydrological factors that may be encountered on reclaimed landscapes. The model was constructed to perform sensitivity analyses of wetlands with respect to total dissolved solids (TDS), major ions, and naphthenic acids concentrations. Inputs and assumptions drawn from previous environmental impact assessments completed for proposed and approved oil sands projects were used. Results suggested that wetlands volume is an important factor in the moderation of peak flows and substance decay. The predictions generated by the model suggested that wetlands size, tailings and sandcap placement schedules may be manipulated to achieve desired wetlands salinities. It was observed that the proportion of the watershed covered by specific land types can affect both initial and future concentrations. Long-term climate change that results in 15 per cent more or less runoff was predicted to have little effect on wetlands concentrations, although concentrations may rise during periodic droughts. It was concluded that site-specific modelling and careful planning is needed to achieve desired water quality for the creation of engineered wetlands. 18 refs., 3 tabs., 3 figs

  4. Estimation of uranium in different types of water and sand samples by adsorptive stripping voltammetry

    International Nuclear Information System (INIS)

    Bhalke, Sunil; Raghunath, Radha; Mishra, Suchismita; Suseela, B.; Tripathi, R.M.; Pandit, G.G.; Shukla, V.K.; Puranik, V.D.

    2005-01-01

    A method is standardized for the estimation of uranium by adsorptive stripping voltammetry using chloranilic acid (CAA) as complexing agent. The optimum parameters to get best sensitivity and good reproducibility for uranium were 60s adsorption time, pH 1.8, chloranilic acid (2x10 -4 M) and 0.002M EDTA. The peak potential under this condition was found to be -0.03 V. With these optimum parameters a sensitivity of 1.19 nA/nM uranium was observed. Detection limit for this optimum parameter was found to be 0.55 nM. This can be further improved by increasing adsorption time. Using this method, uranium was estimated in different type of water samples such as seawater, synthetic seawater, stream water, tap water, well water, bore well water and process water. This method has also been used for estimation of uranium in sand, organic solvent used for extraction of uranium from phosphoric acid and its raffinate. Sample digestion procedures used for estimation of uranium in various matrices are discussed. It has been observed from the analysis that the uranium peak potentials changes with matrix of the sample, hence, standard addition method is the best method to get reliable and accurate results. Quality assurance of the standardized method is verified by analyzing certified reference water sample from USDOE, participating intercomparison exercises and also by estimating uranium content in water samples both by differential pulse adsorptive stripping voltammetric and laser fluorimetric techniques. (author)

  5. Measurements of distribution coefficient for U and Th on sand stone in synthesized sea water and distilled water

    International Nuclear Information System (INIS)

    Nakazawa, Toshiyuki; Okada, Kenichi; Saito, Yoshihiko; Shibata, Masahiro; Sasamoto, Hiroshi

    2005-01-01

    Japan Nuclear Cycle Development Institute (JNC) has developed the sorption database for bentonite and rocks in order to assess the retardation property of important radioactive elements in natural and engineered barriers in the H12 report. However, there are not enough distribution coefficient data for radioactive elements in saline type groundwater in the database. Thus the batch sorption tests were performed for uranium (U) and thorium (Th) in saline type groundwater. For these elements, there are little registration numbers in the JNC's sorption database, and also these elements are important to evaluate the safety of disposal system. The experiments for each radioactive element were performed on the following conditions; U: Kd measurements using the solutions (synthesized sea water and distilled water) reacted with sand stone as a function of carbonate concentration, under reducing conditions. Th: Kd measurements using the solutions (synthesized sea water and distilled water) reacted with sand stone. The results of the experiments are summarized below; In the case of U, Kd was approximately 6.5E-01 - 9.2E-01 m 3 /kg in synthesized sea water. On the other hand, Kd was 2.2E-02 - 2.4E-02 m 3 /kg in the high carbonate solution. And also, Kd was 6.5E-02 - 7.2E-02 m 3 /kg in synthesized sea water adjusted pH 10 and 3.4E-02 - 4.1E-02 m 3 /kg in distilled water adjusted pH 10, respectively. In the case of Th, Kd was measured in synthesized sea water adjusted to pH 10 and in distilled water adjusted to pH 10. At the sorption measurements of Th, precipitation might be occurred by very low solubility of Th. (author)

  6. Investigating salt and naphthenic acids interactions in the toxicity of oil sands process water to freshwater invertebrates

    International Nuclear Information System (INIS)

    Turcotte, D.; Kautzman, M.; Wojnarowicz, P.; Cutter, J.; Bird, E.; Liber, K.

    2010-01-01

    The hot water extraction process used to produce bitumens from oil sands produces a large volume of oil sands process water (OSPW) that contain elevated concentrations of naphthenic acids (NA) and salts. Many oil sands reclamation projects are proposing the use of OSPW as part of reconstructed wetlands projects. This study investigated the toxicity of OSPW to freshwater invertebrates. The toxic interactions between NA and salinity on freshwater invertebrates were assessed. Bioassays with laboratory-cultured Ceriodaphnia dubia were conducted to determine the toxicity of OSPW from selected water bodies. The study showed that while the concentrations of NAs and salinity were elevated in OSPW waters that caused toxic responses, the concentrations of salinity ions varied greatly among the OSPW samples. Results of the study suggested that ion composition may be a factor in toxicity. Interactions between NAs and salinity were then assessed by performing bioassays with mixtures representing major ion combinations in OSPW.

  7. Water Flow Investigation on Quartz Sand with 13-interval Stimulated Echo Multi Slice Imaging

    Science.gov (United States)

    Spindler, Natascha; Pohlmeier, Andreas; Galvosas, Petrik

    2011-03-01

    Understanding root water uptake in soils is of high importance for securing nutrition in the context of climate change and linked phenomena like stronger varying weather conditions (draught, strong rain). One step to understand how root water uptake occurs is the knowledge of the water flow in soil towards plant roots. Magnetic Resonance Imaging (MRI) in combination with q-space imaging is potentially the most powerful analytical tool for non-invasive three dimensional visualization of flow and transport in porous media. Numerous attempts have been made to measure local velocity in porous media by combining velocity phase encoding with fast imaging methods, where flow velocities in the vascular bundles of plant stems were investigated. In contrast to water situated in the cellular structure of plants, NMR signal arising from water in the pore space in soil may be much more affected by the presence of internal magnetic field gradients. In this work we account for the existence of these gradients by employing bipolar pulsed field magnetic gradients for velocity encoding. This enables one to study flow through sand (as a model system for soil) at flow rates relevant for the water uptake of plant roots.

  8. Responses of woody species to spatial and temporal ground water changes in coastal sand dune systems

    Science.gov (United States)

    Máguas, C.; Rascher, K. G.; Martins-Loução, A.; Carvalho, P.; Pinho, P.; Ramos, M.; Correia, O.; Werner, C.

    2011-12-01

    In spite of the relative importance of groundwater in costal dune systems, studies concerning the responses of vegetation to ground water (GW) availability variations, particularly in Mediterranean regions, are scarce. Thus, the main purpose of this study is to compare the responses of co-occurring species possessing different functional traits, to changes in GW levels (i.e. the lowering of GW levels) in a sand dune ecosystem. For that, five sites were established within a 1 km2 area in a meso-mediterranean sand dune ecosystem dominated by a Pinus pinaster forest. Due to natural topographic variability and anthropogenic GW exploitation, substantial variability in depth to GW between sites was found. Under these conditions it was possible to identify the degree of usage and dependence on GW of different plant species (two deep-rooted trees, a drought adapted shrub, a phreatophyte and a non-native woody invader) and how GW dependence varied seasonally and between the heterogeneous sites. Results indicated that the plant species had differential responses to changes in GW depth according to specific functional traits (i.e. rooting depth, leaf morphology, and water use strategy). Species comparison revealed that variability in pre-dawn water potential (Ψpre) and bulk leaf δ13C was related to site differences in GW use in the deep-rooted (Pinus pinaster, Myrica faya) and phreatophyte (Salix repens) species. However, such variation was more evident during spring than during summer drought. The exotic invader, Acacia longifolia, which does not possess a very deep root system, presented the largest seasonal variability in Ψpre and bulk leaf δ13C. In contrast, the response of Corema album, an endemic understory drought-adapted shrub, seemed to be independent of water availability across seasons and sites. Thus, the susceptibility to lowering of GW due to anthropogenic exploitation, in plant species from sand dunes, is variable, being particularly relevant for deep

  9. Responses of woody species to spatial and temporal ground water changes in coastal sand dune systems

    Directory of Open Access Journals (Sweden)

    C. Máguas

    2011-12-01

    Full Text Available In spite of the relative importance of groundwater in costal dune systems, studies concerning the responses of vegetation to ground water (GW availability variations, particularly in Mediterranean regions, are scarce. Thus, the main purpose of this study is to compare the responses of co-occurring species possessing different functional traits, to changes in GW levels (i.e. the lowering of GW levels in a sand dune ecosystem. For that, five sites were established within a 1 km2 area in a meso-mediterranean sand dune ecosystem dominated by a Pinus pinaster forest. Due to natural topographic variability and anthropogenic GW exploitation, substantial variability in depth to GW between sites was found. Under these conditions it was possible to identify the degree of usage and dependence on GW of different plant species (two deep-rooted trees, a drought adapted shrub, a phreatophyte and a non-native woody invader and how GW dependence varied seasonally and between the heterogeneous sites. Results indicated that the plant species had differential responses to changes in GW depth according to specific functional traits (i.e. rooting depth, leaf morphology, and water use strategy. Species comparison revealed that variability in pre-dawn water potential (Ψpre and bulk leaf δ13C was related to site differences in GW use in the deep-rooted (Pinus pinaster, Myrica faya and phreatophyte (Salix repens species. However, such variation was more evident during spring than during summer drought. The exotic invader, Acacia longifolia, which does not possess a very deep root system, presented the largest seasonal variability in Ψpre and bulk leaf δ13C. In contrast, the response of Corema album, an endemic understory drought-adapted shrub, seemed to be independent of water availability across seasons and sites. Thus, the susceptibility to lowering of GW due to anthropogenic

  10. Innovative in-line separators: removal of water or sand in oil/water and gas/liquid/solid pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Jepson, Paul; Cheolho Kang; Gopal, Madan [CC Technologies, Dublin, OH (United States)

    2003-07-01

    In oil and gas production, multiphase mixtures are often separated before downstream processing. The separators are large, often 20 - 40 feet long and large diameter and use sophisticated internals. The costs are in the millions of dollars. Further, the sand and water in the flow can cause severe internal erosion and corrosion respectively before the flow reaches the separators. The CC Technologies/MIST In line Separation System is a cost-effective, efficient device for use in multiphase environments. The device is applicable for gas/solid, gas/liquid/solid and oil/water systems and offers exceptional separation between phases for a fraction of the cost of expensive gravity separators and hydro cyclones. The System contains no moving parts and is designed to be of the same diameter as the pipe, and experiences low shear forces. It can be fabricated with standard pipes. The efficiency of the separator has been determined in an industrial scale, pilot plant test facility at CC Technologies in 4-inch diameter pipes and has been found to be in excess of 98-99% for the removal of sand. Two phase oil/water separation effectiveness is in excess of 90% in 1-stage and 95% in 2 - stage. (author)

  11. 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

  12. 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.

  13. Growth of Chironomus dilutus larvae exposed to ozone-treated and untreated oil sands process water

    International Nuclear Information System (INIS)

    Anderson, J.; Wiseman, S.; Franz, E.; Jones, P.; Liber, K.; Giesy, J.; Gamal El-Din, M.; Marin, J.

    2010-01-01

    Oil sand processing operations require large quantities of freshwater and produce large volumes of oil sands process water (OSPW) which must be stored on-site. This presentation reviewed various treatment methods for remediating OSPW in order to eliminate downstream toxicity. Naphthenic acids are the most important target fractions for treatment because they are primarily responsible for the acute toxicity of OSPW. Although ozonation has shown promise for reducing OSPW toxicity, the effects of ozonation on aquatic invertebrates remain unknown. This study investigated the effects of exposure to untreated and ozonated OSPW in Chironomus dilutus larvae. OSPW was treated with either a 50 or 80 mg O 3 /L dose of ozonation. The effects of ozonation levels on C. dilutus survival and growth were examined. The study showed that after a 10-day exposure, there were pronounced effects on survival of larvae exposed to ozone-treated or untreated OSPW. Larvae exposed to OSPW were 64-77 percent smaller than their respective controls, but the mean wet mass of organisms exposed to 50 mg O 3 /L ozonated OSPW was not much different from that of the controls. Larvae exposed to 80 mg O 3 /L ozone-treated OSPW were 40 percent smaller than the freshwater controls, and the mean wet mass was also much larger than the untreated OSPW. It was concluded that the toxicity of OSPW to benthic invertebrates may be reduced by ozone treatment.

  14. Study on Water Distribution Imaging in the Sand Using Propagation Velocity of Sound with Scanning Laser Doppler Vibrometer

    Science.gov (United States)

    Sugimoto, Tsuneyoshi; Nakagawa, Yutaka; Shirakawa, Takashi; Sano, Motoaki; Ohaba, Motoyoshi; Shibusawa, Sakae

    2013-07-01

    We propose a method for the monitoring and imaging of the water distribution in the rooting zone of plants using sound vibration. In this study, the water distribution measurement in the horizontal and vertical directions in the soil layer was examined to confirm whether a temporal change in the volume water content of the soil could be estimated from a temporal changes in propagation velocity. A scanning laser Doppler vibrometer (SLDV) is used for measurement of the vibration velocity of the soil surface, because the highly precise vibration velocity measurement of several many points can be carried out automatically. Sand with a uniform particle size distribution is used for the soil, as it has high plasticity; that is, the sand can return to a dry state easily even if it is soaked with water. A giant magnetostriction vibrator or a flat speaker is used as a sound source. Also, a soil moisture sensor, which measures the water content of the soil using the electric permittivity, is installed in the sand. From the experimental results of the vibration measurement and soil moisture sensors, we can confirm that the temporal changes of the water distribution in sand using the negative pressure irrigation system in both the horizontal and vertical directions can be estimated using the propagation velocity of sound. Therefore, in the future, we plan to develop an insertion-type sound source and receiver using the acceleration sensors, and we intend to examine whether our method can be applied even in commercial soil with growing plants.

  15. Sand consolidation

    Energy Technology Data Exchange (ETDEWEB)

    Spain, H H

    1965-01-21

    In a sand consolidation method in which there is injected a mixture of resin-forming liquids comprising an aryl-hydroxy low molecular weight compound, a water- soluble aldehyde, and a catalyst, an improvement is claimed which comprises diluting the resin-forming liquids with a diluent and with water so that the yield of the resin is sufficient to consolidate the sand particles with the minimum desirable pressure. The diluent may be mutually soluble in water and in the resin-forming liquids, and does not affect the setting time of the polymer. The aldehyde and the aryl-hydroxy compound may be in ratio of 5:1, and the diluent, methyl alcohol, is present in a ratio of 2:1 with reference to the water.

  16. Assessment of oil sand process water toxicity in wetlands of northern Alberta using Chironomid mentum deformities

    Energy Technology Data Exchange (ETDEWEB)

    Whelly, M. P.; Ciborowski, J. J. H. [Windsor, Univ., Windsor, ON (Canada)

    1998-07-01

    The effects of oil sands process water (OSPW) on aquatic invertebrates in wetlands near Fort McMurray, Alberta, are assessed. Principal components analysis and cluster analysis of environmental characteristics of 15 wetlands were used to identify three pairs of environmentally similar wetlands that differed mainly in exposure to or absence of OSPW. Large larvae of Chironomidae were collected and examined for mentum deformities (missing or extra teeth) for use as a biomarker. Invertebrate taxa richness and abundance was only moderately lower at OSPW -affected sites than at corresponding reference sites. The incidence of teeth deformities in midges (Chironomidae spp.) from OSPW-affected and corresponding reference wetlands was found to be moderate, and homogeneous among sites and between paired reference and OSPW-affected wetlands. This finding led to the conclusion that the suspected trace metals and PAHs may not be bioavailable in these highly humic wetlands.

  17. Assessment of oil sand process water toxicity in wetlands of northern Alberta using Chironomid mentum deformities

    Energy Technology Data Exchange (ETDEWEB)

    Whelly, M. P.; Ciborowski, J. J. H. [Windsor, Univ., Windsor, ON (Canada)

    1998-12-31

    The effects of oil sands process water (OSPW) on aquatic invertebrates in wetlands near Fort McMurray, Alberta, are assessed. Principal components analysis and cluster analysis of environmental characteristics of 15 wetlands were used to identify three pairs of environmentally similar wetlands that differed mainly in exposure to or absence of OSPW. Large larvae of Chironomidae were collected and examined for mentum deformities (missing or extra teeth) for use as a biomarker. Invertebrate taxa richness and abundance was only moderately lower at OSPW -affected sites than at corresponding reference sites. The incidence of teeth deformities in midges (Chironomidae spp.) from OSPW-affected and corresponding reference wetlands was found to be moderate, and homogeneous among sites and between paired reference and OSPW-affected wetlands. This finding led to the conclusion that the suspected trace metals and PAHs may not be bioavailable in these highly humic wetlands.

  18. Assessment of oil sand process water toxicity in wetlands of northern Alberta using Chironomid mentum deformities

    International Nuclear Information System (INIS)

    Whelly, M. P.; Ciborowski, J. J. H.

    1998-01-01

    The effects of oil sands process water (OSPW) on aquatic invertebrates in wetlands near Fort McMurray, Alberta, are assessed. Principal components analysis and cluster analysis of environmental characteristics of 15 wetlands were used to identify three pairs of environmentally similar wetlands that differed mainly in exposure to or absence of OSPW. Large larvae of Chironomidae were collected and examined for mentum deformities (missing or extra teeth) for use as a biomarker. Invertebrate taxa richness and abundance was only moderately lower at OSPW -affected sites than at corresponding reference sites. The incidence of teeth deformities in midges (Chironomidae spp.) from OSPW-affected and corresponding reference wetlands was found to be moderate, and homogeneous among sites and between paired reference and OSPW-affected wetlands. This finding led to the conclusion that the suspected trace metals and PAHs may not be bioavailable in these highly humic wetlands

  19. Effects of water content on reactive transport of Sr in Chernobyl sand columns

    International Nuclear Information System (INIS)

    Szenknect, S.; Dewiere, L.; Ardois, C.; Gaudet, J.P.

    2005-01-01

    Full text of publication follows: While transport of non-reactive solutes has been studied extensively in unsaturated porous media, much less is known about the factors that control the transport of sorbing solutes in unsaturated conditions. Three laboratory techniques were used to analyze the transport of Sr in the aeolian sand from Chernobyl Pilot Site [1] in both saturated and unsaturated flow conditions. Batch experiments were performed to study the chemical equilibrium state of the soil/solution system. Stirred flow-through reactor (SFTR) experiments were performed to study the kinetics and reversibility of sorption reactions at the surface of solid particles. Column experiments were also performed in saturated and unsaturated steady flow conditions. Experimental data pointed out a non-linear, instantaneous and reversible sorption process of Sr. A suitable cation-exchange model was used to describe the solute/soil reaction. The former model was coupled with transport models to describe behavior of Sr in saturated [2] and unsaturated flow conditions. Transport properties of sand packed columns have been determined with an inert tracer (HTO). BTCs obtained under saturated conditions exhibit a small amount of dispersion compared to those obtained under unsaturated conditions. Classical advection-dispersion model described successfully saturated tritium breakthrough curves (BTCs), whereas a mobile-immobile model (MIM) was required to described asymmetrical unsaturated BTCs. The MIM assumes that the porous medium contains a mobile water phase in which convective-dispersive transport occurs, and a immobile water phase with which solutes can exchange with a first order kinetic. In our experiments, transport by advection in the mobile phase is the predominant process whatever the flow conditions and mass transfer rate between the mobile and immobile regions is the predominant process for broadening the BTCs. Since dispersion is blurred by mass transfer resistance, the

  20. The Dependence of Water Permeability in Quartz Sand on Gas Hydrate Saturation in the Pore Space

    Science.gov (United States)

    Kossel, E.; Deusner, C.; Bigalke, N.; Haeckel, M.

    2018-02-01

    Transport of fluids in gas hydrate bearing sediments is largely defined by the reduction of the permeability due to gas hydrate crystals in the pore space. Although the exact knowledge of the permeability behavior as a function of gas hydrate saturation is of crucial importance, state-of-the-art simulation codes for gas production scenarios use theoretically derived permeability equations that are hardly backed by experimental data. The reason for the insufficient validation of the model equations is the difficulty to create gas hydrate bearing sediments that have undergone formation mechanisms equivalent to the natural process and that have well-defined gas hydrate saturations. We formed methane hydrates in quartz sand from a methane-saturated aqueous solution and used magnetic resonance imaging to obtain time-resolved, three-dimensional maps of the gas hydrate saturation distribution. These maps were fed into 3-D finite element method simulations of the water flow. In our simulations, we tested the five most well-known permeability equations. All of the suitable permeability equations include the term (1-SH)n, where SH is the gas hydrate saturation and n is a parameter that needs to be constrained. The most basic equation describing the permeability behavior of water flow through gas hydrate bearing sand is k = k0 (1-SH)n. In our experiments, n was determined to be 11.4 (±0.3). Results from this study can be directly applied to bulk flow analysis under the assumption of homogeneous gas hydrate saturation and can be further used to derive effective permeability models for heterogeneous gas hydrate distributions at different scales.

  1. Analysis of water and nitrogen use efficiency for maize (Zea mays L.) grown on soft rock and sand compound soil.

    Science.gov (United States)

    Wang, Huanyuan; Han, Jichang; Tong, Wei; Cheng, Jie; Zhang, Haiou

    2017-06-01

    Maize was grown on compound soils constituted from mixtures of soft rock and sand at different ratios, and water use efficiency (WUE), nitrogen use efficiency (NUE) and fertilizer nitrogen use efficiency (FNUE) were quantified. The data were used to assist in designing strategies for optimizing water and nitrogen management practices for maize on the substrates used. Maize was sown in composite soil prepared at three ratios of soft rock and sand (1:1, 1:2 and 1:5 v/v) in Mu Us Sandy Land, Yuyang district, Yulin city, China. Yields, amount of drainage, nitrogen (N) leaching, WUE and NUE were calculated. Then a water and nitrogen management model (WNMM) was calibrated and validated. No significant difference in evapotranspiration of maize was found among compound soils with soft rock/sand ratios of 1:1, 1:2 and 1:5, while water drainage increased significantly with increasing soft rock/sand ratio. WUE increased to 1.30 kg m -3 in compound soil with 1:2 soft rock/sand ratio. Nitrogen leaching and ammonia volatilization were the main reason for nitrogen loss, and N reduction mainly relied on crop uptake. NUE and FNUE could reach 33.1 and 24.9 kg kg -1 N respectively. Water drainage and nitrogen leaching occurred mostly during heavy rainfall or irrigation. Through a scenario analysis of different rainfall types, water and fertilizer management systems were formulated each year. This study shows that soft rock plays a key role in improving the WUE, NUE and FNUE of maize. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  2. 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.

  3. Investigations on organics in the Libyan beach sand and water: extraction, spectroscopy and gas chromatography, Zwarah to East Tripoli coastline

    International Nuclear Information System (INIS)

    Ali, L.H.; El-Jawashi, S.A.; Ejbali, A.A.; Garbaj, M.J.

    1998-01-01

    Forty-three samples from fifteen locations extending along 200 kilometers from near the Tunisian borders to 20 kilometers east of Tripoli harbour were examined for their organic contents. Sampling was conducted under the following specifications. 1. Dry beach sand, 3-4 meters away from water (denoted ds). 2. Wet beach sand, obtained from 1 meter depth (denoted ws). 3. Beach water (denoted w). Known amounts of sand (ds or ws) and beach water (w) were extracted with a suitable volume of chloroform. Organics in the extracts were determined gravimetrically by complete evaporation of chloroform, the residue was further examined by gas chromatography, and distribution of carbon numbers in each sample were assessed. Alternatively, a direct determination of organics concentration in CHCl 3 solution was obtained spectrophotometrically from calibration curves of absorptions at 410nm and 260nm. Infrared study on organics isolated from different locations enabled the assessment of the degree of oxidation suffered by each sample. This was obtained by comparing the relative absorption values at 1736 and 1712cm -1 , normalized with respect to 2925 cm -1 ; C-H stretching vibration; to rule out effects due to concentration. Organics concentration in shore water ranged from 0.05 to 9.50 ppm, depending on location and industrial activities, while much higher concentrations, ranging from 50-1500 ppm were detected in dry and wet beach sand samples. (author)

  4. Depth investigation of rapid sand filters for drinking water production reveals strong stratification in nitrification biokinetic behavior

    DEFF Research Database (Denmark)

    Tatari, Karolina; Smets, Barth F.; Albrechtsen, Hans-Jørgen

    2016-01-01

    The biokinetic behavior of NH4 + removal was investigated at different depths of a rapid sand filter treating groundwater for drinking water preparation. Filter materials from the top, middle and bottom layers of a full-scale filter were exposed to various controlled NH4 + loadings in a continuous...

  5. Removal of turbidity and suspended solids backwash water from rapid sand filter by using electrocoagulation

    Directory of Open Access Journals (Sweden)

    AR Yari

    2016-07-01

    Full Text Available Introduction: By appropriate method can be recycled more than 95 percent effluent backwashing the filter. This study aimed to examine the efficiency of the electrocoagulation process on turbidity and suspended solids removal from backwash effluent of rapid sand filter of water treatment plants No 1 in Karaj. Methods: This bench-scale experimental study was carried out on the samples of backwash effluent in a batch system. The Plexiglas tank with a volume of 4 liters, containing of 4 plate electrodes made of aluminum and iron was connected to a direct current power supply. Samples every 15 minutes to measure turbidity and suspended solids collected in the middle of the reactor and examined. Effect of several parameters such as current density, reaction time and voltage were studied. The total number of samples tested were 48. Turbidity and total suspended solids was measured by nephlometry and gravimetric method, respectively. Results: The highest removal efficiency of turbidity and suspended solids in reaction time of 60 minutes, current density of 2 mA and a voltage of 45 mV was observed. The highest removal efficiency of turbidity in aluminum and iron electrodes were 96.83 and 83.77 %, respectively. Also The highest removal efficiency of suspended solids were 96.73 and 86.22 %, respectively. Conclusion: The results showed that electro- coagulation process can be a good choice to remove turbidity and suspended from backwash of rapid sand filter. Aluminum electrode efficiency in the removal of turbidity and suspended solids was greater than the iron electrode.

  6. Impacts of oil sands process water on fen plants: Implications for plant selection in required reclamation projects

    International Nuclear Information System (INIS)

    Pouliot, Rémy; Rochefort, Line; Graf, Martha D.

    2012-01-01

    Fen plant growth in peat contaminated with groundwater discharges of oil sands process water (OSPW) was assessed in a greenhouse over two growing seasons. Three treatments (non-diluted OSPW, diluted OSPW and rainwater) were tested on five vascular plants and four mosses. All vascular plants tested can grow in salinity and naphthenic acids levels currently produced by oil sands activity in northwestern Canada. No stress sign was observed after both seasons. Because of plant characteristics, Carex species (C. atherodes and C. utriculata) and Triglochin maritima would be more useful for rapidly restoring vegetation and creating a new peat-accumulating system. Groundwater discharge of OSPW proved detrimental to mosses under dry conditions and ensuring adequate water levels would be crucial in fen creation following oil sands exploitation. Campylium stellatum would be the best choice to grow in contaminated areas and Bryum pseudotriquetrum might be interesting as it has spontaneously regenerated in all treatments. - Highlights: ► Fen plant growth was assessed under groundwater discharges of oil sands process water. ► Sedge and grass species were not stressed after two growing seasons in greenhouse. ► Carex species and Triglochin maritima would be helpful in created contaminated fens. ► In dry conditions, contaminated groundwater discharge was detrimental for mosses. ► Campylium stellatum would be the best choice in created fens with contaminated water. - Sedges and grasses tolerated the contact with oil sands process water and could probably grow well in contaminated created fens, but mosses were particularly affected under dry conditions.

  7. Application of a Low Cost Ceramic Filter for Recycling Sand Filter Backwash Water

    Directory of Open Access Journals (Sweden)

    Md Shafiquzzaman

    2018-02-01

    Full Text Available The aim of this study is to examine the application of a low cost ceramic filter for the treatment of sand filter backwash water (SFBW. The treatment process is comprised of pre-coagulation of SFBW with aluminum sulfate (Alum followed by continuous filtration usinga low cost ceramic filter at different trans-membrane pressures (TMPs. Jar test results showed that 20 mg/L of alum is the optimum dose for maximum removal of turbidity, Fe, and Mn from SFBW. The filter can be operated at a TMP between 0.6 and 3 kPa as well as a corresponding flux of 480–2000 L/m2/d without any flux declination. Significant removal, up to 99%, was observed forturbidity, iron (Fe, and manganese (Mn. The flux started to decline at 4.5 kPa TMP (corresponding flux 3280 L/m2/d, thus indicated fouling of the filter. The complete pore blocking model was found as the most appropriate model to explain the insight mechanism of flux decline. The optimum operating pressure and the permeate flux were found to be 3 kPa and 2000 L/m2/d, respectively. Treated SFBW by a low cost ceramic filter was found to be suitable to recycle back to the water treatment plant. The ceramic filtration process would be a low cost and efficient option to recycle the SFBW.

  8. Ground-Water Flow Direction, Water Quality, Recharge Sources, and Age, Great Sand Dunes National Monument, South-Central Colorado, 2000-2001

    Science.gov (United States)

    Rupert, Michael G.; Plummer, Niel

    2004-01-01

    Great Sand Dunes National Monument is located in south-central Colorado along the eastern edge of the San Luis Valley. The Great Sand Dunes National Monument contains the tallest sand dunes in North America; some rise up to750 feet. Important ecological features of the Great Sand Dunes National Monument are palustrine wetlands associated with interdunal ponds and depressions along the western edge of the dune field. The existence and natural maintenance of the dune field and the interdunal ponds are dependent on maintaining ground-water levels at historic elevations. To address these concerns, the U.S. Geological Survey conducted a study, in collaboration with the National Park Service, of ground-water flow direction, water quality, recharge sources, and age at the Great Sand Dunes National Monument. A shallow unconfined aquifer and a deeper confined aquifer are the two principal aquifers at the Great Sand Dunes National Monument. Ground water in the unconfined aquifer is recharged from Medano and Sand Creeks near the Sangre de Cristo Mountain front, flows underneath the main dune field, and discharges to Big and Little Spring Creeks. The percentage of calcium in ground water in the unconfined aquifer decreases and the percentage of sodium increases because of ionic exchange with clay minerals as the ground water flows underneath the dune field. It takes more than 60 years for the ground water to flow from Medano and Sand Creeks to Big and Little Spring Creeks. During this time, ground water in the upper part of the unconfined aquifer is recharged by numerous precipitation events. Evaporation of precipitation during recharge prior to reaching the water table causes enrichment in deuterium (2H) and oxygen-18 (18O) relative to waters that are not evaporated. This recharge from precipitation events causes the apparent ages determined using chlorofluorocarbons and tritium to become younger, because relatively young precipitation water is mixing with older waters

  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. Study on of Seepage Flow Velocity in Sand Layer Profile as Affected by Water Depth and Slope Gradience

    Science.gov (United States)

    Han, Z.; Chen, X.

    2017-12-01

    BACKGROUND: The subsurface water flow velocity is of great significance in understanding the hydrodynamic characteristics of soil seepage and the influence of interaction between seepage flow and surface runoff on the soil erosion and sediment transport process. OBJECTIVE: To propose a visualized method and equipment for determining the seepage flow velocity and measuring the actual flow velocity and Darcy velocity as well as the relationship between them.METHOD: A transparent organic glass tank is used as the test soil tank, the white river sand is used as the seepage test material and the fluorescent dye is used as the indicator for tracing water flow, so as to determine the thickness and velocity of water flow in a visualized way. Water is supplied at the same flow rate (0.84 L h-1) to the three parts with an interval of 1m at the bottom of the soil tank and the pore water velocity and the thickness of each water layer are determined under four gradient conditions. The Darcy velocity of each layer is calculated according to the water supply flow and the discharge section area. The effective discharge flow pore is estimated according to the moisture content and porosity and then the relationship between Darcy velocity and the measured velocity is calculated based on the water supply flow and the water layer thickness, and finally the correctness of the calculation results is verified. RESULTS: According to the velocity calculation results, Darcy velocity increases significantly with the increase of gradient; in the sand layer profile, the flow velocity of pore water at different depths increases with the increase of gradient; under the condition of the same gradient, the lower sand layer has the maximum flow velocity of pore water. The air-filled porosity of sand layer determines the proportional relationship between Darcy velocity and pore flow velocity. CONCLUSIONS: The actual flow velocity and Darcy velocity can be measured by a visualized method and the

  11. Optimizing nitrification in biological rapid sand filters for drinking water production

    DEFF Research Database (Denmark)

    Albrechtsen, Hans-Jørgen; Smets, Barth F.; Lee, Carson Odell

    Addition of phosphate or trace metals or better management e.g. in terms of anmonium load can improve the nitrification rate and efficiency in biological rapid sand filters.......Addition of phosphate or trace metals or better management e.g. in terms of anmonium load can improve the nitrification rate and efficiency in biological rapid sand filters....

  12. Azimuthal Structure of the Sand Erg that Encircles the North Polar Water-Ice Cap

    Science.gov (United States)

    Teodoro, L. A.; Elphic, R. C.; Eke, V. R.; Feldman, W. C.; Maurice, S.; Pathare, A.

    2011-12-01

    The sand erg that completely encircles the perennial water-ice cap that covers the Martian north geographic pole displays considerable azimuthal structure as seen in visible and near-IR images. Much of this structure is associated with the terminations of the many steep troughs that cut spiral the approximately 3 km thick polar ice cap. Other contributions come from the katabatic winds that spill over steep-sided edges of the cap, such as what bounds the largest set of dunes that comprise Olympia Undae. During the spring and summer months when these winds initiate from the higher altitudes that contain sublimating CO2 ice, which is very cold and dry, heat adiabatically when they compress as they lose altitude. These winds should then remove H2O moisture from the uppermost layer of the sand dunes that are directly in their path. Two likely locations where this desiccation may occur preferentially is at the termination of Chasma Boreale and the ice cap at Olympia Undae. We will search for this effect by sharpening the spatial structure of the epithermal neutron counting rates measured at northern high latitudes using the Mars Odyssey Neutron Spectrometer (MONS). The epithermal range of neutron energies is nearly uniquely sensitive to the hydrogen content of surface soils, which should likely be in the form of H2O/OH molecules/radicals. We therefore convert epithermal counting rates in terms of Water-Equivalent-Hydrogen, WEH. However, MONS counting-rate data have a FWHM of ~550 km., which is sufficiently broad to prevent a close association of WEH variability with images of geological features. In this study, we reduce spurious features in the instrument smeared neutron counting rates through deconvolution. We choose the PIXON numerical deconvolution technique for this purpose. This technique uses a statistical approach (Pina 2001, Eke 2001), which is capable of removing spurious features in the data in the presence of noise. We have previously carried out a detailed

  13. Water uptake and stress development in bentonites and bentonite-sand buffer materials

    International Nuclear Information System (INIS)

    Dixon, D.A.; Wan, A.W-L.; Gray, M.N.; Miller, S.H.

    1996-10-01

    The development of swelling pressure and the transfer of pore water pressures through dense bentonite and bentonite-sand materials are examined in this report. This report focuses on the swelling pressure and total pressure developed in initially unsaturated specimens allowed access to free water on one end. The bentonite in this wetted region rapidly develops its full swelling pressure and this pressure is transferred upwards through the specimen. Hence, the bentonite plug will exert a pressure approximately equivalent to the swelling pressure even though only a small region of the plug is actually saturated. A number of specimens were tested with total pressure sensors mounted normal and parallel to the axis of compaction. Lateral pressures developed long before the wetting front reached sensor locations, suggesting stress transfer through the unsaturated portions of these specimens. On achieving saturation, specimens were found to have similar swelling pressures both normal to and parallel to the axis of compaction. This indicates that there is little or no specimen anisotropy induced by the compaction process. Tests were conducted on specimens allowed only to take on a limited quantity of water and it was found that density anisotropy was induced as the result of the swelling pressures generated by the buffer. The wetted skin of buffer developed a considerable pressure and compressed a region of buffer immediately above the wetted region. The results suggest that the buffer material placed in a disposal vault will rapidly develop and transfer swelling pressures as a result of the saturation of a limited region or 'skin' within the emplacement site. The total pressure ultimately present on the container surface should be the sum of the swelling and hydraulic components. (author). 14 refs., 4 tabs., 8 figs

  14. 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.

  15. Investigation of Water Holding Capacity of Sugarcane Mulch for Sand Dune Stabilization in Ahvaz

    Directory of Open Access Journals (Sweden)

    T. Jamili

    2017-01-01

    Full Text Available Introduction: Wind erosion is one of the most serious problems in southwest Iran. Fine-grained structure of sand dunes with not enough strong composition and their low moisture retention property make them susceptible to wind erosion. They lack organic matter and are considered inherently of low fertility (Ahmadi, 2002. Studies have shown that non-erodible materials which include bentonite clay (Diouf et al., 1990, ureamelamine formaldehyde and urea–formaldehyde with 0.25% sodium chloride (Lahalih and Ahmed, 1998, acids, enzymes, lignosulfonates, polymers, tree resins (Santoni et al., 2001, waterborne polymer emulsion (Al-Khanbashi and Abdalla, 2006, polyvinyl alcohol and a polyvinyl acetate emulsion (Newman et al., 2005; Han et al., 2007, ash and polyacrylamide (Yang and Zejun, 2012.have significant potential in reducing wind erosion The area under farming of sugarcane in Khuzestan, Iran, is more than 130,000, ha. Vinasse and Filter Kike are two organic ingredients of sugarcane residues which are generated as byproduct materials insugarcane processing. In recent years these residues have been released into the environment and cause it regarded as water pollutant. Over 800,000 m3 of Vinasse is annually stored in each agro-industry. Vinasse also is rich in K, Ca, and Mg with moderate amounts of P and N,and non toxic complexes or heavy metals. Filter Kike is another residue produced in huge amounts by the agro-industry that is composed of cellulosic substances, CaCO3, N, P, K, organic matter, and clay. Therefore, the objective of this research is to investigate the effect of sugarcane mulch on water holding capacity in soil. This study is performed to evaluate the feasibility of using sugarcane residues inproduce of ecofriendly mulches for environmental use. In order of achieving these goals, Vinase, Filter Cake, and clay soil from near the sand dunes were used as sugarcane mulches. Further comparison between traditional oil mulches and

  16. 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.

  17. Total and methyl mercury concentrations in sediment and water of a constructed wetland in the Athabasca Oil Sands Region

    International Nuclear Information System (INIS)

    Oswald, Claire J.; Carey, Sean K.

    2016-01-01

    In the Athabasca Oil Sands Region in northeastern Alberta, Canada, oil sands operators are testing the feasibility of peatland construction on the post-mining landscape. In 2009, Syncrude Canada Ltd. began construction of the 52 ha Sandhill Fen pilot watershed, including a 15 ha, hydrologically managed fen peatland built on sand-capped soft oil sands tailings. An integral component of fen reclamation is post-construction monitoring of water quality, including salinity, fluvial carbon, and priority pollutant elements. In this study, the effects of fen reclamation and elevated sulfate levels on mercury (Hg) fate and transport in the constructed system were assessed. Total mercury (THg) and methylmercury (MeHg) concentrations in the fen sediment were lower than in two nearby natural fens, which may be due to the higher mineral content of the Sandhill Fen peat mix and/or a loss of Hg through evasion during the peat harvesting, stockpiling and placement processes. Porewater MeHg concentrations in the Sandhill Fen typically did not exceed 1.0 ng L −1 . The low MeHg concentrations may be a result of elevated porewater sulfate concentrations (mean 346 mg L −1 ) and an increase in sulphide concentrations with depth in the peat, which are known to suppress MeHg production. Total Hg and MeHg concentrations increased during a controlled mid-summer flooding event where the water table rose above the ground surface in most of the fen. The Hg dynamics during this event showed that hydrologic fluctuations in this system exacerbate the release of THg and MeHg downstream. In addition, the elevated SO 4 2− concentrations in the peat porewaters may become a problem with respect to downstream MeHg production once the fen is hydrologically connected to a larger wetland network that is currently being constructed. - Highlights: • A constructed fen peatland in the Athabasca Oil Sands Region was studied. • Total and methyl mercury concentrations in fen sediment and waters

  18. Effects of solar collecting area and water flow rate on the performance of a sand bed solar collector

    International Nuclear Information System (INIS)

    Maganhar, A.L.; Memon, A.H.; Panhwar, M.I.

    2005-01-01

    The often discussed renewable sources of energy have been great interest to energy researchers and planners for quite some time. The primary of renewing all sources of energy is the sun. There have been two main problems not yet fully resolved. One is the large scale production of energy and other is the cost factor. In the present study, the cost factor is under consideration. In this regard a non-conventional solar collector using indigenous material (pit sand) as solar absorber is designed and manufactured. This paper presents the results of an investigation of the effect of solar collecting area and water flow rate on the performance of a pit sand bed solar collector especially in terms of rise in water temperature. Three pit sand solar collectors of area 1m/sup 2/ each were connected in series to enhance the collecting area and the system was tested for different flow rates. Experimental results proved that there was increase in water temperature with increase in solar collecting area an decreases in water temperature with increase in flow rate. (author)

  19. 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.

  20. A breakthrough low energy desalination process : production of sustainable water from brackish water for the oil sands industry

    Energy Technology Data Exchange (ETDEWEB)

    Man, M.; Sparrow, B.; Zoshi, J. [Saltwork Technologies Inc., BC (Canada)

    2010-07-01

    This paper described an innovative desalination system pilot study that is currently being conducted in Vancouver, British Columbia (BC). The thermo-ionic proof-tested system has the potential to achieve an electrical energy consumption rate of less than 1 kW per m{sup 3} through the harnessing of low grade heat. The energy transfer is accomplished by manipulating concentration gradients established and maintained through the evaporation of salt water into the atmosphere. The ion exchange mechanism reduced pre-treatment requirements and provided a self-cleaning mechanism to maintain steady production levels. The electrical energy created during the process was used to run low-pressure circulation pumps and process controls. The driving force for evaporation was the vapor pressure difference between the solution and moisture in the air. Discharges from the system can be tuned to various salt water concentrations. Results of the pilot study to date indicate that it is suitable for use in oil sands steam assisted gravity drainage (SAGD) processes. 8 refs., 1 tab., 4 figs.

  1. The Effect of Water Cement Ratio on Cement Brick Containing High Density Polyethylene (HDPE as Sand Replacement

    Directory of Open Access Journals (Sweden)

    Ali Noorwirdawati

    2018-01-01

    Full Text Available Waste disposal can contribute to the problem of environmental pollution. Most of the waste material is plastic based, because the nature of difficult of plastic degradable by itself. In order to overcome the problem, many study has been conducted on the reuse of plastic material into various field such as civil engineering and construction. In this study, municipal solid waste (MSW in the form of High Density Polyethylene (HDPE plastic was used to replace sand in cement sand brick production. The HDPE used in this study was obtained from a recycle factory at Nilai, Negeri Sembilan. 3% of HDPE replacement was applied in this study, with the cement-sand mix design of 1:6 and water-cement ratio 0.35, 0.40, 0.45 and 0.50 respectively. All specimens were tested for compressive strength and water absorption at 7 and 28 days. The density of the bricks was also recorded. The finding show that brick with 3% HDPE content and 0.45 of water-cement ratio at 28 days of age curing show the highest compressive strength, which is 19.5N/mm2 compared to the control specimen of 14.4 N/mm2.

  2. Arsenic Removal from Drinking Water by Absorptive Media-U.S. EPA Demonstration Project at Desert Sands MDWCA, NM Final Performance Evaluation Report

    Science.gov (United States)

    This report documents the activities performed and the results obtained for the arsenic removal treatment technology demonstration project at the Desert Sands Mutual Domestic Water Consumers Association (MDWCA) facility in Anthony, NM. The objectives of the project were to evalu...

  3. A Numerical Investigation on the Effect of Gas Pressure on the Water Saturation of Compacted Bentonite-Sand Samples

    Directory of Open Access Journals (Sweden)

    Jiang-Feng Liu

    2017-01-01

    Full Text Available In deep geological disposal for high-level radioactive waste, the generated gas can potentially affect the sealing ability of bentonite buffers. There is a competition between water and gas: the former provides sealing by swelling bentonite, and the latter attempts to desaturate the bentonite buffer. Thus, this study focused on numerically modelling the coupling effects of water and gas on the water saturation and sealing efficiency of compacted bentonite-sand samples. Different gas pressures were applied to the top surface of an upper sample, whereas the water pressure on the bottom side of the lower sample was maintained at 4 MPa. The results indicated that gas pressure did not significantly affect the saturation of the bentonite-sand sample until 2 MPa. At 2 MPa, the degree of water saturation of the upper sample was close to 1.0. As the gas pressure increased, this influence was more apparent. When the gas pressure was 6 MPa or higher, it was difficult for the upper sample to become fully saturated. Additionally, the lower sample was desaturated due to the high gas pressure. This indicated that gas pressure played an important role in the water saturation process and can affect the sealing efficiency of bentonite-based buffer materials.

  4. Ground-water quality in agricultural areas, Anoka Sand Plain Aquifer, east-central Minnesota, 1984-90

    Science.gov (United States)

    Landon, M.K.; Delin, G.N.

    1995-01-01

    Ground-water quality in the Anoka Sand Plain aquifer was studied as part of the multiscale Management Systems Evaluation Area (MSEA) study by collecting water samples from shallow wells during August through November 1990. The sampling was conducted to: (1) aid in selection of the MSEA research area; (2) facilitate comparison of results at the MSEA research area to the regional scale; and (3) evaluate changes in ground-water quality in the Anoka Sand Plain aquifer since a previous study during 1984 through 1987. Samples were collected from 34 wells screened in the upper 6 meters of the surficial aquifer and located in cultivated agricultural areas. Water temperature, pH, specific conductance, and presence or absence of triazine herbicides were determined at all sites and samples from selected wells were analyzed for concentrations of dissolved oxygen, alkalinity, major cations and anions, nutrients, and selected herbicides and herbicide metabolites. The results of the study indicate that the water-quality of some shallow ground water in areas of predominantly agricultural land use has been affected by applications of nitrogen fertilizers and the herbicide atrazine.

  5. Investigation of Dynamic Properties of Water-Saturated Sand by the Results of the Inverse Experiment Technique

    Science.gov (United States)

    Bragov, A. M.; Balandin, Vl. V.; Kotov, V. L.; Balandin, Vl. Vl.

    2018-04-01

    We present new experimental results on the investigation of the dynamic properties of sand soil on the basis of the inverse experiment technique using a measuring rod with a flat front-end face. A limited applicability has been shown of the method using the procedure for correcting the shape of the deformation pulse due to dispersion during its propagation in the measuring rod. Estimates of the pulse maximum have been obtained and the results of comparison of numerical calculations with experimental data are given. The sufficient accuracy in determining the drag force during the quasi-stationary stage of penetration has been established. The parameters of dynamic compressibility and resistance to shear of water-saturated sand have been determined in the course of the experimental-theoretical analysis of the maximum values of the drag force and its values at the quasi-stationary stage of penetration. It has been shown that with almost complete water saturation of sand its shear properties are reduced but remain significant in the practically important range of penetration rates.

  6. Modelling the removal of p-TSA (para-toluenesulfonamide) during rapid sand filtration used for drinking water treatment.

    Science.gov (United States)

    Meffe, Raffaella; Kohfahl, Claus; Holzbecher, Ekkehard; Massmann, Gudrun; Richter, Doreen; Dünnbier, Uwe; Pekdeger, Asaf

    2010-01-01

    A finite element model was set-up to determine degradation rate constants for p-TSA during rapid sand filtration (RSF). Data used for the model originated from a column experiment carried out in the filter hall of a drinking water treatment plant in Berlin (Germany). Aerated abstracted groundwater was passed through a 1.6m long column-shaped experimental sand filter applying infiltration rates from 2 to 6mh(-1). Model results were fitted to measured profiles and breakthrough curves of p-TSA for different infiltration rates using both first-order reaction kinetics and Michaelis-Menten kinetics. Both approaches showed that degradation rates varied both in space and time. Higher degradation rates were observed in the upper part of the column, probably related to higher microbial activity in this zone. Measured and simulated breakthrough curves revealed an adaption phase with lower degradation rates after infiltration rates were changed, followed by an adapted phase with more elevated degradation rates. Irrespective of the mathematical approach and the infiltration rate, degradation rates were very high, probably owing to the fact that filter sands have been in operation for decades, receiving high p-TSA concentrations with the raw water.

  7. Radium desorption, manganese and iron dissolution from sand filters of a conventional ground water treatment plant under reductive conditions

    International Nuclear Information System (INIS)

    Al-Hobaib, A.S.; Al-Sulaiman, K.M.; Al-Dhayan, D.M.; Al-Suhybani, A.A.

    2006-01-01

    Sand filters are used as a filter bed in many ground water treatment plants to remove the physical contaminants and oxidation products. A build-up of radioactivity may take place on the granules, where iron and manganese oxides are deposited and form thin films on the surface of sand filter. The oxides of iron and manganese play an important role in adsorbing radium from ground water. The disposal of those granules makes a significant problem. A batch technique is used for solubilization of radium from sand filters in the presence of some organic acids, which act as reducing agents. These acids are formic acid, acetic acid, benzoic acid, succinic acid, oxalic acid, phthalic acid, and adipic acid. The data were obtained as a function of acidity, temperature, contact time and liquid/solid ratio particle size and shaking speed. It was found that oxalic acid was the best for radium removal. The effectiveness of these acids on radium removal was as follows: oxalic acid > phthalic acid > adipic acid > succinic acid > formic acid > acetic acid. The maximum removal obtained was 69.9% at 1M oxalic acid at 8 ml/g ratio. Reaction kinetics and mechanism parameters of the dissolution process were studied and compared with other published data. (author)

  8. Water/sand flooded and immersed critical experiment and analysis performed in support of the TOPAZ-II Safety Program

    International Nuclear Information System (INIS)

    Glushkov, E.S.; Ponomarev-Stepnoi, N.N.; Bubelev, V.G.; Garin, V.P.; Gomin, E.A.; Kompanietz, G.V.; Krutoy, A.M.; Lobynstev, V.A.; Maiorov, L.V.; Polyakov, D.N.

    1994-01-01

    Presented is a brief description of the Narciss-M2 critical assemblies, which simulate accidental water/wet-sand immersion of the TOPAZ-II reactor as well as water-flooding of core cavities. Experimental results obtained from these critical assemblies, including experiments with several fuel elements removed from the core, are shown. These configurations with several extracted fuel elements simulate a proposed fuel-out anticriticality-device modification to the TOPAZ-II reactor. Preliminary computational analysis of these experiments using the Monte Carlo neutron-transport method is outlined. Nuclear criticality safety of the TOPAZ-II reactor with an incorporated anticriticality unit is demonstrated

  9. Total and methyl mercury concentrations in sediment and water of a constructed wetland in the Athabasca Oil Sands Region.

    Science.gov (United States)

    Oswald, Claire J; Carey, Sean K

    2016-06-01

    In the Athabasca Oil Sands Region in northeastern Alberta, Canada, oil sands operators are testing the feasibility of peatland construction on the post-mining landscape. In 2009, Syncrude Canada Ltd. began construction of the 52 ha Sandhill Fen pilot watershed, including a 15 ha, hydrologically managed fen peatland built on sand-capped soft oil sands tailings. An integral component of fen reclamation is post-construction monitoring of water quality, including salinity, fluvial carbon, and priority pollutant elements. In this study, the effects of fen reclamation and elevated sulfate levels on mercury (Hg) fate and transport in the constructed system were assessed. Total mercury (THg) and methylmercury (MeHg) concentrations in the fen sediment were lower than in two nearby natural fens, which may be due to the higher mineral content of the Sandhill Fen peat mix and/or a loss of Hg through evasion during the peat harvesting, stockpiling and placement processes. Porewater MeHg concentrations in the Sandhill Fen typically did not exceed 1.0 ng L(-1). The low MeHg concentrations may be a result of elevated porewater sulfate concentrations (mean 346 mg L(-1)) and an increase in sulphide concentrations with depth in the peat, which are known to suppress MeHg production. Total Hg and MeHg concentrations increased during a controlled mid-summer flooding event where the water table rose above the ground surface in most of the fen. The Hg dynamics during this event showed that hydrologic fluctuations in this system exacerbate the release of THg and MeHg downstream. In addition, the elevated SO4(2-) concentrations in the peat porewaters may become a problem with respect to downstream MeHg production once the fen is hydrologically connected to a larger wetland network that is currently being constructed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Bed topography and sand transport responses to a step change in discharge and water depth

    Science.gov (United States)

    Ephemeral streams with sand and gravel beds may inherit bed topography caused by previous flow events, resulting in bed topography that is not in equilibrium with flow conditions, complicating the modeling of flow and sediment transport. Major flow events, resulting from rainfall with high intensity...

  11. Rice straw biochar affects water retention and air movement in a sand-textured tropical soil

    DEFF Research Database (Denmark)

    Arthur, Emmanuel; Ahmed, Fauziatu

    2017-01-01

    Despite the current global attention on biochar (BC) as a soil amendment, knowledge is limited on how BC impacts the physical properties of coarse-textured soils (sand > 95%), particularly in tropical regions. A two-season field-study was conducted to investigate the effect of rice straw BC (3% w...

  12. The effects of season and sand mining activities on thermal regime and water quality in a large shallow tropical lake.

    Science.gov (United States)

    Sharip, Zati; Zaki, Ahmad Taqiyuddin Ahmad

    2014-08-01

    Thermal structure and water quality in a large and shallow lake in Malaysia were studied between January 2012 and June 2013 in order to understand variations in relation to water level fluctuations and in-stream mining activities. Environmental variables, namely temperature, turbidity, dissolved oxygen, pH, electrical conductivity, chlorophyll-A and transparency, were measured using a multi-parameter probe and a Secchi disk. Measurements of environmental variables were performed at 0.1 m intervals from the surface to the bottom of the lake during the dry and wet seasons. High water level and strong solar radiation increased temperature stratification. River discharges during the wet season, and unsustainable sand mining activities led to an increased turbidity exceeding 100 NTU, and reduced transparency, which changed the temperature variation and subsequently altered the water quality pattern.

  13. Development of water quality objectives and management systems for the lower Athabasca River in the oil sands area

    International Nuclear Information System (INIS)

    Noton, L.; McEachern, P.

    2004-01-01

    This paper addressed environmental concerns related to the increased oil sands activity along the lower Athabasca River in northeastern Alberta. The concerns include potential effects on water quality of the river even though wastewaters do not currently reach the Athabasca River, nor do they have any significant effects. However, as the industry expands, there is concern that releases of wastewater may increase significantly. A multi-stakeholder group called the Cumulative Environmental Management Association (CEMA) has addressed some of these environmental management issues in the Athabasca area by establishing a water quality task group that examines water quality protection and management activities. The task group intends to develop and recommend water quality objectives and management options on the lower Athabasca River. Their 4 part process includes: (1) defining the problem, (2) setting goals, (3) measuring performance, and (4) managing and adapting to potential impacts. The group has identified and defined about 35 water quality variables of potential concern. It has also identified the uses of water it wants to protect and intends to prevent the degradation of water quality. A plan for developing site specific water quality objectives has been established following a review of water quality guidelines. Performance will be measured using water quality models that simulate full development scenarios. The modelling work will be instrumental in designing management schemes for any potential impacts

  14. Integrated metagenomic and physiochemical analyses to evaluate the potential role of microbes in the sand filter of a drinking water treatment system.

    Directory of Open Access Journals (Sweden)

    Yaohui Bai

    Full Text Available While sand filters are widely used to treat drinking water, the role of sand filter associated microorganisms in water purification has not been extensively studied. In the current investigation, we integrated molecular (based on metagenomic and physicochemical analyses to elucidate microbial community composition and function in a common sand filter used to treat groundwater for potable consumption. The results revealed that the biofilm developed rapidly within 2 days (reaching ≈ 10(11 prokaryotes per gram in the sand filter along with abiotic and biotic particulates accumulated in the interstitial spaces. Bacteria (up to 90% dominated the biofilm microbial community, with Alphaproteobacteria being the most common class. Thaumarchaeota was the sole phylum of Archaea, which might be involved in ammonia oxidation. Function annotation of metagenomic datasets revealed a number of aromatic degradation pathway genes, such as aromatic oxygenase and dehydrogenase genes, in the biofilm, suggesting a significant role for microbes in the breakdown of aromatic compounds in groundwater. Simultaneous nitrification and denitrification pathways were confirmed as the primary routes of nitrogen removal. Dissolved heavy metals in groundwater, e.g. Mn(2+ and As(3+, might be biologically oxidized to insoluble or easily adsorbed compounds and deposited in the sand filter. Our study demonstrated that the role of the microbial community in the sand filter treatment system are critical to effective water purification in drinking water.

  15. Integrated metagenomic and physiochemical analyses to evaluate the potential role of microbes in the sand filter of a drinking water treatment system.

    Science.gov (United States)

    Bai, Yaohui; Liu, Ruiping; Liang, Jinsong; Qu, Jiuhui

    2013-01-01

    While sand filters are widely used to treat drinking water, the role of sand filter associated microorganisms in water purification has not been extensively studied. In the current investigation, we integrated molecular (based on metagenomic) and physicochemical analyses to elucidate microbial community composition and function in a common sand filter used to treat groundwater for potable consumption. The results revealed that the biofilm developed rapidly within 2 days (reaching ≈ 10(11) prokaryotes per gram) in the sand filter along with abiotic and biotic particulates accumulated in the interstitial spaces. Bacteria (up to 90%) dominated the biofilm microbial community, with Alphaproteobacteria being the most common class. Thaumarchaeota was the sole phylum of Archaea, which might be involved in ammonia oxidation. Function annotation of metagenomic datasets revealed a number of aromatic degradation pathway genes, such as aromatic oxygenase and dehydrogenase genes, in the biofilm, suggesting a significant role for microbes in the breakdown of aromatic compounds in groundwater. Simultaneous nitrification and denitrification pathways were confirmed as the primary routes of nitrogen removal. Dissolved heavy metals in groundwater, e.g. Mn(2+) and As(3+), might be biologically oxidized to insoluble or easily adsorbed compounds and deposited in the sand filter. Our study demonstrated that the role of the microbial community in the sand filter treatment system are critical to effective water purification in drinking water.

  16. Density and distribution of nitrifying guilds in rapid sand filters for drinking water production: Dominance of Nitrospira spp

    DEFF Research Database (Denmark)

    Tatari, Karolina; Musovic, Sanin; Gülay, Arda

    2017-01-01

    distribution of these guilds, filter material was sampled at four drinking water treatment plants (DWTPs) in parallel filters of the pre- and after-filtration stages at different locations and depths. The target guilds were quantified by qPCR targeting 16S rRNA and amoA genes. Total bacterial densities......We investigated the density and distribution of total bacteria, canonical Ammonia Oxidizing Bacteria (AOB) (Nitrosomonas plus Nitrosospira), Ammonia Oxidizing Archaea (AOA), as well as Nitrobacter and Nitrospira in rapid sand filters used for groundwater treatment. To investigate the spatial...

  17. Amplitude equation for under water sand-ripples in one dimension

    DEFF Research Database (Denmark)

    observed when the amplitude $d$ is suddenly varied. The equation has the form h_t=- ε(h-mean(h))+((h_x)^2-1)h_(xx)- h_(xxxx)+ δ((h_x)^2)_(xx) which, due to the first term, is neither completely local (it has long-range coupling through the average height mean(h)) nor has local sand conservation. We argue...

  18. 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....

  19. Tritium profiles in Kalahari sands as a measure of rain water recharge

    International Nuclear Information System (INIS)

    Verhagen, B.T.; Smith, P.E.; McGeorge, I.; Dziembowski, Z.

    1978-01-01

    This paper attempts to relate recharge measurements in the Kalahari by tritium profiles in the unsaturated zone to isotopic, hydrochemical and hydrologic data from an underlying, semi-confined aquifer. Auger holes into the sand cover were drilled along a line of experimental deeper holes penetrating the saturated zone. A further line of auger holes was drilled into the dune sand cover of a control area. Variable moisture contents, apparently indepent of grain size distribution and indicating transients are observed in the different profiles. 3 H and 18 O measurements on the moisture contents allow for the identification of the 1962/63 bomb tritium rise and successive drier and wetter periods. Infiltration, or potential recharge as percentage of infiltration was found to be strongly dependent on the annual rainfall. The distribution of 14 C, 13 C, 3 H and chemistry in the shallower of two underlying aquifers leads to the consideration of three possible mechanisms of recharge. Arguments favouring vertical recharge are presented, which lead to possible extrapolations into the sand covered areas of the Kalahari in general. (orig.) [de

  20. 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

  1. Rapid increases in permeability and porosity of bentonite-sand mixtures due to alteration by water vapor

    International Nuclear Information System (INIS)

    Couture, R.A.

    1984-01-01

    Packed columns of canister packing material containing 25% bentonite and 75% quartz or basalt sand, were exposed to water vapor at temperatures up t 260 0 C. The permeabilities of the columns were subsequently measured after complete saturation with liquid water in a pressurized system. Exposure to water vapor caused irreversible increases in permeability by factors of up to 10 5 . After saturation with liquid water, the permeability was nearly independent of temperature. The increases in permeability were due to a large decrease in the ability of the bentonite to swell in water. Calculations suggest that swelling of bentonite altered at 250 0 C was not sufficient to fill the pore spaces. If the pore spaces are filled, the mixture will form an effective barrier against flow, diffusion, and transport of colloids. The results suggest that if bentonite-based canister packing material is exposed even briefly to water vapor at high temperatures in a high-level nuclear waste repository, its performance will be seriously impaired. The problem is less severe if the proportion of bentonite is high and the material is highly compacted. Previous results show significant degradation of bentonite by water vapor at temperatures as low as 150 0 C. This suggests that in some repositories, backfill in tunnels and drifts may also be affected. 9 references, 5 figures, 1 table

  2. Water/sand flooded and immersed critical experiment and analysis performed in support of the TOPAZ-II safety program

    International Nuclear Information System (INIS)

    Glushkov, E.S.; Ponomarev-Stepnoi, N.N.; Bubelev, V.G.; Garin, V.P.; Gomin, E.A.; Kompanietz, G.V.; Krutov, A.M.; Lobynstev, V.A.; Maiorov, L.V.; Polyakov, D.N.; Chunyaev, E.I.; Marshall, A.C.; Sapir, J.L.; Pelowitz, D.B.

    1995-01-01

    Presented is a brief description of the Narciss-M2 critical assemblies, which simulate accidental water/wet-sand immersion of the TOPAZ-II reactor as well as water-flooding of core cavities. Experimental results obtained from these critical assemblies, including experiments with several fuel elements removed from the core, are shown. These configurations with several extracted fuel elements simulate a proposed fuel-out anticriticality-device modification to the TOPAZ-II reactor. Preliminary computational analysis of these experiments using the Monte Carlo neutron-transport method is outlined. Nuclear criticality safety of the TOPAZ-II reactor with an incorporated anticriticality unit is demonstrated. copyright 1995 American Institute of Physics

  3. Monitoring and ming bio-physical parameters for hypoxia hazard in a coastal sand pit

    DEFF Research Database (Denmark)

    Mariani, Patrizio; Benassai, Guido; Grieco, Luisa

    2018-01-01

    Management of coastal areas requires monitoring and modeling of the anthropogenic drivers and the bio-physical processes affecting water quality. To assess the range of hydrographic conditions controlling oxygen distribution in the bottom layers of sand pits, a multi-year oceanographic survey has...... of the sand pits is associated with higher temperatures and wind speed lower than 5 m/s, which is not infrequent during the summer season. However, the number of consecutive days of oxygen depletion can be considered lower than the danger threshold level assumed in the literature....

  4. Surface and groundwater management in the oil sands industry

    International Nuclear Information System (INIS)

    Dixon, D.G.; Barker, J.

    2004-02-01

    A study was conducted to examine the sublethal effects of oil sands constituents on gill and liver histopathology and fish reproduction. Field studies of food web dynamics were conducted using stable isotopes, including oil sands constituents degradation isotope studies. The objective was to determine changes in food web dynamics associated with reclamation methods and maturity using stable isotopes. The study related changes in toxicity to changes in ground and surface naphthenic acids concentration and composition. It also demonstrated the natural attenuation of toxic chemicals as they travel through groundwater to potential surface water receptors. A methodology was developed to assess the natural attenuation capacity for future situations involving process-affected groundwater of different chemistry with different critical potential contaminants such as sulphides, metals, and specific organics. The mobility and natural attenuation of process water chemicals migrating in groundwater was also assessed. tabs., figs

  5. River modeling and multi-level fish health assessment to evaluate impacts from oil sands water releases (Part 2)

    International Nuclear Information System (INIS)

    Shaw, R.; Swanson, S.M.; Lagimodiere, M.; Gulley, J.

    1995-01-01

    A multi-level, multi-scale approach was used to assess potential impacts to fish health from oil sands water releases. The method used to arrive at predicted impacts involved assembling experimental data on the effects of chronic exposure to oil sands wastewaters on biochemical, physiological and whole-organism endpoint. This information was used to determine no effect levels (NOELs) and lowest effect levels (LOELs) for the suite of fish health parameters used in laboratory experiments (primarily biochemical and physiological measurement endpoints). LOELs and NOELs were compared to modeled concentrations of wastewater in the Athabasca River for five time snapshots. For each time period, concentrations were predicted based on mean annual flows and 7Q10 flows (low flows). This comparison was used to predict impacts on biochemical/physiological endpoints. Impacts on at the whole-organism and population-level were determined by comparing what the laboratory data would predict with what was observed in the field. This process was used to draw a conclusion regarding the health and sustainability of fish populations

  6. Reducing phosphorus loading of surface water using iron-coated sand

    NARCIS (Netherlands)

    Groenenberg, J.E.; Chardon, W.J.; Koopmans, G.F.

    2013-01-01

    Phosphorus losses from agricultural soils is an important source of P in surface waters leading to surface water quality impairment. In addition to reducing P inputs, mitigation measures are needed to reduce P enrichment of surface waters. Because drainage of agricultural land by pipe drainage is an

  7. Suitability assessment of grey water quality treated with an upflow-downflow siliceous sand/marble waste filtration system for agricultural and industrial purposes.

    Science.gov (United States)

    Chaabane, Safa; Riahi, Khalifa; Hamrouni, Hédi; Thayer, Béchir Ben

    2017-04-01

    The present study examines the suitability assessment of an upflow-downflow siliceous sand/marble waste filtration system for treatment and reuse of grey water collected from bathrooms of the student residential complex at the Higher Institute of Engineering Medjez El Bab (Tunisia). Once the optimization of grey water pre-treatment system has been determined, the filtration system was operated at different hydraulic loading rate and media filter proportions in order to assess the suitability of treated grey water for irrigational purpose according to salinity hazard, sodium hazard, magnesium hazard, permeability index, water infiltration rate, and widely used graphical methods. Suitability of the treated grey water for industrial purpose was evaluated in terms of foaming, corrosion, and scaling. Under optimal operational conditions, results reveals that treated grey water samples with an upflow-downflow siliceous sand/marble waste filtration system may be considered as a good and an excellent water quality suitable for irrigation purpose. However, treated grey water was found not appropriate for industrial purpose due to high concentrations of calcium and sodium that can generate foaming and scaling harm to boilers. These results suggest that treated grey water with an upflow-downflow siliceous sand/marble waste filtration system would support production when used as irrigation water.

  8. Biodegradation in a Partially Saturated Sand Matrix: Compounding Effects of Water Content, Bacterial Spatial Distribution, and Motility

    DEFF Research Database (Denmark)

    Dechesne, Arnaud; Owsianiak, Mikolaj; Bazire, Alexis

    2010-01-01

    colonizing these zones or on pollutant mass transfer to neighboring zones containing degraders. In a model system, we quantified the role exerted by water on mineralization rate in the context of a heterogeneously distributed degradation potential. Alginate beads colonized by Pseudomonas putida KT2440 were......Bacterial pesticide degraders are generally heterogeneously distributed in soils, leaving soil volumes devoid of degradation potential. This is expected to have an impact on degradation rates because the degradation of pollutant molecules in such zones will be contingent either on degraders...... inserted at prescribed locations in sand microcosms so that the initial spatial distribution of the mineralization potential was controlled. The mineralization rate was strongly affected by the matric potential (decreasing rate with decreasing matric potential) and by the initial distribution...

  9. Depth investigation of rapid sand filters for drinking water production reveals strong stratification in nitrification biokinetic behavior

    DEFF Research Database (Denmark)

    Tatari, Karolina; Smets, Barth F.; Albrechtsen, Hans-Jørgen

    2016-01-01

    The biokinetic behavior of NH4 + removal was investigated at different depths of a rapid sand filter treating groundwater for drinking water preparation. Filter materials from the top, middle and bottom layers of a full-scale filter were exposed to various controlled NH4 + loadings in a continuous......-flow lab-scale assay. NH4 + removal capacity, estimated from short term loading up-shifts, was at least 10 times higher in the top than in the middle and bottom filter layers, consistent with the stratification of Ammonium Oxidizing Bacteria (AOB). AOB density increased consistently with the NH4 + removal...... rate, indicating their primarily role in nitrification under the imposed experimental conditions. The maximum AOB cell specific NH4 + removal rate observed at the bottom was at least 3 times lower compared to the top and middle layers. Additionally, a significant up-shift capacity (4.6 and 3.5 times...

  10. Yeasts and coliform bacteria of water accumulated in bromeliads of mangrove and sand dune ecosystems of southeast Brazil.

    Science.gov (United States)

    Hagler, A N; Rosa, C A; Morais, P B; Mendonça-Hagler, L C; Franco, G M; Araujo, F V; Soares, C A

    1993-10-01

    Yeasts and coliform bacteria were isolated from water that accumulated in the central cups and adjacent leaf axilae of two bromeliads, Neoregelia cruenta of a coastal sand dune and Quesnelia quesneliana of a mangrove ecosystem near the city of Rio de Janeiro, Brazil. The mean total coliform counts were above 10,000 per 100 mL for waters of both plants, but the mean fecal coliform counts were only 74 per 100 mL for Q. quesneliana and mostly undetected in water from N. cruenta. Of 90 fecal coliform isolates, 51 were typical of Escherichia coli in colony morphology and indol, methyl red, Volges-Proskauer, and citrate (IMViC) tests. Seven representatives of the typical E. coli cultures were identified as this species, but the identifications of nine other coliform bacteria were mostly dubious. The yeast community of N. cruenta was typical of plant surfaces with basidiomycetous yeasts anamorphs, and the black yeast Aureobasidium pullulans was prevalent. Quesnelia quesneliana had a substantial proportion of ascomycetous yeasts and their anamorphs, including a probable new biotype of Saccharomyces unisporus. Our results suggested that the microbial communities in bromeliad waters are typically autochtonous and not contaminants.

  11. Effect of injection water quality on permeability of productive sands in Shaimsk group of oil fields

    Energy Technology Data Exchange (ETDEWEB)

    Andreeva, N I; Ivanov, V N; Lazarev, V N; Maksimov, V P

    1966-01-01

    Water from the Kond River is used to flood Shaimsk oil fields. Effect of raw and filtered waters on permeability of Shaimsk cores was experimentally determined. The raw river water contained 26 mg/liter of suspended solids, 10.7 mg/liter of total iron, 4.3 mg/liter of suspended iron oxide, and a pH of 6.4. The filtered river water was free of suspended solids and had a pH of 6.2. It was found that both raw and filtered water decreased core permeability. The unfiltered water decreased permeability 2 to 7 times more than the filtered water. Also, the decrease in permeability occurs much more slowly with the filtered than the unfiltered water. The effect of water on core permeability is essentially irreversible. Efforts to restore core permeability by reversing flow direction were not successful. Among the reasons for the permeability decrease were hydration and swelling of clays and evolution of gases from water in the cores. (10 refs.)

  12. Hydrogeologic characteristics and water quality of a confined sand unit in the surficial aquifer system, Hunter Army Airfield, Chatham County, Georgia

    Science.gov (United States)

    Gonthier, Gerard

    2012-01-01

    An 80-foot-deep well (36Q397, U.S. Geological Survey site identification 320146081073701) was constructed at Hunter Army Airfield to assess the potential of using the surficial aquifer system as a water source to irrigate a ballfield complex. A 300-foot-deep test hole was drilled beneath the ballfield complex to characterize the lithology and water-bearing characteristics of sediments above the Upper Floridan aquifer. The test hole was then completed as well 36Q397 open to a 19-foot-thick shallow, confined sand unit contained within the surficial aquifer system. A single-well, 24-hour aquifer test was performed by pumping well 36Q397 at a rate of 50 gallons per minute during July 13-14, 2011, to characterize the hydrologic properties of the shallow, confined sand unit. Two pumping events prior to the aquifer test affected water levels. Drawdown during all three pumping events and residual drawdown during recovery periods were simulated using the Theis formula on multiple changes in discharge rate. Simulated drawdown and residual drawdown match well with measured drawdown and residual drawdown using values of horizontal hydraulic conductivity and specific storage, which are typical for a confined sand aquifer. Based on the hydrologic parameters used to match simulated drawdown and residual drawdown to measured drawdown and residual drawdown, the transmissivity of the sand was determined to be about 400 feet squared per day. The horizontal hydraulic conductivity of the sand was determined to be about 20 feet per day. Analysis of a water-quality sample indicated that the water is suitable for irrigation. Sample analysis indicated a calcium-carbonate type water having a total dissolved solids concentration of 39 milligrams per liter. Specific conductance and concentrations of all analyzed constituents were below those that would be a concern for irrigation, and were below primary and secondary water-quality criteria levels.

  13. Septic systems as sources of organic wastewater compounds in domestic drinking water wells in a shallow sand and gravel aquifer

    Energy Technology Data Exchange (ETDEWEB)

    Schaider, Laurel A., E-mail: schaider@silentspring.org; Ackerman, Janet M.; Rudel, Ruthann A.

    2016-03-15

    Domestic drinking water wells serve 44 million people in the US and are common globally. They are often located in areas served by onsite wastewater treatment systems, including septic systems, which can be sources of biological and chemical pollutants to groundwater. In this study we tested 20 domestic drinking water wells in a sand and gravel aquifer on Cape Cod, Massachusetts, USA, for 117 organic wastewater compounds (OWCs) and for inorganic markers of septic system impact. We detected 27 OWCs, including 12 pharmaceuticals, five per- and polyfluoroalkyl substances (PFASs), four organophosphate flame retardants, and an artificial sweetener (acesulfame). Maximum concentrations of several PFASs and pharmaceuticals were relatively high compared to public drinking water supplies in the US. The number of detected OWCs and total concentrations of pharmaceuticals and of PFASs were positively correlated with nitrate, boron, and acesulfame and negatively correlated with well depth. These wells were all located in areas served exclusively by onsite wastewater treatment systems, which are likely the main source of the OWCs in these wells, although landfill leachate may also be a source. Our results suggest that current regulations to protect domestic wells from pathogens in septic system discharges do not prevent OWCs from reaching domestic wells, and that nitrate, a commonly measured drinking water contaminant, is a useful screening tool for OWCs in domestic wells. Nitrate concentrations of 1 mg/L NO{sub 3}-N, which are tenfold higher than local background and tenfold lower than the US federal drinking water standard, were associated with wastewater impacts from OWCs in this study. - Highlights: • We tested 20 domestic drinking water wells for 117 organic wastewater compounds. • PFASs, pharmaceuticals, and an artificial sweetener were most frequently detected. • Nitrate, boron, and well depth were all correlated with PFASs and pharmaceuticals. • Acesulfame

  14. Septic systems as sources of organic wastewater compounds in domestic drinking water wells in a shallow sand and gravel aquifer

    International Nuclear Information System (INIS)

    Schaider, Laurel A.; Ackerman, Janet M.; Rudel, Ruthann A.

    2016-01-01

    Domestic drinking water wells serve 44 million people in the US and are common globally. They are often located in areas served by onsite wastewater treatment systems, including septic systems, which can be sources of biological and chemical pollutants to groundwater. In this study we tested 20 domestic drinking water wells in a sand and gravel aquifer on Cape Cod, Massachusetts, USA, for 117 organic wastewater compounds (OWCs) and for inorganic markers of septic system impact. We detected 27 OWCs, including 12 pharmaceuticals, five per- and polyfluoroalkyl substances (PFASs), four organophosphate flame retardants, and an artificial sweetener (acesulfame). Maximum concentrations of several PFASs and pharmaceuticals were relatively high compared to public drinking water supplies in the US. The number of detected OWCs and total concentrations of pharmaceuticals and of PFASs were positively correlated with nitrate, boron, and acesulfame and negatively correlated with well depth. These wells were all located in areas served exclusively by onsite wastewater treatment systems, which are likely the main source of the OWCs in these wells, although landfill leachate may also be a source. Our results suggest that current regulations to protect domestic wells from pathogens in septic system discharges do not prevent OWCs from reaching domestic wells, and that nitrate, a commonly measured drinking water contaminant, is a useful screening tool for OWCs in domestic wells. Nitrate concentrations of 1 mg/L NO_3-N, which are tenfold higher than local background and tenfold lower than the US federal drinking water standard, were associated with wastewater impacts from OWCs in this study. - Highlights: • We tested 20 domestic drinking water wells for 117 organic wastewater compounds. • PFASs, pharmaceuticals, and an artificial sweetener were most frequently detected. • Nitrate, boron, and well depth were all correlated with PFASs and pharmaceuticals. • Acesulfame (artificial

  15. Survival of organic materials in hypervelocity impacts of ice on sand, ice, and water in the laboratory.

    Science.gov (United States)

    Burchell, Mark J; Bowden, Stephen A; Cole, Michael; Price, Mark C; Parnell, John

    2014-06-01

    The survival of organic molecules in shock impact events has been investigated in the laboratory. A frozen mixture of anthracene and stearic acid, solvated in dimethylsulfoxide (DMSO), was fired in a two-stage light gas gun at speeds of ~2 and ~4 km s(-1) at targets that included water ice, water, and sand. This involved shock pressures in the range of 2-12 GPa. It was found that the projectile materials were present in elevated quantities in the targets after impact and in some cases in the crater ejecta as well. For DMSO impacting water at 1.9 km s(-1) and 45° incidence, we quantify the surviving fraction after impact as 0.44±0.05. This demonstrates successful transfer of organic compounds from projectile to target in high-speed impacts. The range of impact speeds used covers that involved in impacts of terrestrial meteorites on the Moon, as well as impacts in the outer Solar System on icy bodies such as Pluto. The results provide laboratory evidence that suggests that exogenous delivery of complex organic molecules from icy impactors is a viable source of such material on target bodies.

  16. Pretreatment of worn waters of the dairy industry by sand filtration process

    International Nuclear Information System (INIS)

    Bouzid, H.; Derriche, Z.; Bettahar, N.

    2009-01-01

    The problem of the environment started to become a concern with the demographic increase and the industrial and agricultural development, especially in the great agglomeration, the relative increase out of water became a major concern. Water of the factories takes care of mineral substances and organics during manufacture and constitutes one of the principal sources of contamination of the environment. (Author)

  17. Pore water chemistry in the beach sands of central Tamil Nadu, India

    Digital Repository Service at National Institute of Oceanography (India)

    Chandrasekar, N.; Gujar, A.R.; Loveson, V.J.; Rajamanickam, G.V.; Moscow, S.; Manickaraj, D.S.; Chandrasekaran, R.; Chaturvedi, S.K.; Mahesh, R.; Sudha, V.; Josephine, P.J.; Deepa, V.

    As the pore water chemistry- has been considered as one of the prominent base parameters to infer the impact of coastal mining in introducing environmental deterioration, a study in pore water chemistry is planned here along the beaches for a length...

  18. Checking technical measurements on climatic data during sand blasting and spraying work in the condensation chamber of the boiling water reactor Gundremmingen

    International Nuclear Information System (INIS)

    Rausch, D.; Unte, U.

    1986-01-01

    During sand blasting and spraying work in the condensation chambers of boiling water reactors prescribed climatic data must be adhered to. For this purpose temporary air conditioners are used. The technical measurement examination here should provide information as to whether the air conditioners used were to fulfill the parameter curve specifications. (orig.) [de

  19. Conditions and processes affecting radionuclide transport

    Science.gov (United States)

    Simmons, Ardyth M.; Neymark, Leonid A.

    2012-01-01

    Characteristics of host rocks, secondary minerals, and fluids would affect the transport of radionuclides from a previously proposed repository at Yucca Mountain, Nevada. Minerals in the Yucca Mountain tuffs that are important for retarding radionuclides include clinoptilolite and mordenite (zeolites), clay minerals, and iron and manganese oxides and hydroxides. Water compositions along flow paths beneath Yucca Mountain are controlled by dissolution reactions, silica and calcite precipitation, and ion-exchange reactions. Radionuclide concentrations along flow paths from a repository could be limited by (1) low waste-form dissolution rates, (2) low radionuclide solubility, and (3) radionuclide sorption onto geological media.

  20. Zirconium oxide-coated sand based batch and column adsorptive removal of arsenic from water: Isotherm, kinetic and thermodynamic studies

    Directory of Open Access Journals (Sweden)

    Saif Ali Chaudhry

    2017-06-01

    Full Text Available This paper reports zirconium oxide-coated sand preparation, characterization by SEM, EDX, XRD, FT-IR and thermoanalytical techniques, and use as an adsorbent for the removal of most toxic form of arsenic, As(III, from aqueous solution in both batch and column methods. Batch experimental parameters such as contact time, concentration, dose of adsorbent, pH of As(III solution and temperature were optimized. The adsorption data was fitted to Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherms at 303, 308 and 313 K. The maximum Langmuir monolayer adsorption capacity was found to be 136.98 μg/g at 313 K. Values of ΔH°, ΔG° and ΔS° were found to be −12.90, −8.74 to –8.28 and 0.014 kJ/mol, suggesting exothermic and spontaneous adsorption process with slight increase in entropy. The adsorption process followed pseudo-second order kinetics and was controlled by film diffusion step. The column studies showed that when flow rate was increased from 3.0 to 5.0 mL/min, the arsenic adsorption capacity of ZrOCS increased from 33.104 to 42.231 μg/g and breakthrough, and exhaustion times got reduced reduced. The results indicated that zirconium oxide-coated sand (ZrOCS is an excellent adsorbent for the removal of As(III from water.

  1. Processes Affecting Groundwater Quality in the La Digue Aquifer, Seychelles

    Energy Technology Data Exchange (ETDEWEB)

    Alcindor, A. [Public Utilities Corporation, Victoria (Seychelles); Sacchi, E. [Dipartimento di Scienze della Terra e dell' ambiente, Universita di Pavia (Italy); Taigbenu, A. E. [University of the Witwatersrand, Johannesburg (South Africa)

    2013-07-15

    This paper presents the results obtained by the public utilities corporation (PUC), within the framework of an IAEA TC project, which aims to evaluate the potential of the la digue aquifer. Several monitoring activities and hydrochemical and isotopic surveys have been conducted. Results indicate the presence of brackish water at shallow depths, and low redox potentials, attesting to the presence of H{sub 2}S and heavy metals. Groundwater quality is affected by the concomitant presence of different adverse factors, namely aquifer characteristics, hydrogeology, and anthropogenic pressure. In addition, seawater penetrates the river course during high tides and infiltrates through the recharge area of the aquifer that is close to the actual pumping station. The positioning of non return high tide gates, an easy and low cost intervention, could enhance groundwater quality. The understanding of the main processes affecting groundwater quality helped in the identification of areas favourable for new wells, located at higher elevations. (author)

  2. Septic systems as sources of organic wastewater compounds in domestic drinking water wells in a shallow sand and gravel aquifer.

    Science.gov (United States)

    Schaider, Laurel A; Ackerman, Janet M; Rudel, Ruthann A

    2016-03-15

    Domestic drinking water wells serve 44 million people in the US and are common globally. They are often located in areas served by onsite wastewater treatment systems, including septic systems, which can be sources of biological and chemical pollutants to groundwater. In this study we tested 20 domestic drinking water wells in a sand and gravel aquifer on Cape Cod, Massachusetts, USA, for 117 organic wastewater compounds (OWCs) and for inorganic markers of septic system impact. We detected 27 OWCs, including 12 pharmaceuticals, five per- and polyfluoroalkyl substances (PFASs), four organophosphate flame retardants, and an artificial sweetener (acesulfame). Maximum concentrations of several PFASs and pharmaceuticals were relatively high compared to public drinking water supplies in the US. The number of detected OWCs and total concentrations of pharmaceuticals and of PFASs were positively correlated with nitrate, boron, and acesulfame and negatively correlated with well depth. These wells were all located in areas served exclusively by onsite wastewater treatment systems, which are likely the main source of the OWCs in these wells, although landfill leachate may also be a source. Our results suggest that current regulations to protect domestic wells from pathogens in septic system discharges do not prevent OWCs from reaching domestic wells, and that nitrate, a commonly measured drinking water contaminant, is a useful screening tool for OWCs in domestic wells. Nitrate concentrations of 1mg/L NO3-N, which are tenfold higher than local background and tenfold lower than the US federal drinking water standard, were associated with wastewater impacts from OWCs in this study. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  3. 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.

  4. Water saturation in shaly sands: logging parameters from log-derived values

    International Nuclear Information System (INIS)

    Miyairi, M.; Itoh, T.; Okabe, F.

    1976-01-01

    The methods are presented for determining the relation of porosity to formation factor and that of true resistivity of formation to water saturation, which were investigated through the log interpretation of one of the oil and gas fields of northern Japan Sea. The values of the coefficients ''a'' and ''m'' in porosity-formation factor relation are derived from cross-plot of porosity and resistivity of formation corrected by clay content. The saturation exponent ''n'' is determined from cross-plot of porosity and resistivity index on the assumption that the product of porosity and irreducible water saturation is constant. The relation of porosity to irreducible water saturation is also investigated from core analysis. The new logging parameters determined from the methods, a = 1, m = 2, n = 1.4, improved the values of water saturation by 6 percent in average, and made it easy to distinguish the points which belong to the productive zone and ones belonging to the nonproductive zone

  5. Water, Energy and Carbon Balance Research: Recovery Trajectories For Oil Sands Reclamation and Disturbed Watersheds in the Western Boreal Forest

    Science.gov (United States)

    Petrone, R. M.; Carey, S. K.

    2014-12-01

    The Oil Sand Region (OSR) of North-Central Alberta exists within the sub-humid Boreal Plains (BP) ecozone, with a slight long-term moisture deficit regime. Despite this deficit, the BP is comprised of productive wetland and mixed wood (aspen and conifer dominated) forests. Reclamation activities are now underway at a large number of surface mining operations in the OSR, where target ecosystems are identified, soil prescriptions placed and commercial forest species planted. Some watersheds have been created that now contain wetlands. However, recent work in the BP suggests that over time wetlands supply moisture for the productivity of upland forests. Thus, water use of reclaimed forests is going to be critical in determining the sustainability of these systems and adjacent wetlands, and whether in time, either will achieve some form of equivalent capability that will allow for certification by regulators. A critical component in the success of any reclamation is that sufficient water is available to support target ecosystems through the course of natural climate cycles in the region. Water Use Efficiency (WUE), which links photosynthesis (GEP) with water use (Evapotranspiration (ET)), provides a useful metric to compare ecosystems and evaluate their utilization of resources. In this study, 41 site years of total growing season water and carbon flux data over 8 sites (4 reclamation, 4 regeneration) were evaluated using eddy covariance micrometeorological towers. WUE shows clear discrimination among ecosystem types as aspen stands assimilate more carbon per unit weight of water than conifers. WUEs also change with time as ecosystems become more effective at transpiring water through plant pathways compared with bare-soil evaporation, which allows an assessment of ability to limit water loss without carbon uptake. In addition, clonal rooting systems allow aspen forests to recover quicker after disturbance than reclamation sites in terms of their WUE. For reclamation

  6. Ecological restoration and recovery in the wind-blown sand hazard areas of northern China: relationship between soil water and carrying capacity for vegetation in the Tengger Desert.

    Science.gov (United States)

    Li, XingRong; Zhang, ZhiShan; Tan, HuiJuan; Gao, YanHong; Liu, LiChao; Wang, XingPing

    2014-05-01

    The main prevention and control area for wind-blown sand hazards in northern China is about 320000 km(2) in size and includes sandlands to the east of the Helan Mountain and sandy deserts and desert-steppe transitional regions to the west of the Helan Mountain. Vegetation recovery and restoration is an important and effective approach for constraining wind-blown sand hazards in these areas. After more than 50 years of long-term ecological studies in the Shapotou region of the Tengger Desert, we found that revegetation changed the hydrological processes of the original sand dune system through the utilization and space-time redistribution of soil water. The spatiotemporal dynamics of soil water was significantly related to the dynamics of the replanted vegetation for a given regional precipitation condition. The long-term changes in hydrological processes in desert areas also drive replanted vegetation succession. The soil water carrying capacity of vegetation and the model for sand fixation by revegetation in aeolian desert areas where precipitation levels are less than 200 mm are also discussed.

  7. 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.

  8. Protocol for Measuring the Thermal Properties of a Supercooled Synthetic Sand-water-gas-methane Hydrate Sample.

    Science.gov (United States)

    Muraoka, Michihiro; Susuki, Naoko; Yamaguchi, Hiroko; Tsuji, Tomoya; Yamamoto, Yoshitaka

    2016-03-21

    Methane hydrates (MHs) are present in large amounts in the ocean floor and permafrost regions. Methane and hydrogen hydrates are being studied as future energy resources and energy storage media. To develop a method for gas production from natural MH-bearing sediments and hydrate-based technologies, it is imperative to understand the thermal properties of gas hydrates. The thermal properties' measurements of samples comprising sand, water, methane, and MH are difficult because the melting heat of MH may affect the measurements. To solve this problem, we performed thermal properties' measurements at supercooled conditions during MH formation. The measurement protocol, calculation method of the saturation change, and tips for thermal constants' analysis of the sample using transient plane source techniques are described here. The effect of the formation heat of MH on measurement is very small because the gas hydrate formation rate is very slow. This measurement method can be applied to the thermal properties of the gas hydrate-water-guest gas system, which contains hydrogen, CO2, and ozone hydrates, because the characteristic low formation rate of gas hydrate is not unique to MH. The key point of this method is the low rate of phase transition of the target material. Hence, this method may be applied to other materials having low phase-transition rates.

  9. Water Quality, Weather and Environmental Factors Associated with Fecal Indicator Organism Density in Beach Sand at Two Recreational Marine Beaches

    Science.gov (United States)

    Recent studies showing an association between fecal indicator organisms (FIOs and gastrointestinal (GI) illness among beachgoers wit sand contact have important public health implicatons because of the large numbers of people who recreate at beaches and engage in sand contact act...

  10. Importance of copper for nitrification in biological rapid sand filters for drinking water production

    DEFF Research Database (Denmark)

    Wagner, Florian Benedikt

    nitrification during drinking water production provided the motivation to investigate if a lack of copper could be responsible for the problems in nitrifying biofilters. Copper is believed to be an essential cofactor in the enzyme ammonia monooxygenase (AMO), which catalyzes the first essential step...... be supplied in a controlled fashion, and that little maintenance and no chemicals are required. Copper dosing through the novel electrolysis method, as well as through passive dosing from solid copper and active dosing of copper solution, was studied at nine more DWTPs, which all shared a long history...... and chemical speciation modelling were carried out for Nærum DWTP. Results showed that substantial amounts of copper were bound to iron oxide-hydroxides in the filter and that bicarbonate heavily complexed copper in the water phase. Only total copper...

  11. Petrophysical studies in heavy oil sands with early water production - Hamaca area, Orinoco Oil Belt

    Energy Technology Data Exchange (ETDEWEB)

    Salisch, H.A.

    1982-07-01

    This study describes the main lines of petrophysical research in the Hamaca-Pao region of the Orinoco Oil Belt. The techniques and parameters most appropriate for petrophysical studies in the area of interest are discussed. Field tests have confirmed the conclusions of this study on early water production and low oil recovery. Steam injection was shown to be a means for increasing oil mobility to such a degree that significant amounts of additional oil can be produced.

  12. Computational Simulation of High-Speed Projectiles in Air, Water, and Sand

    Science.gov (United States)

    2007-12-03

    Supercavitating projectiles can be used for underwater mine neutralization, beach and surf zone mine clearance, littoral ASW, and neutralizing combat...swimmer systems. The water entry phase of flight is interesting and challenging due to projectile transitioning from flight in air to supercavitating ...is formed. Neaves and Edwards [1] simulated this case using a supercavitation code developed at NSWC-PC. The results presented are in good agreement

  13. Effect of pore water pressure on P-wave velocity in water-filled sands with partial air saturation; Fukanzen howa jotai no suna shiryo wo denpasuru P ha sokudo ni oyobosu kangeki suiatsu no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Kanema, T [Chishitsu-Keisoku Co. Ltd., Tokyo (Japan)

    1997-10-22

    With an objective to elucidate change in velocity of elastic waves in association with water pressure increase in a sand bed below the groundwater level in a shallow portion of the ground, a measurement experiment was carried out on P-wave velocity in sand samples with partial air saturation. The experiment has used fine sand having an equivalent coefficient of 2.40, a soil particle density of 2.68 g/cm {sup 3} or 60%, and a grain size of 0.36 mm. Inside the water-filled sand sample, two accelerometers were embedded 20 cm apart from each other as vibration receivers. An electromagnetic hammer for P-wave was used as the vibration source. In the experiment, measurement was carried out on the P-wave velocity in association with increase in pore water pressure by applying water pressure afresh to the water-filled sample. As a result of the experiment, the following matters were disclosed: the P-wave velocity increases as the pore water pressure was increased, and a phenomenon was recognized that the dominant frequency changes into high frequency; the degree of increase in the P-wave velocity varies depending on initial saturation of the sample; and bubbles in the pore fluid have their volume decreased due to compression resulted from increased pore water pressure and dissolution of air into the pore water. 6 refs., 11 figs.

  14. The kinetics of activation and deactivation in the process of water ozonising used for advanced oxidation of the dust waste from moulding sands

    Directory of Open Access Journals (Sweden)

    A. Baliński

    2009-01-01

    Full Text Available Adding coal dust and organic carriers of the lustrous carbon to bentonite-bonded moulding sands in amounts justified by thetechnological regime and the use of cores and protective coatings based on organic compounds create serious threats to the environment.During thermal destruction of the individual components of moulding and core sands, some toxic organic compounds are emitted. They formthe majority of the Hazardous Air Pollutants (HAPs, and include mainly compounds like benzene, toluene, xylene, naphtalene, hexane,acetaldehyde, acrolein, aniline, cresol and cumene, their polycyclic derivatives, phenol, formaldehyde, and other similar matters. In thusformed dust waste, the amount of which constitutes about 20% of all the waste from foundries using traditional moulding and core sands, there are still full-value materials which can undergo total recycling, providing the HAPs are partially or totally removed from them. The article discusses some problems of the advanced oxidation of selected toxic chemical compounds present in bentonite-bonded moulding sands due to the effect of high temperature. The results of the investigations of the kinetics of the process of maximum water saturation with ozone (acting as an oxidiser and of the kinetics of the natural process of ozone decomposition to diatomic oxygen were presented. It has been stated that the maximum time of water saturation with ozone using an OZOMATIC OSC-MODULAR 4HC ozone generator and a 1m3 capacity tank with water is 60 minutes. After 30 minute break in the ozonising process, the ozone concentration in water decreases by 40 to 50%. To obtain maximum ozone concentration in water during the next ozonising cycle, it is necessary to have the ozone-generating device running for the next 30 minutes. The stabilisation of ozone concentration in water takes place only after the third ozonising cycle, when it reaches nearly 80%of the maximum value obtained after the first process cycle

  15. Microbial oxidation of soluble sulfide in produced water from the Bakkeen Sands

    Energy Technology Data Exchange (ETDEWEB)

    Gevertz, D.; Zimmerman, S. [Agouron Institute, La Jolla, CA (United States); Jenneman, G.E. [Phillips Petroleum Company, Bartlesville, OK (United States)] [and others

    1995-12-31

    The presence of soluble sulfide in produced water results in problems for the petroleum industry due to its toxicity, odor, corrosive nature, and potential for wellbore plugging. Sulfide oxidation by indigenous nitrate-reducing bacteria (NRB) present in brine collected from wells at the Coleville Unit (CVU) in Saskatchewan, Canada, was investigated. Sulfide oxidation took place readily when nitrate and phosphate were added to brine enrichment cultures, resulting in a decrease in sulfide levels of 99-165 ppm to nondetectable levels (< 3.3 ppm). Produced water collected from a number of producing wells was screened to determine the time required for complete sulfide oxidation, in order to select candidate wells for treatment. Three wells were chosen, based on sulfide removal in 48 hours or less. These wells were treated down the backside of the annulus with a solution containing 10 mM KNO{sub 3} and 100 {mu}M NaH{sub 2}PO{sub 4}. Following a 24- to 72-hour shut-in, reductions in pretreatment sulfide levels of greater than 90% were observed for two of the wells, as well as sustained sulfide reductions of 50% for at least two days following startup. NRB populations in the produced brine were observed to increase significantly following treatment, but no significant increases in sulfate-reducing bacteria were observed. These results demonstrate the technical feasibility of stimulating indigenous populations of NRB to remediate and control sulfide in produced brine.

  16. A Molecular MST Approach to Investigate Fecal Indicator Bacteria in Bioaerosols, Bathing Water, Seaweed Wrack, and Sand at Recreational Beaches

    Science.gov (United States)

    Thoren, K. M.; Sinigalliano, C. D.

    2016-02-01

    Despite numerous cases of beach bacteria affecting millions of people worldwide, the persistence of the bacteria populations in coastal areas is still not well understood. The purpose of this study was to test the levels of persistence of Fecal Indicating Bacteria (FIB) of enterococci, Escherichia coli, and Human-source Bacteroidales, within the intertidal "swash zone" and the deeper waist zone in which people commonly bathe and play. In addition, the study sought to determine if these bacterial contaminants may also be found in aerosols at the beach. Measuring solar insolation in relation to bacterial persistence in seaweed wrack was used to determine if sunlight plays a role in modifying concentrations of FIB at the beach. Light intensity measured by a solar photometer and air quality measured by aerosol plate counts and qPCR Microbial Source Tracking (MST) was compared to varying locations where the beach samples were collected. Results from water samples demonstrate that bacteria measured using plate counts and qPCR were indeed higher within the swash zone than in the waist zone. This is in contrast with the way that the EPA currently measures and determines the public safety of beach waters. They commonly measure the waist zone, but disregard the swash zone. Results from beach bio-aerosol samples showed a wide variety of fungi and bacteria in the beach air, and qPCR MST analysis of these bio-aerosols showed the presence of FIBs such as enterococci on several of the aerosol collection plates. This emphasizes the need to collect samples from the entire beach instead of just measuring at an isolated area, and that exposure to microbial contaminants may include bathing water, beach sand, seaweed wrack, and bio-aerosols. Thus, the data reveals a potential way to identify harmful levels of bacteria and dangerous levels of poor air quality at recreational beaches. These results expound the need for broader assessment of potential beach contamination, not only the

  17. 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.

  18. Beyond Naphthenic Acids: Environmental Screening of Water from Natural Sources and the Athabasca Oil Sands Industry Using Atmospheric Pressure Photoionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry.

    Science.gov (United States)

    Barrow, Mark P; Peru, Kerry M; Fahlman, Brian; Hewitt, L Mark; Frank, Richard A; Headley, John V

    2015-09-01

    There is a growing need for environmental screening of natural waters in the Athabasca region of Alberta, Canada, particularly in the differentiation between anthropogenic and naturally-derived organic compounds associated with weathered bitumen deposits. Previous research has focused primarily upon characterization of naphthenic acids in water samples by negative-ion electrospray ionization methods. Atmospheric pressure photoionization is a much less widely used ionization method, but one that affords the possibility of observing low polarity compounds that cannot be readily observed by electrospray ionization. This study describes the first usage of atmospheric pressure photoionization Fourier transform ion cyclotron resonance mass spectrometry (in both positive-ion and negative-ion modes) to characterize and compare extracts of oil sands process water, river water, and groundwater samples from areas associated with oil sands mining activities. When comparing mass spectra previously obtained by electrospray ionization and data acquired by atmospheric pressure photoionization, there can be a doubling of the number of components detected. In addition to polar compounds that have previously been observed, low-polarity, sulfur-containing compounds and hydrocarbons that do not incorporate a heteroatom were detected. These latter components, which are not amenable to electrospray ionization, have potential for screening efforts within monitoring programs of the oil sands.

  19. Comparison of grey water treatment performance by a cascading sand filter and a constructed wetland.

    Science.gov (United States)

    Kadewa, W W; Le Corre, K; Pidou, M; Jeffrey, P J; Jefferson, B

    2010-01-01

    A novel unplanted vertical flow subsurface constructed wetland technology comprising three shallow beds (0.6 m length, 0.45 m width and 0.2 m depth) arranged in a cascading series and a standard single-pass Vertical Flow Planted Constructed Wetland (VFPCW, 6 m² and 0.7 m depth) were tested for grey water treatment. Particular focus was on meeting consent for published wastewater reuse parameters and removal of anionic surfactants. Treatment performance at two hydraulic loading rates (HLR) of 0.08, and 0.17 m³ m⁻² d⁻¹ were compared. Both technologies effectively removed more than 90% turbidity and more than 96% for organics with the prototype meeting the most stringent reuse standard of < 2 NTU and <10 mg/L. However, surfactant removal in the VFPCW was higher (76-85%) than in the prototype which only achieved more than 50% removal at higher loading rate. Generally, the prototype performed consistently better than the VFPCW except for surfactant removal. However, at higher loading rates, both systems did not meet the reuse standard of <1 mg L⁻¹ for anionic surfactants. This observation confirms that shallow beds provide a more oxidised environment leading to higher BOD₅ and COD removals. Presence of plants in the VFPCW led to higher anionic surfactant removal, through increased microbial and sorption processes.

  20. Conversion of sand filters into activated carbon filters at the La Presa (Valencia) water works; Conversion de filtros de arena porcarbon activo en la ETAP de La Presa (Valencia)

    Energy Technology Data Exchange (ETDEWEB)

    Macian Cervera, V. J.; Monforte Monleon, L.; Ribera Orts, R.; Suris Jorda, J. I.; Klee, J. M.

    2007-07-01

    To improve the water quality at potable water treatment plant of La P esa (Valencia), the sand filters have been replaced for activated carbon filters. In the following review the results and conclusions of the direct sand filter conversion into activated carbon filters will be presented. The leads to a simple and fast solution to odour and taste removal, as well as dissolved organic matter, without investments in works at the water works. (Author)

  1. Bituminous sands : tax issues

    International Nuclear Information System (INIS)

    Patel, B.

    2004-01-01

    This paper examined some of the tax issues associated with the production of bitumen or synthetic crude oil from oil sands. The oil sands deposits in Alberta are gaining more attention as the supplies of conventional oil in Canada decline. The oil sands reserves located in the Athabasca, Cold Lake and Peace River areas contain about 2.5 trillion barrels of highly viscous hydrocarbons called bitumen, of which nearly 315 billion barrels are recoverable with current technology. The extraction method varies for each geographic area, and even within zones and reservoirs. The two most common extraction methods are surface mining and in-situ extraction such as cyclic steam stimulation (CSS); low pressure steam flood; pressure cycle steam drive; steam assisted gravity drainage (SAGD); hot water flooding; and, fire flood. This paper also discussed the following general tax issues: bituminous sands definition; bituminous sands leases and Canadian development expense versus Canadian oil and gas property expense (COGPE); Canadian exploration expense (CEE) for surface mining versus in-situ methods; additional capital cost allowance; and, scientific research and experimental development (SR and ED). 15 refs

  2. Isotope-based partitioning of streamflow in the oil sands region, northern Alberta: Towards a monitoring strategy for assessing flow sources and water quality controls

    Directory of Open Access Journals (Sweden)

    J.J. Gibson

    2016-03-01

    Full Text Available Study region: This study is based on the rapidly developing Athabasca Oil Sands region, northeastern Alberta. Study focus: Hydrograph separation using stable isotopes of water is applied to partition streamflow sources in the Athabasca River and its tributaries. Distinct isotopic labelling of snow, rain, groundwater and surface water are applied to estimate the contribution of these sources to streamflow from analysis of multi-year records of isotopes in streamflow. New hydrological insights for the region: The results provide new insight into runoff generation mechanisms operating in six tributaries and at four stations along the Athabasca River. Groundwater, found to be an important flow source at all stations, is the dominant component of the hydrograph in three tributaries (Steepbank R., Muskeg R., Firebag R., accounting for 39–50% of annual streamflow. Surface water, mainly drainage from peatlands, is also found to be widely important, and dominant in three tributaries (Clearwater R., Mackay R., Ells R., accounting for 45–81% of annual streamflow. Fairly limited contributions from direct precipitation illustrate that most snow and rain events result in indirect displacement of pre-event water by fill and spill mechanisms. Systematic shifts in regional groundwater to surface-water ratios are expected to be an important control on spatial and temporal distribution of water quality parameters and useful for evaluating the susceptibility of rivers to climate and development impacts. Keywords: Stable isotopes, Hydrograph separation, Groundwater, Surface water, Snowmelt, Oil sands

  3. Comparison between Removal Efficiency of Slag, zeolite, and Conventional media in slow sand Filter for Removal of Lead and Cadmium from Water Resources

    Directory of Open Access Journals (Sweden)

    A Ebrahimi

    2016-03-01

    Full Text Available Introduction: Heavy metals owing to their health hazards and high toxicity in low concentration for human and environment have very concern and attention. Slow sand filter is one of the simple and cost-effective for removal of these pollutants. In this method, media play an important role for removal of pollutant. Therefore, the aim of this study was investigation of different media like slag, zeolite, and conventional media in slow sand filter for removal of lead and cadmium. Methods: In this research there are three beds filter include typical filter bed, slag and zeolite that used in pilot plant for investigation of lead and cadmium removal at three concentration of 0.1T 1 and 10 ppm. Each of filters has an internal diameter of 8 cm and a height of 120 cm with Plexiglas, which have a continuous flow operation. Results: The removal efficiency of turbidity by three typical filter bed, slag, and zeolite with initial turbidity of 13 NTU was 46%, 77%, and 89% respectively. Removal efficiency of lead without turbidity was 70.3%, 79%, and 59.8% respectively for 0.1 ppm lead. For 1 ppm, concentration of lead removal efficiency was 51.8%, 52.7% and 52.6% respectively and for 10 ppm it was 53.4%, 57.8%, and 59.8% respectively. Cadmium removal for these media was 23.4%, 37.5%, and 59.4% respectively at 0.1 ppm cadmium. At 1 ppm of cadmium concentration, it was 37.9%, 45% and 41.3% respectively and at 10 ppm concentration of cadmium it was 68.3%, 68.6% and 67% respectively. Conclusion: Slag and zeolite beds are more efficiently than the conventional sand beds in the slow sand filter, so it can be used instead of the usual sand for removing lead and cadmium from resources water.

  4. Late Pleistocene shallow water sand transported to the slope at IODP Sites U1484 and U1485 off the north coast of Papua New Guinea: how, when and why?

    Science.gov (United States)

    Mountain, G. S.; Browning, J. V.; Bova, S. C.

    2017-12-01

    IODP Exp 363 drilled two sites on a gently seaward-dipping terrace 18 and 21 km north of Papua New Guinea, enabling the study of mechanisms that bring shallow water sediment to the deep sea. We expect past changes in sea level and precipitation / fluvial run-off dominated this record, but additional processes may have been important. We examined Hole U1484B (1031 m water depth; 223 m drilled; 99.8% recovered) and detected 339 sharp-based sand layers 0.5 cm or more thick. In contrast to the background hemipelagic nanno-bearing silty clay, sand layers are graded or massive turbidites containing detrital grains, shallow-water benthic foraminifera, shell fragments and/or wood. δ18O values of Globigerinoides ruber tied to the isotopic curve of Lisiecki and Raymo (2004) show the densest concentration of sand layers in the last 310 ka occurred during the cooling trend of MIS stage 6. Stage 2 contains significantly fewer discrete sand beds, even during the coldest part of the LGM. Other times of glacial intensification show a similarly modest correlation to peak sand deposition. Sand layers strongly correlate with high values of magnetic susceptibility (MS) measured on unsplit cores, and when mapped to the MIS time scale, MS increases match times of ice growth / falling sea level more consistently than does the density of sand layers. We attribute this to reworking of discrete sand layers by bioturbation, indicating the need for caution tying the absence of sharp-based sands to times of transgression or low precipitation / fluvial run-off. Packages of especially thick and closely-spaced sharp-based sands match seismic reflections at Site U1484. Tracing these reflections throughout the grid of hi-res MCS site survey profiles reveals the areal distribution and transport path of sand as well as a direct tie to similar sharp-based sands in the more distal Hole U1485A (1145 m water depth; 301 m drilled; 103.8% recovered.) The distribution of sands through time might be

  5. Effect of probiotic and sand filtration treatments on water quality and growth of tilapia (Oreochromis niloticus) and pangas (Pangasianodon hypophthalmus) in earthen ponds of southern Bangladesh

    DEFF Research Database (Denmark)

    Mahmud, Sultan; Ali, Mohammad Lokman; Alam, Md Ariful

    2016-01-01

    Effects of water treatment by two probiotic products (PondPlus® and AquaPhoto®) and sand filtration were studied on growth performance of tilapia (Oreochromis niloticus) and pangas (Pangasianodon hypophthalmus) stocked at tilapia:pangas ratio of 5:3 in traditional earthen ponds in Bangladesh....... The fish were stocked at a density of 20,000 fish ha−1 and reared for 7 months. Compared to untreated ponds, treatments of probiotic products or sand filtration in earthen ponds resulted in a higher O2 content, higher water transparency, less ammonium, and fewer cyanobacteria. Weight gain for individual...... tilapia was lowest in the AquaPhoto-treated ponds (177 g), while similar gains (188–194 g) occurred in the other ponds. For pangas, the lowest weight gain (627 g) was obtained in the sand filter-treated ponds, as compared to 690–797 g in the other ponds. Thus, a general positive effect from the treatments...

  6. 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.

  7. On the study of ricochet and penetration in sand, water and gelatin by spheres, 7.62 mm APM2, and 25 mm projectiles

    Directory of Open Access Journals (Sweden)

    John F. Moxnes

    2016-04-01

    Full Text Available We examine the ricochet and penetration behavior in sand, water and gelatin by steel spheres, 7.62 mm APM2 and 25 mm projectiles. A threshold impact angle (critical angle exists beyond which ricochet cannot occur. The Autodyn simulation code with the smooth particle hydrodynamic (SPH method and Impetus Afea Solver with the corpuscular model are used and the results are compared with experimental and analytical results. The resistance force in sand for spheres was proportional to a term quadratic in velocity plus a term linear in velocity. The drag coefficient for the quadratic term was 0.65. The Autodyn and Impetus Afea codes simulate too large penetration due to the lack of a linear velocity resistance force. Critical ricochet angles were consistent with analytical results in the literature. In ballistic gelatin at velocities of 50–850 m/s a drag coefficient of 0.30 fits the high speed camera recordings if a linear velocity resistance term is included. However, only a quadratic velocity resistance force with drag coefficient that varies with the Reynolds number also fits the measurements. The simulation of a sphere in water with Autodyn showed too large drag coefficient. The 7.62 mm APM2 core simulations in sand fit reasonable well for both codes. The 25 mm projectile ricochet simulations in sand show consistency with the high speed camera recordings. Computer time was reduced by one to two orders of magnitudes when applying the Impetus Afea Solver compared to Autodyn code due to the use of the graphics processing units (GPU.

  8. New hybrid nanofluid containing encapsulated paraffin wax and sand nanoparticles in propylene glycol-water mixture: Potential heat transfer fluid for energy management

    International Nuclear Information System (INIS)

    Manikandan, S.; Rajan, K.S.

    2017-01-01

    Highlights: • Hybrid nanofluid containing sand nanoparticles & encapsulated paraffin wax prepared. • Specific heat of hybrid nanofluid 9% greater than that of PG-water mixture. • Specific heat & thermal conductivity enhanced at optimum paraffin wax concentration. • Hybrid nanofluid with 1 wt.% paraffin wax & 1 vol% sand nanoparticles best suited. - Abstract: The reduction in specific heat commonly encountered due to the addition of nanoparticles to a heat transfer fluid such as propylene glycol-water mixture, can be overcome by co-dispersing surfactant-encapsulated paraffin wax, leading to formation of a hybrid nanofluid. Experimental investigations have been carried out on the preparation and evaluation of thermophysical properties of a hybrid nanofluid containing pluronic P-123 encapsulated paraffin wax (70–120 nm diameter, 1–5 wt.%) and sand nanoparticles (1 vol%) in propylene glycol-water mixture. The comparison of results of differential scanning calorimetry of pure paraffin wax and encapsulated paraffin wax revealed encapsulation efficiency of 84.4%. The specific heat of hybrid nanofluids monotonously increased with paraffin wax concentration, with 9.1% enhancement in specific heat for hybrid nanofluid containing 5 wt.% paraffin wax, in comparison to propylene glycol-water mixture. There exists an optimum paraffin wax concentration (1 wt.%) for the hybrid nanofluid at which the combination of various thermophysical properties such as specific heat, thermal conductivity and viscosity are favorable for use as heat transfer fluid. Such a hybrid nanofluid can be used as a substitute for propylene glycol-water mixture in solar thermal systems.

  9. Bioaugmentation of rapid sand filters by microbiome priming with a nitrifying consortium will optimize production of drinking water from groundwater

    DEFF Research Database (Denmark)

    Albers, Christian Nyrop; Ellegaard-Jensen, Lea; Hansen, Lars Hestbjerg

    2018-01-01

    . It is shown that nitrifying communities could be enriched by microbiomes from well-functioning rapid sand filters in waterworks and that the enriched nitrifying consortium could be used to inoculate fresh filters, significantly shortening the time taken for the nitrification process to start. The key...

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. Modelling offshore sand wave evolution

    NARCIS (Netherlands)

    Nemeth, Attila; Hulscher, Suzanne J.M.H.; van Damme, Rudolf M.J.

    2007-01-01

    We present a two-dimensional vertical (2DV) flow and morphological numerical model describing the behaviour of offshore sand waves. The model contains the 2DV shallow water equations, with a free water surface and a general bed load formula. The water movement is coupled to the sediment transport

  15. Mineral sands

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    This paper presents an outlook of the Australian mineral sand industry and covers the major operators. It is shown that conscious of an environmentally minded public, the Australian miners have led the way in the rehabilitation of mined areas. Moreover the advanced ceramic industry is generating exciting new perspectives for zircon producers and there is a noticeable growth in the electronic market for rare earths, but in long term the success may depend as much on environmental management and communication skills as on mining and processing skills

  16. Oil sands and the environment

    Energy Technology Data Exchange (ETDEWEB)

    Seeley, R. [Shell Canada Ltd., Calgary, AB (Canada). Calgary Research Centre

    2004-07-01

    Oil sands are a significant resource for Alberta and Canada with continuing growth opportunity. There is a need to ensure sustainable development of the oil sands resources from a social, economic and environmental perspective. The industry has succeeded in terms of proven reserves, technology advancements, reduced operating costs, reliability and market accessibility. Some of the major challenges facing the industry include high capital cost, infrastructure, social services and keeping pace with growth. This presentation outlined the proactive measures that the oil sands industry has taken to manage environmental issues such as sulphur dioxide and nitrogen oxide emissions, greenhouse gases, water management and land reclamation. tabs., figs.

  17. Groundwater Discharges to Rivers in the Western Canadian Oil Sands Region

    Science.gov (United States)

    Ellis, J.; Jasechko, S.

    2016-12-01

    Groundwater discharges into rivers impacts the movement and fate of nutrients and contaminants in the environment. Understanding groundwater-surface water interactions is especially important in the western Canadian oil sands, where groundwater contamination risks are elevated and baseline water chemistry data is lacking, leading to substantial uncertainties about anthropogenic influences on local river quality. High salinity groundwater springs sourced from deep aquifers, comprised of Pleistocene-aged glacial meltwater, are known to discharge into many rivers in the oil sands. Understanding connections between deep aquifers and surficial waterways is important in order to determine natural inputs into these rivers and to assess the potential for injected wastewater or oil extraction fluids to enter surface waters. While these springs have been identified, their spatial distribution along rivers has not been fully characterized. Here we present river chemistry data collected along a number of major river corridors in the Canadian oil sands region. We show that saline groundwater springs vary spatially along the course of these rivers and tend to be concentrated where the rivers incise Devonian- or Cretaceous-aged aquifers along an evaporite dissolution front. Our results suggest that water sourced from Devonian aquifers may travel through bitumen-bearing Cretaceous units and discharge into local rivers, implying a strong groundwater-surface water connection in specialized locations. These findings indicate that oil sands process-affected waters that are injected at depth have the potential to move through these aquifers and reach the rivers at the surface at some time in the future. Groundwater-surface water interactions remain key to understanding the risks oil sands activities pose to aquatic ecosystems and downstream communities.

  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. Development, Parameterization, and Validation of a Visco-Plastic Material Model for Sand with DifferentLevels of Water Saturation

    Science.gov (United States)

    2009-01-01

    in essential physics of the tire –sand interactions. Towards that end, a simpler ribbed- tread tire model (described below) of the type often used for...i.e. the deflection and the contact area) on a rigid sur- face. The tire was modelled in the present work using a ribbed- tread tire model similar to...with material properties representing the composite behaviour through the carcass thick - ness. The tread -cap is constructed using linear, hybrid

  20. 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.

  1. Evaluation of Turf-Grass and Prairie-Vegetated Rain Gardens in a Clay and Sand Soil, Madison, Wisconsin, Water Years 2004-08

    Science.gov (United States)

    Selbig, William R.; Balster, Nicholas

    2010-01-01

    The U.S. Geological Survey, in cooperation with a consortium of 19 cities, towns, and villages in Dane County, Wis., undertook a study to compare the capability of rain gardens with different vegetative species and soil types to infiltrate stormwater runoff from the roof of an adjacent structure. Two rain gardens, one planted with turf grass and the other with native prairie species, were constructed side-by-side in 2003 at two locations with different dominant soil types, either sand or clay. Each rain garden was sized to a ratio of approximately 5:1 contributing area to receiving area and to a depth of 0.5 foot. Each rain garden, regardless of vegetation or soil type, was capable of storing and infiltrating most of the runoff over the 5-year study period. Both rain gardens in sand, as well as the prairie rain garden in clay, retained and infiltrated 100 percent of all precipitation and snowmelt events during water years 2004-07. The turf rain garden in clay occasionally had runoff exceed its confining boundaries, but was still able to retain 96 percent of all precipitation and snowmelt events during the same time period. Precipitation intensity and number of antecedent dry days were important variables that influenced when the storage capacity of underlying soils would become saturated, which resulted in pooled water in the rain gardens. Because the rooftop area that drained runoff to each rain garden was approximately five times larger than the area of the rain garden itself, evapotranspiration was a small percentage of the annual water budget. For example, during water year 2005, the maximum evapotranspiration of total influent volume ranged from 21 percent for the turf rain garden in clay to 25 percent for the turf rain garden in sand, and the minimum ranged from 12 percent for the prairie rain garden in clay to 19 percent for the prairie rain garden in sand. Little to no runoff left each rain garden as effluent and a small percentage of runoff returned to the

  2. Enhanced Column Filtration for Arsenic Removal from Water: Polymer-Templated Iron Oxide Nanoparticles Immobilized on Sand via Layer-by-Layer Deposition

    Science.gov (United States)

    Cheng, Calvin Chia-Hung

    Arsenic is ubiquitous in water sources around the world and is highly toxic. While precipitation and membrane filtration techniques are successfully implemented in developed cities, they are unsuitable for rural and low-resource settings lacking centralized facilities. This thesis presents the use of ultra-small iron oxide (Fe2O3) nanoparticles functionalized on sand granules for use as a house-hold scale adsorption filter. Water-stable alpha-Fe2O3 (hematite) nanoparticles (arsenic adsorption, with 147 +/- 2 mg As(III) per g Fe2O3 and 91 +/- 10 mg As(V) per g Fe2O3. The platform was also used to synthesize iron-based composites, including magnetite (Fe 3O4) and Fe-Cu oxide nanoparticles. For use as a column filter, Fe2O3-PAA nanoparticles were functionalized on sand granules using a layer-by-layer deposition method, with the nanoparticles embedded in the negative layer. The removal of As(III) by the Fe2O 3-PAA functionalized column was described by reversible 1st order kinetics where the forward and reverse rate constants were 0.31 hr -1 and 0.097 hr-1, respectively. Implemented as a passive water filter with 30 x 30 x 50 cm3 dimensions, the filter has an expected lifetime in the order of many years. By controlling the flow rate of the column depending on contamination levels, the filter effectively removes arsenic down to the safety limit of 0.01 mg/L. In a parallel project, the layer-by-layer deposition of Poly(diallydimethyl ammonium chloride) (PDDA) and poly(sodium 5-styrenesulfonate) (PSS) was exploited for a highly practical synthesis of discrete gradient surfaces. By independently controlling the concentration of NaCl in PDDA and PSS deposition solutions, a 2-dimensional matrix of surfaces was created in 96-well microtiter plates. Distinct non-monotonic dye adsorption patterns on the gradient surfaces was observed. Practical knowledge from this project was also used to enhance the nanoparticle surface functionalization described above. In all, a practical

  3. Pattern formation - Instabilities in sand ripples

    DEFF Research Database (Denmark)

    Hansen, J. L.; v. Hecke, M.; Haaning, A.

    2001-01-01

    Sand ripples are seen below shallow wavy water and are formed whenever water oscillates over a bed of sand. Here we analyse the instabilities that can upset this perfect patterning when the ripples are subjected to large changes in driving amplitude or frequency, causing them to deform both...

  4. Prevention of the growth of algae and protests in water treated with a calcinated sand; Ceramics seihin ni yoru suisochu no soruinado no hassei boshi

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, K.; Kakita, Y. [Fukuoka University, Fukuoka (Japan). Faculty of Pharmaceutical Science; Tanaka, A.; Yamasaki, K.; Masamoto, H.; Nakahara, S. [Fukuoka University, Fukuoka (Japan). Faculty of Engineering; Egashira, K. [Kyudenko Corp., Fukuoka (Japan)

    1995-07-10

    A commercial calcinated sand, Cleansand-205 (abbr. Kls-205 : a silica sand coated by a special procedure with a mixture of the oxides of Si, Al, Ti, and Ag), was tested for its ability to inhibit the growth of algae in a laboratory (batch-system) experiment. The growth of algae in water taken from a domestic gold fish basin was inhibited almost completely by about 5% (w/v) of Kls-205, under the conditions where fairly amounts of both nitrogen and phosphorus were present. However, Kls-205 (5%) showed little inhibition on algae which had already abundantly grown, and did not suppress further growth. The abilities of Kls-205 to adsorb nitrogen, phosphorus and carbon dioxide required for the growth and photosynthesis of algae were weak. The amounts of beta- and gamma-radiation and harmful heavy metal ions were the same levels as those from non-treated natural water. The dissolution of any antialgal substances and the generation of active oxygens were not observed. The possible role of Ag and/or its oxide with oligodynamie in inhibiting the growth of algae by Kls-205 was discussed. 15 refs., 4 figs., 2 tabs.

  5. Study on the water retention effect of compound soil of arsenic sandstone and sand under the condition of typical crop planting

    Science.gov (United States)

    Liu, S. Y.; Wang, N.; Xie, J. C.; Jiang, R. G.; Zhao, M. L.

    2017-08-01

    Arsenic sandstone is the main reason of soil erosion in the Mu Us Sandy Land, simultaneously was proved to be a kind of good water retaining agent. In order to provide references for the utilization of water and soil resources and the prevention and control of desertification and soil erosion of the southern margin of Mu Us Sandy Land, on the basis of earlier studies the farmland experiments of compound soil with three ratios of 1:1, 1:2 and 1:5 between arsenic sandstone and sand under maize planting patterns were designed, whose experimental process was divided into six stages according to the crop growth status. The results showed that the soil moisture content was highest in the layer of 0˜40cm where the compound soil mainly concentrated in, which was related to the potent water retention of arsenic sandstone and strong water permeability of undisturbed sandy soil. The variation coefficients in the soil of 1:1 and 1:2 were more stable and evenly distributed. The compound soil can effectively improve the soil water retention capacity, and prolong the storage time of soil water. Among them, water loss rate in soil of 1:1 and 1:2 were lower. The coefficient of variation also confirms that the water distributions of the two types of soil were more uniform and stable. Besides illustrating the effects of the soil amelioration measures on spatial and temporal variation of soil moisture content and the improvement of soil water regime, the study provides some references for the development and utilization of agriculture in Mu Us Sandy Land.

  6. Estimation of vanadium water quality benchmarks for the protection of aquatic life with relevance to the Athabasca Oil Sands region using species sensitivity distributions.

    Science.gov (United States)

    Schiffer, Stephanie; Liber, Karsten

    2017-11-01

    Elevated vanadium (V) concentrations in oil sands coke, which is produced and stored on site of some major Athabasca Oil Sands companies, could pose a risk to aquatic ecosystems in northern Alberta, Canada, depending on its future storage and utilization. In the present study, V toxicity was determined in reconstituted Athabasca River water to various freshwater organisms, including 2 midge species (Chironomus dilutus and Chironomus riparius; 4-d and 30-d to 40-d exposures) and 2 freshwater fish species (Oncorhynchus mykiss and Pimephales promelas; 4-d and 28-d exposures) to facilitate estimation of water quality benchmarks. The acute toxicity of V was 52.0 and 63.2 mg/L for C. dilutus and C. riparius, respectively, and 4.0 and 14.8 mg V/L for P. promelas and O. mykiss, respectively. Vanadium exposure significantly impaired adult emergence of C. dilutus and C. riparius at concentrations ≥16.7 (31.6% reduction) and 8.3 (18.0% reduction) mg/L, respectively. Chronic toxicity in fish presented as lethality, with chronic 28-d LC50s of 0.5 and 4.3 mg/L for P. promelas and O. mykiss, respectively. These data were combined with data from the peer-reviewed literature, and separate acute and chronic species sensitivity distributions (SSDs) were constructed. The acute and chronic hazardous concentrations endangering only 5% of species (HC5) were estimated as 0.64 and 0.05 mg V/L, respectively. These new data for V toxicity to aquatic organisms ensure that there are now adequate data available for regulatory agencies to develop appropriate water quality guidelines for use in the Athabasca Oil Sands region and elsewhere. Until then, the HC5 values presented in the present study could serve as interim benchmarks for the protection of aquatic life from exposure to hazardous levels of V in local aquatic environments. Environ Toxicol Chem 2017;36:3034-3044. © 2017 SETAC. © 2017 SETAC.

  7. Effect of manufactured sand on the durability characteristics of concrete

    Directory of Open Access Journals (Sweden)

    S. S. SARAVANAN

    2016-12-01

    Full Text Available Concrete is the most sought after material due to increase in construction activities and infrastructural developments. Availability of natural sand is decreasing thereby increase in the cost of construction. In the present work undertaken, an attempt has been made to give an alternative to natural sand. Optimization of replacement of natural sand with manufactured sand in concrete, durability studies such as water absorption, rapid chloride permeability test, sorptivity, acid resistance, alkaline resistance, impact resistance and abrasion resistance of M40 and M50 grades of concrete have been studied with manufactured sand as fine aggregate and compared the results with the conventional sand concrete. The results shows that there is an increase in the durability properties up to 70 % level of replacements of sand with manufactured sand as fine aggregate and for 100 % use of manufactured sand also gives the better durability than the conventional sand concrete.

  8. How well has biophysical research served the needs of water resource management? Lessons from the Sabie-Sand catchment

    CSIR Research Space (South Africa)

    Van Wyk, E

    2001-09-01

    Full Text Available frameworks proposed for integrated water resource management. The fundamental changes in the approach to water resource management warrant a critical evaluation of the information generated by past research and of the relevance of this activity and associated...

  9. 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.

  10. Serum biochemical reference intervals for free-living Sand Tiger sharks (Carcharias taurus) from east Australian waters.

    Science.gov (United States)

    Otway, Nicholas M

    2015-06-01

    Sharks are top-order predators in ocean food chains and the star attractions in aquaria worldwide. Unfortunately, blood biochemistry reference intervals (RI) have been determined for few species. The study aims to establish serum biochemical RI for free-living Sand Tiger sharks (Carcharias taurus) off eastern Australia. Thirty-seven sharks were captured and their sex, length, weight, reproductive maturity, and health status were recorded. After blood collection, serum analytes were quantified using standard analytical and statistical methods. Reference intervals, means, medians, and 90% confidence intervals were generated. Physiologic data from live and necropsied sharks were used to enhance the study results. Thirty healthy sharks were included in the study. Albumin could not be detected. With the exception of ALP activity, values were unaffected by sex, length, weight, age, and life-history stage. The means (RI) were: sodium 258 (249-267) mmol/L, potassium 5.0 (4.3-5.7) mmol/L, chloride 242 (227-257) mmol/L, inorganic phosphate 1.8 (1.7-2.0) mmol/L, total calcium 3.9 (3.3-4.4) mmol/L, magnesium 1.9 (1.6-2.2) mmol/L, glucose 2.7 (2.2-3.2) mmol/L, urea 377 (360-394) mmol/L, ALP 20 (8-31) U/L, ALT 3 U/L (no RI), AST 29 (13-45) U/L, CK 42 (5-79) U/L, total protein 30 (24-36) g/L, triglyceride 0.3 (0.1-0.6) mmol/L, cholesterol 1.4 (0.9-2.1) mmol/L, creatinine 32 μmol/L (no RI), total bilirubin 1.5 μmol/L (no RI), and osmolarity 1082 (1027-1136) mmol/L. These preliminary RI will assist with the clinical evaluation and treatment of captive and free-living Sand Tiger sharks worldwide. Studies with more animals will increase the precision of upper and lower reference limits. © 2015 American Society for Veterinary Clinical Pathology.

  11. Field Trial on Pea ( Pisum Sativum L.) Grown on Sand Soil and Subjected to Water Regimes and Nitrogen Forms with Aid of 15 N Stable Isotope

    International Nuclear Information System (INIS)

    Fahmy, A.E.; Abdel Aziz, H.A.; Al-Gindy, A.M.; Arafa, Y.E.

    2016-01-01

    A field experiment on sand soil was conducted to trace the effects of different water regimes on pea growth and nutritional values as fertilized with urea and ammonium sulfate fertilizers. 15 N/ 14 N isotope dilution technique was followed to distinguish between the different N proportions derived to pea plants and in the same time estimating the efficientuse of both two nitrogen forms (%NUE). Irrigation water regimes and fertilization treatments were applied under drip irrigation system. Two water regimes epresented 100% (W1) and 75% (W2) of water requirement in combination with three N fertilizer rates, i.e. N 0 , N 100 and N 75 were applied. Two nitrogen fertilizer forms represent urea and ammonium sulfate were performed. The overall means of seed yield as affected by nitrogen fertilization treatments reflected relative increase accounted for 45.8, and 38.7%; 41.7 and 36.2% over the unfertilized control for NU 100 , and NU 75 ; NAS 100 and NAS 75 , respectively. It seems that 100% water regime (W1) made nitrogen fertilizer, especially with high rate, more available for plant uptake comparing to the low water quantity regime. Pea crop had accumulated more nitrogen from urea comparing to ammonium sulfate fertilizer. Nitrogen uptake, in general, significantly correlated to application N rates. Water regime (W1) in combination with ammonium sulfate fertilizer resulted in the better percentage or absolute values of N derived from fertilizer by pea seeds. It was clear that efficient use of ammonium sulfate, to some extent, was affected by different wa - ter regimes. This holds true either at 100% (N1) or 75% (W2) application rates. On the other hand, urea added at rate of 75% was more efficiently used by seeds than those added at rate of 100% of the recommended N rate

  12. Disinfection of drain water of tomato by means of UV radiation and slow sand filtration in real greenhouse circumstances.

    Science.gov (United States)

    De Rocker, E; Goen, K; Van Poucke, K

    2006-01-01

    The efficiency of the disinfection of drain water was tested at 11 greenhouses with tomato cultivation on rockwool substrate in Flanders (Belgium) by means of mycological analysis. In addition the presence of phytopathogenic fungi in the drain water was analysed at 2 supplementary greenhouses with recirculation without disinfection.

  13. Immediate effect of simulated sand mining on the variation of bacterial parameters in coastal waters of Kalbadevi Bay, Ratnagiri

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, C.E.G.; Das, A.; Naik, S.S.; Sharma, R.; LokaBharathi, P.A.

    column at 1m and 3 m below surface water (bsf). Total abundance of bacteria (TC) in the water column ranged between 10 sup(6) cells.ml sup(-1) at 1 m and 10 sup(7) cells.ml sup(-1) at 3 mbsf before disturbance. It increased by 14% at input suction point...

  14. Experimental perforation of tubing with a hydraulic sand jet

    Energy Technology Data Exchange (ETDEWEB)

    Semenov, Yu V

    1970-01-01

    A series of field tests has shown that perforation with a hydraulic sand jet improves the quality of well completion. The sand jet does not crack the cement sheath or the casing, and the perforations are larger and deeper than perforations formed by explosive charges. Fluid circulation during sand jet perforation can safely be stopped for at least 10 min. Water containing a surfactant can be used as a sand carrier. Sand jet perforation allows successful completion of wells cased by 2 tubing strings. Sand jet perforation can be used to clean the borehole well and to remove foreign objects from the well.

  15. Evaluation of virus removal efficiency of coagulation-sedimentation and rapid sand filtration processes in a drinking water treatment plant in Bangkok, Thailand.

    Science.gov (United States)

    Asami, Tatsuya; Katayama, Hiroyuki; Torrey, Jason Robert; Visvanathan, Chettiyappan; Furumai, Hiroaki

    2016-09-15

    In order to properly assess and manage the risk of infection by enteric viruses in tap water, virus removal efficiency should be evaluated quantitatively for individual processes in actual drinking water treatment plants (DWTPs); however, there have been only a few studies due to technical difficulties in quantifying low virus concentration in water samples. In this study, the removal efficiency of indigenous viruses was evaluated for coagulation-sedimentation (CS) and rapid sand filtration (RSF) processes in a DWTP in Bangkok, Thailand by measuring the concentration of viruses before and after treatment processes using real-time polymerase chain reaction (qPCR). Water samples were collected and concentrated from raw source water, after CS, and after RSF, and inhibitory substances in water samples were reduced by use of a hydrophobic resin (DAX-8). Pepper mild mottle virus (PMMoV) and JC polyomavirus (JC PyV) were found to be highly prevalent in raw waters, with concentrations of 10(2.88 ± 0.35) and 10(3.06 ± 0.42) copies/L (geometric mean ± S.D.), respectively. Step-wise removal efficiencies were calculated for individual processes, with some variation observed between wet and dry seasons. During the wet season, PMMoV was removed less by CS and more by RSF on average (0.40 log10 vs 1.26 log10, respectively), while the reverse was true for JC PyV (1.91 log10 vs 0.49 log10, respectively). Both viruses were removed similarly during the dry season, with CS removing the most virus (PMMoV, 1.61 log10 and 0.78 log10; JC PyV, 1.70 log10, and 0.59 log10; CS and RSF, respectively). These differences between seasons were potentially due to variations in raw water quality and the characteristics of the viruses themselves. These results suggest that PMMoV and JC PyV, which are more prevalent in environmental waters than the other enteric viruses evaluated in this study, could be useful in determining viral fate for the risk management of viruses in water treatment

  16. Ostrich-Like Strategies in Sahelian Sands? Land and Water Grabbing in the Office du Niger, Mali

    Directory of Open Access Journals (Sweden)

    Thomas Hertzog

    2012-06-01

    Full Text Available In recent years, large-scale agricultural investment projects have increased in sub-Saharan Africa as a result of the growing appetites of local and international investors for land resources. Research has so far mainly focused on land issues, but the water implications of these land deals are starting to surface. Taking the Office du Niger (ON, in Mali, as a case study, we show that while around 100,000 ha is currently being cultivated, mostly by smallholders, a total of 600,000 ha of land has been allocated in the past ten years to investors in large-scale farming. This process has largely bypassed the official procedure established by the ON at regional level. The allocation of new lands has shifted to the national level, with an attempt to recentralize the management of land deals and associated benefits at the highest level, despite contrary efforts by foreign donors to strengthen the ON. This article describes the complex allocation process based on 'behind-closed-doors' negotiations. It then analyses the implications of the land deals on water issues by focusing on the strategies of actors to limit the risk of future water shortages, the current and expected difficulties in water management and allocation, and the emerging spatial and social redistribution of benefits and risk that signals a process of water grabbing.

  17. Predation and transport of persistent pathogens in GAC and slow sand filters: a threat to drinking water safety?

    Science.gov (United States)

    Bichai, Françoise; Dullemont, Yolanda; Hijnen, Wim; Barbeau, Benoit

    2014-11-01

    Zooplankton has been shown to transport internalized pathogens throughout engineered drinking water systems. In this study, experimental measurements from GAC and SSF filtration tests using high influent concentrations of Cryptosporidium (1.3 × 10(6) and 3.3 × 10(4) oocysts L(-1)) and Giardia (4.8 × 10(4) cysts L(-1)) are presented and compared. A predation and transport conceptual model was developed to extrapolate these results to environmental conditions of typical (oo)cyst concentrations in surface water in order to predict concentrations of internalized (oo)cysts in filtered water. Pilot test results were used to estimate transport and survival ratios of internalized (oo)cysts following predation by rotifers in the filter beds. Preliminary indications of lower transport and survival ratios in SSF were found as compared with GAC filters. A probability of infection due to internalized (oo)cysts in filtered water was calculated under likeliest environmental conditions and under a worst-case scenario. Estimated risks under the likeliest environmental scenario were found to fall below the tolerable risk target of 10(-4) infections per person per year. A discussion is presented on the health significance of persistent pathogens that are internalized by zooplankton during granular filtration processes and released into treated water. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. THE USE OF SILICA SAND, ZEOLITE AND ACTIVE CHARCOAL TO REDUCE BOD, COD AND TSS OF LAUNDRY WASTE WATER AS A BIOLOGY LEARNING RESOURCES

    Directory of Open Access Journals (Sweden)

    Moch Assiddieq

    2017-11-01

    Full Text Available The aquatic environment contaminated with detergent waste in high concentrations can endanger the lives human and biota in the water. This study aimed to determine the decrease of BOD, COD and TSS content of laundry liquid waste by using filter media of silica sand, zeolite, and activated charcoal. Filter medium 1a can reduce BOD level from 98.6 mg/L to 58.80 mg/L (40.36%, while medium 1b can decrease BOD level to 21.20 mg/L (78.48%. It showed that media 1a had not fulfilled the quality standard of BOD of waste water that is 50 mg/L, while media 1b had fulfilled the standard of quality. Filter media 1a can decrease COD level from 210 mg/L to 78.80 mg/L (62.47%, whereas medium 1b can decrease COD to 25.60 mg/L (87.80%. This showed that media 1a and media 1b had met the quality standard of COD of waste water that is 100 mg/L. Filter media 1a can decrease TSS level from 465 mg/L to 122.5 mg/L (73.65%, whereas medium 1b can decrease TSS level to 52.3 mg/L (88.75%. This showed that media 1a and media 1b had met the quality standard of TSS of waste water that is 150 mg/L.

  19. Hydrogeochemical processes affecting the migration of radionuclides in a fluvial sand aquifer at the Chalk River Nuclear Laboratories

    International Nuclear Information System (INIS)

    Jackson, R.E.; Inch, K.J.

    1980-01-01

    In the mid-1950's two experimental disposals of liquid radioactive waste containing about 700 curries of strontium-90 and cesium-137 were made into pits in sandy ground at one of the disposal areas at Chalk River Nuclear Laboratories. Since then, the wastes have migrated into two nearby aquifers and have chromatographically separated into strontium-90 and cesium-137 plumes moving at velocities less than that of the transporting groundwater. Analysis of radioactively contaminated aquifer sediments showed that most of the strontium-90 is exchangeably adsorbed, primarily to feldspars and layer silicates (mainly biotite); the rest is either specifically adsorbed to iron (III) and perhaps manganese (IV) oxhydroxides or fixed to unknown sinks. Less than one half of adsorbed cesium-137 is exchangeable with 0.5 m calcium chloride; the high levels of cesium-137 adsorption and fixation are probably due to its reaction with micaceous minerals. Complexation of strontium-90 and cesium-137 does not appear to be an important factor affecting their transport or adsorption. In studies of groundwater quality or pollution, dissolved oxygen and sulfide should be measured in addition to the redox potential since it allows independent assessment of the redox levels. The latter were found to affect the mobility of multivalent transition metals and nonmetals. (DN)

  20. Rheology of oil sands slurries

    Energy Technology Data Exchange (ETDEWEB)

    Chow, R.; Zhou, J. [Alberta Research Council, Edmonton, AB (Canada). Mineral Oil Sands Unit; Wallace, D. [Dean Wallace Consulting Inc., Beaumont, AB (Canada)

    2006-07-01

    This study focused on integrating rheology and colloid science to improve recovery of bitumen in surface mined oil sands. Factors that influence recovery, such as conditions of particle interaction, solids concentration and shear rate, were reviewed. In an effort to understand the rheological behaviour of clay-in-water suspensions, an elaborate procedure was developed to separate an inter-bedded clay layer from a site at Albian Sands Energy Inc. The variables were water chemistry, solids concentration, and shear rate. The research study was conducted at the Alberta Research Council with the support of the CONRAD Extraction Group. A controlled stress rheometer was used to provide the quantitative evaluations of the clay slurry properties. The research results indicate that the viscoelastic properties of the slurry are highly influenced by the shear history of the slurry, solids content, calcium concentration, and sample aging. Shear thinning behaviour was observed in all slurry samples, but the slurry viscosity increased with test time for a given shear rate. In order to classify the slurries, a method was developed to distinguish the gel strength. The slurries were then classified into 3 distinct patterns, including no gel, weak gel and strong gel. The evolution of the experimental protocols were described along with the current stability maps that correlate the domains of the gel strength according to the solids concentration, calcium ion content, and shear rate. It was concluded that the rheological properties of oil sands slurries influence bitumen recovery in commercial surface-mined oil sands operations. tabs., figs.

  1. Field test on sand compaction pile method with copper slag sand; Dosuisai slag wo mochiita SCP koho no shiken seko

    Energy Technology Data Exchange (ETDEWEB)

    Minami, K.; Matsui, H.; Naruse, E.; Kitazume, M. [Port and Harbour Research Inst., Kanagawa (Japan)

    1997-09-20

    This paper describes the sand compaction pile (SCP) method using copper slag sand. The SCP method is a method by which sand compaction piles are constructed in the ground, and improvement can be obtained in a short period. This method has been widely used even in the port areas for enhancing the bearing power of soft clay ground and the lateral resistance of sheet pile. A great deal of sand is required as a material. The sand requires high permeability, proper size distribution with less fine particle fraction content, easy compaction property with enough strength, and easy discharging property from the casing of construction machines as required properties. Recently, it becomes hard to secure proper sand materials. The copper slag sand is obtained from refining process of copper as a by-product which is quenched in water flow and crushed in water. The copper slag sand has higher particle density than that of sand, excellent permeability, and similar size distribution to that of sand. From compaction drainage triaxial compression test and permeability test, it was found that the mechanical properties of copper slag sand did not change by the crushing of grains with keeping excellent permeability. Through the test construction, applicability of the copper slag sand to the SCP method could be confirmed as an alternate material of sand. 17 refs., 9 figs., 4 tabs.

  2. Sun, Sand and Water: A History of the Jacksonville District U.S. Army Corps of Engineers 1821-1975

    Science.gov (United States)

    1981-01-01

    centuries-old ecological balance which had been developed in nature was not understood, considered, or known by those early pioneers who envisioned tap...could only see that "water will run down hill," brought ecological disasters to south Florida; the Jacksonville District Engineers, studying the...guided by the experienced man on the job. Starrett Brothers also shifted to prefabrication to aid construction. They set up plans for building

  3. Sand, jams and jets

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, H. [James Franck Institute and Department of Physics, University of Chicago (United States)]. E-mail: h-jaeger@uchicago.edu

    2005-12-01

    Granular media are offering new insights into problems in condensed-matter physics and materials science, as Heinrich Jaeger explains. The remarkable properties of granular materials are so familiar that most of us do not even notice them. It is clear, for example, that we cannot walk on water unless the temperature has dropped below freezing. However, we take it for granted that sand will support our weight as if it were a solid, even though it can also be poured like a liquid under the same ambient conditions. From breakfast cereal, sugar and flour to construction materials, mining products and pharmaceuticals, granular media are present everywhere in our daily lives. (U.K.)

  4. Hydrogeology and water quality of sand and gravel aquifers in McHenry County, Illinois, 2009-14, and comparison to conditions in 1979

    Science.gov (United States)

    Gahala, Amy M.

    2017-10-26

    Baseline conditions for the sand and gravel aquifers (groundwater) in McHenry County, Illinois, were assessed using data from a countywide network of 44 monitoring wells collecting continuous water-level data from 2009–14. In 2010, water-quality data were collected from 41 of the monitoring wells, along with five additional monitoring wells available from the U.S. Geological Survey National Water Quality Assessment Program. Periodic water-quality data were collected from 2010–14 from selected monitoring wells. The continuous water-level data were used to identify the natural and anthropogenic factors that influenced the water levels at each well. The water-level responses to natural influences such as precipitation, seasonal and annual variations, barometric pressure, and geology, and to anthropogenic influences such as pumping were used to determine (1) likely hydrogeologic setting (degree of aquifer confinement and interconnections) that, in part, are related to lithostratigraphy; and (2) areas of recharge and discharge related to vertical flow directions. Water-level trends generally were determined from the 6 years of data collection (2009–14) to infer effects of weather variability (drought) on recharge.Precipitation adds an estimated 2.4 inches per year of recharge to the aquifer. Some of this recharge is subsequently discharged to streams and some is discharged to supply wells. A few areas in the eastern half of the county had higher average recharge rates, indicating a need for adequate protection of these recharge areas. Downward vertical flow gradients in upland areas indicate that recharge to the confined aquifer units occurs near upland areas. Upward vertical flow gradients in lowland areas indicate discharge at locations of surface water and groundwater interaction (wetlands, ponds, and streams).Monitoring wells were sampled for major and minor ions, metals, and nutrients and a subset of wells was sampled for trace elements, dissolved gases

  5. Experimental investigation of sanding propensity for the Andrew completion

    Energy Technology Data Exchange (ETDEWEB)

    Venkitaraman, A.; Li, H. [Schlumberger Perforating and Testing Center (United Kingdom); Leonard, A. J.; Bowden, P. R. [BP Exploration (United Kingdom)

    1998-12-31

    A series of laboratory experiments were performed on three reservoir core samples selected from two plot wells to confirm the likelihood of sand production during the completion phase of the planned Andrew horizontal wells, and to perform risk analysis of formation failure at the time of underbalance perforation, and expected producing conditions. CT scans revealed no perforation failure, and the core samples did not show any propensity to produce sand during single-phase oil flow. Transient sand production was observed when water cut was introduced, but sand production declined as the percentage of water cut was increased. There was no evidence of sand production in the core samples during depletion testing either, and the wells were subsequently completed with perforated cemented liners without sand control. No sand problems have been encountered in two years of production, with some wells in water cut and declined reservoir pressure of 200 psi. 8 refs., 3 tabs., 5 figs.

  6. 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...

  7. Processes Affecting Agricultural Drainwater Quality and Organic Carbon Loads in California's Sacramento–San Joaquin Delta

    Directory of Open Access Journals (Sweden)

    Steven J. Deverel

    2007-05-01

    Full Text Available From 2000 to 2003 we quantified drain flow, drain-and ground-water chemistry and hydrogeologic conditions on Twitchell Island in the Sacramento-San Joaquin Delta. The primary objective was to quantify processes affecting organic carbon concentrations and loads in agricultural drainage water. We collected physical and chemical data in southern and northern areas: TN and TS, respectively. Corn grew in both areas during the spring and summer. The peat soils in the TN area are more decomposed than those in the TS area. Results elucidate processes affecting drain flow and concentrations under varying hydrologic conditions. During May through November, groundwater flows from the permanently saturated zone to drainage ditches, and the resulting average drainage-water quality and dissolved organic carbon (DOC concentration was similar to the groundwater; the median DOC loads in the TN and TS study areas ranged from 9 to 27 g C/ha-day. The major ion chemistry and stable isotope data confirmed that groundwater was the primary source of drainflow. In contrast, during December through April the drainwater is supplied from the shallow, variably saturated soil-zone. The DOC concentrations, major-ion chemistry, and stable isotope data indicate that the shallow-zone water is partially evaporated and oxidized. Higher flows and DOC concentrations during these months result in higher median DOC loads, which ranged from 84 to 280 g C/ha-day. During December through April, increasing groundwater levels in the shallow peat layers and mobilization of organic carbon result in high drain flow and increased trihalomethane precursor concentrations and loads. On a per mass DOC basis, drain water collected during high flow periods is less likely to form THMs than during low flow periods. However, the high flows and subsequent high concentrations contribute to substantially higher trihalomethane precursor and DOC loads.

  8. Sensitivity analysis on parameters and processes affecting vapor intrusion risk

    KAUST Repository

    Picone, Sara; Valstar, Johan; van Gaans, Pauline; Grotenhuis, Tim; Rijnaarts, Huub

    2012-01-01

    the ventilated crawl space of a house. In contrast to the vast majority of previous studies, this model accounts for vertical variation of soil water saturation and includes aerobic biodegradation. The attenuation factor (ratio between concentration in the crawl

  9. Compressive strength and initial water absorption rate for cement brick containing high-density polyethylene (HDPE) as a substitutional material for sand

    Science.gov (United States)

    Ali, Noorwirdawati; Din, Norhasmiza; Sheikh Khalid, Faisal; Shahidan, Shahiron; Radziah Abdullah, Siti; Samad, Abdul Aziz Abdul; Mohamad, Noridah

    2017-11-01

    The rapid growth of today’s construction sector requires high amount of building materials. Bricks, known to have solid properties and easy to handle, which leads to the variety of materials added or replaced in its mixture. In this study, high density polyethylene (HDPE) was selected as the substitute materials in the making of bricks. The reason behind the use of HDPE is because of its recyclable properties and the recycling process that do not emit hazardous gases to the atmosphere. Other than that, the use of HDPE will help reducing the source of pollution by avoiding the millions of accumulated plastic waste in the disposal sites. Furthermore, the material has high endurance level and is weatherproof. This study was carried out on experimenting the substitute materials in the mixture of cement bricks, a component of building materials which is normally manufactured using the mixture of cement, sand and water, following a certain ratios, and left dried to produce blocks of bricks. A series of three different percentages of HDPE were used, which were 2.5%, 3.0% and 3.5%. Tests were done on the bricks, to study its compressive strength and the initial water absorption rate. Both tests were conducted on the seventh and 28th day. Based on the results acquired, for compressive strength tests on the 28th day, the use of 2.5% of HDPE shown values of 12.6 N/mm2 while the use of 3.0% of HDPE shown values of 12.5 N/mm2. Onto the next percentage, 3.5% of HDPE shown values of 12.5 N/mm2.

  10. Developing and Applying Control Charts to Detect Change Water Chemistry Parameters Measured in the Athabasca River Near the Oil Sands: A Tool for Surveillance Monitoring.

    Science.gov (United States)

    Arciszewski, Tim J; Hazewinkel, Rod R; Munkittrick, Kelly R; Kilgour, Bruce W

    2018-05-10

    Control charting is a simple technique to identify change and is well-suited for use in water quality programs. Control charts accounting for co-variation associated with discharge and time were used to explore example and representative variables routinely measured in the Athabasca River near the oil sands area for indications of change, including 5 major ions (chloride, sodium, sulphate, calcium, magnesium), 5 total metals (aluminum, iron, thallium, molybdenum, vanadium) and total suspended solids (TSS). Regression equations developed from reference data (1988-2009) were used to predict observations and calculate residuals from later test observations (2010-2016). Evidence of change was sought in the deviation of residual errors from the test period compared to the patterns expected and defined from probability distributions of the reference residuals using the Odds Ratio. In most cases, the patterns in test residuals were not statistically different from those expected from the reference period, especially when data was examined annually. However, some differences were apparent and more differences were apparent as data accumulated and was analysed over time. In sum, the analyses suggest higher concentrations than predicted in most major ions, but the source of the changes is uncertain. In contrast, most metals were lower than expected and may be related to changing deposition patterns of materials or weathering of minerals during construction activities of the 2000's which influence the reference data used. The analyses also suggest alternative approaches may be necessary to understand change in some variables. Despite this, the results support the use of control charts to detect changes in water chemistry parameters and the value of the tool in surveillance phases of long-term and adaptive monitoring programs. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  11. Occurrence of Escherichia coli and Enterococci in Cladophora (Chlorophyta) in Nearshore Water and Beach Sand of Lake Michigan†

    Science.gov (United States)

    Whitman, Richard L.; Shively, Dawn A.; Pawlik, Heather; Nevers, Meredith B.; Byappanahalli, Muruleedhara N.

    2003-01-01

    Each summer, the nuisance green alga Cladophora (mostly Cladophora glomerata) amasses along Lake Michigan beaches, creating nearshore anoxia and unsightly, malodorous mats that can attract problem animals and detract from visitor enjoyment. Traditionally, elevated counts of Escherichia coli are presumed to indicate the presence of sewage, mostly derived from nearby point sources. The relationship between fecal indicator bacteria and Cladophora remains essentially unstudied. This investigation describes the local and regional density of Escherichia coli and enterococci in Cladophora mats along beaches in the four states (Wisconsin, Illinois, Indiana, and Michigan) bordering Lake Michigan. Samples of Cladophora strands collected from 10 beaches (n = 41) were assayed for concentrations of E. coli and enterococci during the summer of 2002. Both E. coli and enterococci were ubiquitous (up to 97% occurrence), with overall log mean densities (± standard errors) of 5.3 (± 4.8) and 4.8 (± 4.5) per g (dry weight). E. coli and enterococci were strongly correlated in southern Lake Michigan beaches (P Cladophora mats stored at 4°C; the residual bacteria in the dried alga readily grew upon rehydration. These findings suggest that Cladophora amassing along the beaches of Lake Michigan may be an important environmental source of indicator bacteria and call into question the reliability of E. coli and enterococci as indicators of water quality for freshwater recreational beaches. PMID:12902262

  12. Occurrence of Escherichia coli and enterococci in Cladophora (Chlorophyta) in nearshore water and beach sand of Lake Michigan.

    Science.gov (United States)

    Whitman, Richard L; Shively, Dawn A; Pawlik, Heather; Nevers, Meredith B; Byappanahalli, Muruleedhara N

    2003-08-01

    Each summer, the nuisance green alga Cladophora (mostly Cladophora glomerata) amasses along Lake Michigan beaches, creating nearshore anoxia and unsightly, malodorous mats that can attract problem animals and detract from visitor enjoyment. Traditionally, elevated counts of Escherichia coli are presumed to indicate the presence of sewage, mostly derived from nearby point sources. The relationship between fecal indicator bacteria and Cladophora remains essentially unstudied. This investigation describes the local and regional density of Escherichia coli and enterococci in Cladophora mats along beaches in the four states (Wisconsin, Illinois, Indiana, and Michigan) bordering Lake Michigan. Samples of Cladophora strands collected from 10 beaches (n = 41) were assayed for concentrations of E. coli and enterococci during the summer of 2002. Both E. coli and enterococci were ubiquitous (up to 97% occurrence), with overall log mean densities (+/- standard errors) of 5.3 (+/- 4.8) and 4.8 (+/- 4.5) per g (dry weight). E. coli and enterococci were strongly correlated in southern Lake Michigan beaches (P Cladophora mats stored at 4 degrees C; the residual bacteria in the dried alga readily grew upon rehydration. These findings suggest that Cladophora amassing along the beaches of Lake Michigan may be an important environmental source of indicator bacteria and call into question the reliability of E. coli and enterococci as indicators of water quality for freshwater recreational beaches.

  13. Occurrence of Escherichia coli and enterococci in Cladophora (Clorophyta) in nearshore water and beach sand of Lake Michigan

    Science.gov (United States)

    Whitman, Richard L.; Shively, Dawn A.; Pawlik, Heather; Nevers, Meredith B.; Byappanahalli, Muruleedhara N.

    2003-01-01

    Each summer, the nuisance green alga Cladophora (mostly Cladophora glomerata) amasses along Lake Michigan beaches, creating nearshore anoxia and unsightly, malodorous mats that can attract problem animals and detract from visitor enjoyment. Traditionally, elevated counts of Escherichia coli are presumed to indicate the presence of sewage, mostly derived from nearby point sources. The relationship between fecal indicator bacteria and Cladophora remains essentially unstudied. This investigation describes the local and regional density of Escherichia coli and enterococci in Cladophora mats along beaches in the four states (Wisconsin, Illinois, Indiana, and Michigan) bordering Lake Michigan. Samples of Cladophora strands collected from 10 beaches (n = 41) were assayed for concentrations of E. coli and enterococci during the summer of 2002. Both E. coli and enterococci were ubiquitous (up to 97% occurrence), with overall log mean densities (± standard errors) of 5.3 (± 4.8) and 4.8 (± 4.5) per g (dry weight). E. coli and enterococci were strongly correlated in southern Lake Michigan beaches (P R2 = 0.73, n = 17) but not in northern beaches (P = 0.892, n = 16). Both E. coli and enterococci survived for over 6 months in sun-dried Cladophora mats stored at 4°C; the residual bacteria in the dried alga readily grew upon rehydration. These findings suggest that Cladophora amassing along the beaches of Lake Michigan may be an important environmental source of indicator bacteria and call into question the reliability of E. coli and enterococci as indicators of water quality for freshwater recreational beaches.

  14. 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.

  15. Geotechnical properties of crude oil contaminated sand

    International Nuclear Information System (INIS)

    Puri, V.K.; Das, B.M.; Cook, E.E.; Shin, E.C.

    1994-01-01

    Contamination of soil due to an oil spill influences its subsequent engineering behavior. An investigation was conducted to study the effect of crude oil contamination on compaction characteristics, shear strength, one-dimensional compression, and coefficient of permeability. Water permeability was also determined by using commercial grade motor oils as contaminants. The test results indicate that the compaction characteristics are influenced by oil contamination. The angle of internal friction of sand (based on total stress condition) decreases due to presence of oil within the pore spaces in sand. One dimensional compression characteristics of sand are significantly influenced by oil contamination resulting in a decrease in the value of constrained modulus with increase in the degree of oil contamination compared to the case of dry sand. Water permeability was observed to be a function of the initial viscosity and the degree of saturation due to the contaminating oil

  16. Sensitivity analysis on parameters and processes affecting vapor intrusion risk

    KAUST Repository

    Picone, Sara

    2012-03-30

    A one-dimensional numerical model was developed and used to identify the key processes controlling vapor intrusion risks by means of a sensitivity analysis. The model simulates the fate of a dissolved volatile organic compound present below the ventilated crawl space of a house. In contrast to the vast majority of previous studies, this model accounts for vertical variation of soil water saturation and includes aerobic biodegradation. The attenuation factor (ratio between concentration in the crawl space and source concentration) and the characteristic time to approach maximum concentrations were calculated and compared for a variety of scenarios. These concepts allow an understanding of controlling mechanisms and aid in the identification of critical parameters to be collected for field situations. The relative distance of the source to the nearest gas-filled pores of the unsaturated zone is the most critical parameter because diffusive contaminant transport is significantly slower in water-filled pores than in gas-filled pores. Therefore, attenuation factors decrease and characteristic times increase with increasing relative distance of the contaminant dissolved source to the nearest gas diffusion front. Aerobic biodegradation may decrease the attenuation factor by up to three orders of magnitude. Moreover, the occurrence of water table oscillations is of importance. Dynamic processes leading to a retreating water table increase the attenuation factor by two orders of magnitude because of the enhanced gas phase diffusion. © 2012 SETAC.

  17. 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.

  18. Technetium, Iodine, and Chromium Adsorption/Desorption Kd Values for Vadose Zone Pore Water, ILAW Glass, and Cast Stone Leachates Contacting an IDF Sand Sequence

    Energy Technology Data Exchange (ETDEWEB)

    Last, George V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Snyder, Michelle M.V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Um, Wooyong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stephenson, John R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Leavy, Ian I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Strickland, Christopher E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bacon, Diana H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Qafoku, Nikolla [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Serne, R. Jeffrey [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-11-01

    Performance and risk assessments of immobilized low-activity waste (ILAW) at the Integrated Disposal Facility (IDF) have shown that risks to groundwater are quite sensitive to adsorption-desorption interactions occurring in the near- and far-field environment. These interactions between the underlying sediments and the contaminants present in the leachates that descend from the buried glass, secondary waste grouts, and potentially Cast Stone low-activity waste packages have been represented in these assessments using the contaminant distribution coefficient (Kd) construct. Some contaminants (99Tc, 129I, and Cr) present in significant quantities in these wastes have low Kd values and tend to drive risk to public health and the environment. Relatively small changes in the Kd value can cause relatively large changes in the retardation factor. Thus, even relatively small uncertainty in the Kd value can result in a relatively large uncertainty in the risk determined through performance assessment modeling. The purpose of this study is to further reduce the uncertainty in Kd values for 99Tc, iodine (iodide and iodate), and Cr (chromate; CrO42-) by conducting systematic adsorption-desorption experiments using actual sand-dominated Hanford formation sediments from beneath the IDF and solutions that closely mimic Hanford vadose zone pore water and leachates from Cast Stone and ILAW glass waste forms. Twenty-four batch and 21 flow-through column experiments were conducted, yielding 261 Kd measurements for these key contaminants, and contributing to our understanding for predicting transport from wastes disposed to the IDF. While the batch Kd methodology is not well-suited for measuring Kd values for non-sorbing species (as noted by the U.S. Environmental Protection Agency), the batch Kd results presented here are not wholly inconsistent with the column Kd results, and could be used for sensitivity purposes. Results from the column experiments are consistent with the best

  19. Effects of different pretreatments on the performance of ceramic ultrafiltration membrane during the treatment of oil sands tailings pond recycle water: a pilot-scale study.

    Science.gov (United States)

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

    2015-03-15

    Membrane filtration is an effective treatment method for oil sands tailings pond recycle water (RCW); however, membrane fouling and rapid decrease in permeate flux caused by colloids, organic matter, and bitumen residues present in the RCW hinder its successful application. This pilot-scale study investigated the impact of different pretreatment steps on the performance of a ceramic ultrafiltration (CUF) membrane used for the treatment of RCW. Two treatment trains were examined: treatment train 1 consisted of coagulant followed by a CUF system, while treatment train 2 included softening (Multiflo™ system) and coagulant addition, followed by a CUF system. The results indicated that minimum pretreatment (train 1) was required for almost complete solids removal. The addition of a softening step (train 2) provided an additional barrier to membrane fouling by reducing hardness-causing ions to negligible levels. More than 99% removal of turbidity and less than 20% removal of total organic carbon were achieved regardless of the treatment train used. Permeate fluxes normalized at 20 °C of 127-130 L/m(2) h and 111-118 L/m(2) h, with permeate recoveries of 90-93% and 90-94% were observed for the treatment trains 1 and 2, respectively. It was also found that materials deposited onto the membrane surface had an impact on trans-membrane pressure and influenced the required frequencies of chemically enhanced backwashes (CEBs) and clean-in-place (CIP) procedures. The CIP performed was successful in removing fouling and scaling materials such that the CUF performance was restored to baseline levels. The results also demonstrated that due to their low turbidity and silt density index values, permeates produced in this pilot study were suitable for further treatment by high pressure membrane processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Singing Sand Dunes

    Indian Academy of Sciences (India)

    ble low-frequency (s. 75–105 Hz), that can some- times be heard up to 10 km away. Scientific in- vestigations suggest that the sustained low fre- quency sound of sand dunes that resembles a pure note from a musical instrument, is due to the synchronized motion of well-sorted dry sand grains when they spontaneously ...

  1. Biosphere processes affecting environmnetal impacts of hazardous wastes

    International Nuclear Information System (INIS)

    Watkins, B.; Broderick, M.

    1991-01-01

    ANS Consultants Limited has reviewed and assessed a number of biosphere processes which affect the environmental impact of hazardous waste disposal. Processes examined have included the long-term effects of climate change on biosphere characteristics and the transport of toxic materials in food chains; the role of soil animals and plants roots in cycling elements from depth to the soil surface; volatisation mechanisms; the transport of elements in soil with particular reference to erosion and resuspension; mechanisms for foliar contamination via irrigation waters; and organic matter decomposition in varying environmental conditions. (au)

  2. 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...

  3. Afyon-Sandıklı

    Indian Academy of Sciences (India)

    δ18O and δD isotope ratios of the Sandıklı waters plot along the continental meteoric water line ... and district heating. Several studies on geology, hydrogeology along ..... precipitation; In: Handbook of Environmental Isotope. Geochemistry ...

  4. Evaluate of head loss, sediment value and copper removal in sand media (rapid sand filter

    Directory of Open Access Journals (Sweden)

    Daneshi Navab

    2014-06-01

    Full Text Available Along with the technology development and increasing consumption of water resources, we are experiencing low qualities in the mentioned resources. Copper brings about serious environment al pollution, threatening human health and ecosystem. This metal found variously in water resources and industrial activities. Therefore, it needs to treat the water resources from these excessive amounts. Different methods have used for this reason but the most used method during recent years has been the absorption by economic absorbers such as sand. Rapid sand filters usually used in water and wastewater treatment plants for water clarification. In this research, a single layer gravity rapid sand filter has used to reduce different concentrations of copper. sediment value and head loss arising in filter media is simulated by using combination of Carman-Kozeny, Rose and Gregory models in different discharges of rapid sand filter. Results have shown that with increasing in discharge and decreasing in input copper concentration, arriving time to given head loss, is increasing. In addition, results demonstrated that with increasing in copper concentration in influent, removal efficiency is decreasing somewhat. Results of this research can applied in an appropriate design of rapid sand filter to copper removal, a prediction of rapid sand filter ability to copper removal and an estimation of arising head loss during filter work thus evaluating of time interval backwash. DOI: http://dx.doi.org/10.3126/ije.v3i2.10641 International Journal of the Environment Vol.3(2 2014: 276-286

  5. 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.

  6. Distribution of radioactive "1"3"7Cs and "1"3"4Cs in river water and bottom sand for major rivers at Minami-Soma City in Fukushima

    International Nuclear Information System (INIS)

    Kajimoto, Tsuyoshi; Endo, Satoru; Shizuma, Kiyoshi; Naganuma, Takeshi

    2012-01-01

    A nuclear power plant accident, which occurred on March 11, 2011, caused severe radioactive contamination in Fukushima. We initiated an environmental radioactive survey in Minami-Soma City the following October. The city is located approximately 10-40 km north of the TEPCO's Fukushima Daiichi Nuclear Power Plant. The study reported here involves an environmental radioactive survey conducted along three rivers and their tributary streams.Water and bottom sands were collected from four to six sampling locations along each river. Water samples (1 L) were dried on thin Teflon sheets, and gamma-ray measurements were performed with a well-type Ge detector. Sand samples were homogenized after drying, and approximately 50 g were measured for gamma-rays with a low-background coaxial-type Ge detector. The Cs concentrations ("1"3"7Cs+"1"3"4Cs) were determined to be 10,000-20,000 Bq/kg in the bottom sand collected from the upper reaches of the rivers, whereas the concentrations measured from samples collected near coastal down reaches were measured at about 200 Bq/kg. The Cs concentrations measured in river water were about 0.8 Bq/L in the upper reaches of the rivers and 0.3 Bq/L in the lower reaches, indicating that the Cs concentration in water is quite low. It is necessary to study the behavior of the contaminants in the upper reaches of the river system, and determine if they will move to the down stream area hereafter. (author)

  7. Distribution of radioactive "1"3"7Cs and "1"3"4Cs in river water and bottom sand for major rivers at Minami-Soma City in Fukushima

    International Nuclear Information System (INIS)

    Kajimoto, Tsuyoshi; Endo, Satoru; Shizuma, Kiyoshi; Naganuma, Takeshi

    2013-01-01

    A nuclear power plant accident, which occurred on March 11, 2011, caused severe radioactive contamination in Fukushima. We initiated an environmental radioactive survey in Minami-Soma City the following October. The city is located approximately 10-40 km north of the TEPCO's Fukushima Daiichi Nuclear Power Plant. The study reported here involves an environmental radioactive survey conducted along three rivers and their tributary streams. Water and bottom sands were collected from four to six sampling locations along each river. Water samples (1 L) were dried on thin Teflon sheets, and gamma-ray measurements were performed with a well-type Ge detector. Sand samples were homogenized after drying, and approximately 50 g were measured for gamma-rays with a low-background coaxial-type Ge detector. The Cs concentrations ("1"3"7Cs+"1"3"4Cs) were determined to be 10,000-20,000 Bq/kg in the bottom sand collected from the upper reaches of the rivers, whereas the concentrations measured from samples collected near coastal down reaches were measured at about 200 Bq/kg. The Cs concentrations measured in river water were about 0.8 Bq/L in the upper reaches of the rivers and 0.3 Bq/L in the lower reaches, indicating that the Cs concentration in water is quite low. It is necessary to study the behavior of the contaminants in the upper reaches of the river system, and determine if they will move to the down stream area hereafter. (author)

  8. Sand and Gravel Deposits

    Data.gov (United States)

    Vermont Center for Geographic Information — This dataset is a statewide polygon coverage of sand, gravel, and stone resources. This database includes the best data available from the VT Agency of Natural...

  9. Sand and Gravel Operations

    Data.gov (United States)

    Department of Homeland Security — This map layer includes sand and gravel operations in the United States. These data were obtained from information reported voluntarily to the USGS by the aggregate...

  10. Separated by sand, fused by dropping water: habitat barriers and fluctuating water levels steer the evolution of rock-dwelling cichlid populations in Lake Tanganyika.

    Science.gov (United States)

    Koblmüller, Stephan; Salzburger, Walter; Obermüller, Beate; Eigner, Eva; Sturmbauer, Christian; Sefc, Kristina M

    2011-06-01

    The conditions of phenotypic and genetic population differentiation allow inferences about the evolution, preservation and loss of biological diversity. In Lake Tanganyika, water level fluctuations are assumed to have had a major impact on the evolution of stenotopic littoral species, though this hypothesis has not been specifically examined so far. The present study investigates whether subtly differentiated colour patterns of adjacent Tropheus moorii populations are maintained in isolation or in the face of continuous gene flow, and whether the presumed influence of water level fluctuations on lacustrine cichlids can be demonstrated in the small-scale population structure of the strictly stenotopic, littoral Tropheus. Distinct population differentiation was found even across short geographic distances and minor habitat barriers. Population splitting chronology and demographic histories comply with our expectation of old and rather stable populations on steeper sloping shore, and more recently established populations in a shallower region. Moreover, population expansions seem to coincide with lake level rises in the wake of Late Pleistocene megadroughts ~100 KYA. The imprint of hydrologic events on current population structure in the absence of ongoing gene flow suggests that phenotypic differentiation among proximate Tropheus populations evolves and persists in genetic isolation. Sporadic gene flow is effected by lake level fluctuations following climate changes and controlled by the persistence of habitat barriers during lake level changes. Since similar demographic patterns were previously reported for Lake Malawi cichlids, our data furthermore strengthen the hypothesis that major climatic events synchronized facets of cichlid evolution across the East African Great Lakes. © 2011 Blackwell Publishing Ltd.

  11. 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.)

  12. MECHANICAL REGENERATION OF SAND WASTE

    Directory of Open Access Journals (Sweden)

    D. I. Gnir

    2005-01-01

    Full Text Available The experimental activation of the sand regenerator of the firm SINTO is carried out at ОАО “MZOO". It is shown that sand grains are cleared from films of binding agents, that allows to use the treated sand for preparation of agglutinant and core sands.

  13. Reuse of waste cutting sand at Lawrence Livermore National Laboratory

    International Nuclear Information System (INIS)

    Mathews, S.; Wilson, K.

    1998-01-01

    Lawrence Livermore National Laboratory (LLNL) examined the waste stream from a water jet cutting operation, to evaluate the possible reuse of waste garnet sand. The sand is a cutting agent used to shape a variety of materials, including metals. Nearly 70,000 pounds of waste sand is generated annually by the cutting operation. The Environmental Protection Department evaluated two potential reuses for the spent garnet sand: backfill in utility trenches; and as a concrete constituent. In both applications, garnet waste would replace the sand formerly purchased by LLNL for these purposes. Findings supported the reuse of waste garnet sand in concrete, but disqualified its proposed application as trench backfill. Waste sand stabilized in a concrete matrix appeared to present no metals-leaching hazard; however, unconsolidated sand in trenches could potentially leach metals in concentrations high enough to threaten ground water quality. A technical report submitted to the San Francisco Bay Regional Water Quality Control Board was reviewed and accepted by that body. Reuse of waste garnet cutting sand as a constituent in concrete poured to form walkways and patios at LLNL was approved

  14. U-series in Fe(III)-U(VI) rich fracture infill-materials from the oxidised cap of the U-ore deposit of Mina Fe (Salamanca, Spain): Implications for water/rock interaction processes affecting and analogue site (Matrix II project)

    International Nuclear Information System (INIS)

    Perez del Villar, L.; Grespo, M. T.; Quejido, A. J.

    2002-01-01

    In the frame of the ENRESA natural analogue programme. The U-ore deposit of Mina Fe being studied as a natural analogue of radioactive spent fuel behaviour. In this context the knowledge of the role played by fracture minerals as scavengers of certain analogue elements. Mainly U, and the establishment of the time scale of the rock-water interaction processes controlling the uptakes or losses of U in the system are two relevant objectives

  15. Filamentous fungi isolated from sand and water of "Bairro Novo" and "Casa Caiada" beaches, Olinda, Pernambuco, Brazil Fungos filamentosos isolados do solo e da água nas praias de Bairro Novo e Casa Caiada, Olinda, Pernambuco, Brasil

    Directory of Open Access Journals (Sweden)

    DNF. Gomes

    2008-08-01

    Full Text Available Fungi comprehend a heterogeneous group of heterotrophic microorganisms that act as saprobes or parasites or, less frequently, as symbionts living in association with other organisms. They are cosmopolitan and important components of ecosystems. Considering the small number of Brazilian papers on the filamentous mycota in marine environments, and the need to improve knowledge of the diversity of these microfungi in "Casa Caiada" and "Bairro Novo" beaches, Olinda, PE, the aim of this work was to isolate and identify the fungi from sand and water samples of these ecosystems. Thirty two samplings of sand (surface and 20 cm deep and water (surface and 1 m deep were carried out during the dry and rainy seasons, in low and high tide. From each sand sample, a suspension was made with 50 g of sand diluted in 90 mL of sterilized distilled water. From each sand suspension and water sample, 0.5 mL was spread, in triplicate, onto Petri dishes containing Sabouraud Agar added of chloramphenicol. The plates were incubated at 28 °C (±2 °C. Fifty seven species were isolated, identified, and classified in 20 genera. Aspergillus and Penicillium were the most frequent genera in both sand and water, with a total of 11 and 19 species, respectively.Os fungos compreendem um grupo heterogêneo de microorganismos heterotróficos, atuando como sapróbios ou parasitas, ou menos freqüentemente como simbiontes, vivendo em associação com outros organismos. São cosmopolitas e componentes importantes dos ecossistemas. Considerando-se a escassez de trabalhos no Brasil que tratam da micota filamentosa em ambientes marinhos, e ainda a necessidade do conhecimento da diversidade desses microfungos nas praias de Casa Caiada e Bairro Novo, Olinda, PE, este trabalho teve como objetivo o isolamento e identificação de fungos, em amostras de solo e de água, desses ecossistemas. Foram realizadas 32 coletas do solo (em superfície e a 20 cm de profundidade e da água (em superf

  16. A study of global sand seas

    Science.gov (United States)

    McKee, Edwin D.

    1979-01-01

    associated with eolian hydrocarbon reservoirs. The final chapters present a discussion of the morphology and distribution of dunes as determined largely from Landsat images.Chapter K of the publication is devoted to descriptions of major sand seas based largely on thematic maps derived from Landsat (ERTS) mosaics. Although inclusion herein of the actual mosaics proved to be impractical, the maps derived from them do show the distribution and abundance of various dune types and the relations of these types to certain associated features, such as bedrock, water bodies, and juxtaposed dunes. Furthermore, sand roses included with each of these maps enable the user to draw conclusions on the probable relations of wind strength and direction to dune type in a particular area.Regional studies (chapter K) were a team effort. Analysis of the Landsat (ERTS) mosaics and mapping boundaries of individual dune types were by Carol Breed. Synthesis of the rather voluminous literature and preparation of abstracts covering it was by Camilla MacCauley. Actual preparation of maps was by Franci Lennartz and later by Sarah Andrews. The gathering of data on wind, the calculation of wind roses, and the interpretation of their relations to sand bodies were by Steven Fryberger, assisted by Gary Dean.

  17. Oil sands tax expenditures

    International Nuclear Information System (INIS)

    Ketchum, K; Lavigne, R.; Plummer, R.

    2001-01-01

    The oil sands are a strategic Canadian resource for which federal and provincial governments provide financial incentives to develop and exploit. This report describes the Oil Sands Tax Expenditure Model (OSTEM) developed to estimate the size of the federal income tax expenditure attributed to the oil sands industry. Tax expenditures are tax concessions which are used as alternatives to direct government spending for achieving government policy objectives. The OSTEM was developed within the business Income Tax Division of Canada's Department of Finance. Data inputs for the model were obtained from oil sands developers and Natural Resources Canada. OSTEM calculates annual revenues, royalties and federal taxes at project levels using project-level projections of capital investment, operating expenses and production. OSTEM calculates tax expenditures by comparing taxes paid under different tax regimes. The model also estimates the foregone revenue as a percentage of capital investment. Total tax expenditures associated with investment in the oil sands are projected to total $820 million for the period from 1986 to 2030, representing 4.6 per cent of the total investment. 10 refs., 2 tabs., 7 figs

  18. A Improved Seabed Surface Sand Sampling Device

    Science.gov (United States)

    Luo, X.

    2017-12-01

    In marine geology research it is necessary to obtain a suf fcient quantity of seabed surface samples, while also en- suring that the samples are in their original state. Currently,there are a number of seabed surface sampling devices available, but we fnd it is very diffcult to obtain sand samples using these devices, particularly when dealing with fne sand. Machine-controlled seabed surface sampling devices are also available, but generally unable to dive into deeper regions of water. To obtain larger quantities of seabed surface sand samples in their original states, many researchers have tried to improve upon sampling devices,but these efforts have generally produced ambiguous results, in our opinion.To resolve this issue, we have designed an improved andhighly effective seabed surface sand sampling device that incorporates the strengths of a variety of sampling devices. It is capable of diving into deepwater to obtain fne sand samples and is also suited for use in streams, rivers, lakes and seas with varying levels of depth (up to 100 m). This device can be used for geological mapping, underwater prospecting, geological engineering and ecological, environmental studies in both marine and terrestrial waters.

  19. Transport processes in intertidal sand flats

    Science.gov (United States)

    Wu, Christy

    2010-05-01

    Methane rich sulfate depleted seeps are observed along the low water line of the intertidal sand flat Janssand in the Wadden Sea. It is unclear where in the flat the methane is formed, and how it is transported to the edge of the sand flat where the sulfidic water seeps out. Methane and sulfate distributions in pore water were determined along transects from low water line toward the central area of the sand flat. The resulting profiles showed a zone of methane-rich and sulfate-depleted pore water below 2 m sediment depth. Methane production and sulfate reduction are monitored over time for surface sediments collected from the upper flat and seeping area. Both activities were at 22 C twice as high as at 15 C. The rates in sediments from the central area were higher than in sediments from the methane seeps. Methanogenesis occurred in the presence of sulfate, and was not significantly accelerated when sulfate was depleted. The observations show a rapid anaerobic degradation of organic matter in the Janssand. The methane rich pore water is obviously transported with a unidirectional flow from the central area of the intertidal sand flat toward the low water line. This pore water flow is driven by the pressure head caused by elevation of the pore water relative to the sea surface at low tide (Billerbeck et al. 2006a). The high methane concentration at the low water line accumulates due to a continuous outflow of pore water at the seepage site that prevents penetration of electron acceptors such as oxygen and sulfate to reoxidize the reduced products of anaerobic degradation (de Beer et al. 2006). It is, however, not clear why no methane accumulates or sulfate is depleted in the upper 2 m of the flats.

  20. Beach Sand Analysis for Indicators of Microbial Contamination

    Science.gov (United States)

    Traditional beach monitoring has focused on water quality, with little attention paid to health risks associated with beach sand. Recent research has reported that fecal indicator bacteria, as well as human pathogens can be found in beach sand and may constitute a risk to human h...

  1. Pathogen removal using saturated sand colums supplemented with hydrochar

    NARCIS (Netherlands)

    Chung, J.W.

    2015-01-01

    This PhD study has evaluated hydrochars derived from biowastes as adsorbents for pathogen removal in water treatment. Pathogen removal experiments were conducted by carrying out breakthrough analysis using a simple sand filtration set-up. Glass columns packed by 10 cm sand bed supplemented with

  2. Sorption of europium by Haro river sand in aqueous solution

    International Nuclear Information System (INIS)

    Syed Moosa Hasany; Syed Javaid Khurshid

    1997-01-01

    The sorption of Eu(III) on Haro river sand has been investigated. Influences include composition of the sorptive medium, the concentration of sorbent and sorbate, and shaking time. Haro river sand can be exploited for the preconcentration and removal of europium from very dilute solutions, for the decontamination and treatment of radioactive waste water and effluents from nuclear installations. (Author)

  3. Sand Dunes with Frost

    Science.gov (United States)

    2004-01-01

    9 May 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a suite of frost-covered sand dunes in the north polar region of Mars in early spring, 2004. The dunes indicate wind transport of sand from left to right (west to east). These landforms are located near 78.1oN, 220.8oW. This picture is illuminated by sunlight from the lower left and covers an area about 3 km (1.9 mi) across.

  4. Permeability Tests on Silkeborg Sand No. 0000

    DEFF Research Database (Denmark)

    Lund, Willy; Jakobsen, Kim Parsberg

    on the characteristics of the soil matrix, the permeability is determined for different void ratios. All tests are performed on reconstituted specimens of Silkeborg Sand No. 0000. The permeability is determined by use of a falling head apparatus. The apparatus, test procedures and the analysis method are described......The flow through porous media plays an important role in various engineering disciplines, as for example in ground water hydrology and soil mechanics. In the present study the permeability is determined for a fine, saturated sand. As the flow through a porous media strongly depends...

  5. Permeability Tests on Eastern Scheldt Sand

    DEFF Research Database (Denmark)

    Jakobsen, Kim Parsberg

    on the characteristics of the soil matrix, the permeability is determined for different void ratios. All tests are performed on reconstituted specimens of Eastern Scheldt Sand. The permeability is determined by use of a falling head apparatus. Finally the test results are briefly summarised and a relationship between......The flow through porous media plays an important role in various engineering disciplines, as for example in ground water hydrology and soil mechanics. In the present study the permeability is determined for a fine, saturated sand. As the flow through a porous media strongly depends...

  6. Nuclear energy in the oils sands

    International Nuclear Information System (INIS)

    Arsenault, J.E.

    2014-01-01

    The major Canadian oil sands are located in Alberta and Saskatchewan, with most production from the strata along the Athabasca River in Alberta. The economically recoverable oil sands reserves are estimated to be 168 billion barrels which at a current production rate of 1.8 million barrels per day (2012), are projected to last a very long time. Canada has been blessed with vast energy resources which make it potentially energy-independent and able to provide significant exports but there are concerns that their development cannot be managed in a wholly acceptable manner. Comparable concerns have been applied to nuclear energy in the past and in recent times to the oil sands. The technologies associated with these energy sources have always been controversial because they are at the confluence of economics and politics where finding a balance between risk and reward is difficult. So it should be no surprise that when these technologies get linked together in certain proposals their prospect for success is doubly difficult. The possible use of nuclear energy for production of oil from the oil sands dates back to the late 1950s, when an experiment to mine the oil by detonating an underground nuclear device was proposed. It was predicted that the heat and pressure released from such a device would create a large cavern into which oil would flow, and from where it would be pumped to the surface. Almost at the same time, oil sands research using conventional sources of energy had culminated with the development of practical refining processes, essentially those still in use today. These methods require large amounts of heat energy in the form of hot water and steam. In this century nuclear energy was proposed as the source for the heat required by the oil sands production processes. To date neither of these nuclear proposals for oil sands projects have been successful, because the economic and political balance could not be struck. (author)

  7. Nuclear energy in the oils sands

    Energy Technology Data Exchange (ETDEWEB)

    Arsenault, J.E.

    2014-09-15

    The major Canadian oil sands are located in Alberta and Saskatchewan, with most production from the strata along the Athabasca River in Alberta. The economically recoverable oil sands reserves are estimated to be 168 billion barrels which at a current production rate of 1.8 million barrels per day (2012), are projected to last a very long time. Canada has been blessed with vast energy resources which make it potentially energy-independent and able to provide significant exports but there are concerns that their development cannot be managed in a wholly acceptable manner. Comparable concerns have been applied to nuclear energy in the past and in recent times to the oil sands. The technologies associated with these energy sources have always been controversial because they are at the confluence of economics and politics where finding a balance between risk and reward is difficult. So it should be no surprise that when these technologies get linked together in certain proposals their prospect for success is doubly difficult. The possible use of nuclear energy for production of oil from the oil sands dates back to the late 1950s, when an experiment to mine the oil by detonating an underground nuclear device was proposed. It was predicted that the heat and pressure released from such a device would create a large cavern into which oil would flow, and from where it would be pumped to the surface. Almost at the same time, oil sands research using conventional sources of energy had culminated with the development of practical refining processes, essentially those still in use today. These methods require large amounts of heat energy in the form of hot water and steam. In this century nuclear energy was proposed as the source for the heat required by the oil sands production processes. To date neither of these nuclear proposals for oil sands projects have been successful, because the economic and political balance could not be struck. (author)

  8. Sand (CSW4)

    CSIR Research Space (South Africa)

    Estuarine and Coastal Research Unit

    1982-12-01

    Full Text Available This report is one of a series on Cape Estuaries being published under the general title "The Estuaries of the Cape, Part 2". The report provides information on sand estuary: historical background, abiotic and biotic characteristics. It is pointed...

  9. Inland drift sand landscapes

    NARCIS (Netherlands)

    Fanta, J.; Siepel, H.

    2010-01-01

    Man has had a complex relationship with inland drift sands through the ages. For some centuries these landscapes were seen as a threat to society, especially agriculture and housing. At present we conserve these landscapes as important Natura 2000 priority habitats. In this book you may find these

  10. Natural analogues for processes affecting disposal of high-level radioactive waste in the vadose zone

    Science.gov (United States)

    Stuckless, J. S.

    2003-04-01

    Natural analogues can contribute to understanding and predicting the performance of subsystems and processes affecting a mined geologic repository for high-level radioactive waste in several ways. Most importantly, analogues provide tests for various aspects of systems of a repository at dimensional scales and time spans that cannot be attained by experimental study. In addition, they provide a means for the general public to judge the predicted performance of a potential high-level nuclear waste repository in familiar terms such that the average person can assess the anticipated long-term performance and other scientific conclusions. Hydrologists working on the Yucca Mountain Project (currently the U.S. Department of Energy's Office of Repository Development) have modeled the flow of water through the vadose zone at Yucca Mountain, Nevada and particularly the interaction of vadose-zone water with mined openings. Analogues from both natural and anthropogenic examples confirm the prediction that most of the water moving through the vadose zone will move through the host rock and around tunnels. This can be seen both quantitatively where direct comparison between seepage and net infiltration has been made and qualitatively by the excellent degree of preservation of archaeologic artifacts in underground openings. The latter include Paleolithic cave paintings in southwestern Europe, murals and artifacts in Egyptian tombs, painted subterranean Buddhist temples in India and China, and painted underground churches in Cappadocia, Turkey. Natural analogues also suggest that this diversion mechanism is more effective in porous media than in fractured media. Observations from natural analogues are also consistent with the modeled decrease in the percentage of infiltration that becomes seepage with a decrease in amount of infiltration. Finally, analogues, such as tombs that have ben partially filled by mud flows, suggest that the same capillary forces that keep water in the

  11. Eastern Baltic cod : Perspectives from existing data on processes affecting growth and survival of eggs and larvae

    DEFF Research Database (Denmark)

    MacKenzie, Brian; St. John, Michael; Wieland, Kai

    1996-01-01

    exist in our knowledge of processes affecting egg and larval growth and survival, but some promising areas of research are indicated. In particular the seasonality of spawning, deep water oxygen concentrations, predation on eggs, and larval food production require further investigation....... surveys have described food concentrations at appropriate scales for cod larvae, and the species composition of larval diets is unknown. Growth rates for Baltic cod larvae have not been measured and cannot be compared with rates in other areas or to variations in biotic and abiotic factors. Large gaps...

  12. Isotopes based assessment of groundwater renewal and related anthropogenic effects in water scarce areas: Sand dunes study in Qasim area, Saudi Arabia

    International Nuclear Information System (INIS)

    Al-Sagaby, A.; Moallim, A.

    2001-01-01

    The investigation of recharge in the sand dune, Qasim, Saudi Arabia, with the help of chloride concentration and isotope content has revealed inconsistent pattern and less homogeneity. Monotonic chloride concentration and isotope content was the result of seasonal recharge occurrence in the study area. In addition, applying chloride mass-balance method, recharge rate calculation in the sand dune site, Qasim, Saudi Arabia, was made. The results (1.80 and 1.84mmy -1 - dune site) estimated during this project using this method was a long way below the recharge rates (30mmy -1 , 13.4mmy -1 in the dune site and 5mmy -1 in the swale site) obtained with the application of tritium method in the previous years (1994 and 1996). 1.80 and 1.84mmy -1 was for CRP-Saud-9405 project and was calculated 1997 and 1998 respectively. The reason for the lower recharge rate with the application of chloride mass-balance method could be the source of chloride input and high evaporation, which causes accumulation of chloride salts in the area. (author)

  13. The behavior of gaseous iodine in sand

    International Nuclear Information System (INIS)

    Takahashi, Kanji

    1974-01-01

    Radioactive iodine gas was passed through 10 different sands collected at rivers and hills. The relation between the amount of the loaded gas and the amount of adsorbed gas was determined at room temperature, 50 -- 60 0 C, and 90 -- 100 0 C under humidity of 2 sand. This amount was about 1 -- 3 times as much as that of monomolecular membrane adsorption, 0.2 -- 0.3 μg/cm 2 . The decrease of adsorption amount that accompanies the increase of humidity is attributable to the decrease of effective surface area of sand due to the presence of water. The transport of iodine in sand was studied by passing gaseous iodine through a glass tubing packed with sand. The distribution in the flow direction of iodine indicated that the ease of desorption depends upon the situation of adsorption. Easily desorbed case was named Henry type adsorption. Hardly desorbed case was named absorption type. Discussion is made on experimental results. (Fukutomi, T.)

  14. Numerical simulation of flow and compression of green sand

    DEFF Research Database (Denmark)

    Hovad, Emil

    The focus of the industrial PhD project was concentrated on the production of the sand mold (green sand) which gives the cast component its final geometrical shape. In order to ensure a high quality of the cast component, it is important to control the manufacturing process of the mold itself so...... that it is homogeneous and stable. Therefore gaining a basic understanding of how the flow and deposition of green sand should be characterized and modelled was important, so that it could be used for simulation of the manufacturing process of the sand mold. The flowability of the green sand is important when the sand...... flows down through the hopper filling the chamber with sand during the sand shot. The flowability of green sand is mostly governed by the amount of water and bentonite which both decrease it. The flowability and the internal forces thus control how well you can fill a complex mold geom-etry in which...

  15. 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.

  16. On Pluvial Compaction of Sand

    DEFF Research Database (Denmark)

    Jacobsen, Moust

    At the Institute of Civil Engineering in Aalborg model tests on dry sand specimens have been carried out during the last five years. To reduce deviations in test results, the sand laying technique has been carefully studied, and the sand mass spreader constructed. Preliminary results have been...

  17. Evaluation of an Intergrated / Biocoagulant-sand filter Drum for ...

    African Journals Online (AJOL)

    User

    2015-03-18

    Mar 18, 2015 ... to adopt simple sand filtration for water treatment is exigent. ... Moringa oleifera, a vegetable plant found across Africa have been noted ... leachate samples from waste dumps within the city of Bamenda .... Total solids mg/dm3.

  18. 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.

  19. 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.

  20. Nano sand filter with functionalized nanoparticles embedded in anodic aluminum oxide templates

    OpenAIRE

    Phuong, NguyenThi; Andisetiawan, Anugrah; Van Lam, Do; Kim, Jeong Hwan; Choi, Doo-Sun; Whang, Kyung-Hyun; Nham, Jeasun; Lee, Yun Jung; Yoo, Yeong-Eun; Yoon, Jae Sung

    2016-01-01

    Since the ancient Egyptians had used sand as filter media for water purification, its principle has been inherited through generations and it is still being used now in industries. The sand filter consists of sand literally, and the voids within the sand bed are the pores for filtration. Here we present a filtration principle using nanoparticles, so that the voids between the nanoparticles can be considered as effective pores in nanoscale dimension. Anodic aluminum oxide (AAO) membrane has be...

  1. Marine pollution: Let us not forget beach sand

    OpenAIRE

    Galgani, Francois; Ellerbrake, Katrin; Fries, Elke; Goreux, Chantal

    2011-01-01

    Background: Assessing the chemical or bacterial contamination in marine waters and sediments is a very common approach to evaluate marine pollution and associated risks. However, toxicity and organic pollution of beach sands have not yet been considered, except in adjacent waters. In the present study, the toxicity and the chemical contamination of natural beach sands collected 20 m from the shoreline at two sites located on the Mediterranean Sea (Marseille and La Marana, Corsica) were studie...

  2. Early diagenetic processes affecting nutrients in the pore waters of Central Indian Ocean cores

    Digital Repository Service at National Institute of Oceanography (India)

    Nath, B.N.; Mudholkar, A.V.

    and unoxidized organic carbon are observed in the Arabian Sea core, while nitrification with intermediate low nitrate and high organic carbon are found in the mottled zones of the pelagic cores. Mobilization of iron-host oxyhydroxides and peaked profiles...

  3. Habitat selection models for Pacific sand lance (Ammodytes hexapterus) in Prince William Sound, Alaska

    Science.gov (United States)

    Ostrand, William D.; Gotthardt, Tracey A.; Howlin, Shay; Robards, Martin D.

    2005-01-01

    We modeled habitat selection by Pacific sand lance (Ammodytes hexapterus) by examining their distribution in relation to water depth, distance to shore, bottom slope, bottom type, distance from sand bottom, and shoreline type. Through both logistic regression and classification tree models, we compared the characteristics of 29 known sand lance locations to 58 randomly selected sites. The best models indicated a strong selection of shallow water by sand lance, with weaker association between sand lance distribution and beach shorelines, sand bottoms, distance to shore, bottom slope, and distance to the nearest sand bottom. We applied an information-theoretic approach to the interpretation of the logistic regression analysis and determined importance values of 0.99, 0.54, 0.52, 0.44, 0.39, and 0.25 for depth, beach shorelines, sand bottom, distance to shore, gradual bottom slope, and distance to the nearest sand bottom, respectively. The classification tree model indicated that sand lance selected shallow-water habitats and remained near sand bottoms when located in habitats with depths between 40 and 60 m. All sand lance locations were at depths lance and the independent variables are discussed.

  4. Oil sands supply outlook

    International Nuclear Information System (INIS)

    Dunbar, R.

    2004-01-01

    In March 2004, The Canadian Energy Research Institute released a report on the expected future supply from Alberta's oil sands. The report indicates that the future for the already well-established oil sands industry is promising, particularly given the outlook for oil prices. The challenges facing the industry include higher industry supply costs and the need for innovative commercial and technological solutions to address the risks of irregularities and changes in crude oil prices. In 2003, the industry produced 874 thousand barrels per day of synthetic crude oil and unprocessed crude bitumen. This represents 35 per cent of Canada's total oil production. Current production capacity has increased to 1.0 million barrels per day (mbpd) due to new projects. This number may increase to 3.5 mbpd by 2017. Some new projects may be deferred due to the higher raw bitumen and synthetic crude oil supply costs. This presentation provided supply costs for a range of oil sands recovery technologies and production projections under various business scenarios. tabs., figs

  5. Liquefaction resistance of calcareous sands

    International Nuclear Information System (INIS)

    Sandoval Vallejo, Eimar

    2012-01-01

    Calcareous sands are unique in terms of their origin, mineralogy, shape, fragility and intra particle porosity. This article presents results from an experimental program carried out to study the liquefaction resistance of a calcareous sand retrieved from Cabo Rojo at Puerto Rico. The experimental program included mineralogical characterization, index properties, and undrained cyclic triaxial tests on isotropically consolidated reconstituted samples. Due to the large variation in the calcareous sand properties, results are compared with previous researches carried out on other calcareous sands around the world. Results showed a wide range in the liquefaction resistance of the studied calcareous sands. Cabo Rojo sand experienced greater liquefaction resistance than most of the calcareous sands used for comparison. Important differences in the excess pore pressure generation characteristics were also found.

  6. 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.

  7. Booming Sand Dunes

    Science.gov (United States)

    Vriend, Nathalie

    "Booming" sand dunes are able to produce low-frequency sound that resembles a pure note from a music instrument. The sound has a dominant audible frequency (70-105 Hz) and several higher harmonics and may be heard from far distances away. A natural or induced avalanche from a slip face of the booming dune triggers the emission that may last for several minutes. There are various references in travel literature to the phenomenon, but to date no scientific explanation covered all field observations. This thesis introduces a new physical model that describes the phenomenon of booming dunes. The waveguide model explains the selection of the booming frequency and the amplification of the sound in terms of constructive interference in a confined geometry. The frequency of the booming is a direct function of the dimensions and velocities in the waveguide. The higher harmonics are related to the higher modes of propagation in the waveguide. The experimental validation includes quantitative field research at the booming dunes of the Mojave Desert and Death Valley National Park. Microphone and geophone recordings of the acoustic and seismic emission show a variation of booming frequency in space and time. The analysis of the sensor data quantifies wave propagation characteristics such as speed, dispersion, and nonlinear effects and allows the distinction between the source mechanism of the booming and the booming itself. The migration of sand dunes results from a complicated interplay between dune building, wind regime, and precipitation. The morphological and morphodynamical characteristics of two field locations are analyzed with various geophysical techniques. Ground-penetrating radar images the subsurface structure of the dunes and reveal a natural, internal layering that is directly related to the history of dune migration. The seismic velocity increases abruptly with depth and gradually increases with downhill position due to compaction. Sand sampling shows local

  8. Compressive Strength of Compacted Clay-Sand Mixes

    Directory of Open Access Journals (Sweden)

    Faseel Suleman Khan

    2014-01-01

    Full Text Available The use of sand to improve the strength of natural clays provides a viable alternative for civil infrastructure construction involving earthwork. The main objective of this note was to investigate the compressive strength of compacted clay-sand mixes. A natural clay of high plasticity was mixed with 20% and 40% sand (SP and their compaction and strength properties were determined. Results indicated that the investigated materials exhibited a brittle behaviour on the dry side of optimum and a ductile behaviour on the wet side of optimum. For each material, the compressive strength increased with an increase in density following a power law function. Conversely, the compressive strength increased with decreasing water content of the material following a similar function. Finally, the compressive strength decreased with an increase in sand content because of increased material heterogeneity and loss of sand grains from the sides during shearing.

  9. Rapid Return of Nitrogen but not Phosphorus to Ecosystem Nutrition During Decomposition of Quagga Mussel Tissue in Sand, Mud, or Water During Oxic or Anoxic Incubation: Implications for Phytoplankton Bioenergetics.

    Science.gov (United States)

    Cooney, E. M.; Cuhel, R. L.; Aguilar, C.

    2016-02-01

    In 2003 Quagga mussels were found to have invaded Lake Michigan. Their presence has changed the structure of the lake both ecologically (benthification) as well as chemically (oligotrophication). They consume large amounts of phytoplankton, which decreases the particulate nitrogen and phosphorous nutrients available to other consumers including zooplankton. As a result, fisheries productivity has decreased nearly 95%. Recently reaching the end of the first life cycle, in death they release a portion of these nutrients back into the freshwater system during decomposition. This work determined amounts of phosphorus and nitrogen nutrient recycling for several relevant sediment-water interface conditions: oxic vs anoxic in water, mud, or sand over a weeklong period. Concentrations of ammonium, soluble reactive phosphorus, and nitrate were used to analyze nutrient release as decomposition took place. In a short time up to 25% of tissue N was released as ammonia, and under oxic conditions in mud or sand, nitrification converted some of the ammonia to nitrate. Unexpectedly, mussels decaying in anoxic conditions released ammonium much more slowly. A slower rate of release in ammonium for the intact body with the shell (burial) was observed when compared to ground mussel tissue (detritivory). Nitrate was removed in anoxic incubations, indicating anaerobic denitrification. Phosphate release was initially higher under anoxic conditions than those decaying aerobically. There was no significant difference in the amount or rate of release of SRP between ground mussel and whole bodied with the shell. The anoxic treatment showed similar patterns of release for both ground mussel and intact body with shell. Most important, phosphate was subsequently removed in all treatments and diffusible nutrient was minimal (<100nM). The results link to nutrient assimilation patterns of deep phytoplankton communities, which can replace nitrate with ammonium as an N source.

  10. Sand waves on an epicontinental shelf: Northern Bering Sea

    Science.gov (United States)

    Field, M.E.; Nelson, C.H.; Cacchione, D.A.; Drake, D.E.

    1981-01-01

    Sand waves and current ripples occupy the crests and flanks of a series of large linear sand ridges (20 km ?? 5 km ?? 10 m high) lying in an open-marine setting in the northern Bering Sea. The sand wave area, which lies west of Seward Peninsula and southeast of Bering Strait, is exposed to the strong continuous flow of coastal water northward toward Bering Strait. A hierarchy of three sizes of superimposed bedforms, all facing northward, was observed in successive cruises in 1976 and 1977. Large sand waves (height 2 m; spacing 200 m) have smaller sand waves (height 1 m; spacing 20 m) lying at a small oblique angle on their stoss slopes. The smaller sand waves in turn have linguoid ripples on their stoss slopes. Repeated studies of the sand wave fields were made both years with high-resolution seismic-reflection profiles, side-scan sonographs, underwater photographs, current-meter stations, vibracores, and suspended-sediment samplers. Comparison of seismic and side-scan data collected along profile lines run both years showed changes in sand wave shape that indicate significant bedload transport within the year. Gouge marks made in sediment by keels of floating ice also showed significantly different patterns each year, further documenting modification to the bottom by sediment transport. During calm sea conditions in 1977, underwater video and camera observations showed formation and active migration of linguoid and straight-crested current ripples. Current speeds 1 m above the bottom were between 20 and 30 cm/s. Maximum current velocities and sand wave migration apparently occur when strong southwesterly winds enhance the steady northerly flow of coastal water. Many cross-stratified sand bodies in the geologic record are interpreted as having formed in a tidal- or storm-dominated setting. This study provides an example of formation and migration of large bedforms by the interaction of storms with strong uniform coastal currents in an open-marine setting. ?? 1981.

  11. Sediment Source Fingerprinting of the Lake Urmia Sand Dunes.

    Science.gov (United States)

    Ahmady-Birgani, Hesam; Agahi, Edris; Ahmadi, Seyed Javad; Erfanian, Mahdi

    2018-01-09

    Aeolian sand dunes are continuously being discovered in inner dry lands and coastal areas, most of which have been formed over the Last Glacial Maximum. Presently, due to some natural and anthropogenic implications on earth, newly-born sand dunes are quickly emerging. Lake Urmia, the world's second largest permanent hypersaline lake, has started shrinking, vast lands comprising sand dunes over the western shore of the lake have appeared and one question has been playing on the minds of nearby dwellers: where are these sand dunes coming from, What there was not 15 years ago!! In the present study, the determination of the source of the Lake Urmia sand dunes in terms of the quantifying relative contribution of each upstream geomorphological/lithological unit has been performed using geochemical fingerprinting techniques. The findings demonstrate that the alluvial and the fluvial sediments of the western upstream catchment have been transported by water erosion and they accumulated in the lower reaches of the Kahriz River. Wind erosion, as a secondary agent, have carried the aeolian sand-sized sediments to the sand dune area. Hence, the Lake Urmia sand dunes have been originating from simultaneous and joint actions of alluvial, fluvial and aeolian processes.

  12. Effectiveness of SCADA Systems in Control of Green Sands Properties

    Directory of Open Access Journals (Sweden)

    Ignaszak Z.

    2016-03-01

    Full Text Available The paper undertakes an important topic of evaluation of effectiveness of SCADA (Supervisory Control and Data Acquisition systems, used for monitoring and control of selected processing parameters of classic green sands used in foundry. Main focus was put on process studies of properties of so-called 1st generation molding sands in the respect of their preparation process. Possible methods of control of this processing are presented, with consideration of application of fresh raw materials, return sand (regenerate and water. The studies conducted in one of European foundries were aimed at pointing out how much application of new, automated plant of sand processing incorporating the SCADA systems allows stabilizing results of measurement of selected sand parameters after its mixing. The studies concerned two comparative periods of time, before an implementation of the automated devices for green sands processing (ASMS - Automatic Sand Measurement System and MCM – Main Control Module and after the implementation. Results of measurement of selected sand properties after implementation of the ASMS were also evaluated and compared with testing studies conducted periodically in laboratory.

  13. Laboratory studies of dune sand for the use of construction industry in Sri Lanka

    Science.gov (United States)

    de Silva Jayawardena, Upali; Wijesuriya, Roshan; Abayaweera, Gayan; Viduranga, Tharaka

    2015-04-01

    With the increase of the annual sand demand for the construction industry the excessive excavation of river sand is becoming a serious environmental problem in Sri Lanka. Therefore, it is necessary to explore the possibility for an alternative to stop or at least to minimize river sand mining activities. Dune sand is one of the available alternative materials to be considered instead of river sand in the country. Large quantities of sand dunes occur mainly along the NW and SE coastal belt which belong to very low rainfall Dry Zone coasts. The height of dune deposits, vary from 1m to about 30 meters above sea level. The objective of this paper is to indicate some studies and facts on the dune sand deposits of Sri Lanka. Laboratory studies were carried out for visual observations and physical properties at the initial stage and then a number of tests were carried out according to ASTM standards to obtain the compressive strength of concrete cylinders and mortar cubes mixing dune sand and river sand in different percentages keeping a constant water cement ratio. Next the water cement ratio was changed for constant dune sand and river sand proportion. Microscopic analysis shows that the dune sand consist of 95 % of quartz and 5 % of garnet, feldspar, illmenite and other heavy minerals with clay, fine dust, fine shell fragments and organic matters. Grains are sub-rounded to angular and tabular shapes. The grain sizes vary from fine to medium size of sand with silt. The degree of sorting and particle size observed with dune sands are more suited with the requirement of fine aggregates in the construction industry. The test result indicates that dune sand could be effectively used in construction work without sieving and it is ideal for wall plastering due to its'-uniformity. It could also be effectively used in concrete and in mortars mixing with river sand. The best mixing ratio is 75% dune sand and 25% river sand as the fine aggregate of concrete. For mortar the mixing

  14. 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

  15. Compressive behavior of fine sand.

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Bradley E. (Air Force Research Laboratory, Eglin, FL); Kabir, Md. E. (Purdue University, West Lafayette, IN); Song, Bo; Chen, Wayne (Purdue University, West Lafayette, IN)

    2010-04-01

    The compressive mechanical response of fine sand is experimentally investigated. The strain rate, initial density, stress state, and moisture level are systematically varied. A Kolsky bar was modified to obtain uniaxial and triaxial compressive response at high strain rates. A controlled loading pulse allows the specimen to acquire stress equilibrium and constant strain-rates. The results show that the compressive response of the fine sand is not sensitive to strain rate under the loading conditions in this study, but significantly dependent on the moisture content, initial density and lateral confinement. Partially saturated sand is more compliant than dry sand. Similar trends were reported in the quasi-static regime for experiments conducted at comparable specimen conditions. The sand becomes stiffer as initial density and/or confinement pressure increases. The sand particle size become smaller after hydrostatic pressure and further smaller after dynamic axial loading.

  16. Canada's oil sands : opportunities and challenges to 2015 : an update

    International Nuclear Information System (INIS)

    2006-06-01

    This report updated an energy market assessment compiled and published by the National Energy Board (NEB) in 2004. Major changes resulting from recent developments in the oil sands industry were presented. The report was compiled from a series of informal meetings and discussions with a cross-section of oil sands stakeholders. Influences on recent oil sands development and production growth included market development and pipelines; rising capital and labour costs; operating costs; environmental impact management; high crude oil prices; rising global energy demand; technology innovations; and a more stable investment climate. A comparison of key assumptions between the current analysis and the 2004 report was presented, along with estimates of operating and supply costs for various types of oil sands recovery methods. Potential markets for oil sands production were reviewed. Environmental and socio-economic impacts on the industry included the larger than anticipated water withdrawals from the Athabasca River for mining operations; and uncertainties over land reclamation methods. The industry has also been impacted by a limited supply of skilled workers in Alberta. It was observed that the potential for building cogeneration capacity has decreased since the 2004 report. It was concluded that the oil sands industry will continue to grow rapidly, but the rate of development will depend on the balance that is reached between the opposing forces that affect the oil sands. Natural gas costs, high oil prices, air emissions management issues and water usage will continue to be of concern. 6 tabs., 7 figs

  17. Flowability in crushed sand mortar

    Directory of Open Access Journals (Sweden)

    Cabrera, O. A.

    2010-12-01

    Full Text Available The present experimental study explored the relationship between mortar flowability and the voids content in crushed sand to determine the effect of grain shape and surface texture as well as dust content on the behaviour of fresh mortar. The findings revealed a close correlation between voids content and the volume of paste needed for mortar to begin to flow as a continuous material, mortar flowability and the water content needed to attain a given flowability. The comparison of the empirical findings to the results obtained with the Larrard (1, 2 model provided further information on the effect of sand grain morphology on fresh mortars.

    En el presente trabajo se plantea un estudio experimental de la fluidez de morteros basado en el contenido de vacíos de arenas machacadas, para comprender la influencia de la forma y textura superficial de los granos de arena y del contenido de polvo de las mismas sobre el estado fresco de morteros. Los resultados muestran la estrecha relación entre el contenido de vacíos entre granos y los volúmenes de pasta necesarios para iniciar el escurrimiento como un material continuo, la fluidez de los morteros, el contenido de agua para alcanzar una determinada fluidez, etc. El comportamiento evaluado se compara con resultados obtenidos aplicando el modelo de F. de Larrard (1, 2, permitiendo de este modo obtener mayor información de la influencia de la morfología de los granos de la arena sobre el estado fresco de los morteros.

  18. Tratamento de esgoto e produção de água de reúso com o emprego de filtros de areia Wastewater treatment and reuse water production using sand filters

    Directory of Open Access Journals (Sweden)

    Adriano Luiz Tonetti

    2012-09-01

    Full Text Available Nesta pesquisa estudou-se um sistema composto pela combinação de filtro anaeróbio com filtro de areia para o tratamento de esgoto. Para isso, foram avaliados três filtros anaeróbios operados com tempo de detenção hidráulica de nove horas, que tinham o efluente disposto sobre quatro filtros de areia em distintas taxas de aplicações. No primeiro filtro de areia aplicaram-se 50 L.m-2 uma vez por dia. No segundo, terceiro e quarto filtros, essa mesma carga foi disposta em dois, três e quatro horários, espaçadas entre às 9:00 e às 16:00 horas. O sistema apresentou um efluente final com qualidade que atendia os padrões para reúso e demanda bioquímica de oxigênio abaixo do limite para o lançamento em corpos hídricos (Decreto de Paulista nº 8.468/1976, indicando a viabilidade de disposição de taxas superiores às sugeridas pela NBR 13969/1997, a qual orienta os aspectos construtivos para esta forma de tratamento.In this research it was studied a system composed by the anaerobic filter combined with a sand filter for the wastewater treatment. For this, three anaerobic filters were operated with hydraulic detention time of nine hours which had the effluent disposed over four sand filters in different frequencies of application. On the first sand filter, 50 L.m-2 were applied once a day. On the second, the third and the fourth filters, the same load was disposed in twice, three and four times a day, distributed between 9 a.m. and 4 p.m. The system presented a final effluent suitable for the COD and BOD legislation maximum limit to be discharged into water body (Decreto Paulista nº 8,468/1976, showing the viability of dispose a higher quantity of effluent then the one suggested by NBR 13969/1997, which guides the constructive aspects for this kind of treatment.

  19. Measurement of fine particulate matter water-soluble inorganic species and precursor gases in the Alberta Oil Sands Region using an improved semicontinuous monitor.

    Science.gov (United States)

    Hsu, Yu-Mei; Clair, Thomas A

    2015-04-01

    The ambient ion monitor-ion chromatography (AIM-IC) system, which provides hourly measurements of the main chemical components of PM2.5 (particulate matter with an aerodynamic diametergases, was evaluated and deployed from May to July 2011 and April to December 2013 in the Athabasca Oil Sands Region (AOSR) of northeastern Alberta, Canada. The collection efficiencies for the gas-phase SO2 and HNO3 using the cellulose membrane were 96% and 100%, respectively, and the collection efficiency of NH3 using the nylon membrane was 100%. The AIM-IC was compared with a collocated annular denuder sampling system (ADSS) and a Federal Reference Method (FRM) Partisol PM2.5 sampler. The correlation coefficients of SO4(2-) concentrations between the AIM-IC and ADSS and between the AIM-IC and the Partisol PM2.5 sampler were 0.98 and 0.95, respectively. The comparisons also showed no statistically significant difference between the measurement sets, suggesting that the AIM-IC measurements of the PM2.5 chemical composition are comparable to the ADSS and Partisol PM2.5 methods. NH3 concentration in the summer (mean±standard deviation, 1.9±0.7 µg m(-3)) was higher than in the winter (1.3±0.9 µg m(-3)). HNO3 and NO3- concentrations were generally low in the AOSR, and especially in the winter months. NH4+ (0.94±0.96 µg m(-3)) and SO4(2-) (0.58±0.93 µg m(-3)) were the major ionic species of PM2.5. Direct SO2 emissions from oil sands processing operations influenced ambient particulate NH4+ and SO4(2-) values, with hourly concentrations of NH4+ and SO4(2-) measured downwind (~30 km away from the stack) at 10 and 28 µg m(-3). During the regional forest fire event in 2011, high concentrations of NO3-, NH4+, HNO3, NH3, and PM2.5 were observed and the corresponding maximum hourly concentrations were 31, 15, 9.6, 89, and >450 (the upper limit of PM2.5 measurement) µg m(-3), suggesting the formation of NH4NO3. The AOSR in Canada is one of the most scrutinized industrial regions in the

  20. High Temperature Thermal Properties of Bentonite Foundry Sand

    Directory of Open Access Journals (Sweden)

    Krajewski P.K.

    2015-06-01

    Full Text Available The paper presents results of measuring thermal conductivity and heat capacity of bentonite foundry sand in temperature range ambient - 900­­°C. During the experiments a technical purity Cu plate was cast into the green-sand moulds. Basing on measurements of the mould temperature field during the solidification of the casting, the temperature relationships of the measured properties were evaluated. It was confirmed that water vaporization strongly influences thermal conductivity of the moulding sand in the first period of the mould heating by the poured casting.

  1. Perfil ambiental qualitativo da extração de areia em cursos d'água Qualitative environmental profile of sand extraction from water courses

    Directory of Open Access Journals (Sweden)

    Leandro Camillo de Lelles

    2005-06-01

    Full Text Available As atividades de extração de areia são de grande importância para o desenvolvimento social, mas igualmente responsáveis por impactos ambientais negativos, alguns inclusive irreversíveis. Nesse sentido, este trabalho teve como objetivo central avaliar qualitativamente os impactos ambientais decorrentes desse tipo de empreendimento. A identificação e caracterização qualitativa dos impactos ambientais foram feitas, utilizando-se o método do ";check-list";. Os resultados por meio do método do ";check-list"; possibilitaram identificar 49 impactos, sendo 36 negativos (73,47% e 13 positivos (26,53%. A principal conclusão é a de que este estudo pode ser utilizado como referencial teórico para subsidiar o processo de licenciamento ambiental desse tipo de empreendimento.Sand extraction activities are of great importance for social development, however they are also responsible for negative and sometimes irreversible environmental impacts. In this context, this study aimed mainly at the qualitative evaluation of environmental impacts entailed by this kind of enterprise. The check-list method was used for the identification and qualitative characterization of environmental impacts. A number of 49 impacts were identified by the obtained results, 36 of which were negative (73,47%, and 13 positive (26,53%. The most important conclusion was that this study can serve as a theoretical reference to support the process of environmental licensing of projects in these types of enterprises.

  2. 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.

  3. Sand wave fields beneath the Loop Current, Gulf of Mexico: Reworking of fan sands

    Science.gov (United States)

    Kenyon, Neil H.; Akhmetzhanov, A.M.; Twichell, D.C.

    2002-01-01

    Extensive fields of large barchan-like sand waves and longitudinal sand ribbons have been mapped by deep-towed SeaMARC IA sidescan sonar on part of the middle and lower Mississippi Fan that lies in about 3200 m of water. The area is beneath the strongly flowing Loop Current. The bedforms have not been adequately sampled but probably consist of winnowed siliciclastic-foraminiferal sands. The size (about 200 m from wingtip to wingtip) and shape of the large barchans is consistent with a previously observed peak current speed of 30 cm/s, measured 25 m above the seabed. The types of small-scale bedforms and the scoured surfaces of chemical crusts, seen on nearby bottom photographs, indicate that near-bed currents in excess of 30 cm/s may sometimes occur. At the time of the survey the sand transport direction was to the northwest, in the opposite direction to the Loop Current but consistent with there being a deep boundary current along the foot of the Florida Escarpment. Some reworking of the underlying sandy turbidites and debris flow deposits is apparent on the sidescan sonar records. Reworking by deep-sea currents, resulting in erosion and in deposits characterised by coarsening upwards structures and cross-bedding, is a process that has been proposed for sand found in cores in shallower parts of the Gulf of Mexico. This process is more widespread than hitherto supposed. 

  4. Model test study of evaporation mechanism of sand under constant atmospheric condition

    OpenAIRE

    CUI, Yu Jun; DING, Wenqi; SONG, Weikang

    2014-01-01

    The evaporation mechanism of Fontainebleau sand using a large-scale model chamber is studied. First, the evaporation test on a layer of water above sand surface is performed under various atmospheric conditions, validating the performance of the chamber and the calculation method of actual evaporation rate by comparing the calculated and measured cumulative evaporations. Second,the evaporation test on sand without water layer is conducted under constant atmospheric condition. Both the evoluti...

  5. Rheological Characterization of Green Sand Flow

    DEFF Research Database (Denmark)

    Jabbaribehnam, Mirmasoud; Spangenberg, Jon; Hovad, Emil

    2016-01-01

    The main aim of this paper is to characterize experimentally the flow behaviour of the green sand that is used for casting of sand moulds. After the sand casting process is performed, the sand moulds are used for metal castings. The rheological properties of the green sand is important to quantif...

  6. The provenance of Taklamakan desert sand

    Science.gov (United States)

    Rittner, Martin; Vermeesch, Pieter; Carter, Andrew; Bird, Anna; Stevens, Thomas; Garzanti, Eduardo; Andò, Sergio; Vezzoli, Giovanni; Dutt, Ripul; Xu, Zhiwei; Lu, Huayu

    2016-03-01

    Sand migration in the vast Taklamakan desert within the Tarim Basin (Xinjiang Uyghur Autonomous region, PR China) is governed by two competing transport agents: wind and water, which work in diametrically opposed directions. Net aeolian transport is from northeast to south, while fluvial transport occurs from the south to the north and then west to east at the northern rim, due to a gradual northward slope of the underlying topography. We here present the first comprehensive provenance study of Taklamakan desert sand with the aim to characterise the interplay of these two transport mechanisms and their roles in the formation of the sand sea, and to consider the potential of the Tarim Basin as a contributing source to the Chinese Loess Plateau (CLP). Our dataset comprises 39 aeolian and fluvial samples, which were characterised by detrital-zircon U-Pb geochronology, heavy-mineral, and bulk-petrography analyses. Although the inter-sample differences of all three datasets are subtle, a multivariate statistical analysis using multidimensional scaling (MDS) clearly shows that Tarim desert sand is most similar in composition to rivers draining the Kunlun Shan (south) and the Pamirs (west), and is distinctly different from sediment sources in the Tian Shan (north). A small set of samples from the Junggar Basin (north of the Tian Shan) yields different detrital compositions and age spectra than anywhere in the Tarim Basin, indicating that aeolian sediment exchange between the two basins is minimal. Although river transport dominates delivery of sand into the Tarim Basin, wind remobilises and reworks the sediment in the central sand sea. Characteristic signatures of main rivers can be traced from entrance into the basin to the terminus of the Tarim River, and those crossing the desert from the south to north can seasonally bypass sediment through the sand sea. Smaller ephemeral rivers from the Kunlun Shan end in the desert and discharge their sediment there. Both river run

  7. The Relationship Between Microscopic Grain Surface Structure and the Dynamic Capillary-Driven Advance of Water Films over Individual Dry Natural Sand Grains

    Science.gov (United States)

    Kibbey, T. C. G.; Adegbule, A.; Yan, S.

    2017-12-01

    The movement of nonvolatile solutes in unsaturated porous media at low water contents depends on transport in surface-associated water films. The focus of the work described here was on studying solute movement in water films advancing by capillary forces over initially-dry grain surfaces, to understand how microscopic surface roughness features influence the initial velocity of water film advance. For this work, water containing a non-adsorbing conservative tracer was used to track the movement of advancing water films. A stainless steel capillary tube connected to an external reservoir a fixed distance below the grain surface was used to transmit solution to the grain surface under negative pressure (positive capillary pressure), consistent with conditions that might be expected in the unsaturated zone. The small internal diameter of the capillary prevents solution from draining out of the capillary back into the reservoir. When the capillary is contacted with a grain surface, capillary forces that result from contact between the fluid and the rough grain surface cause water films to wick across the grain surface. Multiple experiments were conducted on the same grain, rotating the grain and varying the capillary contact point around the circumference of the grain. Imaging was conducted at fixed intervals using an automated Extended Depth of Field (EDF) imaging system, and images were analyzed to determine initial velocity. Grain surfaces were then characterized through scanning electron microscope (SEM) imaging, using a hybrid stereoscopic reconstruction method designed to extract maximum detail in creating elevation maps of geologic surfaces from tilted pairs of SEM images. The resulting elevation maps were used to relate surface roughness profiles around the grain with initial velocities. Results suggest that velocity varies significant with contact point around an individual grain, and correlates quantitatively with the local grain surface structure

  8. The Geodiversity in Drift Sand Landscapes of The Netherlands

    Science.gov (United States)

    van den Ancker, Hanneke; Jungerius, Pieter Dirk; Riksen, Michel

    2015-04-01

    The authors carried out detailed field studies of more than twelve drift sand landscapes in The Netherlands. The objective of these studies was to restore Natura-2000 values by restoring the wind activity. Active drift sands occur almost exclusively in The Netherlands, Natura 2000 habitat 2330 'Inland dunes with open Corynephorus and Agrostis grasslands', for which reason our country is largely responsible for this European landscape. Active drift sands had almost disappeared for two reasons: first, the stabilization of the drift sands by air pollution, mainly nitrogen, which stimulates the growth of algae and grasses that initiate soil formation, and second, by the growth of forests surrounding the sands, which decreases the wind force. The restoration studies revealed differences in the geodiversity between and within the drift sand areas. Whereas the drift sands on geological and soil maps show as almost homogenous areas, they have in fact highly variable geo-conditions of which examples will be given. These geodiversity aspects concern differences in geomorphological structure, origin, sediments and age of the drift sands. Differences in wind and water erosion, trampling and soil formation add to the geodiversity within the drift sand areas. Especially in the primary stages of succession the differences in geodiversity are relevant for the Natura-2000 values. We discerned three main types of active sands. Firstly, the impressive drift sands with large parabolic dune structures, often consisting of series of interlocking parabolic dunes. They developed from the northeast towards the southwest, against the direction of the dominant wind, and must have taken centuries to develop. Small parts of these systems are still active, other parts show different degrees of soil formation. Their origin is still unclear but probably dates from medieval times (Heidinga, 1985, Jungerius & Riksen, 2008). Second are the drift sand areas with irregular hills from 0.5 to about 2

  9. 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.

  10. The influence of tagasaste (chamaecytisus proliferus link) trees on the water balance of an alley cropping system on deep sand in south-western Australia)

    International Nuclear Information System (INIS)

    Lefroy, E.C.; Pate, J.S.; Stirzaker, R.J.

    2001-01-01

    Components of the water balance of an alley cropping system were measured to assess the extent to which tree rows 30 m apart with access to a fresh, perched watertable at 5 m depth were able to capture deep drainage from an inter-cropped cereal-legume rotation. Neutron probe data showed that the 4-year-old trees, cut back to 0.6-m high at the beginning of the experiment, depleted soil water to 2, 4, and 8 m laterally from the tree rows in their first, second, and third years of coppice regrowth, respectively. Combining data from soil water depletion in summer and comparisons of deuterium/hydrogen ratios of groundwater, xylem sap of trees, and herbaceous plants, it was shown that tagasaste trees drew on soil water for 80% of their transpiration in the first winter and 40% in the second, while switching to near total dependence on groundwater each summer and early autumn. Tree water use on a whole plot basis was 170 mm in 1997 (68% from groundwater) v. 167 mm in 1998 (73% from groundwater). Recharge to the perched watertable was estimated to be 193 mm under sole crop in 1998 (52% of rainfall), reducing to 32 mm when uptake of groundwater by trees was included. The degree of complementarity between tagasaste trees and crops in alley cropping used for water management is quantified for 1998 by calculating the ratio of the distance over which trees reduced drainage to zero to the distance over which they reduced crop yield to zero. It is concluded that segregated monocultures of trees and crops would be a more appropriate strategy than a closely integrated system such as alley cropping in this case. Copyright (2001) CSIRO Australia

  11. Riddle of the sands

    Energy Technology Data Exchange (ETDEWEB)

    Rolheiser, P

    1998-09-01

    A geological model of the Alberta landscape during the period stretching from about 110 million to 100 million years ago during the Cretaceous period when dinosaurs roamed the earth, was sketched. Today, the region contains the Cold Lake oil sands deposit. Imperial Oil began large-scale production at Cold Lake in 1985. The formations within the area are the source of almost half of Imperial Oil`s daily crude oil production and account for one in every 20 barrels of oil produced daily in Canada. The bitumen is produced using cyclic steam stimulation where steam is injected at high pressure into the underground reservoir, fracturing the sandstone and heating the bitumen it holds to thin it so that it can then flow through well bores to the surface. Conventional geological theory suggested that the Cold Lake reservoir was the remains of a prehistoric river delta. In 1994, Imperial Oil established a Cold Lake sequence stratigraphy project to verify this theory. This highly complex project involves volumes of geophysical well-log data from the 2,500 wells at Cold Lake, core samples cut from more than 600 of these wells and microscopic fossilized remains of 100-million-year-old flora extracted from the core samples, and seismic information. The interpreted data helps to create a three-dimensional model of the reservoir`s structure and help define its boundaries. Results have shown that the Cold Lake deposit was created from at least 13 intersecting river beds. Each of the rivers flowed for a few hundred thousand years and deposited sands of varying quality in different layers and patterns. The oil came about 40 million years later after the plant and animal materials containing hydrogen and carbon were broken down by heat and pressure to form oil. 1 fig.

  12. 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.

  13. Sphere impact and penetration into wet sand

    KAUST Repository

    Marston, J. O.

    2012-08-07

    We present experimental results for the penetration of a solid sphere when released onto wet sand. We show, by measuring the final penetration depth, that the cohesion induced by the water can result in either a deeper or shallower penetration for a given release height compared to dry granular material. Thus the presence of water can either lubricate or stiffen the granular material. By assuming the shear rate is proportional to the impact velocity and using the depth-averaged stopping force in calculating the shear stress, we derive effective viscosities for the wet granular materials.

  14. Sphere impact and penetration into wet sand

    KAUST Repository

    Marston, J. O.; Vakarelski, Ivan Uriev; Thoroddsen, Sigurdur T

    2012-01-01

    We present experimental results for the penetration of a solid sphere when released onto wet sand. We show, by measuring the final penetration depth, that the cohesion induced by the water can result in either a deeper or shallower penetration for a given release height compared to dry granular material. Thus the presence of water can either lubricate or stiffen the granular material. By assuming the shear rate is proportional to the impact velocity and using the depth-averaged stopping force in calculating the shear stress, we derive effective viscosities for the wet granular materials.

  15. On whether mirror neurons play a significant role in processing affective prosody.

    Science.gov (United States)

    Ramachandra, Vijayachandra

    2009-02-01

    Several behavioral and neuroimaging studies have indicated that both right and left cortical structures and a few subcortical ones are involved in processing affective prosody. Recent investigations have shown that the mirror neuron system plays a crucial role in several higher-level functions such as empathy, theory of mind, language, etc., but no studies so far link the mirror neuron system with affective prosody. In this paper is a speculation that the mirror neuron system, which serves as a common neural substrate for different higher-level functions, may play a significant role in processing affective prosody via its connections with the limbic lobe. Actual research must apply electrophysiological and neuroimaging techniques to assess whether the mirror neuron systems underly affective prosody in humans.

  16. Research for the development of the crushed sand (II)

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chul Whan; Kang, Sun Duck; Min, Jeong Sik; Synn, Joong Ho; Park, Chan [Korea Institute of Geology Mining and Materials, Taejon (Korea)

    1998-12-01

    The sand obtained from river is not sufficient in amount for the demand of construction industry. The production of sand from sea and mountain is rapidly increasing for the substitution of the river sand. The industry of the crushed sand has recently been bricked for the above. Crushing, classification and dewatering are the main processes in the crushed sand production. This report concentrates the improvement of classification technology and the quality of ready mixed concrete. Air separator with testing size for the classification in the process of dry system was developed by the Yeung Nam university. This plant has the excellent efficiency for the collection of fine powder, but needs the improvement for separating function. The collection efficiency of the testing size air separator is reached to 99% in the condition of high revolution and low feeding speed. The classification efficiency is checked about 50% maximum in the condition of 200 rpm and dry sample. Energy saving test was carried out in the production process of the dry system with the rock samples of 14-17% of water content. The classification efficiency for dewatering sample passed the heating process was analysed 91.5%. But that for high water content sample skipped the heating process was analysed more or less 77%. Even though the heating process causes the classification efficiency being high, the energy consumption can also cause the price of the crushed sand high. Water content of sample as the effective element for the optimization of classification efficiency and energy saving should be studied next year. The quality of crushed sand in the mixing design. The test was carried out with the various content in mixing, the strength of ready mixed concrete has the maximum for the mould with 50-60% content of crushed sand. This strength is higher by 5-30% than 30% content and by 20-32% than 0% content, which means that the industry has the possibility of progress. (author). 10 refs., 31 tabs., 49

  17. The Alberta oil sands story

    Energy Technology Data Exchange (ETDEWEB)

    1974-01-01

    This report serves as a detailed introduction to the Alberta oil sands and their development. It includes a description of the oil sands deposits, an outline of crude bitumen recovery and upgrading processes, the role of Alberta Energy Company in oil sands development, environmental aspects, manpower requirements for oil sands development, research needs, and further oil sands projects. Presently proven recoverable reserves in the oil sands amount to 26.5 billion bbl of synthetic crude. Production from the Syncrude plant (125,000 bbl/d capacity) is expected to begin in 1977, followed by a Shell Canada operation around 1980. The provincial government will participate in the oil sand industry through its joint venture participation in Syncrude and its 50% share in Alberta Energy Company; the latter company participates in related aspects of the Syncrude project, such as pipelines. The result of Alberta's participation in the industry will mean that, directly or indirectly, the province will realize 60% of the total profits. The job creation potential of oil sands projects is estimated to be extensive, with a direct and indirect work force supported by oil sands activities possibly reaching 180,000 persons by the year 2000. Research needs have been identified, particularly in the area of in-situ thermal recovery technology, and the creation of the Alberta Oil Sands Technology and Research Authority has been authorized in order to meet these needs. Although current reserves are sufficient to support 20-30 synthetic crude plants, a number of factors will limit expansion of the industry. 8 figs., 5 tabs.

  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. 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.

  20. Estimation of bare soil evaporation for different depths of water table in the wind-blown sand area of the Ordos Basin, China

    Science.gov (United States)

    Chen, Li; Wang, Wenke; Zhang, Zaiyong; Wang, Zhoufeng; Wang, Qiangmin; Zhao, Ming; Gong, Chengcheng

    2018-04-01

    Soil surface evaporation is a significant component of the hydrological cycle, occurring at the interface between the atmosphere and vadose zone, but it is affected by factors such as groundwater level, soil properties, solar radiation and others. In order to understand the soil evaporation characteristics in arid regions, a field experiment was conducted in the Ordos Basin, central China, and high accuracy sensors of soil moisture, moisture potential and temperature were installed in three field soil profiles with water-table depths (WTDs) of about 0.4, 1.4 and 2.2 m. Soil-surface-evaporation values were estimated by observed data combined with Darcy's law. Results showed that: (1) soil-surface-evaporation rate is linked to moisture content and it is also affected by air temperature. When there is sufficient moisture in the soil profile, soil evaporation increases with rising air temperature. For a WTD larger than the height of capillary rise, the soil evaporation is related to soil moisture content, and when air temperature is above 25 °C, the soil moisture content reduces quickly and the evaporation rate lowers; (2) phreatic water contributes to soil surface evaporation under conditions in which the WTD is within the capillary fringe. This indicates that phreatic water would not participate in soil evaporation for a WTD larger than the height of capillary rise. This finding developed further the understanding of phreatic evaporation, and this study provides valuable information on recognized soil evaporation processes in the arid environment.

  1. A biocoagulant slow sand filtration for disinfection of Toxoplasma ...

    African Journals Online (AJOL)

    An integrated low-tech biocoagulant-sand filter drum for disinfection of oocysts of Toxoplasma gondii targeted for developing countries was evaluated. Dirty and turbid water (130.3 NTU) from Mezam River and leachates from dump sites and stagnant water in Bamenda, Cameroon, was analyzed microscopically after ...

  2. Occurrence of Radium-224, Radium-226 and Radium-228 in Water from the Vincentown and Wenonah-Mount Laurel Aquifers, the Englishtown Aquifer System, and the Hornerstown and Red Bank Sands, Southwestern and South-Central New Jersey

    Science.gov (United States)

    dePaul, Vincent T.; Szabo, Zoltan

    2007-01-01

    This investigation is the first regionally focused study of the presence of natural radioactivity in water from the Vincentown and Wenonah-Mount Laurel aquifers, Englishtown aquifer system, and the Hornerstown and Red Bank Sands. Geologic materials composing the Vincentown and Wenonah-Mount Laurel aquifers and the Hornerstown and Red Bank Sands previously have been reported to contain radioactive (uranium-enriched) phosphatic strata, which is common in deposits from some moderate-depth coastal marine environments. The decay of uranium and thorium gives rise to natural radioactivity and numerous radioactive progeny, including isotopes of radium. Naturally occurring radioactive isotopes, especially those of radium, are of concern because radium is a known human carcinogen and ingestion (especially in water used for drinking) can present appreciable health risks. A regional network in southwestern and south-central New Jersey of 39 wells completed in the Vincentown and Wenonah-Mount Laurel aquifers, the Englishtown aquifer system, and the Hornerstown and Red Bank Sands was sampled for determination of gross alpha-particle activity; concentrations of radium radionuclides, major ions, and selected trace elements; and physical properties. Concentrations of radium-224, radium-226, and radium-228 were determined for water from 28 of the 39 wells, whereas gross alpha-particle activity was determined for all 39. The alpha spectroscopic technique was used to determine concentrations of radium-224, which ranged from less than 0.5 to 2.7 pCi/L with a median concentration of less than 0.5pCi/L, and of radium-226, which ranged from less than 0.5 to 3.2 pCi/L with a median concentration of less than 0.5 pCi/L. The beta-counting technique was used to determine concentrations of radium-228. The concentration of radium-228 ranged from less than 0.5 to 4.3 pCi/L with a median of less than 0.5. Radium-228, when quantifiable, had the greatest concentration of the three radium

  3. Experimental Measurement of Diffusive Extinction Depth and Soil Moisture Gradients in Southwestern Saudi Arabian Dune Sand

    KAUST Repository

    Mughal, Iqra

    2013-05-01

    In arid lands, a major contribution to water loss is by soil water evaporation. Desert sand dunes in arid regions are devoid of runoff and have high rates of infiltration. Rainwater is commonly stored within them because of the low permeability soils in the underlying desert pavement. In such cases, moisture is confined in the sand dune below a depth, termed as the “extinction depth”, where it is protected from evaporation during long dry periods. Moreover, desert sand dunes have sparse vegetation, which results in low transpiration losses from the stored water. The water accumulated below the extinction depth of the sand dunes can be utilized for various purposes such as in irrigation to support desert agriculture. In this study, field experiments were conducted in Western Saudi Arabia to monitor the soil moisture gradients and determine the diffusive extinction depth of dune sand. The dune sand was saturated with water and was exposed to natural conditions (evaporation and precipitation). The decline of the water level in the sand column was continuously recorded using transducers and sensors installed at different depths monitored the temporal variation of temperature and moisture content within the sand. The hydrological simulator HYDRUS-1D was used to construct the vertical profiles of soil water content and temperature and the results obtained from HYDRUS-1D were compared to the gradients monitored by the sensors.

  4. 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.

  5. Growth, water use efficiency, and adaptive features of the tree legume tagasaste (Chamaecytisus proliferus Link.) on deep sands in south-western Australia

    International Nuclear Information System (INIS)

    Lefroy, E. C.; Pate, J. S.

    2001-01-01

    Four-year-old tagasaste trees in dense plantation and wide-spaced alley cropping layouts at Moora, Western Australia, were cut back to 0.6 m high and their patterns of coppice regrowth and water use monitored over 3 years. Trees reached a permanent fresh watertable at 5 m depth by means of deeply penetrating sinker roots. Dry matter (DM) accumulation and transpiration loss were closely similar at the 2 planting densities despite higher soil water contents in alley plots. Yearly transpiration at plantation density amounted to 0.55 and 0.63 of Penman-Montieth potential evapotranspiration (E 0 ) in the second and third years, respectively. Mean water use efficiency over the 3 years was 247 L/kg DM, compared with values in the range 186-320 L/kg for younger pot-and column-grown trees. Using a combination of neutron moisture metre (NMM) assays of soil moisture and deuterium: hydrogen ratios of groundwater and xylem water of tagasaste and annual weeds, it was shown that trees became increasingly dependent on groundwater over time and had the capacity to switch rapidly between soil and groundwater sources. Seasonal changes in carbon isotope composition of new shoot tip dry matter indicated that plantation trees were less stressed than alley trees by the third summer as they adapted to heavy dependence on groundwater. In the third season, when plantation trees were transpiring at rates equivalent to 2.3 times annual rainfall, NMM profiles and time domain reflectometry (TDR) assays indicated that no free drainage occurred and that trees were capable of hydraulically lifting groundwater to near surface soil in the dry season. Additional adaptive features of importance to this environment included heat stress induced leaf shedding, development of perennial root nodules on lower parts of tap roots, and an ability to respond in summer to artificial irrigation or a seasonal rainfall by rapidly increasing transpiration 2-3-fold to values equalling E 0 . Copyright (2001) CSIRO

  6. Dissolution and time-dependent compaction of albite sand: experiments at 100°C and 160°C in pH-buffered organic acids and distilled water

    Science.gov (United States)

    Hajash, Andrew; Carpenter, Thomas D.; Dewers, Thomas A.

    1998-09-01

    Aqueous fluids are important in the diagenesis and deformation of crustal rocks. Both chemical and physical interactions are involved and often they are strongly coupled. For example, pore waters not only dissolve, transport, and precipitate chemical species, but they also substantially affect the mechanical behavior of the rocks that contain them. Stresses magnified at grain contacts by differences in pore-fluid pressure ( Pp) and confining pressure ( Pc) can, in turn, influence the rate and extent of chemical exchange. To begin investigation of these coupled systems, compaction experiments were conducted using albite sand (250-500 μm) and distilled water (pH 5.8), 0.07 M acetate (pH 4.7), and 0.07 M acetate + 0.005 M citrate (pH 4.4) solutions in a hydrothermal flow-through system at conditions that simulate diagenesis. Pore-fluid chemistry and pore-volume loss were monitored to quantify the effects of organic acids on time-dependent compaction rates. The effects of stress and fluid chemistry on the dissolution kinetics were also examined. Albite dissolution rates, monitored by steady-state fluid chemistry, increased when an effective pressure ( Pe= Pc- Pp) was applied, probably due to increases in total surface area caused by grain breakage at contacts. These effects were transient in distilled water, however, Si and Al concentrations remained elevated in the acetate pore fluid. The average Si-based release rates indicate ≈35% increase in reactive surface area by application of Pe=34.5 MPa. At 100°C with Pe=34.5 MPa, steady-state Si concentrations were ≈2.3 times higher in 0.07 M acetate and 5.8 times higher in 0.07 M acetate + 0.005 M citrate than in distilled water. Al increased by even larger factors (3× in the acetate buffer and 10× in the citrate solution). These changes in fluid chemistry are attributed to both pH and ligand-enhanced reactions. Albite dissolution appears to be controlled by surface complexation reactions at Al sites. Rapid

  7. Direct Chlorination of Zircon Sand

    International Nuclear Information System (INIS)

    Dwiretnani Sudjoko; Budi Sulistyo; Pristi Hartati; Sunardjo

    2002-01-01

    It was investigated the direct chlorination of zircon sand in a unit chlorination equipment. The process was in semi batch. The product gas was scrubbed in aqueous NaOH. It was search the influence of time, ratio of reactant and size of particle sand to the concentration of Zr and Si in the product. From these research it was found that as the times, ratio of reactant increased, the concentration of Zr increased, but the concentration of Si decreased, while as grain size of zircon sand decreased the concentration of Zr decreased, but the concentration of Si increased. (author)

  8. Alberta oil sands royalty regime

    International Nuclear Information System (INIS)

    Asgarpour, S.

    2004-01-01

    The long term objective of the Oil Sands Business Unit of Alberta Energy is to pave the way for Alberta's bitumen production to reach 3 million barrels per day by 2020. This presentation described the national government's role in resource development. It was emphasized that since the Crown is the owner of the oil sands resource, it would benefit by providing strategic leadership and by generating a larger royalty base. The oil sands fiscal regime was described with reference to generic royalty, risk sharing, investment, and project economics. Business rule principles were also outlined along with criteria for project expansions. Both upstream and downstream challenges and opportunities were listed. 4 figs

  9. The Rheology of Acoustically Fluidized Sand

    Science.gov (United States)

    Conrad, J. W.; Melosh, J.

    2013-12-01

    The collapse of large craters and the formation of central peaks and peak rings is well modeled by numerical computer codes that incorporate the acoustic fluidization mechanism to temporarily allow the fluid-like flow of rock debris immediately after crater excavation. Furthermore, long runout landslides require a similar mechanism to explain their almost frictionless movement, which is probably also a consequence of their granular composition coupled with internal vibrations. Many different investigators have now confirmed the ability of vibrations to fluidize granular materials. Yet it still remains to fully describe the rheology of vibrated sand as a function of stress, frequency and amplitude of the vibrations in the sand itself. We constructed a rotational viscometer to quantitatively investigate the relation between the stress and strain rate in a horizontal bed of strongly vibrated sand. In addition to the macroscopic stain rate, the amplitude and frequency of the vibrations produced by a pair of pneumatic vibrators were also measured with the aid of miniaturized piezoelectric accelerometers (B&K 4393) whose output was recorded on a digital storage oscilloscope. The initial gathering of the experimental data was difficult due to granular memory, but by having the sand compacted vibrationally for 8 minutes before each run the scatter of data was reduced and we were able to obtain consistent results. Nevertheless, our major source of uncertainty was variations in strain rate from run to run. We find that vibrated sand flows like a highly non-Newtonian fluid, in which the shear strain rate is proportional to stress to a power much greater than one, where the precise power depends on the amplitude and frequency of the applied vibrations. Rapid flow occurs at stresses less than half of the static yield stress (that is, the yield stress when no vibration is applied) when strong vibrations are present. For a Newtonian fluid, such as water, the relation between

  10. Saltation of non-spherical sand particles.

    Directory of Open Access Journals (Sweden)

    Zhengshi Wang

    Full Text Available Saltation is an important geological process and the primary source of atmospheric mineral dust aerosols. Unfortunately, no studies to date have been able to precisely reproduce the saltation process because of the simplified theoretical models used. For example, sand particles in most of the existing wind sand movement models are considered to be spherical, the effects of the sand shape on the structure of the wind sand flow are rarely studied, and the effect of mid-air collision is usually neglected. In fact, sand grains are rarely round in natural environments. In this paper, we first analyzed the drag coefficients, drag forces, and starting friction wind speeds of sand grains with different shapes in the saltation process, then established a sand saltation model that considers the coupling effect between wind and the sand grains, the effect of the mid-air collision of sand grains, and the effect of the sand grain shape. Based on this model, the saltation process and sand transport rate of non-spherical sand particles were simulated. The results show that the sand shape has a significant impact on the saltation process; for the same wind speed, the sand transport rates varied for different shapes of sand grains by as much as several-fold. Therefore, sand shape is one of the important factors affecting wind-sand movement.

  11. 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

  12. 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

  13. 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.

  14. Fusion of arkosic sand by intrusive andesite

    Science.gov (United States)

    Bailey, Roy A.

    1954-01-01

    An andesite dike in the Valles Mountains of northern New Mexico has intruded and partly fused arkosic sediments for a distance of 50 feet from its contacts. The dike is semi-circular in form, has a maximum width of about 100 feet, and is about 500 feet long. Small associated arcuate dikes are arranged in spiral fashion around the main dike, suggesting that they were intruded along shear fractures similar to those described by Burbank (1941). The fused rocks surrounding the andesite dike are of three general types: 1) partly fused arkosic sand, 2) fused clay, and 3) hybrid rocks. The fused arkosic sand consists of relict detrital grains of quartz, orthoclose, and plagioclase, imbedded in colorless glass containing microlites of tridymite, cordierite, and magnetite. The relict quartz grains are corroded and embayed by glass; the orthoclase is sanidinized and partly fused; and the plagioclase is inverted to the high temperature form and is partly fused. The fused clay, which was originally a mixture of montmorillonite and hydromica, consists primarily of cordierite but also contains needle-like crystals of sillimanite (?) or mullite (?). The hybrid rocks originated in part by intermixing of fused arkosic sediments and andesitic liquid and in part by diffusion of mafic constituents through the fused sediments. They are rich in cordierite and magnetite and also contain hypersthene, augite, and plagioclase. The composition of pigeonite in the andesite indicates that the temperature of the andesite at the time of intrusion probably did not exceed 1200?C. Samples of arkosic sand were fused in the presence of water in a Morey bomb at 1050?C. Stability relations of certain minerals in the fused sand suggest that fusion may have taken place at a lower temperature, however, and the fluxing action of volatiles from the andesite are thought to have made this possible.

  15. Namibia : triaxial test on sand

    DEFF Research Database (Denmark)

    Steenfelt, Jørgen S.; Jacobsen, Kim P.

    In connection with a harbour project the friction angle of a fine sand is required. On Friday 13 March 1998 the Danish Geotechnical Institute (DGI) delivered app. 2.5 kg sand for testing at the Geotechnical Engineering Laboratory, Aalborg University. The present Data Report summarises the results...... of two CID, isotropically consolidated, drained triaxial tests carried out according to the instructions in DG1 letter dated 13 March 1998....

  16. Fate and behavior of oil sands naphthenic acids in a pilot-scale treatment wetland as characterized by negative-ion electrospray ionization Orbitrap mass spectrometry.

    Science.gov (United States)

    Ajaero, Chukwuemeka; Peru, Kerry M; Simair, Monique; Friesen, Vanessa; O'Sullivan, Gwen; Hughes, Sarah A; McMartin, Dena W; Headley, John V

    2018-08-01

    Large volumes of oil sands process-affected water (OSPW) are generated during the extraction of bitumen from oil sands in the Athabasca region of northeastern Alberta, Canada. As part of the development of treatment technologies, molecular characterization of naphthenic acids (NAs) and naphthenic acid fraction compounds (NAFC) in wetlands is a topic of research to better understand their fate and behavior in aquatic environments. Reported here is the application of high-resolution negative-ion electrospray Orbitrap-mass spectrometry for molecular characterization of NAs and NAFCs in a non-aerated constructed treatment wetland. The effectiveness of the wetlands to remove OSPW-NAs and NAFCs was evaluated by monitoring the changes in distributions of NAFC compounds in the untreated sample and non-aerated treatment system. After correction for measured evapotranspiration, the removal rate of the classical NAs followed approximately first-order kinetics, with higher rates observed for structures with relatively higher number of carbon atoms. These findings indicate that constructed wetland treatment is a viable method for removal of classical NAs in OSPW. Work is underway to evaluate the effects of wetland design on water quality improvement, preferential removal of different NAFC species, and reduction in toxicity. Copyright © 2018. Published by Elsevier B.V.

  17. Experimental investigation on heat transport in gravel-sand materials

    DEFF Research Database (Denmark)

    Maureschat, Gerald; Heller, Alfred

    1997-01-01

    in sand-gravel material, the storage media is to be water satured. In this case, handling of such material on site is rather complex. The conduction is highly dependent on the thermal properties of the storage media and so is the overall thermal performance of a storage applying such media. For sandy...... out in a small size experiment. The experiment consists of a highly insulated box filled with two kinds of sand material crossed by a plastic heat pipe. Heat transfer is measured under dry and water satured conditions in a cross-section.The conclusions are clear. To obtain necessary heat conduction...

  18. 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.

  19. Midges (Diptera:Chironomidae) as indicators of wetland viability in the Alberta Oil Sands region

    Energy Technology Data Exchange (ETDEWEB)

    Ciborowski, J. J. H.; Whelly, M. P.; Leonhardt, C.; Laing, D. [Windsor Univ., Dept. of Biological Sciences, ON (Canada)

    1999-07-01

    Thirty-three wetlands northeast of Fort McMurray, Alberta, ten of which are receiving oil sands mine process-affected water (OSPW), have been examined to assess their biological integrity. Physico-chemical and environmental attributes were measured, sediment, zoobenthic, plankton and chlorophyll samples were analyzed. Results of principal component analysis indicated that the wetlands could be categorized into three classes on the basis of three independent combinations of environmental features, namely pH/size/dissolved oxygen; conductivity; and sediment composition. Cluster analysis identified four groups of wetlands. High conductivity wetlands were found to support greater density but reduced richness of benthic population, irrespective of the presence of OSPW. To evaluate OSPW wetland ability to support and maintain benthic populations chironomid larval morphology, density, adult emergence, flight activity, egg-laying behaviour and the ability of eggs to hatch in OSPW were monitored. Results indicated no inhibition of adult chironomid flight activity, egg-laying or hatching by OSPW, although there was some evidence of OSPW reducing chironomid density, diversity and secondary production.

  20. Experimental and numerical study on thermal conductivity of partially saturated unconsolidated sands

    Science.gov (United States)

    Lee, Youngmin; Keehm, Youngseuk; Kim, Seong-Kyun; Shin, Sang Ho

    2016-04-01

    A class of problems in heat flow applications requires an understanding of how water saturation affects thermal conductivity in the shallow subsurface. We conducted a series of experiments using a sand box to evaluate thermal conductivity (TC) of partially saturated unconsolidated sands under varying water saturation (Sw). We first saturated sands fully with water and varied water saturation by drainage through the bottom of the sand box. Five water-content sensors were integrated vertically into the sand box to monitor water saturation changes and a needle probe was embedded to measure thermal conductivity of partially saturated sands. The experimental result showed that thermal conductivity decreases from 2.5 W/mK for fully saturated sands to 0.7 W/mK when water saturation is 5%. We found that the decreasing trend is quite non-linear: highly sensitive at very high and low water saturations. However, the boundary effects on the top and the bottom of the sand box seemed to be responsible for this high nonlinearity. We also found that the determination of water saturation is quite important: the saturation by averaging values from all five sensors and that from the sensor at the center position, showed quite different trends in the TC-Sw domain. In parallel, we conducted a pore-scale numerical modeling, which consists of the steady-state two-phase Lattice-Boltzmann simulator and FEM thermal conduction simulator on digital pore geometry of sand aggregation. The simulation results showed a monotonous decreasing trend, and are reasonably well matched with experimental data when using average water saturations. We concluded that thermal conductivity would decrease smoothly as water saturation decreases if we can exclude boundary effects. However, in dynamic conditions, i.e. imbibition or drainage, the thermal conductivity might show hysteresis, which can be investigated with pore-scale numerical modeling with unsteady-state two-phase flow simulators in our future work.

  1. Effect of emplaced nZVI mass and groundwater velocity on PCE dechlorination and hydrogen evolution in water-saturated sand

    International Nuclear Information System (INIS)

    Kim, Hye-Jin; Leitch, Megan; Naknakorn, Bhanuphong; Tilton, Robert D.; Lowry, Gregory V.

    2017-01-01

    Highlights: • Reactivity of nZVI increased linearly with nZVI concentration above 10 g/L, but was non-linear below 10 g/L. • nZVI reactivity with PCE is more sensitive to solution redox potential than solution pH. • Mass transfer limits the reactivity of emplaced nZVI under typical groundwater flow velocity. • Lowering pH increases H_2 evolution from nZVI more than reactivity with PCE. • Design of nZVI remediation strategies should consider mass loading and flow velocity on performance and lifetime. - Abstract: The effect of nZVI mass loading and groundwater velocity on the tetrachloroethylene (PCE) dechlorination rate and the hydrogen evolution rate for poly(maleic acid-co-olefin) (MW = 12 K) coated nZVI was examined. In batch reactors, the PCE reaction rate constant (3.7 × 10"−"4 L hr"−"1 m"−"2) and hydrogen evolution rate constant (1.4 nanomol L hr"−"1 m"−"2) were independent of nZVI concentration above 10 g/L, but the PCE dechlorination rate decreased and the hydrogen evolution rate increased for nZVI concentration below 10 g/L. The nonlinearity between nZVI mass loading and PCE dechlorination and H_2 evolution was explained by differences in pH and E_h at each nZVI mass loading; PCE reactivity increased when solution E_h decreased, and the H_2 evolution rate increased with decreasing pH. Thus, nZVI mass loading of <5 g/L yields lower reactivity with PCE and lower efficiency of Fe° utilization than for higher nZVI mass loading. The PCE dechlorination rate increased with increasing pore-water velocity, suggesting that mass transfer limits the reaction at low porewater velocity. Overall, this work suggests that design of nZVI-based reactive barriers for groundwater treatment should consider the non-linear effects of both mass loading and flow velocity on performance and expected reactive lifetime.

  2. Effect of emplaced nZVI mass and groundwater velocity on PCE dechlorination and hydrogen evolution in water-saturated sand

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hye-Jin [Civil & Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA 15213-3890 (United States); Chemical Research Division, Environmental Health Research Department, National Institute of Environmental Research, Incheon 404-708 (Korea, Republic of); Leitch, Megan [Civil & Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA 15213-3890 (United States); Center for Environmental Implications of Nanotechnology, Carnegie Mellon University, Pittsburgh, PA 15213-3890 (United States); Naknakorn, Bhanuphong [Civil & Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA 15213-3890 (United States); Tilton, Robert D. [Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213-3890 (United States); Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213-3890 (United States); Center for Environmental Implications of Nanotechnology, Carnegie Mellon University, Pittsburgh, PA 15213-3890 (United States); Lowry, Gregory V., E-mail: glowry@cmu.edu [Civil & Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA 15213-3890 (United States); Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213-3890 (United States); Center for Environmental Implications of Nanotechnology, Carnegie Mellon University, Pittsburgh, PA 15213-3890 (United States)

    2017-01-15

    Highlights: • Reactivity of nZVI increased linearly with nZVI concentration above 10 g/L, but was non-linear below 10 g/L. • nZVI reactivity with PCE is more sensitive to solution redox potential than solution pH. • Mass transfer limits the reactivity of emplaced nZVI under typical groundwater flow velocity. • Lowering pH increases H{sub 2} evolution from nZVI more than reactivity with PCE. • Design of nZVI remediation strategies should consider mass loading and flow velocity on performance and lifetime. - Abstract: The effect of nZVI mass loading and groundwater velocity on the tetrachloroethylene (PCE) dechlorination rate and the hydrogen evolution rate for poly(maleic acid-co-olefin) (MW = 12 K) coated nZVI was examined. In batch reactors, the PCE reaction rate constant (3.7 × 10{sup −4} L hr{sup −1} m{sup −2}) and hydrogen evolution rate constant (1.4 nanomol L hr{sup −1} m{sup −2}) were independent of nZVI concentration above 10 g/L, but the PCE dechlorination rate decreased and the hydrogen evolution rate increased for nZVI concentration below 10 g/L. The nonlinearity between nZVI mass loading and PCE dechlorination and H{sub 2} evolution was explained by differences in pH and E{sub h} at each nZVI mass loading; PCE reactivity increased when solution E{sub h} decreased, and the H{sub 2} evolution rate increased with decreasing pH. Thus, nZVI mass loading of <5 g/L yields lower reactivity with PCE and lower efficiency of Fe° utilization than for higher nZVI mass loading. The PCE dechlorination rate increased with increasing pore-water velocity, suggesting that mass transfer limits the reaction at low porewater velocity. Overall, this work suggests that design of nZVI-based reactive barriers for groundwater treatment should consider the non-linear effects of both mass loading and flow velocity on performance and expected reactive lifetime.

  3. Low enthalpy geothermal for oil sands (LEGO)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    Geothermal energy is generated by the slow decay of radioactive materials within the Earth. Geothermal energy resources include the water from hot springs used for heating; the withdrawal of high temperature steam from deep wells; and the use of stable ground or water temperatures near the Earth's surface to heat or cool buildings or in industrial processes. Heat pumps are used to transfer heat or water from the ground into buildings in winter. This paper discussed low enthalpy geothermal options for oil sands processes in order to reduce the use of natural gas and emissions from greenhouse gases (GHGs). The study was also conducted to aid in the development of a portfolio of renewable energy options for the oil and gas sector. The study estimated the costs and benefits of operating a shallow geothermal borehole cluster for meeting a portion of process heat demands for the Nexen's Albian mine. The costs and benefits of operating thermo-chillers integrated with a shallow geothermal borehole cluster for waste heat mitigation were also evaluated. The study showed that geothermal designs can be used to meet a portion of oil sands process heat and cooling demands. Mining operators may reduce carbon emissions and energy costs for process heat demands by installing closed loop borehole heat exchangers. Geothermal heat storage capacity can also be used to increase the efficiency of thermal chillers. It was concluded that pilot plant studies would contribute to a better understanding of the technology. tabs., figs.

  4. Modelling assessment of oil sands pit lakes turn-over potential

    International Nuclear Information System (INIS)

    Mackenzie, I.; Vandenberg, J.; Lauzon, N.; Takyi, A.

    2006-01-01

    Pit lakes form when surface mining operations are discontinued and dewatering is terminated. Their use as a treatment step for oil sands surface mining reclamation waters was discussed. The goal of the End Pit Lake Subgroup of the Cumulative Environmental Management Association is to establish guidelines that will enable operators to achieve acceptable water quality for these lakes. Although both biological and physical processes affect turn-over potential, this presentation focused on the size of pit lakes, their depth, starting lake salinity concentrations, inflow rates and inflow salinity flux. These parameters where selected because of their influence on density gradients and turn-over potential. One-dimensional and two-dimensional modelling simulations were performed to examine turnover potential for a large range of pit lake configurations and conditions. The pit lake scenarios chosen for this modelling study included a wide range of changes in 3 lake sizes (1, 4 and 8 km 2 ), 3 lake depths (5, 20 and 50 m), 2 lake starting salinities (1 and 5 parts per thousand), 2 inflow rates (2 and 10 million m 3 per year), 3 starting inflow salinity concentrations (1, 2 and 4 parts per thousand) and 2 rates of influent salinity decrease (6- and 28- year half-life). Simulations showed that autumn is the governing season for determining turn-over potential. For the scenarios examined in this study, the expelling of salt from saline water upon ice formation and the effect of fresh water loading during spring melt events were not found to be significant factors governing turn-over potential. This presentation reviewed the DYRESM, CE-QUAL-W2, and RMA models used in this study. The conclusions reached by each model was also reviewed along with ongoing follow-up work

  5. 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.

  6. 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.

  7. Observation of sand waves in the Taiwan Banks using HJ-1A/1B sun glitter imagery

    Science.gov (United States)

    Zhang, Hua-guo; Lou, Xiu-lin; Shi, Ai-qin; He, Xie-kai; Guan, Wei-bing; Li, Dong-ling

    2014-01-01

    This study focuses on the large sand waves in the Taiwan Banks. Our goals are to observe the sand waves as completely as possible, to obtain their direction, wavelength, density, and ridge length, to analyze their spatial distributions, and to understand the effects of the current field and water depth on the sand waves. This study demonstrates the possibility of using HJ-1A/1B sun glitter imagery with a large swath width and rapid coverage in studying sand waves. Six cloud-free HJ-1A/1B optical images with sun glitter signals received during 2009 to 2011 were processed. The sand waves were mapped based on their features in the images; their direction, wavelength, density, and ridge length were measured and analyzed. We identified 4604 sand waves distributed in an area of 16,400 km2. The distributions of sand waves and their characteristics were analyzed, and the differences of sand waves between the northwestern subregion and the southeastern subregion are reported. Further analysis and discussion of the relationships between spatial distribution of the sand waves and both the tidal current field from a numerical simulation and water depth led to some interesting conclusions. The current field determines the orientation of the sand wave, while the hydrodynamic conditions and water depth influence the shape, size, and density of sand waves to a certain degree.

  8. Important processes affecting the release and migration of radionuclides from a deep geological repository

    International Nuclear Information System (INIS)

    Barátová, Dana; Nečas, Vladimír

    2017-01-01

    The processes that affect significantly the transport of contaminants through the near field and far field of a deep geological repository of spent nuclear fuel were studied. The processes can be generally divided into (i) processes related to the release of radionuclides from the spent nuclear fuel; (ii) processes related to the radionuclide transport mechanisms (such as advection and diffusion); and (iii) processes affecting the rate of radionuclide migration through the multi-barrier repository system. A near-field and geosphere model of an unspecified geological repository sited in a crystalline rock is also described. Focus of the treatment is on the effects of the different processes on the activity flow of the major safety-relevant radionuclides. The activity flow was simulated for one spent fuel cask by using the GoldSim simulation tool. (orig.)

  9. Effect of Partial Replacement of Sand With Quarry Dust on the ...

    African Journals Online (AJOL)

    This work investigated the effect of partial replacement of sand with quarry dust on the compressive strength, flexural strength, split tensile strength and water absorption of sandcrete blocks. River sand was replaced with quarry dust at percentages ranging from 0 to 40 at cement/combined aggregate ratio of 1: 6. The blocks ...

  10. The Soil-Land use System in a Sand Spit Area in the Semi-Arid ...

    African Journals Online (AJOL)

    The Soil-Land use System in a Sand Spit Area in the Semi-Arid Coastal Savanna Region of Ghana – Development, Sustainability and Threats. ... The investigation comprises soil profile descriptions and analyses on the dominant soil type on the sand spit, measurement of electrical conductivity of well water and in the soil, ...

  11. Ice processes affect habitat use and movements of adult cutthroat trout and brook trout in a Wyoming foothills stream

    Science.gov (United States)

    Lindstrom, J.W.; Hubert, W.A.

    2004-01-01

    Habitat use and movements of 25 adult cutthroat trout Oncorhynchus clarkii and 25 adult brook trout Salvelinus fontinalis from fall through winter 2002-2003 were assessed by means of radiotelemetry in a 7-km reach of a Rocky Mountains foothills stream. Temporal dynamics of winter habitat conditions were evaluated by regularly measuring the features of 30 pools and 5 beaver Castor canadensis ponds in the study reach. Groundwater inputs at three locations raised mean daily water temperatures in the stream channel during winter to 0.2-0.6??C and kept at least 250 m of the downstream channel free of ice, but the lack of surface ice further downstream led to the occurrence of frazil ice and anchor ice in pools and unstable habitat conditions for trout. Pools in segments that were not affected by groundwater inputs and beaver ponds tended to be stable and snow accumulated on the surface ice. Pools throughout the study reach tended to become more stable as snow accumulated. Both cutthroat trout and brook trout selected beaver ponds as winter progressed but tended to use lateral scour pools in proportion to their availability. Tagged fish not in beaver ponds selected lateral scour pools that were deeper than average and stable during winter. Movement frequencies by tagged fish decreased from fall through winter, but some individuals of both species moved during winter. Ice processes affected both the habitat use and movement patterns of cutthroat trout and brook trout in this foothills stream.

  12. Sands at Gusev Crater, Mars

    Science.gov (United States)

    Cabrol, Nathalie A.; Herkenhoff, Kenneth E.; Knoll, Andrew H.; Farmer, Jack D.; Arvidson, Raymond E.; Grin, E.A.; Li, Ron; Fenton, Lori; Cohen, B.; Bell, J.F.; Yingst, R. Aileen

    2014-01-01

    Processes, environments, and the energy associated with the transport and deposition of sand at Gusev Crater are characterized at the microscopic scale through the comparison of statistical moments for particle size and shape distributions. Bivariate and factor analyses define distinct textural groups at 51 sites along the traverse completed by the Spirit rover as it crossed the plains and went into the Columbia Hills. Fine-to-medium sand is ubiquitous in ripples and wind drifts. Most distributions show excess fine material, consistent with a predominance of wind erosion over the last 3.8 billion years. Negative skewness at West Valley is explained by the removal of fine sand during active erosion, or alternatively, by excess accumulation of coarse sand from a local source. The coarse to very coarse sand particles of ripple armors in the basaltic plains have a unique combination of size and shape. Their distribution display significant changes in their statistical moments within the ~400 m that separate the Columbia Memorial Station from Bonneville Crater. Results are consistent with aeolian and/or impact deposition, while the elongated and rounded shape of the grains forming the ripples, as well as their direction of origin, could point to Ma'adim Vallis as a possible source. For smaller particles on the traverse, our findings confirm that aeolian processes have dominated over impact and other processes to produce sands with the observed size and shape patterns across a spectrum of geologic (e.g., ripples and plains soils) and aerographic settings (e.g., wind shadows).

  13. Study on hardness and microstructural characteristics of sand cast ...

    Indian Academy of Sciences (India)

    Administrator

    casting in green sand molds at 690°C. The solution treatment has been performed at 500°C for 7 h and then ... that specimens were water quenched to obtain super satu- ... structure and (b) distribution of silicon platelets (grey) and fine.

  14. Holocene beach buildup and coastal aeolian sand incursions off the Nile littoral cell

    Science.gov (United States)

    Roskin, Joel; Sivan, Dorit; Shtienberg, Gilad; Porat, Naomi; Bookman, Revital

    2017-04-01

    Israel's coastal plain is abundant with sand originating from the Nile littoral cell. The inland windblown loose sand has formed 3-6 km wide lobe-like sand and dune fields currently comprised of foredunes, linear and northeasterly facing transverse and parabolic dunes that are currently stabilized by vegetation. This study reviews the architecture and history of the these dune fields aiming to: (a) Date the timings of beach accretion, and sand and dune incursions. (b) Discriminate between natural and human-induced forcing factors of sand mobilization and stabilization in time and space. (c) Present a model of the dunescape development. (d) Assess scenarios of sand transport in the future charcaterized by intense human impact and climate change. Luminescence ages, radiocarbon dates and relative ages from previously published geological and archaeological reports, historical texts, together with new optically stimulated luminescence (OSL) ages and stratigraphic and sedimentological data are analyzed. The deposition, mobilizations and preservation of the sand bodies, initially induced by the decline in sea level rise at 6-4 ka, were later controlled by historic land-use intensity and modern land-use/negligence practices. At 6 ka, beach sand buildup rapidly started. Where aeolianite ridges bordered the coast, pulses of sand with biogenic carbonate grains unconformably draped the ridges and rapidly consolidated into a distinct sandy calcarenite unit. Further east, sand sheets and low dunes partly pedogenized following their incursion, but did not cement. The water retention capacities of the sand sheets enabled the establishment of a sand-stabilizing vegetation cover that probably became an attractive environment for fuel and grazing. The growing Hellenistic-Roman-Byzantine ( 2.4-1.3 ka) populations probably led to increased consumption and massive destruction of sand stabilizing vegetation, enabling sand erodibility and mobilization during winter storms. The sand

  15. Phase behavior of methane hydrate in silica sand

    International Nuclear Information System (INIS)

    Sun, Shi-Cai; Liu, Chang-Ling; Ye, Yu-Guang; Liu, Yu-Feng

    2014-01-01

    Highlights: • Hydrate p-T trace in coarse-grained sediment is consistent with that in bulk water. • Fine-grained sediment affects hydrate equilibrium for the depressed water activity. • Hydrate equilibrium in sediment is related to the pore size distribution. • The application of hydrate equilibrium in sediment depends on the actual condition. -- Abstract: Two kinds of silica sand powder with different particle size were used to investigate the phase behavior of methane hydrate bearing sediment. In coarse-grained silica sand, the measured temperature and pressure range was (281.1 to 284.2) K and (5.9 to 7.8) MPa, respectively. In fine-grained silica sand, the measured temperature and pressure range was (281.5 to 289.5) K and (7.3 to 16.0) MPa, respectively. The results show that the effect of coarse-grained silica sand on methane hydrate phase equilibrium can be ignored; however, the effect of fine-grained silica sand on methane hydrate phase equilibrium is significant, which is attributed to the depression of water activity caused by the hydrophilicity and negatively charged characteristic of silica particle as well as the pore capillary pressure. Besides, the analysis of experimental results using the Gibbs–Thomson equation shows that methane hydrate phase equilibrium is related to the pore size distribution of silica sand. Consequently, for the correct application of phase equilibrium data of hydrate bearing sediment, the geological condition and engineering requirement should be taken into consideration in gas production, resource evaluation, etc

  16. Faunistic assemblages of a sublittoral coarse sand habitat of the northwestern Mediterranean

    Directory of Open Access Journals (Sweden)

    Eva Pubill

    2011-02-01

    Full Text Available The sublittoral megabenthic assemblages of a northwestern Mediterranean coarse sandy beach exploited for the bivalve Callista chione were studied. The spatial and bathymetric variability of its distinctive faunal assemblages was characterised by quantitative sampling performed with a clam dredge. The taxa studied were Mollusca Bivalvia and Gastropoda, Crustacea Decapoda, Echinodermata and Pisces, which accounted for over 99% of the total biomass. Three well-differentiated species assemblages were identified: (1 assemblage MSS (Medium Sand Shallow in medium sand (D50=0.37 mm and shallow waters (mean depth =6.5 m, (2 assemblage CSS (Coarse Sand Shallow in coarse sand (D50=0.62 mm in shallow waters (mean depth =6.7 m, and (3 assemblage CSD (Coarse Sand Deep in coarse sand (D50=0.64 mm in deeper waters (mean depth =16.2 m. Assemblage MSS was characterised by the codominance of the bivalves Mactra stultorum and Acanthocardia tuberculata. C. chione was dominant in both density and biomass in assemblages CSS and CSD. The occurrence of the crab Thia scutellata also characterised assemblage CSS, whereas the occurrence of the sea urchin Echinocardium mediterraneum characterised assemblage CSD. A depth breaking point of around 10 m determined the discontinuity between assemblages CSS and CSD, which was related to the closure depth of the beaches in the study area. Species richness was highest in the coarse sand communities; however, Shannon-Wiener diversity and Pielou equitability indexes were higher in the shallow fine sand community.

  17. An Investigation into the Use of Manufactured Sand as a 100% Replacement for Fine Aggregate in Concrete.

    Science.gov (United States)

    Pilegis, Martins; Gardner, Diane; Lark, Robert

    2016-06-02

    Manufactured sand differs from natural sea and river dredged sand in its physical and mineralogical properties. These can be both beneficial and detrimental to the fresh and hardened properties of concrete. This paper presents the results of a laboratory study in which manufactured sand produced in an industry sized crushing plant was characterised with respect to its physical and mineralogical properties. The influence of these characteristics on concrete workability and strength, when manufactured sand completely replaced natural sand in concrete, was investigated and modelled using artificial neural networks (ANN). The results show that the manufactured sand concrete made in this study generally requires a higher water/cement (w/c) ratio for workability equal to that of natural sand concrete due to the higher angularity of the manufactured sand particles. Water reducing admixtures can be used to compensate for this if the manufactured sand does not contain clay particles. At the same w/c ratio, the compressive and flexural strength of manufactured sand concrete exceeds that of natural sand concrete. ANN proved a valuable and reliable method of predicting concrete strength and workability based on the properties of the fine aggregate (FA) and the concrete mix composition.

  18. An Investigation into the Use of Manufactured Sand as a 100% Replacement for Fine Aggregate in Concrete

    Directory of Open Access Journals (Sweden)

    Martins Pilegis

    2016-06-01

    Full Text Available Manufactured sand differs from natural sea and river dredged sand in its physical and mineralogical properties. These can be both beneficial and detrimental to the fresh and hardened properties of concrete. This paper presents the results of a laboratory study in which manufactured sand produced in an industry sized crushing plant was characterised with respect to its physical and mineralogical properties. The influence of these characteristics on concrete workability and strength, when manufactured sand completely replaced natural sand in concrete, was investigated and modelled using artificial neural networks (ANN. The results show that the manufactured sand concrete made in this study generally requires a higher water/cement (w/c ratio for workability equal to that of natural sand concrete due to the higher angularity of the manufactured sand particles. Water reducing admixtures can be used to compensate for this if the manufactured sand does not contain clay particles. At the same w/c ratio, the compressive and flexural strength of manufactured sand concrete exceeds that of natural sand concrete. ANN proved a valuable and reliable method of predicting concrete strength and workability based on the properties of the fine aggregate (FA and the concrete mix composition.

  19. Heavy mineral sorting as a tool to distinguish depositional characteristics of “in situ” sands from their related injected sands in a Palaeogene submarine Canyon, Danish North Sea

    DEFF Research Database (Denmark)

    Moatari Kazerouni, Afsoon; Friis, Henrik; Svendsen, Johan. B

    Postdepositional remoblization and injection of sand are important processes in deep-water clastic systems. Subsurface mobilisation and injection of sand has been recently recognised as a significant control of deep-water sandstone geometry. Kilometre-scale injection complexes have been interpreted...

  20. Radiometric Characterization of Sand in Northeast Sinai

    International Nuclear Information System (INIS)

    Ramadan, Kh.A.; Badran, H.M.; Ramadan, Kh.A.; Seddeek, M.K.; Sharshar, T.

    2009-01-01

    Thirty-eight locations covering an area of 350 km 2 in northeast Sinai were investigated by gamma-ray spectroscopy using a 50% HPGe detector. The limits of area are Al-Arish North, El-Hasana South, El-Oga East, and El- Gifgafa West. The range of activity concentrations of 238 U, 234 Th, 226 Ra, 232 Th and 40 K are 0.6-35.2, 3.9-22.6, 4.7-29.6, 4.7-23.9, and 108-295 Bq/kg for sands, respectively. 137 Cs in the region ranged from 0.1-8.0 Bq/kg. No major difference between the studied area and that previously investigated in the costal area in North Sinai. Reliable correlations (R2 = 0.8-0.9) among 238 U, 234 Th, and 226 Ra isotopes was obtained. On the other hand, low correlation (R 2 = 0.6-0.7) was obtained from the analysis of the isotopes of 238 U-seies and 232 Th. No evidence of correlation between the concentrations of radioisotopes and pH contents, TOM, and grain size were found. The soil-plant transfer factor are 226 Ra and 232 Th, 40 K, and 137 Cs, respectively. The wild vegetations collected from the studied area have average concentrations of 1.9, 1.4, 1.3, 254, and 0.3 for 234 Th, 226 Ra, 232 Th, 40 K, and 137 Cs, respectively. The average concentrations of 226 Ra, 232 Th, and 40 K in water samples collected from five wells are 0.02, 0.02, and 1.1 Bq/l, respectively. The average absorbed dose rate for the sand samples were calculated to be 19.4 n Gy h-1. The Raeq activities of the sands are lower than the recommended maximum value of 370 Bq kg-1 criterion limit of Raeq activity for building materials

  1. Geology on a Sand Budget

    Science.gov (United States)

    Kane, Jacqueline

    2004-01-01

    Earth science teachers know how frustrating it can be to spend hundreds of dollars on three-dimensional (3-D) models of Earth's geologic features, to use the models for only a few class periods. To avoid emptying an already limited science budget, the author states that teachers can use a simple alternative to the expensive 3-D models--sand. She…

  2. Engaging Canadians: national oil sands dialogues - A background paper

    International Nuclear Information System (INIS)

    Carson, Bruce

    2010-01-01

    It is expected that the world's energy demand will grow significantly between now and the year 2050. Hydrocarbons will have an important role to play in meeting this increasing demand and unconventional sources such as oil sands will become more and more important. The Canadian Association of Petroleum Producers (CAPP) has been engaged in a dialogue process to examine the environmental, economic and social impacts of the oil sands industry and the aim of this background paper is to provide stakeholders with some context. The paper highlights the fact that although the oil sands industry gives rise to environmental issues such as greenhouse gas emissions, air pollutants, land disturbance and water use, the environmental performance of the industry has been improving in recent years thanks to new technologies.

  3. Interactions between microbial activity and distribution and mineral coatings on sand grains from rapid sand filters treating groundwater

    DEFF Research Database (Denmark)

    Gülay, Arda; Tatari, Karolina; Musovic, Sanin

    Rapid sand filtration is a traditional and widespread technology for drinking water purification which combines biological, chemical and physical processes together. Granular media, especially sand, is a common filter material that allows several oxidized compounds to accumulate on its surface....... Preliminarily, we detected a strong relation between the amount of DNA and mineral coating mass. We hypothesized that the accumulated mineral coatings have a positive effect on amount of bacterial biomass, its spatial distribution and substrate removal rates. In this study, we combined molecular, microscopic...

  4. [Preliminary Study of Lonicera hypoglauca on Germination Conditions of Sand Culture Seeds and Sterilization Method of Sand Culture Seedling Sterilization].

    Science.gov (United States)

    Tan, Mu-xiu; Zeng, Wen-wen; Wei, Peng-xiao; Mo, Qiao-cheng; Pu, Zu-ning; Cen, Xiu-fen; Shi, Feng-hua

    2015-05-01

    To explore the germination conditions of Lonicera hypoglauca sand culture seeds and the effects of sand culture seedlings sterilization. 0.1% HgCl2 with different sterilization time, different illumination time and temperature culture condition were adopted to study the germination conditions of sand culture seeds. Different sterilization treatments and different hardening-seedling days were used to test the sterilization effect of sand culture seedlings. The sterilization effect of the combination of 75% ethanol 30 s + 0.1% HgCl2 5 min on Lonicera hypoglauca seeds was the optimum,with the average pollution rate of 15.56%, and the average germination rate reached 51.11%. The combination of varied temperature-room temperature under light for 12 h/d was the best, with the average germination rate peaked at 75.49%, and the average germination potential reached 68.36%. The treatment of detergent liquor scrub-tap water wash on the part above the hypocotyl, which was sand cultured under the opening condition and had no root, showed the best sterilization effect, with the average pollution rate was zero, and the average survival rate peaked at 100.00%. The sterilization effect of sand culture seedlings, which was disinfected after cleaning by detergent liquor scrub-tap water wash after hardening-seeding for 30 days, was the best, with the average pollution rate of 50.00%, and the average survival rate of 100.00%. The best sterilization effect is the combination of 75% ethanol 30 s + 0.1% HgCl2 5 min; Lighting for 12 h/d of varied temperature-room temperature is regarded as the optimum culture condition. The treatment of detergent liquor scrub-tap water wash treatment on the part above the hypocotyl,which is sand cultured under the opening condition and had no root, shows the best sterilization effect. For the sand culture seedlings, before inoculated in subculture medium, should be hardening-seedling for some days and sterilized after detergent liquor scrub-tap water wash.

  5. 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.

  6. 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

  7. Improving the geotechnical behavior of sand through cohesive admixtures

    Directory of Open Access Journals (Sweden)

    Mohie eldin Mohamed Afify Elmashad

    2018-04-01

    Full Text Available Irrigation projects in Egypt have been facing tremendous challenges, mostly is the scarcity of irrigation water. The current research presents the effect of different cohesive admixture on the conductivity of siliceous sand in general and its other geotechnical properties. Two different types of conventional swelling clay from (Toshka, 6th of October as well as bentonite were used to construct the irrigation canals and embankment. The results indicated that increase in the plasticity properties of the treated soil also decrease the permeability and infiltration. Moreover, the dry density of 2.08 t/m3 was obtained from sand and 20% 6th of October mixture, also the CBR of 31.20% were obtained from sand and 8% 6th of October mixture. Increasing the bentonite ratio increases the cohesion and decreasing the permeability. The swelling ratios of sand 6th of October Clay mixture is equal to 0.28%, and the fictitious stress at which the swelling ratio is nil, is equal to 16 kPa. Keywords: Sand, Swelling clay, Bentonite, Compaction test, Consolidation test, Triaxial test

  8. Saskatchewan's place in the Canadian oil sands

    Energy Technology Data Exchange (ETDEWEB)

    Schramm, L.L. [Saskatchewan Research Council, Saskatoon, SK (Canada); Kramers, J.W. [Owl Ventures Inc., Edmonton, AB (Canada); Isaacs, E.E. [Alberta Energy Research Inst., Calgary, AB (Canada)

    2009-07-01

    This paper provided a detailed description of the oil sands geology and physical properties and highlighted some of the novel recovery technologies that are being developed for shallow in-situ reservoirs in Alberta and Saskatchewan. Canada's oil sands are well known around the world, with Alberta's mined and in-situ oil sands reservoirs being well developed with mature commercial technologies. Shallow in-situ oil sands located in both Saskatchewan and Alberta will be the next frontier in Canadian petroleum development. Shallow reservoirs will need to be developed with new environmentally sound in-situ technologies that will reduce the use of steam and fresh water, and also reduce greenhouse gas emissions. Research and development programs are currently underway to develop and demonstrate such new technologies. It was concluded that innovation has been the key to developing the immense and complex technology oil contained in Canada's heavy oil reservoirs and also in its shallow and deep in-situ oil sands reservoirs. Promising technologies include the solvent vapour extraction and hybrid thermal solvent extraction processes that are being developed and demonstrated in large-scale three-dimensional scaled physical models and associated numerical simulation models. Electrical heating and gravity stable combustion are other examples of technologies that could play a significant role in developing these resources. 88 refs., 3 tabs., 8 figs.

  9. Retempering of Concrete made by using Manufactured Sand

    Science.gov (United States)

    Pethkar, A. R.; Deshmukh, G.

    2014-06-01

    Retempering is defined as, " Addition of water and remixing of concrete or mortar which has lost enough workability to become unplaceable". Retempering inevitably results in some loss of strength compared with the original concrete [1]. Adding water to a plastic mix to increase slump is an extremely common practice, even though it is not recommended because it increases the porosity of concrete. Concrete often arrives on site more than half an hour after initial mixing. Placement operations can take anywhere from 10 to 60 min, depending on the field conditions and the size of the load. When the slump decreases to an unacceptable level during the operations, water is added to the mix [1]. In this work, an attempt is made to study the strength characteristics of retempered concrete made by using manufactured sand. Usually the retempering process is there with normal and ready mixed concrete; hence an attempt is made to check the compressive and flexural strength of normal retempered concrete with an addition of retarder 0.2, 0.4 and 0.6 % at retempering time from 15 to 90 min. There is scarcity of natural sand due to various factors, which is replaced by the manufactured sand. The concept of manufactured sand is nothing but breaking stone into smaller and smaller particles in such way that the gradation of particle will match with zone-II of I.S.

  10. A model for evaluating effects of climate, water availability, and water management on wetland impoundments--a case study on Bowdoin, Long Lake, and Sand Lake National Wildlife Refuges

    Science.gov (United States)

    Tangen, Brian A.; Gleason, Robert A.; Stamm, John F.

    2013-01-01

    Many wetland impoundments managed by the U.S. Fish and Wildlife Service (USFWS) National Wildlife Refuge System throughout the northern Great Plains rely on rivers as a primary water source. A large number of these impoundments currently are being stressed from changes in water supplies and quality, and these problems are forecast to worsen because of projected changes to climate and land use. For example, many managed wetlands in arid regions have become degraded owing to the long-term accumulation of salts and increased salinity associated with evapotranspiration. A primary goal of the USFWS is to provide aquatic habitats for a diversity of waterbirds; thus, wetland managers would benefit from a tool that facilitates evaluation of wetland habitat quality in response to current and anticipated impacts of altered hydrology and salt balances caused by factors such as climate change, water availability, and management actions. A spreadsheet model that simulates the overall water and salinity balance (WSB model) of managed wetland impoundments is presented. The WSB model depicts various habitat metrics, such as water depth, salinity, and surface areas (inundated, dry), which can be used to evaluate alternative management actions under various water-availability and climate scenarios. The WSB model uses widely available spreadsheet software, is relatively simple to use, relies on widely available inputs, and is readily adaptable to specific locations. The WSB model was validated using data from three National Wildlife Refuges with direct and indirect connections to water resources associated with rivers, and common data limitations are highlighted. The WSB model also was used to conduct simulations based on hypothetical climate and management scenarios to demonstrate the utility of the model for evaluating alternative management strategies and climate futures. The WSB model worked well across a range of National Wildlife Refuges and could be a valuable tool for USFWS

  11. Experimental study of optimal self compacting concrete with spent foundry sand as partial replacement for M-sand using Taguchi approach

    Directory of Open Access Journals (Sweden)

    Nirmala D.B.

    2016-06-01

    Full Text Available This paper presents the application of Taguchi approach to obtain optimal mix proportion for Self Compacting Concrete (SCC containing spent foundry sand and M-sand. Spent foundry sand is used as a partial replacement for M-sand. The SCC mix has seven control factors namely, Coarse aggregate, M-sand with Spent Foundry sand, Cement, Fly ash, Water, Super plasticizer and Viscosity modifying agent. Modified Nan Su method is used to proportion the initial SCC mix. L18 (21×37 Orthogonal Arrays (OA with the seven control factors having 3 levels is used in Taguchi approach which resulted in 18 SCC mix proportions. All mixtures are extensively tested both in fresh and hardened states to verify whether they meet the practical and technical requirements of SCC. The quality characteristics considering “Nominal the better” situation is applied to the test results to arrive at the optimal SCC mix proportion. Test results indicate that the optimal mix satisfies the requirements of fresh and hardened properties of SCC. The study reveals the feasibility of using spent foundry sand as a partial replacement of M-sand in SCC and also that Taguchi method is a reliable tool to arrive at optimal mix proportion of SCC.

  12. Experimental study of optimal self compacting concrete with spent foundry sand as partial replacement for M-sand using Taguchi approach

    Science.gov (United States)

    Nirmala, D. B.; Raviraj, S.

    2016-06-01

    This paper presents the application of Taguchi approach to obtain optimal mix proportion for Self Compacting Concrete (SCC) containing spent foundry sand and M-sand. Spent foundry sand is used as a partial replacement for M-sand. The SCC mix has seven control factors namely, Coarse aggregate, M-sand with Spent Foundry sand, Cement, Fly ash, Water, Super plasticizer and Viscosity modifying agent. Modified Nan Su method is used to proportion the initial SCC mix. L18 (21×37) Orthogonal Arrays (OA) with the seven control factors having 3 levels is used in Taguchi approach which resulted in 18 SCC mix proportions. All mixtures are extensively tested both in fresh and hardened states to verify whether they meet the practical and technical requirements of SCC. The quality characteristics considering "Nominal the better" situation is applied to the test results to arrive at the optimal SCC mix proportion. Test results indicate that the optimal mix satisfies the requirements of fresh and hardened properties of SCC. The study reveals the feasibility of using spent foundry sand as a partial replacement of M-sand in SCC and also that Taguchi method is a reliable tool to arrive at optimal mix proportion of SCC.

  13. Parcperdue geopressure-geothermal project. Study a geopressured reservoir by drilling and producing a well in a limited geopressured water sand. Final technical report, September 28, 1979-December 31, 1983

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, J.R.; Stanley, J.G. (eds.)

    1984-01-15

    The behavior of geopressured reservoirs was investigated by drilling and producing a well in small, well defined, geopressured reservoir; and performing detailed pressure transient analysis together with geological, geophysical, chemical, and physical studies. The Dow-DOE L. R. Sweezy No. 1 well was drilled to a depth of 13,600 feet in Parcperdue field, just south of Lafayette, Louisiana, and began production in April, 1982. The production zone was a poorly consolidated sandstone which constantly produced sand into the well stream, causing damage to equipment and causing other problems. The amount of sand production was kept manageable by limiting the flow rate to below 10,000 barrels per day. Reservoir properties of size, thickness, depth, temperature, pressure, salinity, porosity, and permeability were close to predicted values. The reservoir brine was undersaturated with respect to gas, containing approximately 20 standard cubic feet of gas per barrel of brine. Shale dewatering either did not occur or was insignificant as a drive mechanism. Production terminated when the gravel-pack completion failed and the production well totally sanded in, February, 1983. Total production up to the sanding incident was 1.94 million barrels brine and 31.5 million standard cubic feet gas.

  14. Effects of artificial sand fixing on community characteristics of a rare desert shrub.

    Science.gov (United States)

    Liu, Huiliang; Tao, Ye; Qiu, Dong; Zhang, Daoyuan; Zhang, Yongkuan

    2013-10-01

    Eremosparton songoricum (Fabaceae) is a rare, native, clonal small shrub of the deserts of central Asia. Although human activities have greatly fragmented the distribution of E. songoricum, it occurs in areas where artificial sand fixing (AS) has been implemented. We sought to explore whether AS promotes survival and growth of E. songoricum. In the Gurbantunggut Desert of northwestern China in June 2010, we established 10 plots in an area where sand fixing occurred (5-10 years previously) and 11 plots on original sand substrate on which some plants had settled without fixing sand. Sand fixing changed soil properties and biological characteristics in sand-fixed plots. The soil surface where sand fixing occurred was covered by algal crusts and some lichen, but not bare sand (BS). Soil nutrients; water content of deep soil (30-150 cm); overall plant and herbaceous species richness, diversity, abundance, and cover; above- and belowground biomass; and cover, biomass, and height of E. songoricum in the sand-fixed plots were significantly greater than in plots of BS. However, distribution of E. songoricum individuals in the 2 types of plots did not differ. Our results indicate AS may enhance survival of E. songoricum and increase the overall diversity and stability of the desert plant community. We suggest AS as a way to protect this rare desert plant in situ. © 2013 Society for Conservation Biology.

  15. Tidal dynamics in the sand motor lagoon

    NARCIS (Netherlands)

    De Vries, S.; Radermacher, M.; De Schipper, M.A.; Stive, M.J.F.

    2015-01-01

    The Sand Motor is a mega-nourishment characterized by a very large sand volume of around 20 million m3 placed along the Dutch coast. The Sand Motor is a pilot project to evaluate the performance of an alternative nourishment strategy with respect to different functions of the coastal system. Within

  16. Holocene marine transgression as interpreted from bathymetry and sand grain size parameters off Gopalpur

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, K.M.; Rajamanickam, G.V.; Rao, T.C.S.

    Grain size statistical parameters of the surface sediment samples collected from the innershelf off Gopalpur were calculated using graphic and moment methods. Fine-grained sand present up to 15 m water depth shows symmetrical skewness and good...

  17. Study on the Permeability Characteristics of Polyurethane Soil Stabilizer Reinforced Sand

    Directory of Open Access Journals (Sweden)

    Jin Liu

    2017-01-01

    Full Text Available A polymer material of polyurethane soil stabilizer (PSS is used to reinforce the sand. To understand the permeability characteristics of PSS reinforced sand, a series of reinforcement layer form test, single-hole permeability test, and porous permeability test of sand reinforced with PSS have been performed. Reinforcement mechanism is discussed with scanning electron microscope images. The results indicated that the permeability resistance of sand reinforced with polyurethane soil stabilizer is improved through the formation of reinforcement layer on the sand surface. The thickness and complete degree of the reinforcement layer increase with the increasing of curing time and PSS concentration. The water flow rate decreases with the increasing of curing time or PSS concentration. The permeability coefficient decreases with the increasing of curing time and PSS concentration and increases with the increasing of depth in specimen. PSS fills up the voids of sand and adsorbs on the surface of sand particle to reduce or block the flowing channels of water to improve the permeability resistance of sand. The results can be applied as the reference for chemical reinforcement sandy soil engineering, especially for surface protection of embankment, slope, and landfill.

  18. Mecoprop (MCPP) removal in full-scale rapid sand filters at a groundwater-based waterworks

    DEFF Research Database (Denmark)

    Hedegaard, Mathilde Jørgensen; Arvin, Erik; Corfitzen, Charlotte B.

    2014-01-01

    and secondary rapid sand filters. Water quality parameters were measured throughout the waterworks, and they behaved as designed for. MCPP was removed in secondary rapid sand filters — removal was the greatest in the sand filters in the filter line with the highest contact time (63min). In these secondary sand...... in the full-scale system. Therefore, microcosms were set up with filter sand, water and 14C-labelled MCPP at an initial concentration of 0.2μg/L. After 24h, 79–86% of the initial concentration of MCPP was removed. Sorption removed 11–15%, while the remaining part was removed by microbial processes, leading...... to a complete mineralisation of 13–18%. Microbial removal in the filter sand was similar at different depths of the rapid sand filter, while the amount of MCPP which adsorbed to the filter sand after 48h decreased with depth from 21% of the initial MCPP in the top layer to 7% in the bottom layer...

  19. Intermontane eolian sand sheet development, Upper Tulum Valley, central-western Argentina

    Directory of Open Access Journals (Sweden)

    Patrick Francisco Fuhr Dal' Bó

    Full Text Available ABSTRACTThe intermontane Upper Tulum eolian sand sheet covers an area of ca. 125 km² at north of the San Juan Province, central-western Argentina. The sand sheet is currently an aggrading system where vegetation cover, surface cementation and periodic flooding withhold the development of dunes with slipfaces. The sand sheet surface is divided into three parts according to the distribution of sedimentary features, which reflects the variation in sediment budget, water table level and periodic flooding. The central sand sheet part is the main area of eolian deposition and is largely stabilized by vegetation. The sedimentary succession is 4 m thick and records the vertical interbedding of eolian and subaqueous deposits, which have been deposited for at least 3.6 ky with sedimentation rates of 86.1 cm/ky. The construction of the sand sheet is associated with deflation of the sand-graded debris sourced by San Juan alluvial fan, which is available mainly in drier fall-winter months where water table is lower and wind speeds are periodically above the threshold velocity for sand transport. The accumulation of sedimentary bodies occurs in a stabilized eolian system where vegetation cover, thin mud veneers and surface cementation are the main agents in promoting accumulation. The preservation of the sand sheet accumulations is enabled by the progressive creation of the accommodation space in a tectonically active basin and the continuous burial of geological bodies favored by high rates of sedimentation.

  20. The Suitability Of Local Quartz Sand In The Production Of Bath Crucibles.

    Directory of Open Access Journals (Sweden)

    C. O. Okpanachi

    2017-03-01

    Full Text Available The suitability of local quartz sand in the production of bath crucibles is a study that was carried out in order to impart overall strength on bath crucibles hence reduce breakages during fettling. Therefore this research constitutes a study to enhance the efficiency of production of bath crucibles by addition of quartz sand in slip preparation. The steps taken in the beneficiation of quartz sand for the production of bath crucibles are comminution which entails crushing and milling classification washing liquid dispersion sizing and reduction of iron content by magnetic separation. The slip contains materials like plastic clay feldspar kaolin talc sodium silicate water quartz sand etc. These were all milled in the ball mill for slip production casting and fettling glazing and sintering to get final bath crucibles as the end products. Quartz sand is used in a variety of products essentially as raw material for the foundry casting and glass industries and also in chemicals water filtration and ceramics the heat resistance nature of quartz sand makes it an excellent refractory substance for these industrial processes. Slip can be prepared for production of bath crucibles without the inclusion of quartz sand however the addition of quartz sand is needed to improve the mechanical performance of the slip in the production of bath crucibles.

  1. An Investigation for Disposal of Drill Cuttings into Unconsolidated Sandstones and Clayey Sands

    Energy Technology Data Exchange (ETDEWEB)

    Mese, Ali; Dvorkin, Jack; Shillinglaw, John

    2000-09-11

    This project include experimental data and a set of models for relating elastic moduli/porosity/texture and static-to-dynamic moduli to strength and failure relationships for unconsolidated sands and clayey sands. The results of the project should provide the industry with a basis for wider use of oil base drilling fluids in water sensitive formations by implementing drill cutting injection into existing wells at abandoned formations and controlling fracture geometry to prevent ground water contamination.

  2. Study of transport in unsaturated sands using radioactive tracers

    International Nuclear Information System (INIS)

    Merritt, W.F.; Pickens, J.F.; Allison, G.B.

    1979-01-01

    A laboratory experiment was conducted to investigate the mixing that occurs as a series of labelled pulses of water are transported by gravity drainage down through a sand filled column having a water table imposed at the bottom. It also demonstrated the utility of gamma-ray emitting radioactive tracers in studying transport in unsaturated or saturated porous media. The motivation for pursuing this topic was developed from observing that the content of oxygen-18, deuterium and tritium in rainwater shows marked temporal variations whereas their concentrations below the water table in shallow ground water flow systems are generally found to show much less variation. (auth)

  3. METHOD OF PROCESSING MONAZITE SAND

    Science.gov (United States)

    Welt, M.A.; Smutz, M.

    1958-08-26

    A process is described for recovering thorium, uranium, and rare earth values from monazite sand. The monazite sand is first digested with sulfuric acid and the resulting "monazite sulfate" solution is adjusted to a pH of between 0.4 and 3.0, and oxalate anions are added causing precipitation of the thorium and the rare earths as the oxalates. The oxalate precipitate is separated from the uranium containing supernatant solution, and is dried and calcined to the oxides. The thorium and rare earth oxides are then dissolved in nitric acid and the solution is contacted with tribntyl phosphate whereby an organic extract phase containing the cerium and thorium values is obtained, together with an aqueous raffinate containing the other rare earth values. The organic phase is then separated from the aqueous raffinate and the cerium and thorium are back extracted with an aqueous medium.

  4. Sea sand for reactive barriers

    International Nuclear Information System (INIS)

    Garcia R, G.; Ordonez R, E.; Ordonez R, En.

    2002-01-01

    Some phosphates have the property to suck in radioactive metals in solution, what it is taken in advance to make reactive barriers which are placed in the nuclear waste repositories. In an effort for contributing to the study of this type of materials, it has been obtained the zirconium silicate (ZrSiO 4 ) and the alpha zirconium hydrogen phosphate (Zr(HPO 4 ) 2H 2 O) starting from sea sand in an easy and economic way. (Author)

  5. Effects of oil sands sediments on fish

    International Nuclear Information System (INIS)

    Parrott, J.; Colavecchia, M.; Hewitt, L.; Sherry, J.; Headley, J.; Turcotte, D.; Liber, K.

    2010-01-01

    This paper described a collaborative project organized by Natural Resources Canada (NRCan) Panel of Energy Research and Development (PERD) with researchers from Environment Canada and the University of Saskatchewan. The 4-year study was conducted to assess the toxicity of oil sands sediments and river waters, and reclamation ponds and sediments on laboratory-raised fish. Three sediments from rivers were evaluated for their potential to cause adverse impacts on fathead minnow eggs and larvae for a period of 18 days. The study monitored hatching, larval survival, development, and growth. Naphthenic acids (NA), polycyclic aromatic hydrocarbons (PAHs) and metals were measured in the sediments to determine if the compounds can be correlated with observed toxicity. The study will also assess walleye eggs exposed to sediments, and in situ fish exposures. Toxicity identification and evaluation (TIE) studies will be conducted to isolate the fractions that may affect fish development and growth.

  6. 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...

  7. Sources and processes affecting the distribution of dissolved Nd isotopes and concentrations in the West Pacific

    Science.gov (United States)

    Behrens, Melanie K.; Pahnke, Katharina; Schnetger, Bernhard; Brumsack, Hans-Jürgen

    2018-02-01

    In the Atlantic, where deep circulation is vigorous, the dissolved neodymium (Nd) isotopic composition (expressed as ɛNd) is largely controlled by water mass mixing. In contrast, the factors influencing the ɛNd distribution in the Pacific, marked by sluggish circulation, is not clear yet. Indication for regional overprints in the Pacific is given based on its bordering volcanic islands. Our study aims to clarify the impact and relative importance of different Nd sources (rivers, volcanic islands), vertical (bio)geochemical processes and lateral water mass transport in controlling dissolved ɛNd and Nd concentration ([Nd]) distributions in the West Pacific between South Korea and Fiji. We find indication for unradiogenic continental input from South Korean and Chinese rivers to the East China Sea. In the tropical West Pacific, volcanic islands supply Nd to surface and subsurface waters and modify their ɛNd to radiogenic values of up to +0.7. These radiogenic signatures allow detailed tracing of currents flowing to the east and differentiation from westward currents with open ocean Pacific ɛNd composition in the complex tropical Pacific zonal current system. Modified radiogenic ɛNd of West Pacific intermediate to bottom waters upstream or within our section also indicates non-conservative behavior of ɛNd due to boundary exchange at volcanic island margins, submarine ridges, and with hydrothermal particles. Only subsurface to deep waters (3000 m) in the open Northwest Pacific show conservative behavior of ɛNd. In contrast, we find a striking correlation of extremely low (down to 2.77 pmol/kg Nd) and laterally constant [Nd] with the high-salinity North and South Pacific Tropical Water, indicating lateral transport of preformed [Nd] from the North and South Pacific subtropical gyres into the study area. This observation also explains the previously observed low subsurface [Nd] in the tropical West Pacific. Similarly, Western South Pacific Central Water, Antarctic

  8. Modeling fine-scale geological heterogeneity-examples of sand lenses in tills

    DEFF Research Database (Denmark)

    Kessler, Timo Christian; Comunian, Alessandro; Oriani, Fabio

    2013-01-01

    that hamper subsequent simulation. Transition probability (TP) and multiple-point statistics (MPS) were employed to simulate sand lens heterogeneity. We used one cross-section to parameterize the spatial correlation and a second, parallel section as a reference: it allowed testing the quality......Sand lenses at various spatial scales are recognized to add heterogeneity to glacial sediments. They have high hydraulic conductivities relative to the surrounding till matrix and may affect the advective transport of water and contaminants in clayey till settings. Sand lenses were investigated...... on till outcrops producing binary images of geological cross-sections capturing the size, shape and distribution of individual features. Sand lenses occur as elongated, anisotropic geobodies that vary in size and extent. Besides, sand lenses show strong non-stationary patterns on section images...

  9. Gases Emission From Surface Layers of Sand Moulds and Cores Stored Under the Humid Air Conditions

    Directory of Open Access Journals (Sweden)

    Kaźnica N.

    2017-12-01

    Full Text Available A large number of defects of castings made in sand moulds is caused by gases. There are several sources of gases: gases emitted from moulds, cores or protective coatings during pouring and casting solidification; water in moulding sands; moisture adsorbed from surroundings due to atmospheric conditions changes. In investigations of gas volumetric emissions of moulding sands amounts of gases emitted from moulding sand were determined - up to now - in dependence of the applied binders, sand grains, protective coatings or alloys used for moulds pouring. The results of investigating gas volumetric emissions of thin-walled sand cores poured with liquid metal are presented in the hereby paper. They correspond to the surface layer in the mould work part, which is decisive for the surface quality of the obtained castings. In addition, cores were stored under conditions of a high air humidity, where due to large differences in humidity, the moisture - from surroundings - was adsorbed into the surface layer of the sand mould. Due to that, it was possible to asses the influence of the adsorbed moisture on the gas volumetric emission from moulds and cores surface layers by means of the new method of investigating the gas emission kinetics from thin moulding sand layers heated by liquid metal. The results of investigations of kinetics of the gas emission from moulding sands with furan and alkyd resins as well as with hydrated sodium silicate (water glass are presented. Kinetics of gases emissions from these kinds of moulding sands poured with Al-Si alloy were compared.

  10. Enhanced mobility of non aqueous phase liquid (NAPL) during drying of wet sand

    Science.gov (United States)

    Govindarajan, Dhivakar; Deshpande, Abhijit P.; Raghunathan, Ravikrishna

    2018-02-01

    Enhanced upward mobility of a non aqueous phase liquid (NAPL) present in wet sand during natural drying, and in the absence of any external pressure gradients, is reported for the first time. This mobility was significantly higher than that expected from capillary rise. Experiments were performed in a glass column with a small layer of NAPL-saturated sand trapped between two layers of water-saturated sand. Drying of the wet sand was induced by flow of air across the top surface of the wet sand. The upward movement of the NAPL, in the direction of water transport, commenced when the drying effect reached the location of the NAPL and continued as long as there was significant water evaporation in the vicinity of NAPL, indicating a clear correlation between the NAPL rise and water evaporation. The magnitude and the rate of NAPL rise was measured at different water evaporation rates, different initial locations of the NAPL, different grain size of the sand and the type of NAPL (on the basis of different NAPL-glass contact angle, viscosity and density). A positive correlation was observed between average rate of NAPL rise and the water evaporation while a negative correlation was obtained between the average NAPL rise rate and the NAPL properties of contact angle, viscosity and density. There was no significant correlation of average NAPL rise rate with variation of sand grain size between 0.1 to 0.5 mm. Based on these observations and on previous studies reported in the literature, two possible mechanisms are hypothesized -a) the effect of the spreading coefficient resulting in the wetting of NAPL on the water films created and b) a moving water film due to evaporation that "drags" the NAPL upwards. The NAPL rise reported in this paper has implications in fate and transport of chemicals in NAPL contaminated porous media such as soils and exposed dredged sediment material, which are subjected to varying water saturation levels due to drying and rewetting.

  11. 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

  12. Sorption and desorption of arsenic to ferrihydrite in a sand filter.

    Science.gov (United States)

    Jessen, Soren; Larsen, Flemming; Koch, Christian Bender; Arvin, Erik

    2005-10-15

    Elevated arsenic concentrations in drinking water occur in many places around the world. Arsenic is deleterious to humans, and consequently, As water treatment techniques are sought. To optimize arsenic removal, sorption and desorption processes were studied at a drinking water treatment plant with aeration and sand filtration of ferrous iron rich groundwater at Elmevej Water Works, Fensmark, Denmark. Filter sand and pore water were sampled along depth profiles in the filters. The sand was coated with a 100-300 microm thick layer of porous Si-Ca-As-contaning iron oxide (As/Fe = 0.17) with locally some manganese oxide. The iron oxide was identified as a Si-stabilized abiotically formed two-line ferrihydrite with a magnetic hyperfine field of 45.8 T at 5 K. The raw water has an As concentration of 25 microg/L, predominantly as As(II). As the water passes through the filters, As(III) is oxidized to As(V) and the total concentrations drop asymptotically to a approximately 15 microg/L equilibrium concentration. Mn is released to the pore water, indicating the existence of reactive manganese oxides within the oxide coating, which probably play a role for the rapid As(III) oxidation. The As removal in the sand filters appears controlled by sorption equilibrium onto the ferrihydrite. By addition of ferrous chloride (3.65 mg of Fe(II)/L) to the water stream between two serially connected filters, a 3 microg/L As concentration is created in the water that infiltrates into the second sand filter. However, as water flow is reestablished through the second filter, As desorbs from the ferrihydrite and increases until the 15 microg/L equilibrium concentration. Sequential chemical extractions and geometrical estimates of the fraction of surface-associated As suggest that up to 40% of the total As can be remobilized in response to changes in the water chemistry in the sand filter.

  13. Nitrate retention in a sand plains stream and the importance of groundwater discharge

    Science.gov (United States)

    Robert S. Stelzer; Damion R. Drover; Susan L. Eggert; Maureen A. Muldoon

    2011-01-01

    We measured net nitrate retention by mass balance in a 700-m upwelling reach of a third-order sand plains stream, Emmons Creek, from January 2007 to November 2008. Surface water and ground-water fluxes of nitrate were determined from continuous records of discharge and from nitrate concentrations based on weekly and biweekly sampling at three surface water stations and...

  14. Studies in Phlebotomine Sand Flies.

    Science.gov (United States)

    1982-06-30

    Reporte de dos casos de [a ology of a sand fly, P/mlebolomu’,s diabolicuw Hall. in forma anergica difusa. Der matol. Rev. Mex. southwestern -Texas...Contribuiin al estudio de los Phmle- CDC, Veterinary Public Health Notes. USDHEW. bwmwnn de Costa Rica (Diptera, Psychodidae). Tesis. CDC. October. pp. 6- 7...janeiron R. j. 195 pp. the Unrited States (D1)pre ra: Psscfirdidae). j. Ortiz, 1. 1965a. Contribuci~in a! estudio tie los flebor- Partrsirtrl. 30:274-275

  15. 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.

  16. Coastal Foredune Evolution, Part 1: Environmental Factors and Forcing Processes Affecting Morphological Evolution

    Science.gov (United States)

    2017-02-01

    morphological features on the dune , such as its toe or crest (e.g., Sallenger 2000), bringing waves into contact with different portions of the dune ...responses (Sallenger 2000). When total storm water levels are above the dune toe but lower than the dune crest, wave bores and swash collide with the dune ...Depending on the magnitude of sequential wave runups, this slump block is then eroded away or remains at the toe of the dune , effectively increasing the

  17. Physical Processes Affecting the Distribution of Diydymosphenia Geminata Biomass Bloom in Rapid Creek, South Dakota

    Science.gov (United States)

    Abessa, M. B.; Sundareshwar, P. V.; Updhayay, S.

    2010-12-01

    Didymosphenia geminata is a freshwater diatom that has invaded and colonized many of the world’s oligotrophic streams and rivers, including Rapid Creek in Western South Dakota - a perennial oligotrophic stream that emerges from the Black Hills and is fed by cold water release from the Pactola Reservoir. Since 2002, D. geminata blooms have been observed in certain stretches of the Rapid Creek. These massive blooms are localized to certain segments of the Creek where the flow is mainly slow, stable and shallow dominated by boulder type bed material and submerged large woody debris. Water chemistry data from this Creek showed the variability of major nutrients such as phosphate, nitrates/nitrites and ammonium are insignificant across our study sites while the nature of the stream flow is quite irregular. We measured flow rates, depth, temperature, stream bed characteristics, water chemistry, and D. geminata biomass in regions with and without blooms. The presentation will discuss how changes in physical parameters along the various reaches of the Creek impact the biomass distribution of this invasive alga.

  18. Characteristics and Dynamics of a Large Sub-Tidal Sand Wave Field—Habitat for Pacific Sand Lance (Ammodytes personatus, Salish Sea, Washington, USA

    Directory of Open Access Journals (Sweden)

    H. Gary Greene

    2017-10-01

    Full Text Available Deep-water sand wave fields in the San Juan Archipelago of the Salish Sea and Pacific Northwest Washington, USA, have been found to harbor Pacific sand lance (PSL, Ammodytes personatus, a critical forage fish of the region. Little is known of the dynamics of these sand waves and the stability of the PSL sub-tidal habitats. Therefore, we have undertaken an initial investigation to determine the dynamic conditions of a well-known PSL habitat in the San Juan Channel within the Archipelago using bottom sediment sampling, an acoustical doppler current profiling (ADCP system, and multi-beam echo sounder (MBES bathymetry. Our study indicates that the San Juan Channel sand wave field maintained its shape and bedforms geometry throughout the years it has been studied. Based on bed phase diagrams for channelized bedforms, the sand waves appear to be in a dynamic equilibrium condition. Sea level rise may change the current regime within the Archipelago and may alter some of the deep-water or sub-tidal PSL habitats mapped there. Our findings have global significance in that these dynamic bedforms that harbor PSL and sand-eels elsewhere along the west coast of North America and in the North Sea may also be in a marginally dynamic equilibrium condition and may be prone to alteration by sea level rise, indicating an urgency in locating and investigating these habitats in order to sustain the forage fish.

  19. Clean energy and hydrogen for oil sands development with CANDU SCWR nuclear reactors and Cu-Cl cycles

    International Nuclear Information System (INIS)

    Wang, Z.L.; Naterer, G.F.; Gabriel, K.S.

    2010-01-01

    In this paper, the unique capabilities and advantages of SCWR technology for cleaner oil sands development are discussed from two perspectives: lower temperature steam generation by supercritical water for steam assisted gravity drainage (SAGD), and hydrogen production for oil sands upgrading by coupling SCWR with the thermochemical copper-chlorine (Cu-Cl) cycle. The heat requirements for bitumen extraction from the oil sands and the hydrogen requirements for bitumen upgrading are evaluated. A conceptual layout of SCWR coupled with oil sands development is presented. The reduction of CO 2 emissions due to the use of SCWR and thermo chemical hydrogen production cycle is also analyzed. (author)

  20. Properties of palm oil fuel ash cement sand brick containing pulverized cockle shell as partial sand replacement

    Science.gov (United States)

    Mat Aris, S.; Muthusamy, K.; Uzer, A.; Ahmad, S. Wan

    2018-04-01

    Environmental pollution caused by the disposal of solid wastes generated from both palm oil industry and cockle shell trade has motivated researches to explore the potential of these wastes. Integrating these wastes in production of construction material is one of the ways to reduce amount of waste thrown at dumping area. Thus, the present investigation investigates the performance of palm oil fuel ash (POFA) cement sand brick containing pulverized cockle shell as partial fine aggregate replacement. All mixes used contain 20% of POFA as partial cement replacement. Total of six mixes were prepared by adding a range of pulverized cockle shell that is 0%, 10%, 20%, 30%, 40% and 50% as partial sand replacement. The mixes were prepared in form of brick. All the water cured samples were tested for compressive strength and flexural strength until 28 days. Findings show that brick produced using 20% pulverized cockle shell exhibit the highest compressive strength and flexural strength also the lowest water absorption value.

  1. 33 CFR 165.1406 - Safety Zone: Pacific Missile Range Facility (PMRF), Barking Sands, Island of Kauai, Hawaii.

    Science.gov (United States)

    2010-07-01

    ... Range Facility (PMRF), Barking Sands, Island of Kauai, Hawaii. 165.1406 Section 165.1406 Navigation and...), Barking Sands, Island of Kauai, Hawaii. (a) Location. The following area is established as a safety zone during launch operations at PMRF, Kauai, Hawaii: The waters bounded by the following coordinates: (22°01...

  2. Galveston Island, Texas, Sand Management Strategies

    Science.gov (United States)

    2016-07-01

    billion m3 of beach quality sand . However, Texas projects to date have not utilized these sources because of transportation costs. The lack of nearby...estimate that the San Luis Pass flood shoal contains approximately 11.8 million yd3 of beach quality sand . However, it is expected that if permits...a source of beach- quality sand . 2. Sand could be intercepted before it reaches the present dry beach. ERDC/CHL TR-16-13 55 3. The volume of

  3. Crushed rock sand – An economical and ecological alternative to natural sand to optimize concrete mix

    Directory of Open Access Journals (Sweden)

    Sanjay Mundra

    2016-09-01

    Full Text Available The study investigates the use of crushed rock sand as viable alternative to Natural River sand that is being conventionally used as fine aggregate in cement concrete. Various mix designs were developed for different grades of concrete based on IS, ACI and British codes using Natural River sand and crushed rock sand. In each case, the cube compressive strength test, and beam flexure tests were conducted. The results of the study show that, the strength properties of concrete using crushed rock sand are nearly similar to the conventional concrete. The study has shown that crushed stone sand can be used as economic and readily available alternative to river sand and can therefore help to arrest the detrimental effects on the environment caused due to excessive mining of river sand.

  4. Alberta Oil Sands Equity annual report, 1992-93. Partnership and progress in Alberta's oil sands development

    International Nuclear Information System (INIS)

    1993-01-01

    Alberta Oil Sands Equity (AOSE) manages the Alberta government's equity investments in oil sands and heavy oil projects. AOSE is a 16.74% participant in the Syncrude Project, a 10% participant in the OSLO (Other Six Leases Operation) Commercial Project and the OSLO New Ventures project, and a 24.17% participant in the Lloydminster Bi-Provincial Upgrader. Syncrude produces ca 12% of Canadian crude oil requirements, and AOSE's share yielded $44 million profit for 1992/93, slightly higher than the the $43.3 million the previous year. The OSLO Commercial Project is a proposed commercial oil sands plant with a mine site and extraction plant to be located north of Fort McMurray, and an upgrading facility to be situated north of Edmonton. Work on this project was suspended in early 1992. The OSLO New Ventures project will handle the exploration and development of the remaining five oil sands leases plus the southern portion of Lease 31. As of March 31, 1993, the project owners were considering a commercial demonstration project utilizing dredging and cold-water extraction processes. Two of the owners are unable to provide funding and discussions are under way to resolve the matter and move the program forward. The Lloydminster Bi-Provincial Upgrader opened Noveber 20, 1992, and production has reached 41,000 bbl/d, or 89% of design capacity. The upgrader will increase the value of heavy crude oil and thereby increase its demand. 5 figs., 3 tabs

  5. Application and appreciation of chemical sand fixing agent-poly (aspartic acid) and its composites

    Energy Technology Data Exchange (ETDEWEB)

    Yang Jun; Cao Hui; Wang Fang [Beijing Key Laboratory of Bioprocess, Beijing University of Chemical Technology, Beijing 100029 (China); Tan Tianwei [Beijing Key Laboratory of Bioprocess, Beijing University of Chemical Technology, Beijing 100029 (China)], E-mail: twtan@mail.buct.edu.cn

    2007-12-15

    The sand fixing agent-poly (aspartic acid) (PASP) and its composites were applied in the field by two forms (spraying around by PASP solution and PASP powder directly). It was found that the sand fixing effect in powder form was not as good as in solution form, but it was more practical in dry region. It needed 9, 6 and 7 days for PASP, xanthan gum-PASP (X2) and ethyl cellulose-PASP (E3) to attain the maximal mechanical strength after they were applied, respectively. The sand fixing effect decreased when the material was subjected to repeated hydration-dehydration cycles and the material had no negative influence on plant growth. The PASP and its composites had water-retaining ability and could reduce the water evaporation. - The sand fixing agent was applied in powder form and it had no negative influence on plant growth.

  6. Comparison of physical and mechanical properties of river sand concrete with quarry dust concrete

    Science.gov (United States)

    Opara, Hyginus E.; Eziefula, Uchechi G.; Eziefula, Bennett I.

    2018-03-01

    This study compared the physical and mechanical properties of river sand concrete with quarry dust concrete. The constituent materials were batched by weight. The water-cement ratio and mix ratio selected for the experimental investigation were 0.55 and 1:2:4, respectively. The specimens were cured for 7, 14, 21 and 28 days. Slump, density and compressive strength tests were carried out. The results showed that river sand concrete had greater density and compressive strength than quarry dust concrete for all curing ages. At 28 days of curing, river sand concrete exceeded the target compressive strength by 36%, whereas quarry dust concrete was less than the target compressive strength by 12%. Both river sand concrete and quarry dust concrete for the selected water/cement ratio and mix ratio are suitable for non-structural applications and lightly-loaded members where high strength is not a prerequisite.

  7. PHYSICAL PROPERTIES OF KAOLIN/SAND SLURRY USED DURING SUBMERSIBLE MIXER PUMP TESTS AT TNX

    International Nuclear Information System (INIS)

    HANSEN, ERICH

    2005-01-01

    The purpose of this task is to characterize the physical properties of the kaolin/sand slurries used during the testing of a new submersible mixer pump (SMP) which had undergone performance testing at the TNX Waste Tank mockup facility from July 2004 through May 2005. During this time period, four identical SMPs were subjected to various water tests and four different tests using different batches of kaolin/sand slurries. The physical properties of the kaolin/sand slurries were measured for three of the four tests. In these tests, three different sample locations were used to pull samples, the SMP cooling water exit (CWE), the SMP fluid flow field (FFF), and SMP effective cleaning radius (ECR). The physical properties measured, though not for each sample, included rheology, weight percent total solids (wt% TS), density, kaolin/sand slurry particle size distribution (PSD), weight percent and particles size distribution of material greater than 45 microns

  8. From ooze to sedimentary rock, the first diagenetic processes affecting the chalk of eastern Denmark

    DEFF Research Database (Denmark)

    Moreau, Julien; Boussaha, Myriam; Nielsen, Lars

    processes operating in the chalk sediments at widely different scales into a single diagenetic model: At Stevns the chalk is affected by an extensive polygonal fault system which is expressed in onshore and offshore seismic profiles. Smaller scale contractional features like deformation bands (hairline...... strongly affect reservoir properties of the chalk both by establishing compartments and vertical connections. A better understanding of these reservoir modifications will be critical for improving the predictive capability of models describing the behaviour of drinking water and hydrocarbons hosted...

  9. Persistent organic pollutants in Mediterranean seawater and processes affecting their accumulation in plankton.

    Science.gov (United States)

    Berrojalbiz, Naiara; Dachs, Jordi; Del Vento, Sabino; Ojeda, María José; Valle, María Carmen; Castro-Jiménez, Javier; Mariani, Giulio; Wollgast, Jan; Hanke, Georg

    2011-05-15

    The Mediterranean and Black Seas are unique marine environments subject to important anthropogenic pressures due to riverine and atmospheric inputs of organic pollutants. Here, we report the results obtained during two east-west sampling cruises in June 2006 and May 2007 from Barcelona to Istanbul and Alexandria, respectively, where water and plankton samples were collected simultaneously. Both matrixes were analyzed for hexaclorochyclohexanes (HCHs), hexachlorobenzene (HCB), and 41 polychlorinated biphenyl (PCB) congeners. The comparison of the measured HCB and HCHs concentrations with previously reported dissolved phase concentrations suggests a temporal decline in their concentrations since the 1990s. On the contrary, PCB seawater concentrations did not exhibit such a decline, but show a significant spatial variability in dissolved concentrations with lower levels in the open Western and South Eastern Mediterranean, and higher concentrations in the Black, Marmara, and Aegean Seas and Sicilian Strait. PCB and OCPs (organochlorine pesticides) concentrations in plankton were higher at lower plankton biomass, but the intensity of this trend depended on the compound hydrophobicity (K(OW)). For the more persistent PCBs and HCB, the observed dependence of POP concentrations in plankton versus biomass can be explained by interactions between air-water exchange, particle settling, and/or bioaccumulation processes, whereas degradation processes occurring in the photic zone drive the trends shown by the more labile HCHs. The results presented here provide clear evidence of the important physical and biogeochemical controls on POP occurrence in the marine environment.

  10. Evolution of the gas atmosphere during filing the sand moulds with iron alloys

    Directory of Open Access Journals (Sweden)

    J. Mocek

    2009-10-01

    Full Text Available Evolution of atmosphere of the mould cavity when pouring the cast iron has been analyzed. It was find that in dry sand mold the cavity is filled by air throughout the casting time. In green sand the air is removed by the water vapor the hydrogen or carbon oxides formed in contact with the liquid metal. The theoretical results have been confirmed experimentally.

  11. IMPACT OF SAND DREDGING AND SILT EXTRACTION ACTIVITY ON RIVER AND ITS CHARACTERISTICS : A REVIEW

    OpenAIRE

    Vishal S. Gholap

    2016-01-01

    The present research work highlights the influences of sand dredging and extensive silt quarrying activity on rivers. The sand dredging activity and its impact on the river processes and other river environment have discussed in the present review paper. It has seen that most of the rivers and their processes are highly degraded and altered due to these activities. In India and almost in the regions of Maharashtra, the ground water is decreasing and such activities also invited the problems ...

  12. Sand dune tracking from satellite laser altimetry

    Science.gov (United States)

    Dabboor, Mohammed

    Substantial problems arise from sand movement in arid and semi-arid countries. Sand poses a threat to infrastructure, agricultural and urban areas. These issues are caused by the encroachment of sand on roads and railway tracks, farmland, towns and villages, and airports, to name a few. Sand movement highly depends on geomorphology including vegetation cover, shape and height of the terrain, and grain size of the sand. However, wind direction and speed are the most important factors that affect efficient sand movement. The direction of the movement depends on the main direction of the wind, but it has been shown that a minimum wind speed is required, e.g. wind gusts, to initiate sand transport. This fact prevents a simple calculation of sand transport from conventional wind data as wind records rarely contain sub-minute intervals masking out any wind gusts. An alternative of predicting sand transport is the direct observation of sand advance by in situ measurements or via satellite. Until recently, satellite imagery was the only means to compare dune shape and position for predicting dune migration over several years. In 2003, the NASA laser altimetry mission ICESat became operational and monitors elevations over all surface types including sand dunes with an accuracy of about 10-20 cm. In this study, ICESat observations from repeat tracks (tracks overlapping eachother within 50 m) are used to derive sand dune advance and direction. The method employs a correlation of the elevation profiles over several dunes and was sucessfully validated with synthetic data. The accuracy of this method is 5 meters of dune advance. One of the most active areas exhibiting sand and dune movement is the area of the Arabian Peninsula. Approximately one-third of the Arabian Peninsula is covered by sand dunes. Different wind regimes (Shamal, Kaus) cause sand dune movement in the selected study area in the eastern part of the Arabian Peninsula between 20-25 degrees North and 45-55 degrees

  13. Sandscape - engaging people in Met Office science through sand sculpture

    Science.gov (United States)

    Liggins, Felicity; Dowell, Ellen; Wardley, Jamie; Jamieson, Claire

    2017-04-01

    In 2015, the Met Office's award-winning outreach programme, designed to inspire the next generation of scientists and engineers, delivered one of its most ambitious and creative activities to date. It explored how scientists and artists can come together to create an engaging experience for young people and families. This activity was called Sandscape. Sandscape is an interactive sand sculpture workshop exploring how weather and climate affect our health. Budding sand sculptors are shown how to fashion elaborate structures from sand and water - creating a landscape with bridges, skyscrapers, forests and factories. As they work, participants are encouraged by the scientists delivering the activity to reflect on what makes a healthy city, considering how the natural and built environments influence air quality and circulation and how this impacts our health. Topics discussed include urban heat islands, air pollution and dispersion modelling, pollen forecasting and predicting the wind-borne spread of animal diseases. Each hour long workshop culminates in a dramatic demonstration that uses dry ice to represent clean air circulating from mountains, along rivers and into cities. Here we present an overview of Sandscape, identify the strengths and challenges of such a collaborative, innovative and playful approach to public engagement and share the results of our evaluation. Sandscape was originally supported by the Met Office and the Wellcome Trust, and produced by Einstein's Garden in collaboration with the Met Office, scientists from the University of Exeter and sand sculptors from Sand in Your Eye. It was first presented in Einstein's Garden at Green Man festival 2015, an independent music and arts festival held annually in Wales, and has since been invited to run at the 2015 Bournemouth Arts By the Sea Festival and Teignmouth's TRAIL Sculpture Festival in the summer of 2016.

  14. Sediment transport and mixing depth on a coral reef sand apron

    Science.gov (United States)

    Vila-Concejo, Ana; Harris, Daniel L.; Power, Hannah E.; Shannon, Amelia M.; Webster, Jody M.

    2014-10-01

    This paper investigates the mechanics of sediment transport on a subtidal sand apron located on a coral reef environment. In this environment 100% of the sediment is carbonate bioclasts generated in situ. The sand apron is located on the back reef and only affected by waves during high tides. It is commonly accepted in the literature that sand aprons are features that prograde lagoonwards and that most of the progradation occurs during high-energy events. Measurements of water depths, waves, currents and near bed suspended sediment concentrations (all at 10 Hz) on the sand apron were undertaken over a nine day intensive field campaign over both spring and neap tides; waves and tides were also measured in the lagoon. The topography and bathymetry of the sand apron were measured and mixing depth was obtained on three transects using depth of disturbance rods. We found that sediment transport on sand aprons is not solely restricted to high-energy events but occurs on a daily basis during spring tides. The main factor controlling the sediment transport was the water depth above the bed, with depths of 2-2.3 m allowing waves to promote the most sediment transport. This corresponds to a depth over the reef crest of 1.6-1.9 m. The second most important control was waves; transport was observed when Hs on the apron was 0.1 m or greater. In contrast, current magnitude was not a controlling mechanism for sediment entrainment but did affect sediment transport. The morphology of the sand apron was shown to affect the direction of currents with the currents also expected to influence the morphology of the sand apron. The currents measured during this field campaign were aligned with a shallow channel in the sand apron. Mixing depths were small (< 2.5 cm) yet they were larger than the values predicted by empirical formulae for gentle siliciclastic ocean beaches.

  15. Fuel options for oil sands

    International Nuclear Information System (INIS)

    Wise, T.

    2005-01-01

    This presentation examined fuel options in relation to oil sands production. Options include steam and hydrogen (H 2 ) for upgrading; natural gas by pipeline; bitumen; petroleum coke; and coal. Various cost drivers were also considered for each of the fuel options. It was noted that natural gas has high energy value but the capital cost is low, and that coke's energy value is very low but the capital cost is high. A chart forecasting energy prices was presented. The disposition of Western Canada's northern gas situation was presented. Issues concerning rail transportation for coal were considered. Environmental concerns were also examined. A chart of typical gas requirements for 75,000 B/D oil sands projects was presented. Issues concerning steam generation with gas and mining cogeneration with gas fuel and steam turbines were discussed, as well as cogeneration and H 2 with gas fuels and steam turbines. Various technology and fuel utility options were examined, along with details of equipment and processes. Boiler technologies were reviewed by type as well as fuel and steam quality and pressure. Charts of cogeneration with gas turbine and circulation fluid bed boilers were presented. Gasification processes were reviewed and a supply cost basis was examined. Cost drivers were ranked according to energy, operating considerations and capital investment. Results indicated that fuel costs were significant for gas and coal. Capital costs and capital recovery charge was most significant with coal and gasification technology. Without capital recovery, cash costs favour the use of bitumen and coke. Gasification would need lower capital and lower capital recovery to compete with direct burning. It was concluded that direct burning of bitumen can compete with natural gas. With price volatility anticipated, dual fuel capability for bitumen and gas has merit. Petroleum coke can be produced or retrieved from stockpiles. Utility supply costs of direct burning of coke is

  16. Log analysis in the shallow oil sands of the San Joaquin Valley, California

    International Nuclear Information System (INIS)

    Vohs, J.B.

    1976-01-01

    Many fields in the San Joaquin Valley of California produce oil from a depth of 2,500 ft or less. During the period of primary production in these fields, evaluation of potential pay intervals from logs was restricted to examination of ES logs and correlation. With the introduction of secondary and tertiary recovery techniques the need for more and better answers, more quickly available, became apparent. However, several log-analysis problems had to be resolved. Formation evaluation using well logs was complicated by the shaliness of the sand intervals, the low and variable salinity of the formation waters, and the presence of low-pressure-gas (depleted) zones in many of the shallow sands. Solutions to these problems have required more modern logging programs and interpretation techniques. Logs available for the evaluation of these sands are the dual induction-laterolog, the compensated formation density log, the compensated neutron log, and the microlaterolog or proximity log. With this suite of logs it is possible to determine the shale content, porosity, saturation in the flushed zone, and water saturation of the sand, and to locate the low-pressure-gas sands and depleted zones. In cases where freshwater and oil are interlayered, it is possible to tell which sands contain oil and which contain only water. Because a quick interpretation is required, wellsite techniques are called for. These will be described

  17. Effect of Gamma Irradiation on Polymer Modified White Sand Cement Mortar Composites

    International Nuclear Information System (INIS)

    Khattab, M.M.

    2012-01-01

    This study focuses on the substitution effect of standard sand of conventional cement mortar made from ordinary Portland cement (OPC) and standard sand (SS) OPC/SS 1:3; by different ratios of white sand (WS) powder to prepare three types of white sand cement mortar designated as 1OPC:2SS:1WS, 1OPC:1SS:2WS and 1OPC:0SS:3WS. The prepared samples were first cured under tap water for different time intervals namely 3, 7, 28 and 90 days. The effect of addition of 10% styrene-acrylic ester (SAE) as well as the effect of different doses of gamma rays (10, 20, 30 and 50 kGy) on the physicomechanical properties of polymer modified white sand cement mortar specimens also discussed. Compression strength test, total porosity and water absorption percentages were measured according to standard specifications. The obtained data indicated that, the cement mortar samples containing different ratios of white sand have lower values of compressive strength as compared to the conventional cement mortar while, the percentages of total porosity and water absorption increased. On the other hand, the polymer modified mortar specimens showed a noticeably enhancement in the physico-mechanical properties under the effect of gamma-radiation than those of untreated samples. These results were confirmed by scanning electron microscopy (SEM), and thermogravimetric analysis (TGA) studies

  18. 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.

  19. Nanoscale Chemical Processes Affecting Storage Capacities and Seals during Geologic CO2 Sequestration.

    Science.gov (United States)

    Jun, Young-Shin; Zhang, Lijie; Min, Yujia; Li, Qingyun

    2017-07-18

    Geologic CO 2 sequestration (GCS) is a promising strategy to mitigate anthropogenic CO 2 emission to the atmosphere. Suitable geologic storage sites should have a porous reservoir rock zone where injected CO 2 can displace brine and be stored in pores, and an impermeable zone on top of reservoir rocks to hinder upward movement of buoyant CO 2 . The injection wells (steel casings encased in concrete) pass through these geologic zones and lead CO 2 to the desired zones. In subsurface environments, CO 2 is reactive as both a supercritical (sc) phase and aqueous (aq) species. Its nanoscale chemical reactions with geomedia and wellbores are closely related to the safety and efficiency of CO 2 storage. For example, the injection pressure is determined by the wettability and permeability of geomedia, which can be sensitive to nanoscale mineral-fluid interactions; the sealing safety of the injection sites is affected by the opening and closing of fractures in caprocks and the alteration of wellbore integrity caused by nanoscale chemical reactions; and the time scale for CO 2 mineralization is also largely dependent on the chemical reactivities of the reservoir rocks. Therefore, nanoscale chemical processes can influence the hydrogeological and mechanical properties of geomedia, such as their wettability, permeability, mechanical strength, and fracturing. This Account reviews our group's work on nanoscale chemical reactions and their qualitative impacts on seal integrity and storage capacity at GCS sites from four points of view. First, studies on dissolution of feldspar, an important reservoir rock constituent, and subsequent secondary mineral precipitation are discussed, focusing on the effects of feldspar crystallography, cations, and sulfate anions. Second, interfacial reactions between caprock and brine are introduced using model clay minerals, with focuses on the effects of water chemistries (salinity and organic ligands) and water content on mineral dissolution and

  20. Understanding Colombian Amazonian white sand forests

    NARCIS (Netherlands)

    Peñuela-Mora, M.C.

    2014-01-01

    Although progress has been made in studies on white sand forests in the Amazon, there is still a considerable gap in our knowledge of the unique species composition of white sand forests and their structure and dynamics, especially in Western Amazon. This thesis aims to fill this gap by addressing

  1. Characterization of sand lenses embedded in tills

    DEFF Research Database (Denmark)

    Kessler, Timo Christian; Klint, K.E.S.; Nilsson, B.

    2012-01-01

    Tills dominate large parts of the superficial sediments on the Northern hemisphere. These glacial diamictons are extremely heterogeneous and riddled with fractures and lenses of sand or gravel. The frequency and geometry of sand lenses within tills are strongly linked to glaciodynamic processes...

  2. Japan's involvement in oil sands development

    International Nuclear Information System (INIS)

    Sugiura, T.

    1994-01-01

    According to Japanese national policy, exploration and development by Japanese companies in overseas countries are promoted in order to ensure stable oil supplies. Japan Canada Oil Sands Limited (JACOS), part of the JAPEX group, was established during the 1978 world oil crisis to explore and develop Canadian oil sand resources in accordance with Japan's national policy. The JAPEX group, including JACOS, has invested $123 million in oil sands projects in Alberta. JAPEX's first involvement in oil sands was in the Primrose Project operated by Norcen in the Cold Lake area. Five years of cyclic steam stimulation pilot tests did not produce sufficiently good results to justify further operation. The second involvement was the PCEJ Project, a joint effort by four companies that are participating in a bitumen recovery test project in the Athabasca Deposit. JACOS holds 2,452 km 2 of oil sands leases in Alberta. Tests conducted since 1978 in the PCEJ Project include multiwell steam injection pilot tests, some of which showed promise. JACOS is also participating in steam assisted gravity drainage projects and in federal/provincial research programs. Obstacles identified in developing Alberta oil sands are the lack of a bitumen pipeline to Edmonton and the insufficient length of oil sands leases (currently 10 years), given the difficulties of oil sand development. 10 figs

  3. Seasonal fluctuations of phlebotomines sand fly populations ...

    African Journals Online (AJOL)

    An entomological survey of phlebotomine sand flies was conducted in the Moulay Yacoub province, central Morocco. An anthropic niche (Ouled Aid) and a wild niche (Zliligh) were selected. Sand flies were collected twice a month between April 2011 and March 2012, using sticky traps and CDC light traps. 3675 specimens ...

  4. On shelterbelt design for combating sand invasion.

    NARCIS (Netherlands)

    Mohammed, A.E.; Stigter, C.J.; Adam, H.S.

    1996-01-01

    After a review of the scarce literature on using trees against sand encroachment, a quantitative experiment with a wide shelterbelt to combat sand invasion is reported on. Experimental work was carried out at the northwestern border of the Gezira Scheme (Sudan), an area of severe land degradation

  5. Design of dry sand soil stratified sampler

    Science.gov (United States)

    Li, Erkang; Chen, Wei; Feng, Xiao; Liao, Hongbo; Liang, Xiaodong

    2018-04-01

    This paper presents a design of a stratified sampler for dry sand soil, which can be used for stratified sampling of loose sand under certain conditions. Our group designed the mechanical structure of a portable, single - person, dry sandy soil stratified sampler. We have set up a mathematical model for the sampler. It lays the foundation for further development of design research.

  6. 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

  7. Evaluation of hydrologic processes affecting soil movement in the Hagerman fauna area, Hagerman, Idaho

    Science.gov (United States)

    Young, H.W.

    1984-01-01

    The Hagerman fauna area on the western slope of the Snake River canyon in south-central Idaho is one of the most important locations of upper Pliocene fossils in the world. The fossil beds are distributed vertically through a 500-foot stratigraphic section of the Glenns Ferry Formation. Accelerated soil movement caused by surface-water runoff from irrigated farmlands on the plateau above the canyon and discharge from springs and seeps along the slope of the canyon is eroding the fossil beds. Source of the springs and seeps is a perched aquifer, which is probably recharged by seepage losses from two irrigation canals that head near the canyon rim. Annual canal losses are about 1,900 acre-feet. Annual discharge from springs and seeps is about 420 acre-feet. Corrective measures that could be taken to stabilize the soil movement and preserve the fauna area include: (1) Lining or treating the canals, (2) eliminating the practice of flushing irrigation systems, (3) constructing road berms and cross dips, and (4) establishing an uncultivated strip of land between irrigated farmlands and the canyon rim. (USGS)

  8. Biophysical processes affecting DOM dynamics at the Arno river mouth (Tyrrhenian Sea).

    Science.gov (United States)

    Retelletti Brogi, S; Gonnelli, M; Vestri, S; Santinelli, C

    2015-02-01

    Dissolved organic carbon (DOC) and optical properties (absorption and fluorescence) of chromophoric dissolved organic matter (CDOM) were measured in October 2012, at the Arno river mouth and in a coastal station close to it. The data reported indicates that the Arno river represents an important source of DOC and CDOM to this coastal area, with a total DOC flux of 11.23-12.04 · 10(9)g C · y(-1). Moving from the river to the sea, CDOM absorption and fluorescence decreased, while the spectral slope increased, suggesting a change in the molecular properties of CDOM. Mineralization experiments were carried out in order to investigate the main processes of DOM removal and/or transformation in riverine and coastal water. DOC removal rates were 20 μM · month(-1) in the river and 3 μM · month(-1) in the seawater, while CDOM was released during the first 30 days and removed in the following 40 days. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Similar local and landscape processes affect both a common and a rare newt species.

    Science.gov (United States)

    Denoël, Mathieu; Perez, Amélie; Cornet, Yves; Ficetola, Gentile Francesco

    2013-01-01

    Although rare species are often the focus of conservation measures, more common species may experience similar decline and suffer from the same threatening processes. We tested this hypothesis by examining, through an information-theoretic approach, the importance of ecological processes at multiple scales in the great crested newt Triturus cristatus, regionally endangered and protected in Europe, and the more common smooth newt, Lissotriton vulgaris. Both species were similarly affected by the same processes, i.e. suitability of aquatic and terrestrial components of their habitat at different scales, connectivity among breeding sites, and the presence of introduced fish. T. cristatus depended more on water depth and aquatic vegetation than L. vulgaris. The results show that environmental pressures threaten both common and rare species, and therefore the more widespread species should not be neglected in conservation programs. Because environmental trends are leading to a deterioration of aquatic and terrestrial habitat features required by newt populations, populations of the common species may follow the fate of the rarest species. This could have substantial conservation implications because of the numerical importance of common species in ecosystems and because commonness could be a transient state moving towards rarity. On the other hand, in agreement with the umbrella species concept, targeting conservation efforts on the most demanding species would also protect part of the populations of the most common species.

  10. Developing new markets for oil sands products

    International Nuclear Information System (INIS)

    Crandall, G.

    2004-01-01

    This paper presents a review by Purvin and Gertz of western Canadian crude oil supply. This energy consulting firm provides advise to the energy sector. It suggests that oil sands production will surpass declining conventional production. Oil sands supply includes bitumen, synthetic crude oil (SCO), and diluent. It is forecasted that oil sands will increase from 42 per cent of western supply in 2002 to 78 per cent in 2015. The potential of Alberta's oil sands was discussed along with a recent study of refined products and petrochemicals from bitumen. Upgrading, refining and petrochemical case studies were presented. The author examined if a Canadian oil sands upgrading project with high capital costs can be competitive with competing projects in the United States and internationally. In addition to supply and demand issues, the presentation examined infrastructure capability and market potential in the United States. The economic potential and risks of preferred business cases compared to upgrading to SCO were also evaluated. 15 figs

  11. Numerical simulation of aeolian sand ripples

    International Nuclear Information System (INIS)

    Kang Liqiang; Guo Liejin

    2004-01-01

    With a new horizontal saltation displacement vector, a model is implemented to simulate the initiation and evolution of aeolian sand ripples. In the model, saltation distance considers the effects of surface height and slope. A linear stability analysis is also carried out for formation of sand ripples. The results show that, the model can be able to successfully reproduce sand ripples which can increase in scale by merging of small ripples. The linear stability analysis indicates that sand ripples appear when the relaxation rate parameter is below a threshold value and wind strength parameter is larger than a critical value. The results also verified that the formation of sand ripples is a self-organization process

  12. Investigations of the Influence of the Matrix Recycling on Properties of the Moulding Sand with Geopol 618 Binder

    Directory of Open Access Journals (Sweden)

    J. Kamińska

    2013-01-01

    Full Text Available Self-hardening moulding sands with water-glass hardened by liquid esters are applied in several foundry plants for making moulds for the production of heavy iron and steel castings. The main good point of this process is a low cost of sands. However, on account of a lowsusceptibility of this moulding sand for the matrix reclamation the fraction of sands originated from the reclamation is limited.The investigations presented in this work were aimed at the determination of the addition of the reclaimed material, obtained in the dry mechanical reclamation, on properties of the moulding sand with the Geopol 618 binder, which is water-glass modified by polymers and hardened by esters.

  13. Investigations of the Influence of the Matrix Recycling on Properties of the Moulding Sand with Geopol 618 Binder

    Directory of Open Access Journals (Sweden)

    Kamińska J.

    2013-03-01

    Full Text Available Self-hardening moulding sands with water-glass hardened by liquid esters are applied in several foundry plants for making moulds for the production of heavy iron and steel castings. The main good point of this process is a low cost of sands. However, on account of a low susceptibility of this moulding sand for the matrix reclamation the fraction of sands originated from the reclamation is limited. The investigations presented in this work were aimed at the determination of the addition of the reclaimed material, obtained in the dry mechanical reclamation, on properties of the moulding sand with the Geopol 618 binder, which is water-glass modified by polymers and hardened by esters.

  14. Slow sand filters effectively reduce Phytophthora after a pathogen switch from Fusarium and a simulated pump failure.

    Science.gov (United States)

    Lee, Eric; Oki, Lorence R

    2013-09-15

    Slow sand filtration has been shown to effectively reduce Phytophthora zoospores in irrigation water. This experiment tested the reduction of Phytophthora colony forming units (CFUs) by slow sand filtration systems after switching the pathogen contaminating plant leachate from Fusarium to Phytophthora and the resilience of the system to a short period without water, as might be caused by a pump failure. The slow sand filtration system greatly reduced Phytophthora CFUs and transmission after switching the pathogens. In addition, Phytophthora reduction by the slow sand filter was equally effective before and after the simulated pump failure. Reduction of Fusarium was not seen by the SSFs, before or after the simulated pump failure. The results suggest that slow sand filters are effective at reducing larger organisms, such as Phytophthora zoospores, even after a pump failure or a change in pathogens. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. The importance of sand in the formation of avulsion channels within experimental fans that develop from sediment mixtures of mud and sand

    Science.gov (United States)

    Iscen, N.; Strom, K.

    2017-12-01

    Autogenic channel migration and avulsion has long been recognized as important drivers of alluvial fan dynamics. In the literature, several field studies have documented that the presence and the amount of sand transport through a channel is important for channel incision in alluvial fans and deltas. In our experiments, we present the general autogenic avulsion cycle of experimental alluvial fans with mixtures of cohesive sediment and sand with a range of boundary conditions, and we detail the importance of mobile sand fraction in the development of channels that lead to avulsion. Experimental observations demonstrate that new channels form at topographically low regions within the floodplain providing that sand is transported to these topographic lows due to overbank flow or levee breaching. In addition to the sediment transported from upstream, erosion of a previous deposit and an ongoing backfilling nearby are observed as the possible sources of sand getting into the ghost channels. We explore whether the presence of sand is important for channel development because it increases abrasion of the channel or because it changes the roughness characteristics of the flow. We also examine the affect of sediment and water supply change on the newly described channelization process and link distinctive channel morphologies to different stages of described channel development and the avulsion process.

  16. Modification of Cell Wall Polysaccharides during Drying Process Affects Texture Properties of Apple Chips

    Directory of Open Access Journals (Sweden)

    Min Xiao

    2018-01-01

    Full Text Available The influences of hot air drying (AD, medium- and short-wave infrared drying (IR, instant controlled pressure drop drying (DIC, and vacuum freeze drying (FD on cell wall polysaccharide modification were studied, and the relationship between the modifications and texture properties was analyzed. The results showed that the DIC treated apple chips exhibited the highest crispness (92 and excellent honeycomb-like structure among all the dried samples, whereas the FD dried apple chips had low crispness (10, the minimum hardness (17.4 N, and the highest volume ratio (0.76 and rehydration ratio (7.55. Remarkable decreases in the contents of total galacturonic acid and the amounts of water extractable pectin (WEP were found in all the dried apple chips as compared with the fresh materials. The highest retention of WEP fraction (102.7 mg/g AIR was observed in the FD dried apple chips, which may lead to a low structural rigidity and may be partially responsible for the lower hardness of the FD apple chips. In addition, the crispness of the apple chips obtained by DIC treatment, as well as AD and IR at 90°C, was higher than that of the samples obtained from the other drying processes, which might be due to the severe degradation of pectic polysaccharides, considering the results of the amounts of pectic fractions, the molar mass distribution, and concentrations of the WEP fractions. Overall, the data suggested that the modifications of pectic polysaccharides of apple chips, including the amount of the pectic fractions and their structural characteristics and the extent of degradation, significantly affect the texture of apple chips.

  17. Non-aqueous heavy oil extraction from oil sand

    Energy Technology Data Exchange (ETDEWEB)

    Bohnert, George [National Nuclear Security Administration (United States)

    2011-07-01

    The Kansas City plant operated by Honeywell has a long history of working with DOE NNSA on engineering and manufacturing services supporting national security requirements. The plant has developed a non-aqueous method for heavy oil extraction from oil sands. This method is environmentally friendly as it does not use any external body of water, which would normally be contaminated in the conventional method. It is a 2 phase process consisting of terpene, limonene or alpha pinene, and carbon dioxide. The CO2 and terpene phases are both closed loop systems which minimizes material loss. The limonene and alpha pinene are both naturally derived solvents that come from citrus sources or pine trees respectively. Carbon dioxide is an excellent co-solvent with terpene. There is also a possibility for heat loss recovery during the distillation phase. This process produces clean dry sand. Laboratory tests have concluded that this using non-aqueous liquids process works effectively.

  18. Transport of Phanerochaete chrysosporium and Mucor hiemalis f. irnsingii spores through water-saturated quartz sands; Transport von Phanerochaete chrysosporium- und Mucor hiemalis f. irnsingii-Sporen durch wassergesaettigten Quarzsand

    Energy Technology Data Exchange (ETDEWEB)

    Hoque, E.; Klotz, D.;