WorldWideScience

Sample records for surface horizons leachates

  1. Leachate characterization and assessment of surface and ...

    African Journals Online (AJOL)

    The environment can be impacted negatively by leachates from these dumpsites if not properly managed. This study aimed at assessing the characteristics of municipal solid waste leachate and its contamination potential on surface and groundwater. Leachate, groundwater and surface water samples were collected from ...

  2. Impact assessment of dumpsite leachate on the qualities of surface ...

    African Journals Online (AJOL)

    Impact assessment of dumpsite leachate on the qualities of surface Water and sediment of river eku, ona-ara local government, Oyo State, Nigeria. ... The mean levels of some pollution parameters gave evidence of pollution in River Eku. The results obtained confirmed that the dumpsite leachate was the source of pollutants ...

  3. Ash Leachate Can Reduce Surface Erosion

    Science.gov (United States)

    George J. Holcomb; Philip B. Durgin

    1979-01-01

    In laboratory analyses of the Larabee soil from north-western California, ash leachate flocculated the clay fractions. As a result, the soil quickly settled out of suspension. To test the hypothesis that field plots on disturbed areas treated with ash leachate would be more resistant to erosion than nontreated plots, a study was done in July and August 1978, on two...

  4. Horizons

    Data.gov (United States)

    National Aeronautics and Space Administration — The JPL HORIZONS on-line solar system data and ephemeris computation service provides access to key solar system data and flexible production of highly accurate...

  5. Optimization of fermentative biohydrogen production by response surface methodology using fresh leachate as nutrient supplement.

    Science.gov (United States)

    Liu, Qiang; Zhang, Xiaolei; Zhou, Yinmei; Zhao, Aihua; Chen, Shanping; Qian, Guangren; Xu, Zhi Ping

    2011-09-01

    Fresh compost leachate was used as a nutrients source to facilitate anaerobic fermentative hydrogen production from glucose inoculated with mixed culture. The optimum condition for hydrogen production was predicted by response surface methodology (RSM). The model showed the maximum cumulative hydrogen volume (469.74 mL) and molar hydrogen yield (1.60 mol H2/mol glucose) could be achieved at 6174.93 mg/L glucose and 3383.20 mg COD/L leachate. According to the predicted optimal condition, four tests were carried out to validate the predicted values and evaluate the leachate's effect on co-fermentation with juice wastewater. A maximum cumulative hydrogen volume of 587.05 ± 15.08 mL was obtained in co-fermentation test, and the molar hydrogen yield reached 2.06 ± 0.06 mol H2/mol glucose. The co-fermentation of fresh leachate and glucose/juice wastewater was a combination of acetic acid and butyric acid type-fermentation. The results demonstrated that leachate can serve as a nutrients source for biohydrogen production. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Optimization of Chlorination Process for Mature Leachate Disinfection Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Hamzeh Ali Jamali1

    2014-06-01

    Full Text Available Background: leachate from landfill contains high level of microbial pathogens which is considered as one of the most important threats for the environment. One of the common and simple methods for water and wastewater disinfection is chlorination, but it rarely has been used for leachate disinfection. The objective of this study was evaluating the efficiency of chlorine for leachate disinfection and optimization of the effect of concentration and contact time on the death of total and fecal coliforms, as a microbial contamination index. Methods: In this descriptive-analysis study, microbial indices monitoring in leachates initiated from landfill of Qazvin city were conducted for one year. After pre-tests, the range of chlorine concentration and contact time on the inactivation of microbial indices were determined. Central composite design (CCD and response surface methodology (RSM were applied to optimize chlorine concentration and contact time parameters effect on microbial inactivation. 13 runs of tests were performed on samples. Tests were included BOD, COD, total and fecal coliforms. All analytical experiments were according to the standard methods for the examination of water and wastewater. Results: Results of the study showed that microbial indices had relatively high sensitivity to inactivation by chlorination, which in the chlorine concentration of 2 mg/L and contact time of 9 min, and chlorine concentration of 0.5 mg/L and contact time of 12 min, 100% of total and fecal coliforms inactivated, respectively. The RSM method was used for analysis of bacterial inactivation. Analyses showed that in contact time of 9.4 min and chlorine concentration of 2.99 mg/L, the inactivation efficiency of total and fecal coliforms were 89.16% and 100%, respectively. Conclusions: Chlorine could be used for leachate disinfection. However, in high concentrations of organic matter in leachates, due to production potential of chlorination by-products, health

  7. Protein analysis in dissolved organic matter: What proteins from organic debris, soil leachate and surface water can tell us - a perspective

    Directory of Open Access Journals (Sweden)

    W. X. Schulze

    2005-01-01

    Full Text Available Mass spectrometry based analysis of proteins is widely used to study cellular processes in model organisms. However, it has not yet routinely been applied in environmental research. Based on observations that protein can readily be detected as a component of dissolved organic matter (DOM, this article gives an example about the possible use of protein analysis in ecology and environmental sciences focusing on different terrestrial ecosystems. At this stage, there are two areas of interest: (1 the identification of phylogenetic groups contributing to the environmental protein pool, and (2 identification of the organismic origin of specific enzymes that are important for ecosystem processes. In this paper, mass spectrometric protein analysis was applied to identify proteins from decomposing plant material and DOM of soil leachates and surface water samples derived from different environments. It is concluded, that mass spectrometric protein analysis is capable of distinguishing phylogenetic origin of proteins from litter protein extracts, leachates of different soil horizons, and from various sources of terrestrial surface water. Current limitation is imposed by the limited knowledge of complete genomes of soil organisms. The protein analysis allows to relate protein presence to biogeochemical processes, and to identify the source organisms for specific active enzymes. Further applications, such as in pollution research are conceivable. In summary, the analysis of proteins opens a new area of research between the fields of microbiology and biogeochemistry.

  8. Nitrogen isotope ratios in surface and sub-surface soil horizons

    International Nuclear Information System (INIS)

    Rennie, D.A.; Paul, E.A.

    1975-01-01

    Nitrogen isotope analysis of surface soils and soil-derived nitrate for selected chernozemic and luvisolic soils showed mean delta 15 N values of 11.7 and 11.3, respectively. Isotope enrichment of the total N reached a maximum in the lower B horizon. Sub-soil parent material samples from the one deep profile included in the study indicated a delta 15 N value (NO 3 -N) of 1/3 that of the Ap horizon, at a depth of 180 cm. The delta 15 N of sub-surface soil horizons containing residual fertilizer N were low (-2.2) compared to the surface horizon (9.9). The data reported from this preliminary survey suggest that the natural variations in 15 N abundance between different soils and horizons of the same soil reflect the cumulative effects of soil genesis and soil management. More detailed knowledge and understanding of biological and other processes which control N isotope concentrations in these soils must be obtained before the data reported can be interpreted. (author)

  9. Partial oxidation of landfill leachate in supercritical water: Optimization by response surface methodology

    International Nuclear Information System (INIS)

    Gong, Yanmeng; Wang, Shuzhong; Xu, Haidong; Guo, Yang; Tang, Xingying

    2015-01-01

    Highlights: • Partial oxidation of landfill leachate in supercritical water was investigated. • The process was optimized by Box–Behnken design and response surface methodology. • GY H2 , TRE and CR could exhibit up to 14.32 mmol·gTOC −1 , 82.54% and 94.56%. • Small amounts of oxidant can decrease the generation of tar and char. - Abstract: To achieve the maximum H 2 yield (GY H2 ), TOC removal rate (TRE) and carbon recovery rate (CR), response surface methodology was applied to optimize the process parameters for supercritical water partial oxidation (SWPO) of landfill leachate in a batch reactor. Quadratic polynomial models for GY H2 , CR and TRE were established with Box–Behnken design. GY H2 , CR and TRE reached up to 14.32 mmol·gTOC −1 , 82.54% and 94.56% under optimum conditions, respectively. TRE was invariably above 91.87%. In contrast, TC removal rate (TR) only changed from 8.76% to 32.98%. Furthermore, carbonate and bicarbonate were the most abundant carbonaceous substances in product, whereas CO 2 and H 2 were the most abundant gaseous products. As a product of nitrogen-containing organics, NH 3 has an important effect on gas composition. The carbon balance cannot be reached duo to the formation of tar and char. CR increased with the increase of temperature and oxidation coefficient

  10. Evaluation of electro-oxidation of biologically treated landfill leachate using response surface methodology

    International Nuclear Information System (INIS)

    Zhang Hui; Ran Xiaoni; Wu Xiaogang; Zhang Daobin

    2011-01-01

    Box-Behnken statistical experiment design and response surface methodology were used to investigate electrochemical oxidation of mature landfill leachate pretreated by sequencing batch reactor (SBR). Titanium coated with ruthenium dioxide (RuO 2 ) and iridium dioxide (IrO 2 ) was used as the anode in this study. The variables included current density, inter-electrode gap and reaction time. Response factors were ammonia nitrogen removal efficiency and COD removal efficiency. The response surface methodology models were derived based on the results. The predicted values calculated with the model equations were very close to the experimental values and the models were highly significant. The organic components before and after electrochemical oxidation were determined by GC-MS.

  11. Deepwater Horizon - Estimating surface oil volume distribution in real time

    Science.gov (United States)

    Lehr, B.; Simecek-Beatty, D.; Leifer, I.

    2011-12-01

    Spill responders to the Deepwater Horizon (DWH) oil spill required both the relative spatial distribution and total oil volume of the surface oil. The former was needed on a daily basis to plan and direct local surface recovery and treatment operations. The latter was needed less frequently to provide information for strategic response planning. Unfortunately, the standard spill observation methods were inadequate for an oil spill this size, and new, experimental, methods, were not ready to meet the operational demands of near real-time results. Traditional surface oil estimation tools for large spills include satellite-based sensors to define the spatial extent (but not thickness) of the oil, complemented with trained observers in small aircraft, sometimes supplemented by active or passive remote sensing equipment, to determine surface percent coverage of the 'thick' part of the slick, where the vast majority of the surface oil exists. These tools were also applied to DWH in the early days of the spill but the shear size of the spill prevented synoptic information of the surface slick through the use small aircraft. Also, satellite images of the spill, while large in number, varied considerably in image quality, requiring skilled interpretation of them to identify oil and eliminate false positives. Qualified staff to perform this task were soon in short supply. However, large spills are often events that overcome organizational inertia to the use of new technology. Two prime examples in DWH were the application of hyper-spectral scans from a high-altitude aircraft and more traditional fixed-wing aircraft using multi-spectral scans processed by use of a neural network to determine, respectively, absolute or relative oil thickness. But, with new technology, come new challenges. The hyper-spectral instrument required special viewing conditions that were not present on a daily basis and analysis infrastructure to process the data that was not available at the command

  12. Surface Water Sampling Data for BP Spill/Deepwater Horizon

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Deepwater Horizon oil spill (also referred to as the BP oil spill) began on 20 April 2010 in the Gulf of Mexico on the BP-operated Macondo Prospect. Following...

  13. Partial oxidation of landfill leachate in supercritical water: Optimization by response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Yanmeng; Wang, Shuzhong; Xu, Haidong; Guo, Yang; Tang, Xingying

    2015-09-15

    Highlights: • Partial oxidation of landfill leachate in supercritical water was investigated. • The process was optimized by Box–Behnken design and response surface methodology. • GY{sub H2}, TRE and CR could exhibit up to 14.32 mmol·gTOC{sup −1}, 82.54% and 94.56%. • Small amounts of oxidant can decrease the generation of tar and char. - Abstract: To achieve the maximum H{sub 2} yield (GY{sub H2}), TOC removal rate (TRE) and carbon recovery rate (CR), response surface methodology was applied to optimize the process parameters for supercritical water partial oxidation (SWPO) of landfill leachate in a batch reactor. Quadratic polynomial models for GY{sub H2}, CR and TRE were established with Box–Behnken design. GY{sub H2}, CR and TRE reached up to 14.32 mmol·gTOC{sup −1}, 82.54% and 94.56% under optimum conditions, respectively. TRE was invariably above 91.87%. In contrast, TC removal rate (TR) only changed from 8.76% to 32.98%. Furthermore, carbonate and bicarbonate were the most abundant carbonaceous substances in product, whereas CO{sub 2} and H{sub 2} were the most abundant gaseous products. As a product of nitrogen-containing organics, NH{sub 3} has an important effect on gas composition. The carbon balance cannot be reached duo to the formation of tar and char. CR increased with the increase of temperature and oxidation coefficient.

  14. Isolated, slowly evolving, and dynamical trapping horizons: Geometry and mechanics from surface deformations

    International Nuclear Information System (INIS)

    Booth, Ivan; Fairhurst, Stephen

    2007-01-01

    We study the geometry and dynamics of both isolated and dynamical trapping horizons by considering the allowed variations of their foliating two-surfaces. This provides a common framework that may be used to consider both their possible evolutions and their deformations as well as derive the well-known flux laws. Using this framework, we unify much of what is already known about these objects as well as derive some new results. In particular we characterize and study the ''almost isolated'' trapping horizons known as slowly evolving horizons. It is for these horizons that a dynamical first law holds and this is analogous and closely related to the Hawking-Hartle formula for event horizons

  15. Surface tension of the horizon and Archimedes' principle for gravity

    OpenAIRE

    Shu, Liangsuo; Cui, Kaifeng; Liu, Xiaokang; Liu, Zhichun; Liu, Wei

    2018-01-01

    In this letter, by combining the holographic principle with the graviton Bose-Einstein condensates hypothesis of gravitational backgrounds, we provide a theory of gravity, which provides some kinetic details of how the gravitational coupling between matter and spacetime works. The effective radial potential energy of an object in a gravitational field is found to be the sum of the interfacial energy caused by its micro horizon and the energy required to make room for it by displacing graviton...

  16. Occurrence of antibiotic resistance genes in landfill leachate treatment plant and its effluent-receiving soil and surface water.

    Science.gov (United States)

    Zhang, Xiao-Hua; Xu, Yan-Bin; He, Xiao-Lin; Huang, Lu; Ling, Jia-Yin; Zheng, Li; Du, Qing-Ping

    2016-11-01

    The antibiotic resistance genes (ARGs) from urban waste may spread to the environment with the discharge of leachate. Fifteen types of ARGs, including tetracycline, sulfonamides, AmpC β-lactamase and the class 1 integron gene were detected in the samples from the largest leachate treatment plant (LTP) in Guangzhou and its effluent receiving bodies (soil and surface water). The results showed that ARGs in leachates were in high levels and varied with seasons. The abundance of ARGs in the influent from high to low was in the turn of summer, winter, spring. About 2 to 4 orders of magnitude of ARGs were eliminated by the whole leachate treatment process. The predominant ARGs in the receiving soil were intI1, tetB, sul2, tetA and tetX, while those in the receiving surface water were sul2, intI1 and sul1, and the concentrations of ARGs in the receiving bodies were higher than those in the other natural bodies by 1 to 2 orders of magnitude. In addition, the results of bivariate correlation analysis showed that the abundances of ARGs (tetC, tetW, sul1, sul2, intI1 and FOX) were in significant correlation with the concentrations of heavy metals (Cu, Zn, Ni and Cr) (p < 0.05). LTPs are more likely to be sources of ARGs than wastewater treatment plant (WWTP) and need to be focused on. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Presence, distribution, and diversity of iron-oxidizing bacteria at a landfill leachate-impacted groundwater surface water interface

    DEFF Research Database (Denmark)

    Yu, R.; Gan, P.; Mackay, A.A.

    2010-01-01

    We examined the presence of iron-oxidizing bacteria (IOB) at a groundwater surface water interface (GSI) impacted by reduced groundwater originating as leachate from an upgradient landfill. IOB enrichments and quantifications were obtained, at high vertical resolution, by an iron/oxygen opposing...... gradient cultivation method. The depth-resolved soil distribution profiles of water content, Fe2+, and total Fe indicated sharp gradients within the top 10 cm sediments of the GSI, where the IOB density was the highest. In addition, the vertical distribution of iron-reducing bacteria at the same sampling...

  18. New horizons in selective laser sintering surface roughness characterization

    Science.gov (United States)

    Vetterli, M.; Schmid, M.; Knapp, W.; Wegener, K.

    2017-12-01

    Powder-based additive manufacturing of polymers and metals has evolved from a prototyping technology to an industrial process for the fabrication of small to medium series of complex geometry parts. Unfortunately due to the processing of powder as a basis material and the successive addition of layers to produce components, a significant surface roughness inherent to the process has been observed since the first use of such technologies. A novel characterization method based on an elastomeric pad coated with a reflective layer, the Gelsight, was found to be reliable and fast to characterize surfaces processed by selective laser sintering (SLS) of polymers. With help of this method, a qualitative and quantitative investigation of SLS surfaces is feasible. Repeatability and reproducibility investigations are performed for both 2D and 3D areal roughness parameters. Based on the good results, the Gelsight is used for the optimization of vertical SLS surfaces. A model built on laser scanning parameters is proposed and after confirmation could achieve a roughness reduction of 10% based on the S q parameter. The Gelsight could be successfully identified as a fast, reliable and versatile surface topography characterization method as it applies to all kind of surfaces.

  19. Proton surface charge determination in Spodosol horizons with organically bound aluminum

    Science.gov (United States)

    Skyllberg, Ulf; Borggaard, Ole K.

    1998-05-01

    Net proton surface charge densities were determined in O, E, Bh, and Bs horizons of a sandy till, Spodosol from Denmark, by means of acid-base titration combined with ion adsorption in 0.005 M Ca(NO 3) 2 and independent permanent charge determination. The release of organic anions exceeded the adsorption of NO 3-, resulting in a desorption of anions in all horizons. Data were found to obey the law of balance between surface charges and adsorbed ions only when charges pertaining to Al and organic anions released during the titration experiments were accounted for, in addition to charges pertaining the potential determining ions (PDI) H + and OH - and the index ions Ca 2+ and NO 3-. It was furthermore shown that the point of zero net proton charge (PZNPC) in soils highly depends on the concentration of organically bound Al. Approaches previously used in soils, in which adsorbed Al n+ has been ignored (i.e., considered equivalent to nH + as a PDI), resulted in a PZNPC of 4.1 in the Bs horizon. If instead organically bound Al was accounted for as a counter-ion similar to 3/2Ca 2+, a PZNPC of 2.9 was obtained for the same Bs horizon. Based on PZNPC values estimated by the latter approach, combined with a weak-acid analog, it was shown that organic proton surface charges buffered pH with a similar intensity in the O, E, Bh, and Bs horizons of this study. Because the acidity of Al adsorbed to conjugate bases of soil organic acids is substantially weaker than the acidity of the corresponding protonated form of the organic acids, the point of zero net proton charge (PZNPC) will increase if the concentration of organically adsorbed Al increases at the expense of adsorbed H. This means that PZNPC values determined for soils with unknown concentrations of organically adsorbed Al are highly operational and not very meaningful as references.

  20. From Massively Parallel Algorithms and Fluctuating Time Horizons to Nonequilibrium Surface Growth

    International Nuclear Information System (INIS)

    Korniss, G.; Toroczkai, Z.; Novotny, M. A.; Rikvold, P. A.

    2000-01-01

    We study the asymptotic scaling properties of a massively parallel algorithm for discrete-event simulations where the discrete events are Poisson arrivals. The evolution of the simulated time horizon is analogous to a nonequilibrium surface. Monte Carlo simulations and a coarse-grained approximation indicate that the macroscopic landscape in the steady state is governed by the Edwards-Wilkinson Hamiltonian. Since the efficiency of the algorithm corresponds to the density of local minima in the associated surface, our results imply that the algorithm is asymptotically scalable. (c) 2000 The American Physical Society

  1. Horizon measures

    KAUST Repository

    Zhang, Eugene

    2016-11-28

    In this paper we seek to answer the following question: where do contour lines and visible contour lines (silhouette) tend to occur in a 3D surface. Our study leads to two novel shape descriptors, the horizon measure and the visible horizon measure, which we apply to the visualization of 3D shapes including archeological artifacts. In addition to introducing the shape descriptors, we also provide a closed-form formula for the horizon measure based on classical spherical geometry. To compute the visible horizon measure, which depends on the exact computation of the surface visibility function, we instead of provide an image-based approach which can process a model with high complexity within a few minutes.

  2. Optimization of the photoelectrocatalytic oxidation of landfill leachate using copper and nitrate co-doped TiO2 (Ti by response surface methodology.

    Directory of Open Access Journals (Sweden)

    Xiao Zhou

    Full Text Available In this paper, a statistically-based experimental design with response surface methodology (RSM was employed to examine the effects of functional conditions on the photoelectrocatalytic oxidation of landfill leachate using a Cu/N co-doped TiO2 (Ti electrode. The experimental design method was applied to response surface modeling and the optimization of the operational parameters of the photoelectro-catalytic degradation of landfill leachate using TiO2 as a photo-anode. The variables considered were the initial chemical oxygen demand (COD concentration, pH and the potential bias. Two dependent parameters were either directly measured or calculated as responses: chemical oxygen demand (COD removal and total organic carbon (TOC removal. The results of this investigation reveal that the optimum conditions are an initial pH of 10.0, 4377.98mgL-1 initial COD concentration and 25.0 V of potential bias. The model predictions and the test data were in satisfactory agreement. COD and TOC removals of 67% and 82.5%, respectively, were demonstrated. Under the optimal conditions, GC/MS showed 73 organic micro-pollutants in the raw landfill leachate which included hydrocarbons, aromatic compounds and esters. After the landfill leachate treatment processes, 38 organic micro-pollutants disappeared completely in the photoelectrocatalytic process.

  3. The surface elevation table: marker horizon method for measuring wetland accretion and elevation dynamics

    Science.gov (United States)

    Callaway, John C.; Cahoon, Donald R.; Lynch, James C.

    2014-01-01

    Tidal wetlands are highly sensitive to processes that affect their elevation relative to sea level. The surface elevation table–marker horizon (SET–MH) method has been used to successfully measure these processes, including sediment accretion, changes in relative elevation, and shallow soil processes (subsidence and expansion due to root production). The SET–MH method is capable of measuring changes at very high resolution (±millimeters) and has been used worldwide both in natural wetlands and under experimental conditions. Marker horizons are typically deployed using feldspar over 50- by 50-cm plots, with replicate plots at each sampling location. Plots are sampled using a liquid N2 cryocorer that freezes a small sample, allowing the handling and measurement of soft and easily compressed soils with minimal compaction. The SET instrument is a portable device that is attached to a permanent benchmark to make high-precision measurements of wetland surface elevation. The SET instrument has evolved substantially in recent decades, and the current rod SET (RSET) is widely used. For the RSET, a 15-mm-diameter stainless steel rod is pounded into the ground until substantial resistance is achieved to establish a benchmark. The SET instrument is attached to the benchmark and leveled such that it reoccupies the same reference plane in space, and pins lowered from the instrument repeatedly measure the same point on the soil surface. Changes in the height of the lowered pins reflect changes in the soil surface. Permanent or temporary platforms provide access to SET and MH locations without disturbing the wetland surface.

  4. Landfill leachate treatment using powdered activated carbon augmented sequencing batch reactor (SBR) process: Optimization by response surface methodology

    International Nuclear Information System (INIS)

    Aziz, Shuokr Qarani; Aziz, Hamidi Abdul; Yusoff, Mohd Suffian; Bashir, Mohammed J.K.

    2011-01-01

    In this study, landfill leachate was treated by using the sequencing batch reactor (SBR) process. Two types of the SBR, namely non-powdered activated carbon and powdered activated carbon (PAC-SBR) were used. The influence of aeration rate and contact time on SBR and PAC-SBR performances was investigated. Removal efficiencies of chemical oxygen demand (COD), colour, ammoniacal nitrogen (NH 3 -N), total dissolved salts (TDS), and sludge volume index (SVI) were monitored throughout the experiments. Response surface methodology (RSM) was applied for experimental design, analysis and optimization. Based on the results, the PAC-SBR displayed superior performance in term of removal efficiencies when compared to SBR. At the optimum conditions of aeration rate of 1 L/min and contact time of 5.5 h the PAC-SBR achieved 64.1%, 71.2%, 81.4%, and 1.33% removal of COD, colour, NH 3 -N, and TDS, respectively. The SVI value of PAC-SBR was 122.2 mL/g at optimum conditions.

  5. Landfill leachate treatment using powdered activated carbon augmented sequencing batch reactor (SBR) process: Optimization by response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Aziz, Shuokr Qarani [School of Civil Engineering, Universiti Sains Malaysia (USM), 14300 Nibong Tebal, Penang (Malaysia); Aziz, Hamidi Abdul, E-mail: cehamidi@eng.usm.my [School of Civil Engineering, Universiti Sains Malaysia (USM), 14300 Nibong Tebal, Penang (Malaysia); Yusoff, Mohd Suffian; Bashir, Mohammed J.K. [School of Civil Engineering, Universiti Sains Malaysia (USM), 14300 Nibong Tebal, Penang (Malaysia)

    2011-05-15

    In this study, landfill leachate was treated by using the sequencing batch reactor (SBR) process. Two types of the SBR, namely non-powdered activated carbon and powdered activated carbon (PAC-SBR) were used. The influence of aeration rate and contact time on SBR and PAC-SBR performances was investigated. Removal efficiencies of chemical oxygen demand (COD), colour, ammoniacal nitrogen (NH{sub 3}-N), total dissolved salts (TDS), and sludge volume index (SVI) were monitored throughout the experiments. Response surface methodology (RSM) was applied for experimental design, analysis and optimization. Based on the results, the PAC-SBR displayed superior performance in term of removal efficiencies when compared to SBR. At the optimum conditions of aeration rate of 1 L/min and contact time of 5.5 h the PAC-SBR achieved 64.1%, 71.2%, 81.4%, and 1.33% removal of COD, colour, NH{sub 3}-N, and TDS, respectively. The SVI value of PAC-SBR was 122.2 mL/g at optimum conditions.

  6. Leachate characterization and identification of dominant pollutants using leachate pollution index for an uncontrolled landfill site

    Directory of Open Access Journals (Sweden)

    S. De

    2016-03-01

    Full Text Available Landfill leachates are potential threats for environmental degradation. This study was conducted to determine the leachate quality, to identify the dominant pollutants and to evaluate the leachate pollution potential of an active and closed dumping ground of an uncontrolled municipal solid waste landfill site in Kolkata, India using leachate pollution index. The results of the physico-chemical and biological analyses of leachate indicated that landfill site was in its methanogenic phase. Among the analysed leachate pollutants, TDS, BOD5, COD, TKN, NH3-N, Cl¯, TCB, Pb, and Hg surpassed the leachate discharge standards for inland surface water as specified by the municipal solid waste (Management and Handling Rules, 2013 for both the dumping grounds. Moreover the concentrations of total Cr and Zn also exceeded the leachate disposal standards for the active dumping ground. The leachate pollution potentialities of both the active and closed dumping grounds were comparable as the overall LPI obtained 34.02 and 31.80 respectively. The overall LPI, LPI organic (LPIor, LPI inorganic (LPIin and LPI heavy metals (LPIhm of both the dumping grounds largely exceeded the LPI and sub-LPI values for treated leachate before disposal to the inland surface water. In terms of the individual pollution rating, total coliform bacteria, TKN, NH3-N and Hg were identified as the dominant pollutants and major contributing factors for the leachate pollution potential.

  7. Partial Photochemical Oxidation Was a Dominant Fate of Deepwater Horizon Surface Oil.

    Science.gov (United States)

    Ward, Collin P; Sharpless, Charles M; Valentine, David L; French-McCay, Deborah P; Aeppli, Christoph; White, Helen K; Rodgers, Ryan P; Gosselin, Kelsey M; Nelson, Robert K; Reddy, Christopher M

    2018-02-20

    Following the Deepwater Horizon (DWH) blowout in 2010, oil floated on the Gulf of Mexico for over 100 days. In the aftermath of the blowout, substantial accumulation of partially oxidized surface oil was reported, but the pathways that formed these oxidized residues are poorly constrained. Here we provide five quantitative lines of evidence demonstrating that oxidation by sunlight largely accounts for the partially oxidized surface oil. First, residence time on the sunlit sea surface, where photochemical reactions occur, was the strongest predictor of partial oxidation. Second, two-thirds of the partial oxidation from 2010 to 2016 occurred in less than 10 days on the sunlit sea surface, prior to coastal deposition. Third, multiple diagnostic biodegradation indices, including octadecane to phytane, suggest that partial oxidation of oil on the sunlit sea surface was largely driven by an abiotic process. Fourth, in the laboratory, the dominant photochemical oxidation pathway of DWH oil was partial oxidation to oxygenated residues rather than complete oxidation to CO 2 . Fifth, estimates of partial photo-oxidation calculated with photochemical rate modeling overlap with observed oxidation. We suggest that photo-oxidation of surface oil has fundamental implications for the response approach, damage assessment, and ecosystem restoration in the aftermath of an oil spill, and that oil fate models for the DWH spill should be modified to accurately reflect the role of sunlight.

  8. Spatial distribution of heterocyclic organic matter compounds at macropore surfaces in Bt-horizons

    Science.gov (United States)

    Leue, Martin; Eckhardt, Kai-Uwe; Gerke, Horst H.; Ellerbrock, Ruth H.; Leinweber, Peter

    2017-04-01

    The illuvial Bt-horizon of Luvisols is characterized by coatings of clay and organic matter (OM) at the surfaces of cracks, biopores and inter-aggregate spaces. The OM composition of the coatings that originate from preferential transport of suspended matter in macropores determines the physico-chemical properties of the macropore surfaces. The analysis of the spatial distribution of specific OM components such as heterocyclic N-compounds (NCOMP) and benzonitrile and naphthalene (BN+NA) could enlighten the effect of macropore coatings on the transport of colloids and reactive solutes during preferential flow and on OM turnover processes in subsoils. The objective was to characterize the mm-to-cm scale spatial distribution of NCOMP and BN+NA at intact macropore surfaces from the Bt-horizons of two Luvisols developed on loess and glacial till. In material manually separated from macropore surfaces the proportions of NCOMP and BN+NA were determined by pyrolysis-field ionization mass spectrometry (Py-FIMS). These OM compounds, likely originating from combustion residues, were found increased in crack coatings and pinhole fillings but decreased in biopore walls (worm burrows and root channels). The Py-FIMS data were correlated with signals from C=O and C=C groups and with signals from O-H groups of clay minerals as determined by Fourier transform infrared spectroscopy in diffuse reflectance mode (DRIFT). Intensive signals of C15 to C17 alkanes from long-chain alkenes as main components of diesel and diesel exhaust particulates substantiated the assumption that burning residues were prominent in the subsoil OM. The spatial distribution of NCOMP and BN+NA along the macropores was predicted by partial least squares regression (PLSR) using DRIFT mapping spectra from intact surfaces and was found closely related to the distribution of crack coatings and pinholes. The results emphasize the importance of clay coatings in the subsoil to OM sorption and stabilization

  9. Where the oil from surface and subsurface plumes deposited during/after Deepwater Horizon oil spill?

    Science.gov (United States)

    Yan, B.

    2016-02-01

    The Deepwater Horizon (DwH) oil spill released an estimated 4.9 million barrels (about 200 million gallons) of crude oil into the Gulf of Mexico between April 20, 2010 and July 15, 2010. Though Valentine et al. has linked the elevated oil components in some sediments with the subsurface plume, the sites with fallout from the ocean surface plume has not been identified. This piece of information is critical not only for a comprehensive scientific understanding of the ecosystem response and fate of spill-related pollutants, but also for litigation purposes and future spill response and restoration planning. In this study we focus on testing the hypothesis that marine snow from the surface plume were deposited on the sea floor over a broad area. To do so, we use publicly available data generated as part of the ongoing Natural Resource Damage Assessment (NRDA) process to assess the spatial distribution of petroleum hydrocarbons in the water column and deep-ocean sediments of the Gulf of Mexico. Sensitive hydrocarbon markers are used to differentiate hydrocarbons from surface plume, deep subsurface plume, and in-situ burning. Preliminary results suggest the overlapping but different falling sites of these plumes and the sedimentation process was controlled by various biological, chemical, and physical factors.

  10. Revisiting Vaidya Horizons

    Directory of Open Access Journals (Sweden)

    Alex B. Nielsen

    2014-02-01

    Full Text Available In this study, we located and compared different types of horizons in the spherically symmetric Vaidya solution. The horizons we found were trapping horizons, which can be null, timelike, or spacelike, null surfaces with constant area change and also conformal Killing horizons. The conformal Killing horizons only exist for certain choices of the mass function. Under a conformal transformation, the conformal Killing horizons can be mapped into true Killing horizons. This allows conclusions drawn in the dynamical Vaidya spacetime to be related to known properties of static spacetimes. We found the conformal factor that performs this transformation and wrote the new metric in explicitly static coordinates. Using this construction we found that the tunneling argument for Hawking radiation does not umabiguously support Hawking radiation being associated with the trapping horizon. We also used this transformation to derive the form of the surface gravity for a class of physical observers in Vaidya spacetimes.

  11. Seasonal dynamics in leachate hydrochemistry and natural attentuation in surface run-off waste from a tropical landfill

    NARCIS (Netherlands)

    Mangimbulude, J.C.; van Breukelen, B.M.; Krave, A.S.; van Straalen, N.M.; Roling, W.F.M.

    2009-01-01

    Open waste dump systems are still widely used in Indonesia. The Jatibarang landfill receives 650-700 tons of municipal waste per day from the city of Semarang, Central Java. Some of the leachate from the landfill flows via several natural and collection ponds to a nearby river. The objectives of the

  12. Texture and geochemistry of surface horizons of Arctic soils from a non-glaciated catchment, SW Spitsbergen

    Directory of Open Access Journals (Sweden)

    Szymański Wojciech

    2016-09-01

    Full Text Available Physical and chemical properties of Arctic soils and especially the properties of surface horizons of the soils are very important because they are responsible for the rate and character of plant colonization, development of vegetation cover, and influence the rate and depth of thawing of soils and development of active layer of permafrost during summer. The main aim of the present study is to determine and explain the spatial diversity of selected physical and chemical properties of surface horizons of Arctic soils from the non-glaciated Fuglebekken catchment located in the Hornsund area (SW Spitsbergen by means of geostatistical approach. Results indicate that soil surface horizons in the Fuglebekken catchment are characterized by highly variable physical and chemical properties due to a heterogeneous parent material (marine sediments, moraine, rock debris, tundra vegetation types, and non-uniform influence of seabirds. Soils experiencing the strongest influence of seabird guano have a lower pH than other soils. Soils developed on the lateral moraine of the Hansbreen glacier have the highest pH due to the presence of carbonates in the parent material and a lack or presence of a poorly developed and discontinuous A horizon. The soil surface horizons along the coast of the Hornsund exhibit the highest content of the sand fraction and SiO2. The surface of soils occurring at the foot of the slope of Ariekammen Ridge is characterized by the highest content of silt and clay fractions as well as Al2O3, Fe2O3, and K2O. Soils in the central part of the Fuglebekken catchment are depleted in CaO, MgO, and Na2O in comparison with soils in the other sampling sites, which indicates the highest rate of leaching in this part of the catchment.

  13. Mechanism of formation of humus coatings on mineral surfaces 1. Evidence for multidentate binding of organic acids from compost leachate on alumina

    Science.gov (United States)

    Wershaw, R. L.; Leenheer, J.A.; Sperline, R.P.; Song, Yuan; Noll, L.A.; Melvin, R.L.; Rigatti, G.P.

    1995-01-01

    Measurements of the infrared linear dichroism of carboxylate groups of organic acids from compost leachate adsorbed to an alumina surface and the enthalpy of adsorption of this reaction have been made. The linear dichroism measurements indicated that the carboxylate groups are not free to rotate. This limited rotation probably results from bidentate binding of the carboxylate groups. The molar enthalpy of adsorption of the acids is approximately −100 kJ mol−1. This high value for enthalpy of adsorption may best be explained by assuming that two or more carboxylate groups on a single dissolved organic carbon (DOC) molecule coordinate to the surficial aluminium ions.

  14. Quantification of small-scale physicochemical properties of intact macropore surfaces in Bt-horizons of Luvisols

    Science.gov (United States)

    Leue, Martin; Gerke, Horst H.

    2017-04-01

    During preferential flow in structured soils, the interaction of percolating water and reactive solutes with the soil matrix is mostly restricted to surfaces of preferential flow paths which affect mass exchange processes by the physical and chemical properties. These properties can strongly differ from bulk soil properties with respect to texture, organic matter (OM), pore geometry, density, and porosity. The aim of our work was to identify and to quantify effective macropore properties which concurrently are appropriate to represent physical mechanisms for entire soil horizons with respect to preferential flow. We studied physical and chemical properties of intact surfaces of soil aggregates, biopores (root channels, worm burrows), and coated cracks from Luvisol Bt-horizons. The spatial distribution of the OM composition and related physical properties such as wettability, the organic carbon content, and the cation exchange capacity of these macropores as characterized by DRIFT spectroscopy and complementary techniques were found spatially distributed at the mm-scale. Differences could be observed for loess and glacial till as parent materials, land use, and macropore types, in particular for cracks and biopores. The geometrical properties (pore volume, diameter, surfaces area, connectivity, and tortuosity) of all potentially available macropores, in particular the differences between cracks and biopores, were quantified in large soil columns using X-ray computed tomography (µCT). Dye tracer experiments at the cm-to-m-scale showed substrate-specific and macropore-specific differences between the active preferential flow paths. In a summarizing step we aim to combine the chemical and physical surface properties with the geometrical properties of the macropores in order to estimate the effects of the surface properties on preferential flow in Bt-horizons. The specific surface areas and chemical compositions may help explain differences in the staining patterns

  15. HORIZON SENSING

    Energy Technology Data Exchange (ETDEWEB)

    Larry G. Stolarczyk

    2003-03-18

    appropriately. The Horizon Sensor program began development in 1998 and experienced three major design phases. The final version, termed HS-3, was commissioned in 2000 with the assistance of the DOE-Mining Industry of the Future program, commercialized in 2002, and has been used 14 times in 12 different mines within the United States. The Horizon Sensor has applications in both underground and surface mining operations. This technology is primarily used in the coal industry, but is also used to mine trona and potash. All horizon sensor components have Mine Safety and Health Administration (MSHA) (United States) and IEC (International) certification. Horizon Sensing saves energy by maximizing cutting efficiency, cutting only desired material. This desired material is cleaner fuel, therefore reducing pollutants to the atmosphere when burned and burning more efficiently. Extracting only desired material increases productivity by reducing or eliminating the cleaning step after extraction. Additionally, this technology allows for deeper mining, resulting in more material gained from one location. The remote sensing tool allows workers to operate the machinery away from the hazards of cutting coal, including noise, breathing dust and gases, and coal and rock splintering and outbursts. The HS program has primarily revolved around the development of the technology. However, the end goal of the program has always been the commercialization of the technology and only within the last 2 years of the program has this goal been realized. Real-time horizon sensing on mining machines is becoming an industry tool. Detailed monitoring of system function, user experience, and mining benefits is ongoing.

  16. Bacterial communities of surface and deep hydrocarbon-contaminated waters of the Deepwater Horizon oil spill

    Science.gov (United States)

    Yang, T.; Nigro, L. M.; McKay, L.; Ziervogel, K.; Gutierrez, T.; Teske, A.

    2010-12-01

    We performed a 16S rRNA gene sequencing survey of bacterial communities within oil-contaminated surface water, deep hydrocarbon plume water, and deep water samples above and below the plume to determine spatial and temporal patterns of oil-degrading bacteria growing in response to the Deepwater Horizon oil leak. In addition, we are reporting 16S rRNA sequencing results from time series incubation, enrichment and cultivation experiments. Surface oil slick samples were collected 3 nautical miles from ground zero, (5/6/10, RV Pelican) and were added to uncontaminated surface water (collected within a 30 nautical mile radius of ground zero, 5/6/10 - 5/9/10, RV Pelican). This mixture was incubated for 20 days in a rolling bottle at 25°C. 16S rRNA clone libraries from marine snow-like microbial flocs that had formed during the incubation yielded a highly diverse bacterial community, predominately composed of the Alpha- and Gammaproteobacteria, and a smaller number of Planktomycetes and other bacterial lineages. The most frequently recovered proteobacterial sequences were closely related to cultured species of the genus Cycloclasticus, specialists in aerobic oxidation of aromatic hydrocarbons. These time series incubation results will be compared to the microbial community structure of contaminated surface water, sampled on the same cruise with RV Pelican (5/6/10-5/9/10) and frozen immediately. Stable isotope probing (SIP) experiments with C13-labelled alkanes and polycyclic aromatic substrates and gulf water samples have yielded different enrichments. With naphthalene, predominantly Alteromonas-related clones and a smaller share of Cycloclasticus clones were recovered; phenanthrene yielded predominantly clones related to Cycloclasticus, and diverse other Gamma- and Alphaproteobacteria. Analyses of SIP experiments with hexadecane are in progress. The microbial community composition of the deep hydrocarbon plume was characterized using water column profile samples taken

  17. Revisiting event horizon finders

    International Nuclear Information System (INIS)

    Cohen, Michael I; Pfeiffer, Harald P; Scheel, Mark A

    2009-01-01

    Event horizons are the defining physical features of black hole spacetimes, and are of considerable interest in studying black hole dynamics. Here, we reconsider three techniques to find event horizons in numerical spacetimes: integrating geodesics, integrating a surface, and integrating a level-set of surfaces over a volume. We implement the first two techniques and find that straightforward integration of geodesics backward in time is most robust. We find that the exponential rate of approach of a null surface towards the event horizon of a spinning black hole equals the surface gravity of the black hole. In head-on mergers we are able to track quasi-normal ringing of the merged black hole through seven oscillations, covering a dynamic range of about 10 5 . Both at late times (when the final black hole has settled down) and at early times (before the merger), the apparent horizon is found to be an excellent approximation of the event horizon. In the head-on binary black hole merger, only some of the future null generators of the horizon are found to start from past null infinity; the others approach the event horizons of the individual black holes at times far before merger.

  18. Overlap between Atlantic bluefin tuna spawning grounds and observed Deepwater Horizon surface oil in the northern Gulf of Mexico.

    Science.gov (United States)

    Muhling, B A; Roffer, M A; Lamkin, J T; Ingram, G W; Upton, M A; Gawlikowski, G; Muller-Karger, F; Habtes, S; Richards, W J

    2012-04-01

    The 2010 Deepwater Horizon oil spill impacted the northern Gulf of Mexico (GOM) during the spring spawning season of Atlantic bluefin tuna (BFT). Overlap between BFT spawning habitat and surface oil in the northern GOM was examined using satellite-derived estimates of oil coverage, and spawning habitat models. Results suggested that although eggs and larvae were likely impacted by oil-contaminated waters in the eastern GOM, high abundances of larvae were located elsewhere, especially in the western GOM. Overall, less than 10% of BFT spawning habitat was predicted to have been covered by surface oil, and less than 12% of larval BFT were predicted to have been located within contaminated waters in the northern GOM, on a weekly basis. Our results provide preliminary but important initial estimates of the effects of the spill on larval BFT mortality, as concern continues over the appropriate management responses to impacts of the spill. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Pluto's Global Surface Composition Through Pixel-by-Pixel Hapke Modeling of New Horizons Ralph LEISA Data

    Science.gov (United States)

    Protopapa, S.; Grundy, W. M.; Reuter, D. C.; Hamilton, D. P.; Dalle Ore, C. M.; Cook, J. C.; Cruikshank, D. P.; Schmitt, B.; Philippe, S.; Quirico, E.; hide

    2016-01-01

    On July 14th 2015, NASA's New Horizons mission gave us an unprecedented detailed view of the Pluto system. The complex compositional diversity of Pluto's encounter hemisphere was revealed by the Ralph/LEISA infrared spectrometer on board of New Horizons. We present compositional maps of Pluto defining the spatial distribution of the abundance and textural properties of the volatiles methane and nitrogen ices and non-volatiles water ice and tholin. These results are obtained by applying a pixel-by-pixel Hapke radiative transfer model to the LEISA scans. Our analysis focuses mainly on the large scale latitudinal variations of methane and nitrogen ices and aims at setting observational constraints to volatile transport models. Specifically, we find three latitudinal bands: the first, enriched in methane, extends from the pole to 55degN, the second dominated by nitrogen, continues south to 35 degN, and the third, com- posed again mainly of methane, reaches 20 degN. We demonstrate that the distribution of volatiles across these surface units can be explained by differences in insolation over the past few decades. The latitudinal pattern is broken by Sputnik Planitia, a large reservoir of volatiles, with nitrogen playing the most important role. The physical properties of methane and nitrogen in this region are suggestive of the presence of a cold trap or possible volatile stratification. Furthermore our modeling results point to a possible sublimation transport of nitrogen from the northwest edge of Sputnik Planitia toward the south.

  20. Rapid microbial respiration of oil from the Deepwater Horizon spill in offshore surface waters of the Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, Bethanie R; Reddy, Christopher M; Carmichael, Catherine A; Longnecker, Krista; Van Mooy, Benjamin A S [Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole (United States); Camilli, Richard, E-mail: bvanmooy@whoi.edu [Department of Applied Ocean Physics and Engineering, Woods Hole Oceanographic Institution, Woods Hole (United States)

    2011-07-15

    The Deepwater Horizon oil spill was one of the largest oil spills in history, and the fate of this oil within the Gulf of Mexico ecosystem remains to be fully understood. The goal of this study-conducted in mid-June of 2010, approximately two months after the oil spill began-was to understand the key role that microbes would play in the degradation of the oil in the offshore oligotrophic surface waters near the Deepwater Horizon site. As the utilization of organic carbon by bacteria in the surface waters of the Gulf had been previously shown to be phosphorus limited, we hypothesized that bacteria would be unable to rapidly utilize the oil released from the Macondo well. Although phosphate was scarce throughout the sampling region and microbes exhibited enzymatic signs of phosphate stress within the oil slick, microbial respiration within the slick was enhanced by approximately a factor of five. An incubation experiment to determine hydrocarbon degradation rates confirmed that a large fraction of this enhanced respiration was supported by hydrocarbon degradation. Extrapolating our observations to the entire area of the slick suggests that microbes had the potential to degrade a large fraction of the oil as it arrived at the surface from the well. These observations decidedly refuted our hypothesis. However, a concomitant increase in microbial abundance or biomass was not observed in the slick, suggesting that microbial growth was nutrient limited; incubations amended with nutrients showed rapid increases in cell number and biomass, which supported this conclusion. Our study shows that the dynamic microbial community of the Gulf of Mexico supported remarkable rates of oil respiration, despite a dearth of dissolved nutrients.

  1. Rapid microbial respiration of oil from the Deepwater Horizon spill in offshore surface waters of the Gulf of Mexico

    International Nuclear Information System (INIS)

    Edwards, Bethanie R; Reddy, Christopher M; Carmichael, Catherine A; Longnecker, Krista; Van Mooy, Benjamin A S; Camilli, Richard

    2011-01-01

    The Deepwater Horizon oil spill was one of the largest oil spills in history, and the fate of this oil within the Gulf of Mexico ecosystem remains to be fully understood. The goal of this study-conducted in mid-June of 2010, approximately two months after the oil spill began-was to understand the key role that microbes would play in the degradation of the oil in the offshore oligotrophic surface waters near the Deepwater Horizon site. As the utilization of organic carbon by bacteria in the surface waters of the Gulf had been previously shown to be phosphorus limited, we hypothesized that bacteria would be unable to rapidly utilize the oil released from the Macondo well. Although phosphate was scarce throughout the sampling region and microbes exhibited enzymatic signs of phosphate stress within the oil slick, microbial respiration within the slick was enhanced by approximately a factor of five. An incubation experiment to determine hydrocarbon degradation rates confirmed that a large fraction of this enhanced respiration was supported by hydrocarbon degradation. Extrapolating our observations to the entire area of the slick suggests that microbes had the potential to degrade a large fraction of the oil as it arrived at the surface from the well. These observations decidedly refuted our hypothesis. However, a concomitant increase in microbial abundance or biomass was not observed in the slick, suggesting that microbial growth was nutrient limited; incubations amended with nutrients showed rapid increases in cell number and biomass, which supported this conclusion. Our study shows that the dynamic microbial community of the Gulf of Mexico supported remarkable rates of oil respiration, despite a dearth of dissolved nutrients.

  2. Horizon holography

    Science.gov (United States)

    Sachs, Ivo; Solodukhin, Sergey N.

    2001-12-01

    A holographic correspondence between horizon data and space-time physics is investigated. We find similarities with the AdS-CFT correspondence, based on the observation that the optical metric near the horizon describes a Euclidean, asymptotically anti-de Sitter space. This picture emerges for a wide class of static space-times with a nondegenerate horizon, including Schwarzschild black holes as well as de Sitter space-time. We reveal an asymptotic conformal symmetry at the horizon. We compute the conformal weights and 2-point functions for a scalar perturbation and discuss possible connections with a conformal field theory located on the horizon. We then reconstruct the scalar field and the metric from the data given on the horizon. We show that the solution for the metric in the bulk is completely determined in terms of a specified metric on the horizon. From the general relativity point of view our solutions present a new class of space-time metrics with nonspherical horizons. The horizon entropy associated with these solutions is also discussed.

  3. Phytoremediation of landfill leachate

    International Nuclear Information System (INIS)

    Jones, D.L.; Williamson, K.L.; Owen, A.G.

    2006-01-01

    Leachate emissions from landfill sites are of concern, primarily due to their toxic impact when released unchecked into the environment, and the potential for landfill sites to generate leachate for many hundreds of years following closure. Consequently, economically and environmentally sustainable disposal options are a priority in waste management. One potential option is the use of soil-plant based remediation schemes. In many cases, using either trees (including short rotation coppice) or grassland, phytoremediation of leachate has been successful. However, there are a significant number of examples where phytoremediation has failed. Typically, this failure can be ascribed to excessive leachate application and poor management due to a fundamental lack of understanding of the plant-soil system. On balance, with careful management, phytoremediation can be viewed as a sustainable, cost effective and environmentally sound option which is capable of treating 250 m 3 ha -1 yr -1 . However, these schemes have a requirement for large land areas and must be capable of responding to changes in leachate quality and quantity, problems of scheme establishment and maintenance, continual environmental monitoring and seasonal patterns of plant growth. Although the fundamental underpinning science is well understood, further work is required to create long-term predictive remediation models, full environmental impact assessments, a complete life-cycle analysis and economic analyses for a wide range of landfill scenarios

  4. Organic halogens in landfill leachates

    DEFF Research Database (Denmark)

    Grøn, C.; Christensen, J. B.; Jensen, Dorthe Lærke

    2000-01-01

    Using a group parameter, total organic halogens (TOX), high TOX concentrations were found in leachates and leachate contaminated groundwaters at two Danish mixed sanitary and hazardous waste sites. With commonly used screening procedures for organic contaminants, the individual halogenated organi...

  5. Review of existing landfill leachate production models

    International Nuclear Information System (INIS)

    Khan, T.A.

    2000-01-01

    The protection of water resources is a fundamental consideration in managing landfill operations. Landfill sites should be designed and operated so as to control leachate production and hence minimize the risk of surface and ground water pollution. A further important development is the use of computer models to estimate the production of leachate from landfill sites. It is revealed from the literature that a number of landfill leachate management model lave been development in recent years. These models allow different engineering schemes to be evaluated and are essential tools for design and operation managements of modern landfills. This paper describes a review of such models mainly focused on their theory, practicability, data requirements, suitability to real situation and usefulness. An evaluation of these models identifies. (author)

  6. Organic Over-the-Horizon Targeting for the 2025 Surface Fleet

    Science.gov (United States)

    2015-06-01

    System -Investing time and money into a system that cannot evolve with a changing threat -Having a system that is unable to function in an A2...individual surface combatant in the prosecution of an OTH target, exogenous assets will not be part of SEA-21A SoS design recommendation to address the

  7. Loss of surface horizon of an irrigated soil detected by radiometric images of normalized difference vegetation index.

    Science.gov (United States)

    Fabian Sallesses, Leonardo; Aparicio, Virginia Carolina; Costa, Jose Luis

    2017-04-01

    The use of the soil in the Humid Pampa of Argentina has changed since the mid-1990s from agricultural-livestock production (that included pastures with direct grazing) to a purely agricultural production. Also, in recent years the area under irrigation by central pivot has been increased to 150%. The waters used for irrigation are sodium carbonates. The combination of irrigation and rain increases the sodium absorption ratio of soil (SARs), consequently raising the clay dispersion and reducing infiltration. This implies an increased risk of soil loss. A reduction in the development of white clover crop (Trifolium repens L.) was observed at an irrigation plot during 2015 campaign. The clover was planted in order to reduce the impact of two maize (Zea mays L.) campaigns under irrigation, which had increased soil SAR and deteriorated soil structure. SPOT-5 radiometric normalized difference vegetation index (NDVI) images were used to determine two zones of high and low production. In each zone, four random points were selected for further geo-referenced field sampling. Two geo-referenced measures of effective depth and surface soil sampling were carried out in each point. Texture of soil samples was determined by Pipette Method of Sedimentation Analysis. Data exploratory analysis showed that low production zone had a media effective depth = 80 cm and silty clay loam texture, while high production zone had a media effective depth > 140 cm and silt loam texture. The texture class of the low production zone did not correspond to prior soil studies carried out by the INTA (National Institute of Agricultural Technology), which showed that those soil textures were silt loam at surface and silty clay loam at sub-surface. The loss of the A horizon is proposed as a possible explanation, but further research is required. Besides, the need of a soil cartography actualization, which integrates new satellite imaging technologies and geo-referenced measurements with soil sensors is

  8. Effects of coal leachates on fish spermatogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, R.C

    1987-01-01

    The use of coal as a fuel source for power plants often involves the storage of coal on the plant site. Coal stored in this manner is subject to leaching by rain or groundwater, and the leachates may seep into surface waters. Coal leachates were examined for toxic effects on fish spermatogenesis. Nonbreeding mummichogs, Fundulus heteroclitus, were induced to enter breeding condition in the laboratory by exposure to 20{degree}C and a photoperiod of 16L:8D for 6 weeks. During this 6-weeks period, mummichogs were dosed in static exposure tanks with water extracts of coal (leachates). Chi-square analysis and Z test of proportions revealed a significant reduction in sperm production by fish exposed to some, but not all, coal leachates. This reduction was as much as 40-fold and occurred in a dose-dependent manner. Ordinarily, nonbreeding mummichogs collected immediately after the breeding season will not enter breeding condition in response to 16L:8D and 20{degree}C. Exposure of these photo-insensitive mummichogs to coal leachates under long photoperiod conditions for 8 weeks resulted in a significant increase in sperm production. Analysis of weekly sperm production by mummichogs from six field populations, either adjacent to or 2 miles upstream from coal-fired power plants, did not reveal significant differences during the breeding season. However, this sperm production was less than 1/10 that of a mummichog field population sampled concomitantly at the Chesapeake Bay Institute. The reduced sperm levels could not be related to reproductive toxin(s) contained in coal leachate. 13 refs., 1 figs., 3 tabs.

  9. Maritime over the Horizon Sensor Integration: High Frequency Surface-Wave-Radar and Automatic Identification System Data Integration Algorithm.

    Science.gov (United States)

    Nikolic, Dejan; Stojkovic, Nikola; Lekic, Nikola

    2018-04-09

    To obtain the complete operational picture of the maritime situation in the Exclusive Economic Zone (EEZ) which lies over the horizon (OTH) requires the integration of data obtained from various sensors. These sensors include: high frequency surface-wave-radar (HFSWR), satellite automatic identification system (SAIS) and land automatic identification system (LAIS). The algorithm proposed in this paper utilizes radar tracks obtained from the network of HFSWRs, which are already processed by a multi-target tracking algorithm and associates SAIS and LAIS data to the corresponding radar tracks, thus forming an integrated data pair. During the integration process, all HFSWR targets in the vicinity of AIS data are evaluated and the one which has the highest matching factor is used for data association. On the other hand, if there is multiple AIS data in the vicinity of a single HFSWR track, the algorithm still makes only one data pair which consists of AIS and HFSWR data with the highest mutual matching factor. During the design and testing, special attention is given to the latency of AIS data, which could be very high in the EEZs of developing countries. The algorithm is designed, implemented and tested in a real working environment. The testing environment is located in the Gulf of Guinea and includes a network of HFSWRs consisting of two HFSWRs, several coastal sites with LAIS receivers and SAIS data provided by provider of SAIS data.

  10. Physical State and Distribution of Materials at the Surface of Pluto from New Horizons LEISA Imaging Spectrometer

    Science.gov (United States)

    Schmitt, B.; Philippe, S.; Grundy, W. M.; Reuter, D. C.; Cote, R.; Quirico, E.; Protopappa, S.; Young, L. A.; Binzel, R. P.; Cook, J. C.; hide

    2016-01-01

    From Earth based observations Pluto is known to be the host of N2, CH4 and CO ices and also a dark red material. Very limited spatial distribution information is available from rotational visible and near-infrared spectral curves obtained from hemispheric measurements. In July 2015 the New Horizons spacecraft reached Pluto and its satellite system and recorded a large set of data. The LEISA spectro-imager of the RALPH instruments are dedicated to the study of the composition and physical state of the materials composing the surface. In this paper we report a study of the distribution and physical state of the ices and non-ice materials on Pluto's illuminated surface and their mode and degree of mixing. Principal Component analysis as well as various specific spectral indicators and correlation plots are used on the first set of 2 high resolution spectro-images from the LEISA instrument covering the whole illuminated face of Pluto at the time of the New Horizons encounter. Qualitative distribution maps have been obtained for the 4 main condensed molecules, N2, CH4, CO, H2O as well as for the visible-dark red material. Based on specific spectral indicators, using either the strength or the position of absorption bands, these 4 molecules are found to indicate the presence of 3 different types of ices: N2-rich:CH4:CO ices, CH4-rich(:CO:N2?) ices and H2O ice. The mixing lines between these ices and with the dark red material are studied using scatter plots between the various spectral indicators. CH4 is mixed at the molecular level with N2, most probably also with CO, thus forming a ternary molecular mixture that follows its phase diagram with low solubility limits. The occurrence of a N2-rich - CH4-rich ices mixing line associated with a progressive decrease of the CO/CH4 ratio tells us that a fractionation sublimation sequence transforms one type of ice to the other forming either a N2-rich - CH4-rich binary mixture at the surface or an upper CH4-rich ice crust that

  11. Physical state and distribution of materials at the surface of Pluto from New Horizons LEISA imaging spectrometer

    Science.gov (United States)

    Schmitt, B.; Philippe, S.; Grundy, W. M.; Reuter, D. C.; Côte, R.; Quirico, E.; Protopapa, S.; Young, L. A.; Binzel, R. P.; Cook, J. C.; Cruikshank, D. P.; Dalle Ore, C. M.; Earle, A. M.; Ennico, K.; Howett, C. J. A.; Jennings, D. E.; Linscott, I. R.; Lunsford, A. W.; Olkin, C. B.; Parker, A. H.; Parker, J. Wm.; Singer, K. N.; Spencer, J. R.; Stansberry, J. A.; Stern, S. A.; Tsang, C. C. C.; Verbiscer, A. J.; Weaver, H. A.; New Horizons Science Team

    2017-05-01

    From Earth based observations Pluto is known to be the host of N2, CH4 and CO ices and also a dark red material. Very limited spatial distribution information is available from rotational visible and near-infrared spectral curves obtained from hemispheric measurements. In July 2015 the New Horizons spacecraft reached Pluto and its satellite system and recorded a large set of data. The LEISA spectro-imager of the RALPH instruments are dedicated to the study of the composition and physical state of the materials composing the surface. In this paper we report a study of the distribution and physical state of the ices and non-ice materials on Pluto's illuminated surface and their mode and degree of mixing. Principal Component analysis as well as various specific spectral indicators and correlation plots are used on the first set of 2 high resolution spectro-images from the LEISA instrument covering the whole illuminated face of Pluto at the time of the New Horizons encounter. Qualitative distribution maps have been obtained for the 4 main condensed molecules, N2, CH4, CO, H2O as well as for the visible-dark red material. Based on specific spectral indicators, using either the strength or the position of absorption bands, these 4 molecules are found to indicate the presence of 3 different types of ices: N2-rich:CH4:CO ices, CH4-rich(:CO:N2?) ices and H2O ice. The mixing lines between these ices and with the dark red material are studied using scatter plots between the various spectral indicators. CH4 is mixed at the molecular level with N2, most probably also with CO, thus forming a ternary molecular mixture that follows its phase diagram with low solubility limits. The occurrence of a N2-rich - CH4-rich ices mixing line associated with a progressive decrease of the CO/CH4 ratio tells us that a fractionation sublimation sequence transforms one type of ice to the other forming either a N2-rich - CH4-rich binary mixture at the surface or an upper CH4-rich ice crust that

  12. Microbial activities and dissolved organic matter dynamics in oil-contaminated surface seawater from the Deepwater Horizon oil spill site.

    Directory of Open Access Journals (Sweden)

    Kai Ziervogel

    Full Text Available The Deepwater Horizon oil spill triggered a complex cascade of microbial responses that reshaped the dynamics of heterotrophic carbon degradation and the turnover of dissolved organic carbon (DOC in oil contaminated waters. Our results from 21-day laboratory incubations in rotating glass bottles (roller bottles demonstrate that microbial dynamics and carbon flux in oil-contaminated surface water sampled near the spill site two weeks after the onset of the blowout were greatly affected by activities of microbes associated with macroscopic oil aggregates. Roller bottles with oil-amended water showed rapid formation of oil aggregates that were similar in size and appearance compared to oil aggregates observed in surface waters near the spill site. Oil aggregates that formed in roller bottles were densely colonized by heterotrophic bacteria, exhibiting high rates of enzymatic activity (lipase hydrolysis indicative of oil degradation. Ambient waters surrounding aggregates also showed enhanced microbial activities not directly associated with primary oil-degradation (β-glucosidase; peptidase, as well as a twofold increase in DOC. Concurrent changes in fluorescence properties of colored dissolved organic matter (CDOM suggest an increase in oil-derived, aromatic hydrocarbons in the DOC pool. Thus our data indicate that oil aggregates mediate, by two distinct mechanisms, the transfer of hydrocarbons to the deep sea: a microbially-derived flux of oil-derived DOC from sinking oil aggregates into the ambient water column, and rapid sedimentation of the oil aggregates themselves, serving as vehicles for oily particulate matter as well as oil aggregate-associated microbial communities.

  13. Evaluating bacterial community structures in oil collected from the sea surface and sediment in the northern Gulf of Mexico after the Deepwater Horizon oil spill

    OpenAIRE

    Liu, Zhanfei; Liu, Jiqing

    2013-01-01

    Bacterial community structures were evaluated in oil samples using culture-independent pyrosequencing, including oil mousses collected on sea surface and salt marshes during the Deepwater Horizon oil spill, and oil deposited in sediments adjacent to the wellhead 1 year after the spill. Phylogenetic analysis suggested that Erythrobacter, Rhodovulum, Stappia, and Thalassospira of Alphaproteobacteria were the prevailing groups in the oil mousses, which may relate to high temperatures and strong ...

  14. LCA and economic evaluation of landfill leachate and gas technologies.

    Science.gov (United States)

    Damgaard, Anders; Manfredi, Simone; Merrild, Hanna; Stensøe, Steen; Christensen, Thomas H

    2011-07-01

    Landfills receiving a mix of waste, including organics, have developed dramatically over the last 3-4 decades; from open dumps to engineered facilities with extensive controls on leachate and gas. The conventional municipal landfill will in most climates produce a highly contaminated leachate and a significant amount of landfill gas. Leachate controls may include bottom liners and leachate collection systems as well as leachate treatment prior to discharge to surface water. Gas controls may include oxidizing top covers, gas collection systems with flares or gas utilization systems for production of electricity and heat. The importance of leachate and gas control measures in reducing the overall environmental impact from a conventional landfill was assessed by life-cycle-assessment (LCA). The direct cost for the measures were also estimated providing a basis for assessing which measures are the most cost-effective in reducing the impact from a conventional landfill. This was done by modeling landfills ranging from a simple open dump to highly engineered conventional landfills with energy recovery in form of heat or electricity. The modeling was done in the waste LCA model EASEWASTE. The results showed drastic improvements for most impact categories. Global warming went from an impact of 0.1 person equivalent (PE) for the dump to -0.05 PE for the best design. Similar improvements were found for photochemical ozone formation (0.02 PE to 0.002 PE) and stratospheric ozone formation (0.04 PE to 0.001 PE). For the toxic and spoiled groundwater impact categories the trend is not as clear. The reason for this was that the load to the environment shifted as more technologies were used. For the dump landfill the main impacts were impacts for spoiled groundwater due to lack of leachate collection, 2.3 PE down to 0.4 PE when leachate is collected. However, at the same time, leachate collection causes a slight increase in eco-toxicity and human toxicity via water (0.007 E to 0

  15. Environmental isotopes and major ions for tracing leachate contamination from a municipal landfill in Metro Manila, Philippines

    International Nuclear Information System (INIS)

    Castañeda, S.S.; Sucgang, R.J.; Almoneda, R.V.; Mendoza, N.D.S.; David, C.P.C.

    2012-01-01

    The surface water and groundwater sources in the vicinity of a major municipal landfill in Metro Manila, Philippines were investigated to determine contamination by landfill leachate. Tritium, stable isotopes of hydrogen and oxygen, and major ions in the leachate and freshwater within the landfill environment were determined. The leachate contained elevated tritium activities and high concentrations of sodium, chloride, potassium, and calcium. The concentrations of tritium and the leachate related ions in the affected surface water were significantly higher than the non-impacted water and correlated strongly with distance from the leachate source, following a negative exponential relationship, providing evidence of leachate transport along the affected surface water. Enrichment in deuterium was exhibited by leachate in the holding pond but not by the effluent leachate. The stable isotope signature of leachate is masked in the surface water due to dilution by stream water. Dilution similarly masked the effect of leachate in the shallow groundwater which was strongly influenced by precipitation. Evidence of leachate contamination in the deep groundwater was sporadic. In isolated cases, elevated tritium concentrations coincided with enrichment in deuterium. In the same case, leachate related ions, Na, Ca, Mg, and Cl, varied with rainfall but generally increased from 2003 to 2009. The effect on the groundwater of methane produced within the landfill was seen in the depletion in deuterium in groundwater in the drier months. - Highlights: ► Environmental isotopes and major ions as tracers of landfill leachate contamination. ► Tritium and major ions unequivocally show leachate transport in surface water. ► Groundwater enriched in deuterium and tritium attributed to leachate contamination.

  16. Sombric horizon: five decades without evolution

    Directory of Open Access Journals (Sweden)

    Jaime Antonio de Almeida

    2015-02-01

    Full Text Available The sombric horizon is a diagnostic subsurface horizon defined in the soil classification system of the United States (Soil Taxonomy and FAO (WRB, used to classify the soil at different categorical levels. The sombric horizon has a soil color darker than the overlying surface(s horizon(s, and must show illuvial humus accumulation features, though they are not associated with aluminum (Al, as in the spodic horizon, nor associated with sodium (Na, as in the natric horizon. There are also criteria to distinguish it from buried A horizons. However, since the first references and proposed concept of the sombric horizon in African soils made by Sys and co-workers in the 1960s, and adopted by the Soil Taxonomy edition of 1975, few modifications have been made to its definition. Moreover, the pedogenic process involved in illuvial humus accumulation in these horizons remains inadequately clarified, making the distinction between the sombric and spodic or buried A horizon difficult and unclear. This review reports the historical evolution of the sombric horizon concept, its definition and inconsistencies under different soil classification systems, and the current hypothesis, together with its fragilities, proposed to explain the soil illuvial humus accumulation. Although it is recognized that further research is necessary, alternative criteria are proposed for the definition of the sombric horizon in the Brazilian System of Soil Classification.

  17. Tracing solid waste leachate in groundwater by 13C

    Science.gov (United States)

    Haarstad, Ketil; Bloem, Esther; Mæhlum, Trond

    2010-05-01

    Tracers should be used to monitor emissions of leachate from landfills, in order to evaluate environmental pollution. We investigated a selection of parameters commonly found in leachate, in addition to isotopic and radioactive tracers, and their efficiency in tracing leachate in the environment, with emphasis on ground water. A detailed study at 6 locations focused on the occurrence of the isotopes 13C and 3H in leachate, surface and ground water, and comparing this to the water balance at the sites. The content of heavy carbon (13C) in leachate varied between 5.5 to 25.5, in ground water between 4.7 (when polluted), and -11.8 (when unpolluted) to -24.2, and in surface water from -13.1 to -19.7. Measurements of tritium did not show any systematic trend in the leachate and ground water samples. A comparison of the concentrations of tracer compounds, in addition to the radioactive tracers 3H and 13C showed that the latter seems to be the most stable and the factor correlating best with the hydraulic estimates.

  18. Effect of landfill characteristics on leachate organic matter properties and coagulation treatability.

    Science.gov (United States)

    Comstock, Sarah E H; Boyer, Treavor H; Graf, Katherine C; Townsend, Timothy G

    2010-11-01

    This work spans landfill characteristics, leachate organic matter properties, and coagulation chemistry to provide new insights into the physical-chemical treatability of stabilized landfill leachate. Furthermore, leachate organic matter is viewed in terms of dissolved organic matter (DOM) present in the natural environment, and coagulation chemistry is evaluated based on previous leachate and water treatment coagulation studies. Stabilized leachate was collected from four landfills for a total of seven leachate samples, and samples were coagulated using ferric chloride, ferric sulfate, and aluminum sulfate. Landfill characteristics, such as age, leachate recirculation, and cover material, influenced properties of DOM present in the leachate, as measured by specific ultraviolet (UV) absorbance at 254 nm (SUVA254) and fluorescence excitation-emission matrices. The coagulation performance of the metal salts was ferric sulfate>aluminum sulfate>ferric chloride, and DOM removal followed the trend of color>UV254>dissolved organic carbon>chemical oxygen demand (COD). Finally, a strong association was found between increasing SUVA254 and increasing DOM removal for coagulation of both leachate and natural surface water. Thus, SUVA254 is expected to be a better predictor of leachate treatability, in particular DOM removal, than the traditionally used ratio of biochemical oxygen demand to COD. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Present and long-term composition of MSW landfill leachate: A review

    DEFF Research Database (Denmark)

    Kjeldsen, Peter; Barlaz, M.A.; Rooker, A.P.

    2002-01-01

    The major potential environmental impacts related to landfill leachate are pollution of groundwater and surface waters. Landfill leachate contains pollutants that can be categorized into four groups (dissolved organic matter, inorganic macrocomponents, heavy metals, and xenobiotic organic compounds...... are observed. In contrast, the concentration of ammonia does not decrease, and often constitutes a major long-term pollutant in leachate. A broad range of xenobiotic organic compounds is observed in landfill leachate. The long-term behavior of landfills with respect to changes in oxidation-reduction status...

  20. Biological Treatment of Leachate using Sequencing Batch Reactor

    Directory of Open Access Journals (Sweden)

    WDMC Perera

    2014-12-01

    Full Text Available Normal 0 false false false EN-US X-NONE TA Abstract   In Sri Lanka municipal solid waste is generally disposed in poorly managed open dumps which lack liner systems and leachate collection systems. Rain water percolates through the waste layers to produce leachate which drains in to ground water and finally to nearby water bodies, degrading the quality of water. Leachate thus has become a major environmental concern in municipal waste management and treatment of leachate is a major challenge for the existing and proposed landfill sites.   The study was conducted to assess the feasibility of the usage of the Sequencing Batch Reactor in the treatment of the landfill leachate up to the proposed levels in the draft report of “Proposed Sri Lankan standard for landfill leachate to be disposed to the inland waters". Leachate collected from the open dumpsite at Meethotamulla, Western Province, Sri Lanka was used for leachate characterization.   SBR was constructed with a 10-liter working volume operated in an 18 hour cycle mode and each cycle consists of 15hours of aerobic, 2h settle and 0.5 h of fill/decant stages. The Dissolved Oxygen level within the SBR was maintained at 2 mg/l through the aerobic stage. Infeed was diluted with water during the acclimatization period and a leachate to water ratio of 55:45 was maintained. The removal efficiencies for different parameters were; COD (90.5%, BOD (92.6%, TS (92.1%, Conductivity (83.9%, Alkalinity (97.4%, Hardness (82.2%, Mg (80.5%, Fe (94.2%, Zn (63.4%, Cr (31.69%, Pb (99.6%, Sulphate (98.9%, and Phosphorus (71.4% respectively. In addition Ni and Cd were removed completely during a single SBR cycle. Thus the dilution of leachate in the dumpsites using municipal wastewater, groundwater or rainwater was identified as the most cost effective dilution methods. The effluent from the Sequencing batch reactor is proposed to be further treated using a constructed wetland before releasing to surface water.

  1. Polyfluoroalkyl compounds in landfill leachates

    International Nuclear Information System (INIS)

    Busch, Jan; Ahrens, Lutz; Sturm, Renate; Ebinghaus, Ralf

    2010-01-01

    Polyfluoroalkyl compounds (PFCs) are widely used in industry and consumer products. These products could end up finally in landfills where their leachates are a potential source for PFCs into the aqueous environment. In this study, samples of untreated and treated leachate from 22 landfill sites in Germany were analysed for 43 PFCs. ΣPFC concentrations ranged from 31 to 12,819 ng/L in untreated leachate and 4-8060 ng/L in treated leachate. The dominating compounds in untreated leachate were perfluorobutanoic acid (PFBA) (mean contribution 27%) and perfluorobutane sulfonate (PFBS) (24%). The discharge of PFCs into the aqueous environment depended on the cleaning treatment systems. Membrane treatments (reverse osmosis and nanofiltrations) and activated carbon released lower concentrations of PFCs into the environment than cleaning systems using wet air oxidation or only biological treatment. The mass flows of ΣPFCs into the aqueous environment ranged between 0.08 and 956 mg/day. - The first comprehensive survey of polyfluoroalkyl compounds (PFCs) in landfill leachates.

  2. Geophysical mapping of contaminant leachate around a reclaimed open dumpsite

    Directory of Open Access Journals (Sweden)

    W.O. Raji

    2017-07-01

    Full Text Available Very low frequency electromagnetic (VLF-EM, 2D Electrical Resistivity Profiling (2D ERP and Vertical Electrical Sounding (VES methods of geophysics were deployed to map the extent of leachate contamination in near-surface rocks around a popular reclaimed dumpsite in north central Nigeria. Two years after abandon and waste excavation; the dumpsite was converted to a residential area with over 80 houses under construction. Prior to waste dumping operation, clay-seal was installed at 2 m depth around the dumpsite to prevent leachate from the waste material flowing to the adjoining area. Results from VLF, 2D ERP, and VES show presence of leachate contamination in rocks and soil of the reclaimed dumpsite. Leachate has spread laterally up to a distance of about 1 km on the northern and southern parts of the dumpsite centre, and up to a depth of about 20 m. Compared to the results of similar survey in an area outside the dumpsite, leachate infiltration raised the conductivity signature of the rocks around the dumpsite by about 200%: from 7% to 22%. Both VLF-EM and 2D ERP show the presence of approximate north – south oriented structures/fracture characterised by high conductivity. VES results show the presence of four – five geo-electric layers. Important conclusions from the study are that (i leachate is still present in the rocks and soil of the reclaimed dumpsite two years after the abandonment and excavation of the waste materials, and (ii the clay seal installed around the dumpsite could not prevent leachate migration to the adjoining areas.

  3. Parametric Analysis of Leachate and Water Resources around Municipal Solid Waste Landfill area in Solan

    Directory of Open Access Journals (Sweden)

    Sharma Deepika

    2016-01-01

    Full Text Available Leachate is defined as the liquid that drains from the landfill. The paper presents the physico-chemical, bacteriological and heavy metal testing results carried out for leachate, surface and sub-surface water samples collected from municipal solid waste landfill and different water sources in Solan to find out the effect of leachate percolation on groundwater quality. Physico-chemical parameters analysed were, pH, Total Dissolve Solid (TDS, sulphate, turbidity, Electrical Conductivity (EC while biological parameters tested were Biological Oxygen Demand (BOD, Chemical Oxygen Demand (COD, Most Probable Number (MPN test and ammonical nitrogen. Testing for heavy metals (Pb, Zn, Cr, Ni, Fe were carried out and have been reported. The results reveal that the leachate from the unlined landfill may have a significant impact on the groundwater resource (often used as drinking source particularly because of the toxic nature of the leachate coupled with the soil characteristics which is permeable in nature.

  4. Coal pile leachate treatment

    Energy Technology Data Exchange (ETDEWEB)

    Davis, E C; Kimmitt, R R

    1982-09-01

    The steam plant located at the Oak Ridge National Laboratory was converted from oil- to coal-fired boilers. In the process, a diked, 1.6-ha coal storage yard was constructed. The purpose of this report is to describe the treatment system designed to neutralize the estimated 18,000 m/sup 3/ of acidic runoff that will be produced each year. A literature review and laboratory treatability study were conducted which identified two treatment systems that will be employed to neutralize the acidic runoff. The first, a manually operated system, will be constructed at a cost of $200,000 and will operate for an interim period of four years. This system will provide for leachate neutralization until a more automated system can be brought on-line. The second, a fully automated system, is described and will be constructed at an estimated cost of $650,000. This automated runoff treatment system will ensure that drainage from the storage yard meets current National Pollutant Discharge Elimination System Standards for pH and total suspended solids, as well as future standards, which are likely to include several metals along with selected trace elements.

  5. Treatment Horizon

    Science.gov (United States)

    ... research; not available to the public.) The 5-HT2A receptor is found on the surface of many ... Molecules of the neurotransmitter serotonin fit into 5-HT2A receptors like a key fitting into a lock. ...

  6. New Horizons at Pluto

    Science.gov (United States)

    2007-01-01

    Artist's concept of the New Horizons spacecraft as it approaches Pluto and its largest moon, Charon, in July 2015. The craft's miniature cameras, radio science experiment, ultraviolet and infrared spectrometers and space plasma experiments will characterize the global geology and geomorphology of Pluto and Charon, map their surface compositions and temperatures, and examine Pluto's atmosphere in detail. The spacecraft's most prominent design feature is a nearly 7-foot (2.1-meter) dish antenna, through which it will communicate with Earth from as far as 4.7 billion miles (7.5 billion kilometers) away.

  7. LANDFILL LEACHATES PRETREATMENT BY OZONATION

    Directory of Open Access Journals (Sweden)

    Jacek Leszczyński

    2016-06-01

    Full Text Available In this paper, the application of ozonation processes for stabilized landfill leachate treatment was investigated. The leachate came from a municipal sanitary landfill located nearby Bielsk Podlaski. The average values of its main parameters were: pH 8.23; COD 870 mgO2/dm3; BOD 90 mgO2/dm3; NH4+ 136.2 mgN/dm3; UV254 absorbance 0.312 and turbidity 14 NTU. The ozone dosages used were in the range of 115.5 to 808.5 mgO3/dm3 of the leachate. The maximum COD, color and UV254 absorbance removal wa.5 mgO3/dm3. After oxidation, the ratio of BOD/COD was increased from 0.1 up to 0.23.

  8. Biogeochemistry of landfill leachate plumes

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Kjeldsen, Peter; Bjerg, Poul Løgstrup

    2001-01-01

    is on dissolved organic matter, xenobiotic organic compounds, inorganic macrocomponents as anions and cations, and heavy metals. Laboratory as well as field investigations are included. This review is an up-date of an earlier comprehensive review. The review shows that most leachate contamination plumes...... are relatively narrow and do not in terms of width exceed the width of the landfill. The concept of redox zones being present in the plume has been confirmed by the reported composition of the leachate contaminated groundwater at several landfills and constitutes an important framework for understanding...... in a few cases. Apparently, observations in actual plumes indicate more extensive degradation than has been documented in the laboratory. The behavior of cations in leachate plumes is strongly influenced by exchange with the sediment, although the sediment often is very coarse and sandy. Ammonium seems...

  9. Predicted Antenna Temperatures Measured by REX/New Horizons During The Pluto’s FlybyProbing the sub-surface in Microwave

    Science.gov (United States)

    Leyrat, Cedric; Le Gall, Alice; Lorenz, Ralph; Boomi, Shadi

    2017-10-01

    The Pluto dwarf planet was observed in details in July 2015 by the New Horizons spacecraft (NASA) during a close-targeted flyby which reavealed surprising and fascinating landscapes with a variety of albedo and chemical composition over the surface. During the flyby, the REX microwave instrument was activated in order to measure the antenna temperature while the beam crossed Pluto’s surface. In particular, 3 scans were performed, the first two during few tens of seconds when both the day and night side of Pluto were observed, including the South pole ; and the last one during an occultation with Earth. We present here predited antenna temperatures considering the known and assumed variations of thermal and electrical properties of the Pluto’s sub-surface.. Each scan allow to observe thermal radiation at 4.2 cm wavelength of the surface and subsurface of Pluto, at different locations (latitudes / longitudes). Using a seasonnal thermal model that considers the measured Bond albedo and type of ice, we have modeled the Brightness temperatures that were measured by REX, for different amount of porosity (or thermal inertia). This modeling uses a seasonally-forced thermal model and an emissivity model in the case of circular polarized observations. An antenna temperature if then retrieved assuming a beam pattern for REX. We present here how the antenna temperatures vary with the porosity of the ices obseved.

  10. Electrodynamics of the event horizon

    International Nuclear Information System (INIS)

    Punsly, B.; Coroniti, F.V.

    1989-01-01

    This paper is an investigation of the electrodynamics of the event horizon of a Kerr black hole. It is demonstrated that the event horizon behaves quite generally as an asymptotic vacuum infinity for axisymmetric, charge-neutral, accreting electromagnetic sources. This is in contrast with the general notion that the event horizon can be treated as an imperfect conductive membrane with a surface impedance of 4π/c. The conductive-membrane model has been incorporated into the more sophisticated membrane paradigm of Thorne, Price, and Macdonald by supplementing the model with the full equations of general relativity. In certain situations (in particular those of astrophysical interest), the conductive-membrane interpretation forms the appropriate set of pictures and images in the membrane paradigm. In this paper we reevaluate the specific gedanken experiments that were originally used to motivate the paradigm. We find that great care must be exercised if the detailed interaction of a black hole's external gravitational field with a magnetized plasma is modeled by the electrodynamics of the conductive horizon membrane. For ingoing flows of plasma or electromagnetic waves (when the hole is passively accepting information), the interpretation of the horizon as a vacuum infinity is equivalent to an imperfect conductor with a surface impedance of 4π/c (the impedance of the vacuum). In situations when an imperfect conductor should radiate information (such as a Faraday wheel) the event horizon cannot, since it is an infinity. The event horizon does not behave quite generally as an imperfect conductor, but has electrodynamic properties unique to itself

  11. Response of salt marshes to oiling from the Deepwater Horizon spill: Implications for plant growth, soil surface-erosion, and shoreline stability.

    Science.gov (United States)

    Lin, Qianxin; Mendelssohn, Irving A; Graham, Sean A; Hou, Aixin; Fleeger, John W; Deis, Donald R

    2016-07-01

    We investigated the initial impacts and post spill recovery of salt marshes over a 3.5-year period along northern Barataria Bay, LA, USA exposed to varying degrees of Deepwater Horizon oiling to determine the effects on shoreline-stabilizing vegetation and soil processes. In moderately oiled marshes, surface soil total petroleum hydrocarbon concentrations were ~70mgg(-1) nine months after the spill. Though initial impacts of moderate oiling were evident, Spartina alterniflora and Juncus roemerianus aboveground biomass and total live belowground biomass were equivalent to reference marshes within 24-30months post spill. In contrast, heavily oiled marsh plants did not fully recover from oiling with surface soil total petroleum hydrocarbon concentrations that exceeded 500mgg(-1) nine months after oiling. Initially, heavy oiling resulted in near complete plant mortality, and subsequent recovery of live aboveground biomass was only 50% of reference marshes 42months after the spill. Heavy oiling also changed the vegetation structure of shoreline marshes from a mixed Spartina-Juncus community to predominantly Spartina; live Spartina aboveground biomass recovered within 2-3years, however, Juncus showed no recovery. In addition, live belowground biomass (0-12cm) in heavily oiled marshes was reduced by 76% three and a half years after the spill. Detrimental effects of heavy oiling on marsh plants also corresponded with significantly lower soil shear strength, lower sedimentation rates, and higher vertical soil-surface erosion rates, thus potentially affecting shoreline salt marsh stability. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Organic matter composition at intact biopore and crack surfaces of Luvisol B-horizons analyzed by FTIR spectroscopy and Pyrolysis-Field Ionization Mass Spectrometry

    Science.gov (United States)

    Leue, Martin; Eckhardt, Kai-Uwe; Ellerbrock, Ruth H.; Gerke, Horst H.; Leinweber, Peter

    2015-04-01

    In the B-horizons of Luvisols, surfaces of biopores and aggregates can be enriched in clay and organic matter (OM), relative to the bulk of the soil matrix. The OM composition of these coatings determines their bio-physico-chemical properties and is relevant for transport and transformation processes but is largely unknown at the molecular scale. The objective of this study was an extended characterization of the OM composition at intact biopore and aggregate surfaces. Specifically, we aimed to improve the interpretation of data obtained with Fourier transform infrared spectroscopy in diffuse reflectance mode (DRIFT) by combining the signals from DRIFT spectra with data from pyrolysis-field ionization mass spectrometry (Py-FIMS) as a more detailed molecular-scale analysis. Samples were manually separated from the outermost surfaces of earthworm burrows, coated and uncoated cracks, root channels, and pinhole fillings of the B-horizons of Luvisols developed from loess and glacial till. The OM at earthworm burrow walls was characterized by a mix of chemically labile aliphatic C-rich and more stable lignin and alkylaromatic compounds whereas the OM of coated cracks and pinholes was dominated by relatively stable heterocylic N and nitriles, and high-molecular aromatic compounds (benzonitrile and naphthalene). This more recalcitrant OM likely originated from the combustion of biomass and, in case of the till-derived Luvisol, from diesel exhausts. The OM composition of pore walls reflected the differences between biopores (i.e., topsoil and plant residual, worm activity) and cracks (i.e., solutes and colloids, rapid percolation). The information of Py-FI mass spectra enabled the assignment of OM functional groups also from spectral regions of overlapping DRIFT signal intensities to specific OM compound classes. In particular, bands from C=O and C=C bonds in the infrared range of wave number 1688 … 1565 cm-1 were related to highly stable, chemically recalcitrant OM

  13. Treating leachate by Fenton oxidation

    Directory of Open Access Journals (Sweden)

    Roger Iván Méndez Novelo

    2010-01-01

    Full Text Available Leachates are formed from liquids, mainly rainwater, percolating through solid wastes during stabilisation. Their composition is variable and highly toxic; leachate treatment is therefore a complex task. Leachates represent a high risk to health due to the Yucatan Peninsula’s highly permeable soil. The results are presented from applying the Fenton process to treating leachate from the sanitary Merida landfill, Yucatan, Mexico. The Fenton process consists of treating the contaminant load with an H2O2 and FeSO4 combination in acidic conditions. Optimal reaction time, pH value, Fenton reagent dose, post treatment coagulation – flocculation doses and increased biodegradability index were all determined. Optimal oxidation conditions and doses were 202+ minute contact time, 4 pH, 600 mg/L H2O2 concentration and 1,000 mg/L Fe. Average organic matter removal rate, measured as CODS and TOC, were 78% and 87% respectively. The biodegradability index increased from 0.07 to 0.11 during the Fenton process and up to 0.13 when the Fenton process was followed by coagulation-flocculation.

  14. Parameter estimation of a two-horizon soil profile by combining crop canopy and surface soil moisture observations using GLUE

    Science.gov (United States)

    Sreelash, K.; Sekhar, M.; Ruiz, L.; Tomer, S. K.; Guérif, M.; Buis, S.; Durand, P.; Gascuel-Odoux, C.

    2012-08-01

    SummaryEstimation of soil parameters by inverse modeling using observations on either surface soil moisture or crop variables has been successfully attempted in many studies, but difficulties to estimate root zone properties arise when heterogeneous layered soils are considered. The objective of this study was to explore the potential of combining observations on surface soil moisture and crop variables - leaf area index (LAI) and above-ground biomass for estimating soil parameters (water holding capacity and soil depth) in a two-layered soil system using inversion of the crop model STICS. This was performed using GLUE method on a synthetic data set on varying soil types and on a data set from a field experiment carried out in two maize plots in South India. The main results were (i) combination of surface soil moisture and above-ground biomass provided consistently good estimates with small uncertainity of soil properties for the two soil layers, for a wide range of soil paramater values, both in the synthetic and the field experiment, (ii) above-ground biomass was found to give relatively better estimates and lower uncertainty than LAI when combined with surface soil moisture, especially for estimation of soil depth, (iii) surface soil moisture data, either alone or combined with crop variables, provided a very good estimate of the water holding capacity of the upper soil layer with very small uncertainty whereas using the surface soil moisture alone gave very poor estimates of the soil properties of the deeper layer, and (iv) using crop variables alone (else above-ground biomass or LAI) provided reasonable estimates of the deeper layer properties depending on the soil type but provided poor estimates of the first layer properties. The robustness of combining observations of the surface soil moisture and the above-ground biomass for estimating two layer soil properties, which was demonstrated using both synthetic and field experiments in this study, needs now to

  15. Evaluating bacterial community structures in oil collected from the sea surface and sediment in the northern Gulf of Mexico after the Deepwater Horizon oil spill.

    Science.gov (United States)

    Liu, Zhanfei; Liu, Jiqing

    2013-06-01

    Bacterial community structures were evaluated in oil samples using culture-independent pyrosequencing, including oil mousses collected on sea surface and salt marshes during the Deepwater Horizon oil spill, and oil deposited in sediments adjacent to the wellhead 1 year after the spill. Phylogenetic analysis suggested that Erythrobacter, Rhodovulum, Stappia, and Thalassospira of Alphaproteobacteria were the prevailing groups in the oil mousses, which may relate to high temperatures and strong irradiance in surface Gulf waters. In the mousse collected from the leaves of Spartina alterniflora, Vibrio of Gammaproteobacteria represented 57% of the total operational taxonomic units, suggesting that this indigenous genus is particularly responsive to the oil contamination in salt marshes. The bacterial communities in oil-contaminated sediments were highly diversified. The relatively high abundance of the Methylococcus, Methylobacter, Actinobacteria, Firmicutes, and Chlorofexi bacteria resembles those found in certain cold-seep sediments with gas hydrates. Bacterial communities in the overlying water of the oil-contaminated sediment were dominated by Ralstonia of Betaproteobacteria, which can degrade small aromatics, and Saccharophagus degradans of Gammaproteobacteria, a cellulose degrader, suggesting that overlying water was affected by the oil-contaminated sediments, possibly due to the dissolution of small aromatics and biosurfactants produced during biodegradation. Overall, these results provided key information needed to evaluate oil degradation in the region and develop future bioremediation strategies. © 2013 The Authors. Microbiology Open published by John Wiley & Sons Ltd.

  16. Leachates draining from controlled municipal solid waste landfill: Detailed geochemical characterization and toxicity tests.

    Science.gov (United States)

    Mavakala, Bienvenu K; Le Faucheur, Séverine; Mulaji, Crispin K; Laffite, Amandine; Devarajan, Naresh; Biey, Emmanuel M; Giuliani, Gregory; Otamonga, Jean-Paul; Kabatusuila, Prosper; Mpiana, Pius T; Poté, John

    2016-09-01

    Management of municipal solid wastes in many countries consists of waste disposal into landfill without treatment or selective collection of solid waste fractions including plastics, paper, glass, metals, electronic waste, and organic fraction leading to the unsolved problem of contamination of numerous ecosystems such as air, soil, surface, and ground water. Knowledge of leachate composition is critical in risk assessment of long-term impact of landfills on human health and the environment as well as for prevention of negative outcomes. The research presented in this paper investigates the seasonal variation of draining leachate composition and resulting toxicity as well as the contamination status of soil/sediment from lagoon basins receiving leachates from landfill in Mpasa, a suburb of Kinshasa in the Democratic Republic of the Congo. Samples were collected during the dry and rainy seasons and analyzed for pH, electrical conductivity, dissolved oxygen, soluble ions, toxic metals, and were then subjected to toxicity tests. Results highlight the significant seasonal difference in leachate physicochemical composition. Affected soil/sediment showed higher values for toxic metals than leachates, indicating the possibility of using lagoon system for the purification of landfill leachates, especially for organic matter and heavy metal sedimentation. However, the ecotoxicity tests demonstrated that leachates are still a significant source of toxicity for terrestrial and benthic organisms. Therefore, landfill leachates should not be discarded into the environment (soil or surface water) without prior treatment. Interest in the use of macrophytes in lagoon system is growing and toxic metal retention in lagoon basin receiving systems needs to be fully investigated in the future. This study presents useful tools for evaluating landfill leachate quality and risk in lagoon systems which can be applied to similar environmental compartments. Copyright © 2016 Elsevier Ltd. All

  17. What happens to the horizon when a black hole radiates

    International Nuclear Information System (INIS)

    York, J.W. Jr.

    1984-01-01

    The paper concerns a detailed study of the changes the horizon undergoes when a black hole emits energy. Horizons; evaporating metric; quantum ergosphere; proper acceleration and local temperature of the apparent horizon; Raychadhuri equation, surface gravity and mass; black holes and white holes; high temperature extrapolation; and low temperature limit; are all discussed. (U.K.)

  18. Cadmium complexation by solid waste leachates

    DEFF Research Database (Denmark)

    Xu Ze Lun; Christensen, Thomas H.

    1989-01-01

    A previously reported method for determination of Cd species in solid waste leachates has been applied to ten leachate samples representing five different types of solid waste: refuse compost, flyash from coal combustion, sewage sludge, refuse incineration residues and landfilled municipal waste......, slowly labile complexes and stable complexes. Leachates originating from the same type of solid waste showed different fractions of Cd, in particular with respect to free divalent Cd and stable Cd complexes. Only coal flyash showed almost identical fractions of Cd in the two leachates. The latter is due...

  19. Molecular Investigation of the Short-term Sequestration of Natural Abundance 13C -labelled Cow Dung in the Surface Horizons of a Temperate Grassland Soil

    Science.gov (United States)

    Dungait, J.; Bol, R.; Evershed, R. P.

    2004-12-01

    An adequate understanding of the carbon (C) sequestration potential of grasslands requires that the quantity and residence times of C inputs be measured. Herbivore dung is largely comprised of plant cell wall material, a significant source of stable C in intensively grazed temperate grassland ecosystems that contributes to the soil carbon budget. Our work uses compound-specific isotope analysis to identify the pattern of input of dung-derived compounds from natural abundance 13C/-labelled cow dung into the surface horizons of a temperate grassland soil over one year. C4 dung (δ 13C \\-12.6 ‰ ) from maize fed cows was applied to a temperate grassland surface (δ 13C \\-29.95 ‰ ) at IGER-North Wyke (Devon, UK), and dung remains and soil cores beneath the treatments collected at ŧ = 7, 14, 28, 56, 112, 224 and 372 days. Bulk dung carbon present in the 0\\-1 cm and 1\\-5 cm surface horizons of a grassland soil over one year was estimated using Δ 13C between C4 dung and C3 dung, after Bol {\\et al.} (2000). The major biochemical components of dung were quantified using proximate forage fibre analyses, after Goering and Van Soest (1970) and identified using `wet' chemical and GC-MS methods. Plant cell wall polysaccharides and lignin were found to account for up to 67 {%} of dung dry matter. Hydrolysed polysaccharides were prepared as alditol acetates for analyses (after Docherty {\\et al.}, 2001), and a novel application of an off-line pyrolysis method applied to measure lignin-derived phenolic compounds (after Poole & van Bergen, 2002). This paper focuses on major events in the incorporation of dung carbon, estimated using natural abundance 13C&-slash;labelling technique. This revealed a major bulk input of dung carbon after a period of significant rainfall with a consequent decline in bulk soil δ 13C values until the end of the experiment (Dungait {\\et al.}, submitted). Findings will be presented revealing contribution of plant cell wall polysaccharides and

  20. Examples of plasma horizons

    International Nuclear Information System (INIS)

    Hanni, R.S.

    1975-01-01

    The concept of the plasma horizon, defined as the boundary of the region in which an infinitely thin plasma can be supported against Coulomb attraction by a magnetic field, shows that the argument of selective accretion does not rule out the existence of charged black holes embedded in a conducting plasma. A detailed account of the covariant definition of plasma horizon is given and some examples of plasma horizons are presented. 7 references

  1. Comparison of bacterial communities in leachate from decomposing bovine carcasses

    Directory of Open Access Journals (Sweden)

    Seung Hak Yang

    2017-11-01

    Full Text Available Objective Burial is associated with environmental effects such as the contamination of ground or surface water with biological materials generated during the decomposition process. Therefore, bacterial communities in leachates originating from the decomposing bovine carcasses were investigated. Methods To understand the process of bovine (Hanwoo carcass decomposition, we simulated burial using a lab-scale reactor with a volume of 5.15 m3. Leachate samples from 3 carcasses were collected using a peristaltic pump once a month for a period of 5 months, and bacterial communities in samples were identified by pyrosequencing of the 16S rRNA gene. Results We obtained a total of 110,442 reads from the triplicate samples of various sampling time points (total of 15 samples, and found that the phylum Firmicutes was dominant at most sampling times. Differences in the bacterial communities at the various time points were observed among the triplicate samples. The bacterial communities sampled at 4 months showed the most different compositions. The genera Pseudomonas and Psychrobacter in the phylum Proteobacteria were dominant in all of the samples obtained after 3 months. Bacillaceae, Clostridium, and Clostridiales were found to be predominant after 4 months in the leachate from one carcass, whereas Planococcaceae was found to be a dominant in samples obtained at the first and second months from the other two carcasses. The results showed that potentially pathogenic microbes such as Clostridium derived from bovine leachate could dominate the soil environment of a burial site. Conclusion Our results indicated that the composition of bacterial communities in leachates of a decomposing bovine shifted continuously during the experimental period, with significant changes detected after 4 months of burial.

  2. Gribov's ambiguities and horizons

    International Nuclear Information System (INIS)

    de Vega, H.J.

    1979-01-01

    Gribov's ambiguities prevent a formulation of a gauge theory on the whole space of field configurations. We introduce the concept of horizon around some field A 0 as the nearest field to it exhibiting gauge ambiguities. The constrained equations determining the horizon are explicitly given. These concepts are applied to the gauge problems associated with collective coordinates. For a two-dimensional model, horizon solutions around one soliton are found for a whole family of gauges and its properties are analyzed. By varying the gauge condition we show that the ''optimal horizon,'' the one which surrounds the largest portion of functional space, lies at the threshold of soliton-antisoliton production

  3. Ocorrência de corpos silicosos em horizontes superficiais de solos de diferentes ecossistemas Occurrence of silica bodies in surface horizons of soils in different ecosystems

    Directory of Open Access Journals (Sweden)

    Liovando Marciano da Costa

    2010-06-01

    Full Text Available O entendimento dos processos que causam as diferentes distribuições de corpos silicosos no solo é essencial para a interpretação dos possíveis fatores ambientais responsáveis pela estabilidade deles, deposição de sedimentos, formação de paleossolos e para análise de sítios arqueológicos. Assim, a presente pesquisa objetivou identificar a ocorrência de corpos silicosos encontrados em horizontes superficiais de solos oriundos de diferentes ecossistemas terrestres. Amostras de horizonte superficial de 10 perfis de solo foram coletadas e queimadas em mufla, para remoção da matéria orgânica. Posteriormente, as amostras foram tratadas com HCl 10 cL L-1, para remoção das impurezas contidas na cinza. A fração silte foi obtida por sedimentação, usando o procedimento de análise granulométrica. A maior parte dos corpos silicosos em solos encontra-se na fração silte. Dessa fração, montaram-se lâminas, utilizando óleo de imersão tipo A para identificação dos corpos silicosos em microscópio óptico. A análise dos resultados permitiu observar a variedade de formas e abundância de corpos silicosos nos solos estudados, sendo mais abundantes e diversificados no solo desenvolvido de quartzito. Nos Latossolos, não houve diferença em abundância de fitólitos em relação aos solos dos biomas do Cerrado, Mata Atlântica e Caatinga.The understanding of the processes that cause the varied distribution of silica bodies in soils is essential for the interpretation of the possible environmental factors related to their stability, sediment deposition, paleosol formation and for the analysis of archaeological sites. Thus, this study had the objective of identifying and characterizing the silica bodies morphology from surface soil horizons collected at different terrestrial ecosystems. Samples of surface horizons were collected from 10 soil profiles and heated in a muffle furnace to remove organic matter. Thereafter the samples were

  4. Fresh Kills leachate treatment and minimization study. Volume 1, Characteristics and treatment alternatives: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Fillos, J.; Khanbilvardi, R.

    1993-09-01

    The New York City Department of Sanitation is developing a comprehensive landfill leachate management plan for the Fresh Kills Landfill. The leachate was first analyzed for conventional and priority pollutants. The leachate was well buffered at pH 7 to 8 with an alkalinity of 5,000 to 6,000 mg/L. The BOD was low, usually less than 100 mg/L, but the COD was as high as 1,800 mg/L. Ammonia concentrations were around 700 mg/L and the color resembled strong tea at 3,000 colorimetric units. Only few of the priority pollutants were present, and at extremely low concentrations. Based on the chemical characteristics of the leachate, the primary environmental impact would be on the oxygen balance of the receiving surface waters.

  5. Cadmium complexation by solid waste leachates

    DEFF Research Database (Denmark)

    Xu Ze Lun; Christensen, Thomas H.

    1989-01-01

    A previously reported method for determination of Cd species in solid waste leachates has been applied to ten leachate samples representing five different types of solid waste: refuse compost, flyash from coal combustion, sewage sludge, refuse incineration residues and landfilled municipal waste....

  6. Two Horizons of Fusion

    Science.gov (United States)

    Lo, Mun Ling; Chik, Pakey Pui Man

    2016-01-01

    In this paper, we aim to differentiate the internal and external horizons of "fusion." "Fusion" in the internal horizon relates to the structure and meaning of the object of learning as experienced by the learner. It clarifies the interrelationships among an object's critical features and aspects. It also illuminates the…

  7. VMware horizon view essentials

    CERN Document Server

    von Oven, Peter

    2014-01-01

    If you are a desktop administrator or an end user of a computing project team looking to speed up to the latest VMware Horizon View solution, then this book is perfect for you. It is your ideal companion to deploy a solution to centrally manage and virtualize your desktop estate using Horizon View 6.0.

  8. Importance of lateral flux and its percolation depth on organic carbon export in Arctic tundra soil: Implications from a soil leaching experiment: Changes of OC in Arctic Soil Leachate

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiaowen [Department of Geological Sciences, University of Florida, Gainesville Florida USA; Hutchings, Jack A. [Department of Geological Sciences, University of Florida, Gainesville Florida USA; Bianchi, Thomas S. [Department of Geological Sciences, University of Florida, Gainesville Florida USA; Liu, Yina [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland Washington USA; Arellano, Ana R. [Department of Geological Sciences, University of Florida, Gainesville Florida USA; Schuur, Edward A. G. [Center for Ecosystem Science and Society and Department of Biological Sciences, Northern Arizona University, Flagstaff Arizona USA; Department of Biology, University of Florida, Gainesville Florida USA

    2017-04-01

    Temperature rise in the Arctic is causing deepening of active layers and resulting in the mobilization of deep permafrost dissolved organic matter (DOM). However, the mechanisms of DOM mobilization from Arctic soils, especially upper soil horizons which are drained most frequently through a year, are poorly understood. Here, we conducted a short-term leaching experiment on surface and deep organic active layer soils, from the Yukon River basin, to examine the effects of DOM transport on bulk and molecular characteristics. Our data showed a net release of DOM from surface soils equal to an average of 5% of soil carbon. Conversely, deep soils percolated with surface leachates retained up to 27% of bulk DOM-while releasing fluorescent components (up to 107%), indicating selective release of aromatic components (e.g. lignin, tannin), while retaining non-chromophoric components, as supported by spectrofluorometric and ultra high resolution mass spectroscopic techniques. Our findings highlight the importance of the lateral flux of DOM on ecosystem carbon balance as well as processing of DOM transport through organic active layer soils en route to rivers and streams. This work also suggests the potential role of leachate export as an important mechanism of C losses from Arctic soils, in comparison with the more traditional pathway from soil to atmosphere in a warming Arctic.

  9. Analysis of parameters for leachate treatment in a greenhouse system

    Directory of Open Access Journals (Sweden)

    Ana Laura Gómez Blasco

    2017-06-01

    Full Text Available In this paper is presented an approach for landfill leachate treatment using enhanced natural evaporation. Experimental set up considered using a greenhouse pilot prototype placed into the municipal landfill of Puebla city, México. The greenhouse was built with a basement surface enough to place 9 trays with leachate. Treatment follow up was done through the following parameters: air temperature inside and outside the greenhouse; leachate temperature at surface and middle liquid height. Results of the first set of experiments defined a minimal initial liquid height of 20% in respect to the tray height; the 2nd set allowed defining optimal evaporation rate conditions evaluated in respect of a tray placed outside, considered as reference of 100% efficiency (blank, obtained results showed that morning and night processes provided efficiencies up to 2 times the reference; otherwise, afternoon measurements showed similar temperature values inside and outside. In general collected data at winter season provided efficiencies between 82% and 147%, in periods of 24 h, it was observed that higher liquid reductions took place at North, and lower ones at the South positions. Based on these results it was proposed a 20 days experiment, using stagnant (E and recharge (R conditions referred to the blank (L, the R process showed greater efficiency (168% than the stagnant one (158%. Leachate chemical characterization indicates that pH is highly stable; while total solids, chemical oxygen demand, sulfate and chloride exhibit an increase in concentration reaching values of 1.2–2.5 times the initial concentration, phosphate was the only parameter exhibiting a decreasing trend ending with 40% of its initial concentration.

  10. Effect of leachate solutions from fly ash bottom ash on groundwater quality

    Energy Technology Data Exchange (ETDEWEB)

    Kopsick, D.A.; Angino, E.E.

    1981-12-01

    Leaching experiments on fly ash and bottom ash for Ca, Mg, Na, K, Fe, Mn, Zn, Cu and Pb indicated a potential for contamination of ground- and surface-water supplies. Due to the variability in chemical composition of coals, it is difficult to make generalizations concerning the chemistry of leachate solutions from the ashes of the coals. A decrease in concentration with time of leaching was observed for all elements, except for Ca which was released at a constant rate. Fly ash from a Missouri coal generated a leachate enriched in Pb, Zn, Cu, Fe, Mn and Cd, reflective of the high Pb-Zn mineralization present in the surrounding area. With a pH of 3.0 this ash has the greatest potential for groundwater contamination. Conversely, leachates from Wyoming fly and bottom ashes exhibited low trace-metal concentrations. These same solutions were high in K, Na, Ca and Mg, and also showed strong pozzolanic behaviour, which will reduce the leachability of these ashes. In most instances, fly and bottom ash from Kentucky and Illinois coals yielded leachates intermediate in elemental composition to leachates of Missouri and Wyoming coal ashes. Leaching experiments indicate that it is not valid to predict the chemistry of leachates from fly and bottom ash based solely on the chemical composition of the ash. (16 refs.)

  11. Deepwater Horizon - Baseline Dataset

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In 2010, the Deepwater Horizon oil spill occurred in the Gulf of Mexico and the Natural Resources Damage Assessment (NRDA) was initiated to determine the extent of...

  12. Characterization and flux of marine oil snow settling toward the seafloor in the northern Gulf of Mexico during the Deepwater Horizon incident: Evidence for input from surface oil and impact on shallow shelf sediments.

    Science.gov (United States)

    Stout, Scott A; German, Christopher R

    2017-11-03

    Sediment trap samples from the shelf edge area (400-450m water depth), 58km northeast of the failed Macondo well, were collected before, during and after the Deepwater Horizon oil spill. Detailed chemical analyses of particulates revealed that fluxes of spill-derived TPH (2356μg/m 2 /day), total PAH (5.4μg/m 2 /day), and hopane (0.89μg/m 2 /day) settling to the seafloor directly beneath the surface-plume were 19- to 44-times higher during the active spill than pre- and post-spill background values. The oil was variably biodegraded, evaporated and photo-oxidized indicating that it derived from the sinking of surface oil. The hopane-based oil flux that we calculate (10bbl/km 2 ) indicates that at least 76,000bbl of Macondo oil that reached the ocean surface subsequently sank over an area of approximately 7600km 2 . We explore how this flux of sunken surface oil contributed to the total volume of oil deposited on the seafloor following the Deepwater Horizon incident. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Characterization and treatment of municipal landfill leachates

    Energy Technology Data Exchange (ETDEWEB)

    Welander, Ulrika

    1998-03-01

    The efficiency of different leachate treatment methods for the removal of refractory organic compounds and ammonium-nitrogen was investigated. The methods evaluated were nitrification, denitrification, adsorption onto activated carbon, precipitation by ferric chloride or aluminum sulphate and oxidation by ozone or Fenton`s reagent. Furthermore, analyses were performed on leachates from municipal landfills of different kinds (a biocell deposit, a conventional mixed landfill containing household and industrial waste, and an ash deposit) in order to study the leachate composition in regard to various hydrophobic organic compounds as a function of the type of waste deposited. The results suggested that, in order to achieve a satisfactory removal of both ammonium-nitrogen and organic substances, the treatment of methanogenic leachates should be performed through a process combining biological and physical or chemical stages. When the biological treatment was not combined with a physical or a chemical process a COD removal of only 20-30% was achieved, whereas the toxicity of the leachate was significantly reduced. In contrast, a combination of nitrification and either adsorption onto activated carbon or oxidation using Fenton`s reagent resulted in a COD removal of about 80%, although certain specific organic compounds, such as phthalates, were unaffected by the treatment. A combination of nitrification, precipitation by ferric chloride and adsorption onto activated carbon removed 96% of the TOC. The analyses of leachates from municipal landfills of different types showed the leachate from the ash deposit to contain more C4-substituted phenols than the other leachates and to likewise contain alkanes, which the others did not 154 refs, 12 figs, 4 tabs

  14. Magnetic and Electrical Properties of Leachate

    Directory of Open Access Journals (Sweden)

    Kartika Kirana

    2011-11-01

    Full Text Available Heavy metals content as well as magnetic and electrical properties of leachate from Sarimukti, West Java were studied in an attempt to seek correlation between heavy metals content and magnetic/electrical properties. Such correlation is expected to open the way for the use of magnetic/electrical properties as proxy indicators for the concentration of heavy metals in the leachate. The number of leachate samples studied is 21; 15 were taken spatially at depth of 1 m while the remaining 6 samples were taken vertically at a particular point. Measurement results showed that the heavy metals content in the leachate has a smaller concentration, except for Fe. The correlation between magnetic susceptibility and heavy metals content was found to be not so significant. The best correlation coefficient between magnetic susceptibility with heavy metals in leachate was found in Zn. Correlation between electrical conductivity and heavy metal is also not so significant, except for Zn and Cd. The use of magnetic properties as proxy indicator for heavy metals content in leachate is plausible provided that the magnetic susceptibility exceeds certain threshold value. Correlation between magnetic susceptibility, electrical conductivity and heavy metal content would be good if each quantity has a large value.

  15. Transport of organic contaminants in subsoil horizons and effects of dissolved organic matter related to organic waste recycling practices.

    Science.gov (United States)

    Chabauty, Florian; Pot, Valérie; Bourdat-Deschamps, Marjolaine; Bernet, Nathalie; Labat, Christophe; Benoit, Pierre

    2016-04-01

    Compost amendment on agricultural soil is a current practice to compensate the loss of organic matter. As a consequence, dissolved organic carbon concentration in soil leachates can be increased and potentially modify the transport of other solutes. This study aims to characterize the processes controlling the mobility of dissolved organic matter (DOM) in deep soil layers and their potential impacts on the leaching of organic contaminants (pesticides and pharmaceutical compounds) potentially present in cultivated soils receiving organic waste composts. We sampled undisturbed soil cores in the illuviated horizon (60-90 cm depth) of an Albeluvisol. Percolation experiments were made in presence and absence of DOM with two different pesticides, isoproturon and epoxiconazole, and two pharmaceutical compounds, ibuprofen and sulfamethoxazole. Two types of DOM were extracted from two different soil surface horizons: one sampled in a plot receiving a co-compost of green wastes and sewage sludge applied once every 2 years since 1998 and one sampled in an unamended plot. Results show that DOM behaved as a highly reactive solute, which was continuously generated within the soil columns during flow and increased after flow interruption. DOM significantly increased the mobility of bromide and all pollutants, but the effects differed according the hydrophobic and the ionic character of the molecules. However, no clear effects of the origin of DOM on the mobility of the different contaminants were observed.

  16. Environmental impact assessment of leachate recirculation in landfill of municipal solid waste by comparing with evaporation and discharge (EASEWASTE).

    Science.gov (United States)

    Xing, Wei; Lu, Wenjing; Zhao, Yan; Zhang, Xu; Deng, Wenjing; Christensen, Thomas H

    2013-02-01

    In some arid regions where landfill produces minimal amount of leachate, leachate recirculation is suggested as a cost-effective option. However, its long-term impacts to environment remain disputed. For the purpose of revealing the environmental impacts of leachate recirculation in landfill, four scenarios were modeled using EASEWASTE, comparing the strategies of leachate recirculation (with or without gas management), evaporation and discharge. In the current situation (Scenario A), a total of 280 t of waste was generated and then transported to a conventional landfill for disposal. A number of contaminants derived from waste can be stored in the landfill for long periods, with 11.69 person equivalent (PE) for stored ecotoxicity in water and 29.62 PE for stored ecotoxicity in soil, considered as potential risks of releasing to the environment someday. Meanwhile, impacts to ecotoxicity and human toxicity in surface water, and those to groundwater, present relatively low levels. In Scenario B, leachate evaporation in a collecting pool has minimal impacts on surface water. However, this strategy significantly impacts groundwater (1055.16 PE) because of the potential infiltration of leachate, with major contaminants of As, ammonia, and Cd. A number of ions, such as Cl(-), Mg(2+), and Ca(2+), may also contaminate groundwater. In Scenario C, the direct discharge of leachate to surface water may result in acidification (2.71 PE) and nutrient enrichment (2.88 PE), primarily attributed to soluble ammonia in leachate and the depositional ammonia from biogas. Moreover, the direct discharge of leachate may also result in ecotoxicity and human toxicity via water contaminated by heavy metals in leachate, with 3.96 PE and 11.64 PE respectively. The results also show that landfill gas is the main contributor to global warming and photochemical ozone formation due to methane emission. In Scenario D, landfill gas flaring was thus be modeled and proven to be efficient for reducing

  17. Charcoal in Organic Horizon and Surface Mineral Soil in a Boreal Forest Fire Chronosequence of Western Quebec: Stocks, Depth Distribution, Chemical Properties and a Synthesis of Related Studies

    Directory of Open Access Journals (Sweden)

    Caroline M. Preston

    2017-11-01

    Full Text Available Wildfires are a major driver of carbon stocks and ecosystem development in Canadian boreal forests, but there is little information on amounts and properties of the charcoal produced. Using data and samples available from a previous study, we determined amounts, depth distribution and chemical properties of visually-determined charcoal (>2 mm in a boreal chronosequence in the Abitibi region of Quebec, Canada. Sites ranged from 24 to 2,355 years since fire (ysf and originated from low- and high-severity soil burns (>5 or <5 cm organic horizon unburned, respectively. Two or three pits were sampled at 1-cm depth intervals from 20 jack pine (Pinus banksiana sites (one low severity and 19 high severity and 31 black spruce (Picea mariana sites (12 low severity and 19 high severity. Site-level charcoal stocks ranged from 50 to 5,527 kg ha−1 with high within-site variability and lower stocks for the oldest sites. Depth distributions typically peaked around the organic-mineral interface, but some low-severity sites also had charcoal layers within the organic horizon. Means from 30 charcoal samples were 569 mg g−1 total C, 4.1 mg g−1 total N and 140 C/N (molar, with total C and C/N showing a trend of decline with time since fire, and total N showing an increase. Solid-state 13C CPMAS NMR spectra of nine samples showed high variability among the younger samples, but a trend to higher aromaticity for the older ones. A literature survey focusing on boreal forests similarly showed highly variable stocks and chemical properties of charcoal in organic horizon and upper mineral soil, with reduction of variance and lower stocks after several hundred years. This initial variation was also consistent with reports of highly variable temperatures and duration of charring in wildfires. Adding reports available for char production, and considering that most studies of char stocks and production are limited to the organic horizon (forest floor, suggests that

  18. THE STRIPPING OF AMMONIA FROM LANDFILL LEACHATE IN PLUG FLOW REACTORS

    Directory of Open Access Journals (Sweden)

    Danuza Costa Campos

    2010-10-01

    Full Text Available The leachate is a highly liquid polluting, considering, besides high concentrations of ammonia nitrogen. Treating leachate is a very difficult task once its composition is very complex. A king of treatment that is being developed is the stripping of ammonia where this chemical will be removed from the leachate by mass transfer of the liquid phase to gas. Therefore, this paper addressed to study the ammonia stripping process in leachates liquids using plug-flow reactors in series. In order to accomplish the experimental part four plugflow reactors in series were build, with an average height of 50 centimeters, without forced air supplier and without leachate pH adjustment. The leachate sample used was from the metropolitan landfill of Joao Pessoa city, which was collected and transported to the EXTRABES laboratory and made the physicochemical characterization. The experimental monitoring system consisted of four distinct phases, with applied superficial loads of 450, 500, 600 and 700 kg NH4+ ha-1 day-1, hydraulic detention time equal to 65, 60, 50 and 38 days, and it was obtained an average efficiency of ammonia nitrogen removal around 96.1%, 99.7%, 99.5% and 98.5% respectively. It was found that the removal efficiency of NH3 was satisfactory in all phases, however, the kinetic study showed that the higher the surface charge applied to the reactors, the higher the rate constant for removal of NH3 stripping process. Thus we can conclude that the process of stripping ammonia from landfill leachate may be done in plug-flow reactors in series, with an average depth of 50 cm, due to provide high removal efficiency of ammonia nitrogen, with low operating costs.

  19. Effect of leachate solutions from fly and bottom ash on groundwater quality

    Science.gov (United States)

    Kopsick, Deborah A.; Angino, Ernest E.

    1981-12-01

    Leaching experiments on fly and bottom ash for Ca, Mg, Na, K, Fe, Mn, Zn, Cu and Pb indicated a potential for contamination of ground- and surface-water supplies. Due to the variability in chemical composition of coals, it is difficult to make generalizations concerning the chemistry of leachate solutions from the ashes of the coals. A decrease in concentration with time of leaching was observed for all elements, except for Ca which was released at a constant rate. Fly ash from a Missouri coal generated a leachate enriched in Pb, Zn, Cu, Fe, Mn and Cd, reflective of the high Pb/1bZn mineralization present in the surrounding area. With a pH of 3.0 this ash has the greatest potential for groundwater contamination. Conversely, leachates from Wyoming fly and bottom ashes exhibited low trace-metal concentrations. These same solutions were high in K, Na, Ca and Mg, and also showed strong pozzolanic behvior, which will reduce the leachability of these ashes. In most instances, fly and bottom ash from Kentucky and Illinois coals yielded leachates intermediate in elemental composition to leachates of Missouri and Wyoming coal ashes. Leaching experiments indicate that it is not valid to predict the chemistry of leachates from fly and bottom ash based solely on the chemical composition of the ash. From the limited number of parameters and sites examined in this study, it is clear that many of the problems related to leachates from fly and bottom ash and gob piles are site specific as well as specific to the source of coal burned. These results are, nevertheless, indicative of problems likely to be encountered in working with these materials.

  20. VMware Horizon Workspace essentials

    CERN Document Server

    von Oven, Peter; Lindberg, Joel

    2014-01-01

    This book uses a step-by-step approach to teach you how to design, deploy, and manage a Horizon Workspace based on real world experience. Written in an easy-to-follow style, this book explains the terminology in a clear and concise manner. Each feature is explained starting at a high level and then drilling down into the technical detail, using diagrams and screenshots.This book is perfect for IT administrators who want to deploy a solution to centrally manage access to corporate applications, data, and virtual desktops using Horizon Workspace. You need to have some experience in delivering BY

  1. Mastering VMware Horizon 6

    CERN Document Server

    Oven, Peter von

    2015-01-01

    If you are working as a desktop admin, part of a EUC team, an architect, or a consultant on a desktop virtualization project and you are looking to use VMware's Horizon solution, this book is for you. This book will demonstrate the new capabilities of Horizon 6. You should have experience in desktop management using Windows and Microsoft Office, and be familiar with Active Directory, SQL, Windows Remote Desktop Session Hosting, and VMware vSphere infrastructure (ESXi and vCenter Server) technology.

  2. Leachate from market refuse and biomethanation study.

    Science.gov (United States)

    Mukherjee, S N; Kumar, Sunil

    2007-12-01

    The market place is considered to be an important centre of daily life of campus community. In India, as in Europe and the USA, other forms of shopping have emerged significantly and now predominate, for instance department stores and supermarkets. Though, it is suffered from poor waste management, but the place could be a potential source for obtaining non-conventional energy. The present study examined the quality of market waste management of the Indian Institute of Technology Campus along with the feasibility of biogas production from leachate generated in the waste. Solid wastes from different storage locations of the market place were collected and analyzed. The characteristics of solid wastes were found to be degradable in nature. The wastes, composed of 85% of vegetable origin, were placed in a container and water was added to to generate leachate. The self-purification efficiency of leachate was also studied in the Indian environment and compared with research findings in the USA under an identical moisture application rate. Leachate characterization was investigated both under saturated and submerged conditions. The treatability of leachate was studied in a laboratory-scale up-flow anaerobic filter with hollow burnt clay rings as packing media. It was observed that 4,000-6,000 mg/l would be the optimum range of inlet chemical oxygen demand (COD) concentration for leachate treatment because of the inhibitory effect of ammonia, sulphide, volatile fatty acids and toxic metals in high concentrations at higher strengths of leachate. The gas production rate was found to be at a maximum at 38 degrees C and containing 70-75% methane. From experimental data, it was revealed that 83% COD was removed with input COD concentration of 5,475 mg/l at 2 days hydraulic retention time with biogas yield coefficients of 0.61. The present study also investigated the removal efficiency of chloride, ammonia, sulphide and nitrate.

  3. Application of constructed wetlands to the treatment of leachates from a municipal solid waste landfill in Ibadan, Nigeria.

    Science.gov (United States)

    Aluko, Olufemi Oludare; Sridhar, M K C

    2005-06-01

    Leachates are wastewater generated principally from landfills and solid waste disposal sites. Leachates emanating from municipal wastes are a major source of surface and groundwater pollution worldwide. Globally, leachates have been implicated in low yield of farm produce, developmental anomalies, low birth weights, leukemia incidence, and other cancers in communities around the site. They have also been implicated in hazards to the environment, loss of biodiversity, and contamination of water sources. At Aba-Eku in Nigeria, leachates are being discharged into the Omi Stream without treatment. A study was conducted on a method of leachate treatment that passes the leachate through constructed wetlands using Ipomoea aquatica (Forsk), a locally available plant found close to the landfill site. The aim of the study was to evolve a sustainable and cost-effective method of treatment whose effluents can be discharged into the Omi Stream with no or minimal impact. The study was descriptive and analytical in design. Samples were collected and analyzed with standard methods for pH, suspended solids (SS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), ammonia, nitrate, and trace metals. Raw leachates were turbid and amber in color and contained suspended solids (197.5 mg/L), ammonia (610.9 mg/L), lead (1.64 mg/L), iron (198.10 mg/L), and manganese (23.20 mg/L). When the leachates were passed through the constructed wetland with eight hours' detention time, effluents showed significant reductions in suspended solids (81.01 percent), BOD (86.03 percent), and ammonia (97.77 percent). The study shows that a constructed wetland is a feasible tool for the treatment of leachates before their disposal into the environment in Nigeria and can help safeguard environmental quality.

  4. Optimal investment horizons

    Science.gov (United States)

    Simonsen, I.; Jensen, M. H.; Johansen, A.

    2002-06-01

    In stochastic finance, one traditionally considers the return as a competitive measure of an asset, i.e., the profit generated by that asset after some fixed time span Δt, say one week or one year. This measures how well (or how bad) the asset performs over that given period of time. It has been established that the distribution of returns exhibits ``fat tails'' indicating that large returns occur more frequently than what is expected from standard Gaussian stochastic processes [1-3]. Instead of estimating this ``fat tail'' distribution of returns, we propose here an alternative approach, which is outlined by addressing the following question: What is the smallest time interval needed for an asset to cross a fixed return level of say 10%? For a particular asset, we refer to this time as the investment horizon and the corresponding distribution as the investment horizon distribution. This latter distribution complements that of returns and provides new and possibly crucial information for portfolio design and risk-management, as well as for pricing of more exotic options. By considering historical financial data, exemplified by the Dow Jones Industrial Average, we obtain a novel set of probability distributions for the investment horizons which can be used to estimate the optimal investment horizon for a stock or a future contract.

  5. Treatability of stabilize landfill leachate by using pressmud ash as an adsorbent

    Science.gov (United States)

    Azme, N. N. Mohd; Murshed, M. F.

    2018-04-01

    Leachate is a liquid produced from the landfill that contains high concentration of heavy metals, chemicals and nutrient loading. The treatability of these contaminants are complicated since the current treatment technology are costly and site specific. Therefore, this study was conducted to evaluate the treatability of stabilized landfill leachate by using waste (pressmud ash) as an absorbent. Pressmud ash was prepared by burning at different temperature from 100 to 700 degree Celsius and test at 24 hours shaking time, pH 8, and 4000 rpm. Leachate samples were collected from municipal solid waste (MSW) Pulau Burung Sanitary Landfill (PBSL) and were analyzed for heavy metal, COD, ammonia and colour. This study was performed in two phases i) leachate characteristic, ii) treatability assessment by using pressmud ash. Pressmud was sampled from the sugar mill, Malaysian Sugar Manufacturing (MSM) Sdn Bhd, Seberang Perai, Pulau Pinang. The pressmud with 400°C are highly potential material with a low cost which can be a good adsorbent was capable reducing efficiencies of COD (60.76%), ammonia (64.37%) and colour (35.78%) from real wastewater leachate. Pressmud showed good sorption capability. Surface modification with burning greatly enhanced the reducing efficiency of sugar waste based adsorbent with adsorption efficiency.

  6. Nitrogen Removal from Landfill Leachate by Microalgae

    Science.gov (United States)

    Pereira, Sérgio F. L.; Gonçalves, Ana L.; Moreira, Francisca C.; Silva, Tânia F. C. V.; Vilar, Vítor J. P.; Pires, José C. M.

    2016-01-01

    Landfill leachates result from the degradation of solid residues in sanitary landfills, thus presenting a high variability in terms of composition. Normally, these effluents are characterized by high ammoniacal-nitrogen (N–NH4+) concentrations, high chemical oxygen demands and low phosphorus concentrations. The development of effective treatment strategies becomes difficult, posing a serious problem to the environment. Phycoremediation appears to be a suitable alternative for the treatment of landfill leachates. In this study, the potential of Chlorella vulgaris for biomass production and nutrients (mainly nitrogen and phosphorus) removal from different compositions of a landfill leachate was evaluated. Since microalgae also require phosphorus for their growth, different loads of this nutrient were evaluated, giving the following N:P ratios: 12:1, 23:1 and 35:1. The results have shown that C. vulgaris was able to grow in the different leachate compositions assessed. However, microalgal growth was higher in the cultures presenting the lowest N–NH4+ concentration. In terms of nutrients uptake, an effective removal of N–NH4+ and phosphorus was observed in all the experiments, especially in those supplied with phosphorus. Nevertheless, N–NO3− removal was considered almost negligible. These promising results constitute important findings in the development of a bioremediation technology for the treatment of landfill leachates. PMID:27869676

  7. Nitrogen Removal from Landfill Leachate by Microalgae.

    Science.gov (United States)

    Pereira, Sérgio F L; Gonçalves, Ana L; Moreira, Francisca C; Silva, Tânia F C V; Vilar, Vítor J P; Pires, José C M

    2016-11-17

    Landfill leachates result from the degradation of solid residues in sanitary landfills, thus presenting a high variability in terms of composition. Normally, these effluents are characterized by high ammoniacal-nitrogen (N-NH₄⁺) concentrations, high chemical oxygen demands and low phosphorus concentrations. The development of effective treatment strategies becomes difficult, posing a serious problem to the environment. Phycoremediation appears to be a suitable alternative for the treatment of landfill leachates. In this study, the potential of Chlorella vulgaris for biomass production and nutrients (mainly nitrogen and phosphorus) removal from different compositions of a landfill leachate was evaluated. Since microalgae also require phosphorus for their growth, different loads of this nutrient were evaluated, giving the following N:P ratios: 12:1, 23:1 and 35:1. The results have shown that C. vulgaris was able to grow in the different leachate compositions assessed. However, microalgal growth was higher in the cultures presenting the lowest N-NH₄⁺ concentration. In terms of nutrients uptake, an effective removal of N-NH₄⁺ and phosphorus was observed in all the experiments, especially in those supplied with phosphorus. Nevertheless, N-NO₃ - removal was considered almost negligible. These promising results constitute important findings in the development of a bioremediation technology for the treatment of landfill leachates.

  8. Nitrogen Removal from Landfill Leachate by Microalgae

    Directory of Open Access Journals (Sweden)

    Sérgio F. L. Pereira

    2016-11-01

    Full Text Available Landfill leachates result from the degradation of solid residues in sanitary landfills, thus presenting a high variability in terms of composition. Normally, these effluents are characterized by high ammoniacal-nitrogen (N–NH4+ concentrations, high chemical oxygen demands and low phosphorus concentrations. The development of effective treatment strategies becomes difficult, posing a serious problem to the environment. Phycoremediation appears to be a suitable alternative for the treatment of landfill leachates. In this study, the potential of Chlorella vulgaris for biomass production and nutrients (mainly nitrogen and phosphorus removal from different compositions of a landfill leachate was evaluated. Since microalgae also require phosphorus for their growth, different loads of this nutrient were evaluated, giving the following N:P ratios: 12:1, 23:1 and 35:1. The results have shown that C. vulgaris was able to grow in the different leachate compositions assessed. However, microalgal growth was higher in the cultures presenting the lowest N–NH4+ concentration. In terms of nutrients uptake, an effective removal of N–NH4+ and phosphorus was observed in all the experiments, especially in those supplied with phosphorus. Nevertheless, N–NO3− removal was considered almost negligible. These promising results constitute important findings in the development of a bioremediation technology for the treatment of landfill leachates.

  9. Combined Treatment of Old Sanitary Landfill Leachate

    Directory of Open Access Journals (Sweden)

    Visnja Orescanin

    2016-06-01

    Full Text Available Landfill leachate presents hardly treatable, highly complex and very toxic environmental effluent originated in the municipal solid waste degradation process. Although, numerous treatment methods were developed so far, none of them alone could achieve permissible limits of the primary pollutants to discharge into natural recipients. The current study aimed to develop and apply the process to treat landfill leachate by simultaneous application of electrochemical methods, ultrasound, electromagnetic field and ozonation to achieve the legal criteria for its discharge into natural recipient and minimize its adverse environmental impacts. For this purpose, old landfill leachate was taken from the Piskornica (Koprivnica, Croatia sanitary landfill. Prior to the treatment, the leachate was supplemented with NaCl (2 g/L and subjected to simultaneous treatment with stainless steel electrode plates, ultrasound and recirculation through electromagnetic field. After 45 minutes, stainless steel electrode plates were replaced by iron electrodes and treated for another 10 minutes followed by 15 minutes of the treatment with aluminum electrode plates. Ultrasound and recirculation through electromagnetic field were also applied during Fe and Al electrode treatment. Finally, the electrodes were removed and the suspension was mixed with ozone for another 30 minutes and allowed to settle for an hour. Following the combined treatment, the removal efficiency for the turbidity, color, suspended solids, ammonium, phosphates and heavy metals was 99% or higher, while the removal of COD was 97%. All the measured parameters in the treated leachate were lower compared to upper permissible limit for discharge into natural recipient.

  10. Measurement of biochemical oxygen demand of the leachates.

    Science.gov (United States)

    Fulazzaky, Mohamad Ali

    2013-06-01

    Biochemical oxygen demand (BOD) of the leachates originally from the different types of landfill sites was studied based on the data measured using the two manometric methods. The measurements of BOD using the dilution method were carried out to assess the typical physicochemical and biological characteristics of the leachates together with some other parameters. The linear regression analysis was used to predict rate constants for biochemical reactions and ultimate BOD values of the different leachates. The rate of a biochemical reaction implicated in microbial biodegradation of pollutants depends on the leachate characteristics, mass of contaminant in the leachate, and nature of the leachate. Character of leachate samples for BOD analysis of using the different methods may differ significantly during the experimental period, resulting in different BOD values. This work intends to verify effect of the different dilutions for the manometric method tests on the BOD concentrations of the leachate samples to contribute to the assessment of reaction rate and microbial consumption of oxygen.

  11. Effect of dilution and operating parameters on ammonia removal from scheduled waste landfill leachate in a lab-scale ammonia stripping reactor

    Science.gov (United States)

    Hanira, N. M. L.; Hasfalina, C. M.; Rashid, M.; Luqman, C. A.; Abdullah, A. M.

    2017-06-01

    A lab-scale ammonia stripping reactor was used to treat raw and diluted (1:1) scheduled waste landfill (SWL) leachate containing ammonia-nitrogen (NH3-N). Operating parameters such as air-liquid ratio, hydrated lime [Ca(OH)2] dosage, types of packing materials and packing heights were investigated with central composite design (CCD) of response surface methodology (RSM) was used to optimize the parameters affecting NH3-N removal from the leachate. The percentage removal on turbidity, colour and phosphate were also evaluated in this study. It was observed that the optimal conditions obtained from desirable response (NH3-N removal) for raw leachate were predicted at air-liquid ratio of 70, Ca(OH)2 dosage of 5 gL-1, packing height of 60 cm and types of packing material was number 3 (non-woven polyester) while for diluted leachate these were 70, 6 gL-1, 60 cm and Type 3 (non-woven polyester), respectively. Quadratic RSM predicted the maximum NH3-N removal to be 78% for raw leachate and 81% for diluted leachate at these optimal conditions concurred with the experiment which successfully removed 76% and 80% of NH3-N, respectively. However, higher removal efficiencies of turbidity (97%), colour (88%) and phosphate (93%) was observed in the treatment with diluted leachate compared to raw leachate merely up to 55%, 34% and 49%, respectively. The finding showed that the difference in the removal of NH3-N in diluted and raw SWL leachate was insignificant. However, turbidity, colour and phosphate showed a significant reduction in the diluted leachate during the treatment. The study suggests that the dilution of SWL leachate does not present a significant effect on the removal of ammonia in the stripping reactor.

  12. Leachate characterization and performance evaluation of leachate treatment plant in Cipayung landfill, Indonesia

    Science.gov (United States)

    Noerfitriyani, E.; Hartono, D. M.; Moersidik, S. S.; Gusniani, I.

    2018-01-01

    The operation of landfill can cause environmental problems due to waste decomposition in the form of leachate production. Cipayung Landfill has a leachate treatment plant using stabilization ponds. The objective of this research is to evaluate the performance of stabilization ponds at Cipayung Landfill. The data were analyzed based on leachate samples from treatment unit’s influent and effluent under rainy season condition from April to May 2017. The results show the average leachate quality based on parameters of temperature by 34.81°C, Total Suspended Solid (TSS) of 72.33 mg/L, pH of 7.83, Biochemical Oxygen Demand (BOD) of 3,959.63 mg/L, Chemical Oxygen Demand (COD) of 6,860 mg/L, Total Nitrogen of 373.33 mg/L, and heavy metal Mercury of 0.0016 mg/L. The treatment plant’s effluent quality exceeds the leachate standard limit based on Indonesia’s Ministry of Environment and Forestry Law No. 59 of 2016. The results of design evaluation show that the anaerobic pond, facultative pond, and maturation pond system do not meet the design criteria. Therefore, a design improvement is needed to increase the performance of the leachate treatment plant and to ensure that the leachate discharged to water bodies does not exceed the standard limit to prevent contamination of the environment.

  13. Spacetimes containing slowly evolving horizons

    International Nuclear Information System (INIS)

    Kavanagh, William; Booth, Ivan

    2006-01-01

    Slowly evolving horizons are trapping horizons that are ''almost'' isolated horizons. This paper reviews their definition and discusses several spacetimes containing such structures. These include certain Vaidya and Tolman-Bondi solutions as well as (perturbatively) tidally distorted black holes. Taking into account the mass scales and orders of magnitude that arise in these calculations, we conjecture that slowly evolving horizons are the norm rather than the exception in astrophysical processes that involve stellar-scale black holes

  14. Nubi et al., (SWJ): 17-20 Impact Assessment Of Dumpsite Leachate ...

    African Journals Online (AJOL)

    Dr Ahmed

    yet achieved in many countries, even in the developed ones. Many of the recommended ways of waste disposal have been proven to be ineffective and some even pose further hazards. The aim of this study is to assess the impact of dumpsite leachate on the qualities of surface water and sediment of the River Eku, a water ...

  15. Semi-continuous anaerobic treatment of fresh leachate from ...

    African Journals Online (AJOL)

    A semi-continuous leachate treatment process was developed in the present study. The fresh leachate was obtained from a municipal solid waste transfer station and palm oil mill effluent (POME) sludge was used as sources of anaerobic microbial complex. The semi-continuous treatment of leachate was operated in two ...

  16. Migration of Leachate from Uncollected Solid Waste Dumpsite ...

    African Journals Online (AJOL)

    This paper examines the composition and concentration of leachates from a dumpsite in Nairobi University and the variation of the concentration of the constituents of the leachate with depth. Soil samples at varying depths below the dumpsite and solid waste samples at the dumpsite were subjected to synthetic leachate ...

  17. Water reduction by constructed wetlands treating waste landfill leachate in a tropical region.

    Science.gov (United States)

    Ogata, Yuka; Ishigaki, Tomonori; Ebie, Yoshitaka; Sutthasil, Noppharit; Chiemchaisri, Chart; Yamada, Masato

    2015-10-01

    One of the key challenges in landfill leachate management is the prevention of environmental pollution by the overflow of untreated leachate. To evaluate the feasibility of constructed wetlands (CWs) for the treatment of waste landfill leachate in tropical regions, water reduction and pollutant removal by a CW subjected to different flow patterns (i.e., horizontal subsurface flow (HSSF) and free water surface (FWS)) were examined in both rainy and dry seasons in Thailand. A pilot-scale CW planted with cattail was installed at a landfill site in Thailand. With HSSF, the CW substantially removed pollutants from the landfill leachate without the need to harvest plants, whereas with FWS, it only slightly removed pollutants. Under both flow patterns, the CW significantly reduced the leachate volume to a greater extent than surface evaporation, which is regarded as an effect of the storage pond. Additionally, water reduction occurred regardless of season and precipitation, within the range 0-9 mm d(-1). In the case of low feeding frequency, water reduction by the CW with HSSF was lower than that with FWS. However, high feeding frequency improved water reduction by the CW with HSSF and resulted in a similar reduction to that observed with FWS, which exhibited maximum evapotranspiration. In terms of water reduction, with both HSSF in conjunction with high frequency feeding and FWS, the CW provided a high degree of evapotranspiration. However, pollutant removal efficiencies with HSSF were higher than for FWS. The present study suggested that CWs with HSSF and high frequency feeding could be useful for the prevention of uncontrollable dispersion of polluted leachate in the tropical climate zone. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Locating the Gribov horizon

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Fei; Qin, Si-Xue; Roberts, Craig D.; Rodríguez-Quintero, Jose

    2018-02-01

    We explore whether a tree-level expression for the gluon two-point function, supposed to express effects of an horizon term introduced to eliminate the Gribov ambiguity, is consistent with the propagator obtained in simulations of lattice-regularised quantum chromodynamics (QCD). In doing so, we insist that the gluon two-point function obey constraints that ensure a minimal level of consistency with parton-like behaviour at ultraviolet momenta. In consequence, we are led to a position which supports a conjecture that the gluon mass and horizon scale are equivalent emergent massscales, each with a value of roughly 0.5 GeV; and wherefrom it appears plausible that the dynamical generation of a running gluon mass may alone be sufficient to remove the Gribov ambiguity.

  19. Locating the Gribov horizon

    Science.gov (United States)

    Gao, Fei; Qin, Si-Xue; Roberts, Craig D.; Rodríguez-Quintero, Jose

    2018-02-01

    We explore whether a tree-level expression for the gluon two-point function, supposed to express effects of an horizon term introduced to eliminate the Gribov ambiguity, is consistent with the propagator obtained in simulations of lattice-regularized quantum chromodynamics (QCD). In doing so, we insist that the gluon two-point function obey constraints that ensure a minimal level of consistency with parton-like behavior on the ultraviolet domain. In consequence, we are led to a position which supports a conjecture that the gluon mass and horizon scale are equivalent emergent mass-scales, each with a value of roughly 0.5 GeV; and wherefrom it appears plausible that the dynamical generation of a running gluon mass may alone be sufficient to remove the Gribov ambiguity.

  20. Gravitational pressure, apparent horizon and thermodynamics of FLRW universe in the teleparallel gravity

    Science.gov (United States)

    da Rocha-Neto, J. F.; Morais, B. R.

    2018-04-01

    In the context of the teleparallel equivalent of general relativity the concept of gravitational pressure and gravitational energy-momentum arisen in a natural way. In the case of a Friedmann-Lemaitre-Robertson-Walker space FLRW we obtain the total energy contained inside the apparent horizon and the radial pressure over the apparent horizon area. We use these definitions to written a thermodynamics relation TAdSA = dEA+PAdVA at the apparent horizon, where EA is the total energy inside the apparent horizon, VA is the areal volume of the apparent horizon, PA is the radial pressure over the apparent horizon area, SA is the entropy which can be assumed as one quarter of the apparent horizon area only for a non stationary apparent horizon. We identify TA as the temperature at the surface of the apparent horizon. We shown that for all expanding accelerated FLRW model of universe the radial pressure is positive.

  1. Horizon 2020 in sight

    CERN Document Server

    Joannah Caborn Wengler

    2012-01-01

    Every tenth member of the CERN personnel participates in an EU-funded project – a strong indication of CERN’s successful relations with the European Commission (EC), coordinated by the CERN EU projects office. The EC director in charge of preparing “Horizon 2020”, the new EU funding programme for research and innovation (2014-2020), will be giving a presentation at CERN on 8 May. He will reveal more about what the new programme has in store.   “It’s a very interesting time in the development of Horizon 2020, which is focusing the attention of all research communities in Europe,” explains Svetlomir Stavrev, head of the EU projects office. “After a long public consultation and drafting process, the Horizon 2020 proposal documents are now being reviewed by the European Parliament and Council.” CERN already participated in the consultation, making good use of the opportunity to contribute to the shaping of wh...

  2. Paper for Publication in IOP: Conference Series Leachate Treatment using three Years Aged Lysimetric Bioreactor Models

    Science.gov (United States)

    Hartono, Djoko M.; Andari Kristanto, Gabriel; Gusniani Sofian, Irma; Fauzan, Ahmad; Mahdiana, Ghanis

    2018-03-01

    This study was conducted as a response to address the problem of land availability for Cipayung landfill that no longer able to accommodate waste generation Depok City and to protect water pollution in receiving water body. Law No. 8/2008 explained that local governments and cities are required to create a sanitary landfill as a final waste processing system to replace open dumping that had been done by almost all the final processing of waste in cities in Indonesia. Sanitary landfill is the final waste processing system that works best and is environmentally friendly. The sanitary landfill will generate leachate. Leachate is the result of precipitation, evaporation, surface runoff, water infiltration into the waste, and also including the water contained in the waste. The purpose of this study was to determine the utilization of leachate generated by three years aged reactor.This study use a modeling tools as bioreactor landfill tank or so called lysimetric, that made of the polymer material that susceptible to high heat and pressure. This bioreactor landfill tank has a diameter of 0.83 m, with a surface area of 0.54 m2 and a height of 2.02 m, with the examination duration of 115 days. This tank consists of several layer, such as sand layer, solid waste layer, water layer and piping system. These layer has 3 year aged. The In this research, leachate recirculation in bioreactor landfills was conducted with waste layered loading systems with percolation system. This research has been conducted since the beginning of 2016, sampling, field measurement and analysis of leachate and waste quality carried out for approximately 115 days of field measurements.Several parameter were measured such as pH, BOD, COD, nitrate, nitrite and TSS. From the analysis of the leachate quality parameters of pH, BOD, COD, nitrite, TSS, showed a reduction in the concentration of the three reactors. The concentration of parameters measured at the initial stage until the final stage, showed a

  3. Leachate impacts on groundwater: modeling generation and transport at the naameh landfill

    International Nuclear Information System (INIS)

    Bou-Zeid, E.; El FAdel, M.; Basha, H.

    2000-01-01

    Full text.Although municipal solid waste is now managed through integrated schemes that rank land filling as one of the least favorable options for disposal, this management alternative continues to be the most economic and attractive in the vast majority of cases. An inevitable consequence of the practice of solid waste disposal in landfills is the generation, refuse characteristics and land filling operations. Leachate migration away from the landfill boundaries and its subsequent release into the surrounding environment, present serious environmental concerns at both existing and new facilities particularly in relation to surface and ground water pollution. While numerous mathematical models have been developed to simulate processes governing leachate occurrence and behavior in landfills and their potential migration away from landfill boundaries, none have been applied at former quarries converted to waste disposal facilities. The objective of this research work is to calibrate and apply mathematical models to predict the generation, fate and transport of leachate at a former quarry landfill facility (the Naameh landfill site). The site offers unique characteristics in that it is the first quarry converted to a landfill in Lebanon and is planned to have refuse depth in excess of one hundred meters, making it one of the deepest in the world. The modeling estimates leachate quantity in order to control its associated environmental impacts, particularly on ground water wells down gradient of the site. The sensitivity of leachate generation to meteorological, operation and design parameters was assessed. Guidance for leachate control, recirculation and collection to minimize these impacts is also provided. The fate and transport of contaminants released from the landfill to the subsurface was modeled. A sensitivity analysis with respect to geological properties of the site was conducted. Worst case scenarios were investigated as well

  4. Aging geomembranes in uranium tailings leachate

    International Nuclear Information System (INIS)

    Mitchell, D.H.

    1984-01-01

    Pacific Northwest Laboratory (PNL) is performing a study to provide the US Nuclear Regulatory Commission (NRC) with a database to support licensing of uranium mill tailings ponds with geomembranes. As part of this study, geomembranes have been aged under conditions closely approximating those of uranium mill tailings ponds with acidic leachate. The aging procedure and results of tests with high density polyethylene (HDPE) and polyvinyl chloride (PVC) are presented. No degradation products were detected in the HDPE or the leachate. We expect that HDPE will not suffer significant chemical attack by uranium tailings and acidic leachate over the active life (20 years or less) of a pond. Because no large changes in physical properties were observed, we expect that changes in the physical properties of HDPE will be minor at mill tailings ponds with acidic leachate. Although testing is still underway, the PVC geomembrane has undergone some chemical reactions. Elongation declined as exposure temperatures increased, while other physical properties remained constant. The amount of aging simulated will be estimated when chemical analyses on PVC samples are completed. 11 references, 3 figures, 4 tables

  5. Nonequilibrium free diffusion in seed leachate

    Science.gov (United States)

    Ortiz G., Luis; Riquelme P., Pablo; Guzmán, R.

    2013-11-01

    In this work, we use a Schlieren-like Near Field Scattering (SNFS) setup to study nonequilibrium free diffusion behavior of a colloidal solution obtained from seeds leachate. The main objective is to compare the temporal behavior of the diffusion coefficient of seed leachate with an electric conductivity based vigor test. SNFS sizing measurements, based on Mie theory, were carried out to ensure its reliability and sensitivity. Then, we performed a typical nonequilibrium free diffusion experiment of a glycerol-water mixture. In this way, we confirmed that SNFS setup is sensitive to giant concentration fluctuations of nanocolloidal solutions. The results obtained in this stage reproduce properly the data reported elsewhere in literature. Moreover, seed leachate diffuse, in water, in a similar way that glycerol does. In both cases we used the same method (dynamic structure factor) to determine thermo-physical properties. We show that time evolution of diffusion coefficient of Lupinus Albus leachate exhibits three defined regimes as electric conductivity measurements. The results also exhibit a correspondence between the behavior of the diffusion coefficient and electric conductivity values of the two regions in the temporal range studied. Finally, we discuss biological processes involved in germination that could modulate this dependence, and the role played by the electrolytic nature of solutes.

  6. A framework for assessment and characterisation of municipal solid waste landfill leachate: an application to the Turbhe landfill, Navi Mumbai, India.

    Science.gov (United States)

    Mishra, Harshit; Rathod, Merwan; Karmakar, Subhankar; Kumar, Rakesh

    2016-06-01

    Rapid industrialisation, growing population and changing lifestyles are the root causes for the generation of huge amounts of solid waste in developing countries. In India, disposal of municipal solid waste (MSW) through open dumping is the most common waste disposal method. Unfortunately, leachate generation from landfill is high due to the prolonged and prominent monsoon season in India. As leachate generation rate is high in most of the tropical countries, long-term and extensive monitoring efforts are expected to evaluate actual environmental pollution potential due to leachate contamination. However, the leachate characterisation involves a comprehensive process, which has numerous shortcomings and uncertainties possibly due to the complex nature of landfilling process, heterogeneous waste characteristics, widely varying hydrologic conditions and selection of analytes. In order to develop a sustainable MSW management strategy for protecting the surface and ground water resources, particularly from MSW landfill leachate contamination, assessment and characterisation of leachate are necessary. Numerous studies have been conducted in the past to characterise leachate quality from various municipal landfills; unfortunately, none of these propose a framework or protocol. The present study proposes a generic framework for municipal landfill leachate assessment and characterisation. The proposed framework can be applied to design any type of landfill leachate quality monitoring programme and also to facilitate improved leachate treatment activities. A landfill site located at Turbhe, Navi Mumbai, India, which had not been investigated earlier, has been selected as a case study. The proposed framework has been demonstrated on the Turbhe landfill site which is a comparatively new and the only sanitary landfill in Navi Mumbai.

  7. The test ability of fish Tawes to leachate garbage dump (TPA) Benowo

    Science.gov (United States)

    Juliardi AR, N. R.; Wiyanti, R. I.

    2018-01-01

    Leachate is a liquid from waste containing elements of dissolved and suspended elements. Garbage collected at the landfill site contains organic, inorganic and heavy metal substances. If the rains will produce leachate with mineral content, organic and heavy metals. When the condition or leachate flow in let to the soil surface can cause negative effects to the surrounding environment including for humans. Toxicity test it was conducted to determine the level of leachate toxicity of the test animals living in surface water located around of the “TPA Benowo”. In this study using Tawes fish with length between 4-6 cm. In this toxicity test is done in 2 stages, namely: range finding test, the search for this range is obtained 0% concentrations (as control) 0,3%; 0,6%; 0,9%; 0,12% and 0,15%. The next stage of toxicity acute test, at this stage of toxicity concentration do smaller again that is: 0,18%; 0,36%; 0,54%; 0,72% and 0,9%. The results obtained LC50 value of 0,385%, while eyes, brown stomach skin.

  8. Effect of flue gas desulfurization residue on plant establishment and soil and leachate quality

    Energy Technology Data Exchange (ETDEWEB)

    Punshon, T.; Adriano, D.C.; Weber, J.T. [University of Georgia, Savannah, GA (USA). Savannah River Ecology Lab.

    2001-06-01

    Effects on soil quality and crop establishment after incorporation of flue gas desulfurization by-product (FGD) into soil as an amendment was assessed in a mesocosm study. Mesocosm units received applications equivalent to 0, 2.5, 5.0, 7.5 and 10% FGD residue. Germination, biomass production, and elemental composition of corn, radish and cotton were determined. The quality of leachates and soil were also determined periodically. Flue gas desulfurization residue did not affect germination and all application rates stimulated aboveground biomass. Plants grown in FGD-amended soil contained significantly elevated tissue concentrations of As, B, Se, and Mo. The FGD residue elevated surface soil pH from 5.5 to 8.1. Leachate pH was unaffected by FGD, but salinity rose sharply with increasing application rates of FGD. Leachates contained higher concentrations of B, with small increases in Se and As. Flue gas desulfurization residue application caused an increase in total B, As, Mo, Se and extractable Ca in the soil, but decreased Mn and Zn. Using FGD residues could have beneficial effects on crop establishment without detrimental effects on soil or leachate quality, at an optimum rate of approximately 2.5%. This material could alleviate surface acidity, and B and Mo deficiencies in plants. 27 refs., 6 figs., 4 tabs.

  9. Expanding Your Horizon 2015

    CERN Multimedia

    Kaltenhauser, Kristin

    2015-01-01

    Expanding your horizons is a bi-annual “Science Day” for girls aged 11 to 14, held at the University of Geneva on 14 November. The girls had the opportunity to take part in hands-on workshops held by local professional women in the field of science, mathematics, engineering and technology. For the fourth time, CERN was part of this event, offering three workshops as well as a booth at the Discovery Fair, including Higgnite, an interactive visualization of the Higgs Field.

  10. VMware Horizon Mirage essentials

    CERN Document Server

    Von Oven, Peter

    2013-01-01

    This book provides a practical, step-by-step approach to teach you how to build a successful infrastructure.This book is perfect for desktop administrators who want to deploy a solution to centrally manage their endpoint images across their entire estate using VMware Horizon Mirage. You need to have some experience in desktop image management using Microsoft Windows operating systems and Windows applications, as well as be familiar with Active Directory, SQL, IIS, and general server infrastructure relating to supporting end users.

  11. Horizons of cosmology

    CERN Document Server

    Silk, Joseph

    2011-01-01

    Horizons of Cosmology: Exploring Worlds Seen and Unseen is the fourth title published in the Templeton Science and Religion Series, in which scientists from a wide range of fields distill their experience and knowledge into brief tours of their respective specialties. In this volume, highly esteemed astrophysicist Joseph Silk explores the vast mysteries and speculations of the field of cosmology in a way that balances an accessible style for the general reader and enough technical detail for advanced students and professionals. Indeed, while the p

  12. Optimization of electrocoagulation process for the treatment of landfill leachate

    Science.gov (United States)

    Huda, N.; Raman, A. A.; Ramesh, S.

    2017-06-01

    The main problem of landfill leachate is its diverse composition comprising of persistent organic pollutants (POPs) which must be removed before being discharge into the environment. In this study, the treatment of leachate using electrocoagulation (EC) was investigated. Iron was used as both the anode and cathode. Response surface methodology was used for experimental design and to study the effects of operational parameters. Central Composite Design was used to study the effects of initial pH, inter-electrode distance, and electrolyte concentration on color, and COD removals. The process could remove up to 84 % color and 49.5 % COD. The experimental data was fitted onto second order polynomial equations. All three factors were found to be significantly affect the color removal. On the other hand, electrolyte concentration was the most significant parameter affecting the COD removal. Numerical optimization was conducted to obtain the optimum process performance. Further work will be conducted towards integrating EC with other wastewater treatment processes such as electro-Fenton.

  13. Copper speciation in municipal solid waste incinerator bottom ash leachates; Kopparformer i lakvatten fraan energiaskor

    Energy Technology Data Exchange (ETDEWEB)

    Olsson, Susanna; Gustafsson, Jon Petter [Royal Inst. of Tech., Stockholm (Sweden); Schaik, Joris van; Berggren Kleja, Dan [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden); Hees, Patrick van [Oerebro Univ. (Sweden)

    2006-03-15

    The formation of copper (Cu) complexes with dissolved organic carbon (DOC) in bottom ash from municipal solid waste incineration (MSWI) may increase the total amount of Cu released but at the same time reduce its toxicity. In this study, DOC in a MSWI bottom ash leachate was characterized and the Cu-binding properties of different DOC fractions in the ash leachate and in a soil solution were studied. This knowledge may be used for improved environmental assessment of MSWI bottom ash in engineering applications. The Cu{sup 2+} activity at different pH values was measured potentiometrically using a Cu-ion selective electrode (Cu-ISE). Experimental copper complexation results were compared to speciation calculations made in Visual MINTEQ with the NICA-Donnan model and the Stockholm Humic Model (SHM). The MSWI bottom ash leachate contained a larger proportion of hydrophilic organic carbon than the investigated soil solution and other natural waters. The hydrophilic fraction of both samples showed Cu{sup 2+} binding properties similar to that of the bulk, cation-exchanged, leachate. For the ash leachate, the pH dependence of the Cu activity was not correctly captured by neither the SHM nor the NICA-Donnan model, but for the soil solution the model predictions of Cu speciation were in good agreement with the obtained results. The complex formation properties of the ash DOC appears to be less pH-dependent than what is assumed for DOC in natural waters. Hence, models calibrated for natural DOC may give inconsistent simulations of Cu-DOC complexation in MSWI bottom ash leachate. A Biotic Ligand Model for Daphnia Magna was used to provide an estimate of the copper concentrations at LC50 for a simulated bottom ash leachate. It was concluded that the Cu concentrations in certain bottom ash leachates are high enough to pose an ecotoxicological risk; however, after dilution and soil sorption, the risks for neighboring water bodies are most likely negligible. Three processes were

  14. Stringy horizons II

    Energy Technology Data Exchange (ETDEWEB)

    Giveon, Amit [Racah Institute of Physics, The Hebrew University,Jerusalem 91904 (Israel); Itzhaki, Nissan [Physics Department, Tel-Aviv University,Ramat-Aviv, 69978 (Israel); Kutasov, David [EFI and Department of Physics, University of Chicago,5640 S. Ellis Av., Chicago, IL 60637 (United States)

    2016-10-28

    We show that the spectrum of normalizable states on a Euclidean SL(2, R)/U(1) black hole exhibits a duality between oscillator states and wound strings. This duality generalizes the identification between a normalizable mode of dilaton gravity on the cigar and a mode of the tachyon with winding number one around the Euclidean time circle, which plays an important role in the FZZ correspondence. It implies that normalizable states on a large Euclidean black hole have support at widely separated scales. In particular, localized states that are extended over the cap of the cigar (the Euclidian analog of the black hole atmosphere) have a component that is localized near the tip of the cigar (the analog of the stretched horizon). As a consequence of this duality, the states exhibit a transition as a function of radial excitation level. From the perspective of a low energy probe, low lying states are naturally thought of as oscillator states in the black hole atmosphere, while at large excitation level they are naturally described as wound strings. As the excitation level increases, the size of the states first decreases and then increases. This behavior is expected to be a general feature of black hole horizons in string theory.

  15. Near horizon structure of extremal vanishing horizon black holes

    Directory of Open Access Journals (Sweden)

    S. Sadeghian

    2015-11-01

    Full Text Available We study the near horizon structure of Extremal Vanishing Horizon (EVH black holes, extremal black holes with vanishing horizon area with a vanishing one-cycle on the horizon. We construct the most general near horizon EVH and near-EVH ansatz for the metric and other fields, like dilaton and gauge fields which may be present in the theory. We prove that (1 the near horizon EVH geometry for generic gravity theory in generic dimension has a three dimensional maximally symmetric subspace; (2 if the matter fields of the theory satisfy strong energy condition either this 3d part is AdS3, or the solution is a direct product of a locally 3d flat space and a d−3 dimensional part; (3 these results extend to the near horizon geometry of near-EVH black holes, for which the AdS3 part is replaced with BTZ geometry. We present some specific near horizon EVH geometries in 3, 4 and 5 dimensions for which there is a classification. We also briefly discuss implications of these generic results for generic (gauged supergravity theories and also for the thermodynamics of near-EVH black holes and the EVH/CFT proposal.

  16. Implication of Negative Temperature in the Inner Horizon of Reissner-Nordström Black Hole

    Directory of Open Access Journals (Sweden)

    Yuant Tiandho

    2017-12-01

    Full Text Available This paper reconsiders the properties of Hawking radiation in the inner horizon of a Reissner-Nordström black hole. Through the correlation between temperature and surface gravity, it is concluded that the temperature of the inner horizon is always negative and that of the outer horizon is always positive. Since negative temperature is hotter than any positive temperature, it is predicted that particle radiation from the inner horizon will move toward the outer horizon. However, unlike temperature, entropy in both horizons remains positive. Following the definition of negative temperature in the inner horizon, it is assured that the entropy of a black hole within a closed system can never decrease. By analyzing the conditions of an extremal black hole, the third law of black hole thermodynamics can be extended to multi-horizon black holes.

  17. Arsenic speciation in municipal landfill leachate.

    Science.gov (United States)

    Li, Yarong; Low, Gary K-C; Scott, Jason A; Amal, Rose

    2010-05-01

    Arsenic species in municipal landfill leachates (MLL) were investigated by HPLC-DRC-ICPMS and LC-ESI-MS/MS. Various arsenic species including arsenate (iAs(V)), arsenite (iAs(III)), monomethylarsonic acid (MMA(V)), dimethylarsinic acid (DMA(V)), as well as sulfur-containing organoarsenic species were detected. Two sulfur-containing arsenic species in a MLL were positively identified as dimethyldithioarsinic acid (DMDTA(V)) and dimethylmonothioarsinic acid (DMMTA(V)) by comparing their molecular ions, fragment patterns and sulfur/arsenic ratios with in-house synthesised thiol-organoarsenic compounds. The findings demonstrated the potential for transformation of DMA(V) to DMDTA(V) and DMMTA(V) in a DMA(V)-spiked MLL in a landfill leachate environment.

  18. Effects of coal leachates on fish gametogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, R.

    1985-04-01

    Coal leachates were examined for toxic effects on fish spermatogensis. Non-breeding mummichogs, Fundulus heteroclitus, were induced to undergo testicular recrudescence in the laboratory by 6 weeks exposure to 20C and a photoperiod of 16L:8D. Sperm production was assessed by counting condensed heads in hemacytometers after testes were homogenized for 3 min in 200 ml of 1% NaCl and 0.05% Triton X100. Analysis of variance and Duncan's multiple range test revealed a significant (P less than .001) reduction in sperm production by fish exposed to some, but not all coal leachates. Sperm production during the breeding season by six field populations of Fundulus, either adjacent to, or 2 miles upstream from coal-fired power plants were not significantly different from one another.

  19. Vinča landfill leachate characteristics prediction by the leaching method

    Directory of Open Access Journals (Sweden)

    Ćalić Nataša D.

    2006-01-01

    Full Text Available Under the newly implemented waste management policy in European Union countries, sanitary landfilling constitutes the fourth and the least preferred of the alternative management options for the disposal of solid urban wastes. Landfills generate emissions over long periods, often longer than a lifetime. The longest lasting emission is leachate: leachate production and management is now recognized as one of the greatest problems associated with the environmentally sound operation of sanitary landfills. These liquid wastes can cause considerable pollution problems by contacting the surrounding soil, ground or surface waters and, are therefore considered major pollution hazards unless precautionary measures are implemented. Landfill leachate characterization is a critical factor in establishing a corresponding effective management strategy or treatment process. This paper summarizes leachate quality indicators, and investigates the temporal variation of leachate quality from municipal solid waste. The toxicity of leachates from the municipal solid waste landfill "Vinca" in Belgrade, the capital of Serbia, was characterized using toxicity characteristics leaching procedures (TCLP. The "Vinca" landfill was established in 1978 as one of several municipal landfills. Since the 1990-ies the "Vinca" landfill has been the only operating landfill servicing the Belgrade Metropolitan area, the biggest city in Serbia, with 1,576,124 inhabitants in the larger-city area, and 1,273,651 inhabitants in the inner-city area. The total average amount of solid wastes deposited in the landfill is estimated to be 1100 tons/day. The landfill site is not lined and the tributary flows through the centre of the site-in some places directly under the mass of refuse. No consideration has been given to the protection of ground waters, surface runoff or drainage. Local authorities plan to expand the landfill by 0.4 km2 to a total of 1.3 km Chemical analysis was performed on the

  20. Resolving Lifshitz Horizons

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, Sarah; Kachru, Shamit; Wang, Huajia; /Stanford U., ITP /Stanford U., Phys. Dept. /SLAC

    2012-04-24

    Via the AdS/CFT correspondence, ground states of field theories at finite charge density are mapped to extremal black brane solutions. Studies of simple gravity + matter systems in this context have uncovered wide new classes of extremal geometries. The Lifshitz metrics characterizing field theories with non-trivial dynamical critical exponent z {ne} 1 emerge as one common endpoint in doped holographic toy models. However, the Lifshitz horizon exhibits mildly singular behaviour - while curvature invariants are finite, there are diverging tidal forces. Here we show that in some of the simplest contexts where Lifshitz metrics emerge, Einstein-Maxwell-dilaton theories, generic corrections lead to a replacement of the Lifshitz metric, in the deep infrared, by a re-emergent AdS{sub 2} x R{sup 2} geometry. Thus, at least in these cases, the Lifshitz scaling characterizes the physics over a wide range of energy scales, but the mild singularity is cured by quantum or stringy effects.

  1. Dimensional Reduction Near the Horizon

    Science.gov (United States)

    Haba, Z.

    2008-11-01

    In the Euclidean formulation of functional integration we discuss a dimensional reduction of quantum field theory near the horizon in terms of Green functions. We show that a massless scalar quantum field in D dimensions can be approximated near the bifurcate Killing horizon by a massless two-dimensional conformal field.

  2. Black strings ending on horizons

    Science.gov (United States)

    Haddad, Nidal

    2012-12-01

    We construct an approximate static gravitational solution of the Einstein equations, with negative cosmological constant, describing a test black string stretching from the boundary of the Schwarzschild-AdS5 black brane toward the horizon. The construction builds on a derivative expansion method, assuming that the black brane metric changes slowly along the black string direction. We provide a solution up to second order in derivatives, and it implies, in particular, that the black string must shrink to zero size at the horizon of the black brane. In the near-horizon region of the black brane, where the two horizons intersect, we provide an exact solution of a cone that describes two intersecting horizons at different temperatures. Moreover, we show that this solution equally describes a thin and long black droplet.

  3. Landfill Leachate Toxicity Removal in Combined Treatment with Municipal Wastewater

    OpenAIRE

    Kalka, J.

    2012-01-01

    Combined treatment of landfill leachate and municipal wastewater was performed in order to investigate the changes of leachate toxicity during biological treatment. Three laboratory A2O lab-scale reactors were operating under the same parameters (Q-8.5–10 L/d; HRT-1.4–1.6 d; MLSS 1.6–2.5 g/L) except for the influent characteristic and load. The influent of reactor I consisted of municipal wastewater amended with leachate from postclosure landfill; influent of reactor II consisted of leachate ...

  4. Leachate migration and its impacts on the environment

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Y. S

    1998-12-01

    In Korea there are hundreds of landfill sites all over the peninsular and the leachate problem is one of the national concern. Heavy precipitation especially during hot summers creates the fast degradation of waste products in the site which accelerates the migration of the leachate. In this report current status of the landfill site related issues were studied along with potential solutions on them. Also the fundamental mathematical derivations to describe the movement of the leachate in geologic medium was studied. These results shall be used to assess the leachate migration in the specific landfill site in the 2nd R and D year.

  5. Generation of leachate and the flow regime in landfills

    Energy Technology Data Exchange (ETDEWEB)

    Bendz, D.

    1998-06-01

    In this thesis the generation of leachate and the presence and movement of water in landfilled municipal solid waste (MSW) is investigated. The precipitation-leachate discharge relationship for landfills was found to be dominated by evaporation, accumulation in the soil cover, accumulation in the solid waste and fast gravitational flow in a network of channels. The flow regime is governed by the heterogeneity of the internal geometry of the landfill, which is characterized by a discrete structure, significant horizontal stratification, structural voids, impermeable surfaces, and low capillarity. Also the boundary conditions, that is the water input pattern, has shown to be important for the flow process. Based on this, landfilled waste can be conceptualized as a dual domain medium, consisting of a channel domain and a matrix domain. The matrix flow is slow and diffusive, whereas the channel flow is assumed to be driven solely by gravity and to take place as a thin viscous film on solid surfaces. A kinematic wave model for unsaturated infiltration and internal drainage in the channel domain is presented. The model employs a two-parameter power expression as macroscopic flux law. Solutions were derived for the cases when water enters the channel domain laterally and when water enters from the upper end. The model parameters were determined and interpreted in terms of the internal geometry of the waste medium by fitting the model to one set of infiltration and drainage data derived from a large scale laboratory experiment under transient conditions. The model was validated using another set of data from a sequence of water input events and was shown to perform accurately. A solute transport model was developed by coupling a simple piston flux expression and a mobile-immobile conceptualization of the transport domains with the water flow model. Breakthrough curves derived from steady and transient tracer experiments where interpreted with the model. The transport

  6. Treating landfill leachate using passive aeration trickling filters; effects of leachate characteristics and temperature on rates and process dynamics.

    Science.gov (United States)

    Matthews, Richard; Winson, Michael; Scullion, John

    2009-04-01

    Biological ammoniacal-nitrogen (NH(4)(+)-N) and organic carbon (TOC) treatment was investigated in replicated mesoscale attached microbial film trickling filters, treating strong and weak strength landfill leachates in batch mode at temperatures of 3, 10, 15 and 30 degrees C. Comparing leachates, rates of NH(4)(+)-N reduction (0.126-0.159 g m(-2) d(-1)) were predominantly unaffected by leachate characteristics; there were significant differences in TOC rates (0.072-0.194 g m(-2) d(-1)) but no trend relating to leachate strength. Rates of total oxidised nitrogen (TON) accumulation (0.012-0.144 g m(-2) d(-1)) were slower for strong leachates. Comparing temperatures, treatment rates varied between 0.029-0.319 g NH(4)(+)-N m(-2) d(-1) and 0.033-0.251 g C m(-2) d(-1) generally increasing with rising temperatures; rates at 3 degrees C were 9 and 13% of those at 30 degrees C for NH(4)(+)-N and TOC respectively. For the weak leachates (NH(4)(+)-N<140 mg l(-1)) complete oxidation of NH(4)(+)-N was achieved. For the strong leachates (NH(4)(+)-N 883-1150 mg l(-1)) a biphasic treatment response resulted in NH(4)(+)-N removal efficiencies of between 68 and 88% and for one leachate no direct transformation of NH(4)(+)-N to TON in bulk leachate. The temporal decoupling of NH(4)(+)-N oxidation and TON accumulation in this leachate could not be fully explained by denitrification, volatilisation or anammox, suggesting temporary storage of N within the treatment system. This study demonstrates that passive aeration trickling filters can treat well-buffered high NH(4)(+)-N strength landfill leachates under a range of temperatures and that leachate strength has no effect on initial NH(4)(+)-N treatment rates. Whether this approach is a practicable option depends on a range of site specific factors.

  7. DOM composition and transformation in boreal forest soils: The effects of temperature and organic-horizon decomposition state

    Science.gov (United States)

    O'Donnell, Jonathan A.; Aiken, George R.; Butler, Kenna D.; Guillemette, Francois; Podgorski, David C.; Spencer, Robert G. M.

    2016-10-01

    The boreal region stores large amounts of organic carbon (C) in organic-soil horizons, which are vulnerable to destabilization via warming and disturbance. Decomposition of soil organic matter (SOM) contributes to the production and turnover of dissolved organic matter (DOM). While temperature is a primary control on rates of SOM and DOM cycling, little is known about temperature effects on DOM composition in soil leachate. Here we conducted a 30 day incubation to examine the effects of temperature (20 versus 5°C) and SOM decomposition state (moss versus fibric versus amorphous horizons) on DOM composition in organic soils of interior Alaska. We characterized DOM using bulk dissolved organic C (DOC) concentration, chemical fractionation, optical properties, and ultrahigh-resolution mass spectrometry. We observed an increase in DOC concentration and DOM aromaticity in the 20°C treatment compared to the 5°C treatment. Leachate from fibric horizons had higher DOC concentration than shallow moss or deep amorphous horizons. We also observed chemical shifts in DOM leachate over time, including increases in hydrophobic organic acids, polyphenols, and condensed aromatics and decreases in low-molecular weight hydrophilic compounds and aliphatics. We compared ultrahigh-resolution mass spectrometry and optical data and observed strong correlations between polyphenols, condensed aromatics, SUVA254, and humic-like fluorescence intensities. These findings suggest that biolabile DOM was preferentially mineralized, and the magnitude of this transformation was determined by kinetics (i.e., temperature) and substrate quality (i.e., soil horizon). With future warming, our findings indicate that organic soils may release higher concentrations of aromatic DOM to aquatic ecosystems.

  8. DOM composition and transformation in boreal forest soils: The effects of temperature and organic-horizon decomposition state

    Science.gov (United States)

    O’Donnell, Jonathan A.; Aiken, George R.; Butler, Kenna D.; Guillemette, Francois; Podgorski, David C.; Spencer, Robert G. M.

    2016-01-01

    The boreal region stores large amounts of organic carbon (C) in organic-soil horizons, which are vulnerable to destabilization via warming and disturbance. Decomposition of soil organic matter (SOM) contributes to the production and turnover of dissolved organic matter (DOM). While temperature is a primary control on rates of SOM and DOM cycling, little is known about temperature effects on DOM composition in soil leachate. Here we conducted a 30 day incubation to examine the effects of temperature (20 versus 5°C) and SOM decomposition state (moss versus fibric versus amorphous horizons) on DOM composition in organic soils of interior Alaska. We characterized DOM using bulk dissolved organic C (DOC) concentration, chemical fractionation, optical properties, and ultrahigh-resolution mass spectrometry. We observed an increase in DOC concentration and DOM aromaticity in the 20°C treatment compared to the 5°C treatment. Leachate from fibric horizons had higher DOC concentration than shallow moss or deep amorphous horizons. We also observed chemical shifts in DOM leachate over time, including increases in hydrophobic organic acids, polyphenols, and condensed aromatics and decreases in low-molecular weight hydrophilic compounds and aliphatics. We compared ultrahigh-resolution mass spectrometry and optical data and observed strong correlations between polyphenols, condensed aromatics, SUVA254, and humic-like fluorescence intensities. These findings suggest that biolabile DOM was preferentially mineralized, and the magnitude of this transformation was determined by kinetics (i.e., temperature) and substrate quality (i.e., soil horizon). With future warming, our findings indicate that organic soils may release higher concentrations of aromatic DOM to aquatic ecosystems.

  9. Spatial analysis of Mount St. Helens tephra leachate compositions: implications for future sampling strategies.

    Science.gov (United States)

    Ayris, P M; Delmelle, P; Pereira, B; Maters, E C; Damby, D E; Durant, A J; Dingwell, D B

    Tephra particles in physically and chemically evolving volcanic plumes and clouds carry soluble sulphate and halide salts to the Earth's surface, ultimately depositing volcanogenic compounds into terrestrial or aquatic environments. Upon leaching of tephra in water, these salts dissolve rapidly. Previous studies have investigated the spatial and temporal variability of tephra leachate compositions during an eruption in order to gain insight into the mechanisms of gas-tephra interaction which emplace those salts. However, the leachate datasets analysed are typically small and may poorly represent the natural variability and complexity of tephra deposits. Here, we have conducted a retrospective analysis of published leachate analyses from the 18 May 1980 eruption of Mount St. Helens, Washington, analysing the spatial structure of the concentrations and relative abundances of soluble Ca, Cl, Na and S across the deposits. We have identified two spatial features: (1) concentrated tephra leachate compositions in blast deposits to the north of the volcano and (2) low S/Cl and Na/Cl ratios around the Washington-Idaho border. By reference to the bulk chemistry and granulometry of the deposit and to current knowledge of gas-tephra interactions, we suggest that the proximal enrichments are the product of pre-eruptive gas uptake during cryptodome emplacement. We speculate that the low S/Cl and Na/Cl ratios reflect a combination of compositional dependences on high-temperature SO 2 uptake and preferential HCl uptake by hydrometeor-tephra aggregates, manifested in terrestrial deposits by tephra sedimentation and fallout patterns. However, despite our interrogation of the most exhaustive tephra leachate dataset available, it has become clear in this effort that more detailed insights into gas-tephra interaction mechanisms are prevented by the prevalent poor temporal and spatial representativeness of the collated data and the limited characterisation of the tephra deposits

  10. Spatial and temporal migration of a landfill leachate plume in alluvium

    Science.gov (United States)

    Masoner, Jason R.; Cozzarelli, Isabelle M.

    2015-01-01

    Leachate from unlined or leaky landfills can create groundwater contaminant plumes that last decades to centuries. Understanding the dynamics of leachate movement in space and time is essential for monitoring, planning and management, and assessment of risk to groundwater and surface-water resources. Over a 23.4-year period (1986–2010), the spatial extent of the Norman Landfill leachate plume increased at a rate of 7800 m2/year and expanded by 878 %, from an area of 20,800 m2 in 1986 to 203,400 m2 in 2010. A linear plume velocity of 40.2 m/year was calculated that compared favorably to a groundwater-seepage velocity of 55.2 m/year. Plume-scale hydraulic conductivity values representative of actual hydrogeological conditions in the alluvium ranged from 7.0 × 10−5 to 7.5 × 10−4 m/s, with a median of 2.0 × 10−4 m/s. Analyses of field-measured and calculated plume-scale hydraulic conductivity distributions indicate that the upper percentiles of field-measured values should be considered to assess rates of plume-scale migration, spreading, and biodegradation. A pattern of increasing Cl− concentrations during dry periods and decreasing Cl− concentrations during wet periods was observed in groundwater beneath the landfill. The opposite occurred in groundwater downgradient from the landfill; that is, Cl− concentrations in groundwater downgradient from the landfill decreased during dry periods and increased during wet periods. This pattern of changing Cl−concentrations in response to wet and dry periods indicates that the landfill retains or absorbs leachate during dry periods and produces lower concentrated leachate downgradient. During wet periods, the landfill receives more recharge which dilutes leachate in the landfill but increases leachate migration from the landfill and produces a more concentrated contaminant plume. This approach of quantifying plume expansion, migration, and concentration during variable hydrologic

  11. The effectiveness of leachate remediation in the implementation of unvegetated constructed wetland

    Science.gov (United States)

    Laily, Sophia; Retnaningdyah, Catur; Yanuwiadi, Bagyo

    2017-11-01

    The objective of this research was to examine the effectiveness of leachate remediation that is performed through the implementation of a free water surface (FWS) unvegetated constructed wetland system (UCW). The abovementioned remediation was conducted in a glass house with complete randomized design and using a small-scale UCW referred to as UCW reactor. The reactor was designed to replicate a large-scale FWS UCW and was filled with sand and gravel in a 3:5 ratio. The measurements of the leachate quality throughout the remediation experiment were based on hydraulic retention time (HRT) calculation and carried out on the 1st, 5th, 10th, 15th, 21th and 30th days. Subsequently, the resulted homogenous measurements were analyzed using One-way ANOVA while the non-homogenous ones were analyzed using the Brown-Forsythe test. For further analyses on the resulted statistical data, Turkey-HSD or Games Howell test and Euclidean-distance clustering and biplot were applied. The data representing value decreases in the physicochemical leachate parameters suggest the improvement of the leachate quality throughout the treatment. It was proven that FWS UCW is effective in reducing conductivity, total dissolved solids (TDS), nitrate and orthophosphate contents by 51.31%, 32.94%, 52.25% and 36.24%, respectively on the 5th day. On the 30th day, the leachate quality was further improved as the decreases of the four substances reached 79.64%, 56.28%, 80.58% and 90.39%, respectively.

  12. Leachate treatment system using constructed wetlands, Town of Fenton sanitary landfill, Broome County, New York. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    Municipal sanitary landfills generate leachate that New York State regulations require to be collected and treated to avoid contaminating surface water and groundwater. One option for treating leachate is to haul it to municipal wastewater treatment facility. This option may be expensive, may require excessive energy for transportation, and may require pretreatment to protect the receiving facility`s processes. An alternative is on-site treatment and discharge. Personnel from the Town of Fenton, New York; Hawk Engineering, P.C.; Cornell University; and Ithaca College designed, built, and operated a pilot constructed wetland for treating leachate at the Town of Fenton`s municipal landfill. The system, consisting of two overland flow beds and two subsurface flow beds has been effective for 18 months in reducing levels of ammonia (averaging 85% removal by volatilization and denitrification) and total iron (averaging 95% removal by precipitation and sedimentation), two key constituents of the Fenton landfill`s leachate. The system effects these reductions with zero chemical and energy inputs and minimal maintenance. A third key constituent of the leachate, manganese, apparently passes through the beds with minimal removal. Details and wetland considerations are described.

  13. Correlation between acute toxicity for Daphnia magna, Aliivibrio fischeri and physicochemical variables of the leachate produced in landfill simulator reactors.

    Science.gov (United States)

    Barrios Restrepo, José J; Flohr, Letícia; Melegari, Silvia P; da Costa, Cristina H; Fuzinatto, Cristiane F; de Castilhos, Armando B; Matias, William G

    2017-11-01

    Due to the diversified nature of municipal solid waste and the different stages of its decomposition, the formed leachates result in a complex chemical mixture with toxic potential. These chemicals can cause environmental problems, such as the contamination of surface or groundwater, thus affecting the balance of aquatic ecosystems. The aim of our study was to evaluate the acute toxicity of leachates in Daphnia magna and Aliivibrio fischeri and to identify the main physicochemical variables that influence the toxicity of the landfill leachates produced in reactors within pilot simulations. Acute toxicity tests carried out on D. magna and A. fischeri showed that the leachates produced inside the reactors are highly toxic, presenting EC50 48h  magna and EC50 15min  < 12% for A. fischeri. This result indicates that microcrustaceans are more sensitive to leachates, making them more suitable to our study. Pb showed the highest correlation with EC50 48h , suggesting that Pb is the main chemical variable indicative of toxicity for the conditions of the experiment. In smaller scale, phosphate (PO 4 3- ) and nitrate (NO 3- ) were the macronutrients that most influenced the toxicity. Clearly, this correlation should be viewed with caution because the synergistic effects of this complex mixture are difficult to observe.

  14. Social Pharmacology: Expanding horizons

    Science.gov (United States)

    Maiti, Rituparna; Alloza, José Luis

    2014-01-01

    In the current modern and global society, social changes are in constant evolution due to scientific progress (technology, culture, customs, and hygiene) and produce the freedom in individuals to take decisions by themselves or with their doctors toward drug consumption. In the arena of marketed drug products which includes society, individual, administration, and pharmaceutical industry, the young discipline emerged is social pharmacology or sociopharmacology. This science arises from clinical pharmacology, and deals with different parameters, which are important in creating knowledge on marketed drugs. However, the scope of “social pharmacology” is not covered by the so-called “Phase IV” alone, but it is the science that handles the postmarketing knowledge of drugs. The social pharmacology studies the “life cycle” of any marketed pharmaceutical product in the social terrain, and evaluates the effects of the real environment under circumstances totally different in the drug development process. Therefore, there are far-reaching horizons, plural, and shared predictions among health professionals and other, for beneficial use of a drug, toward maximizing the benefits of therapy, while minimizing negative social consequences. PMID:24987168

  15. Three theorems on near horizon extremal vanishing horizon geometries

    Directory of Open Access Journals (Sweden)

    S. Sadeghian

    2016-02-01

    Full Text Available EVH black holes are Extremal black holes with Vanishing Horizon area, where vanishing of horizon area is a result of having a vanishing one-cycle on the horizon. We prove three theorems regarding near horizon geometry of EVH black hole solutions to generic Einstein gravity theories in diverse dimensions. These generic gravity theories are Einstein–Maxwell-dilaton-Λ theories, and gauged or ungauged supergravity theories with U(1 Maxwell fields. Our three theorems are: (1 The near horizon geometry of any EVH black hole has a three dimensional maximally symmetric subspace. (2 If the energy momentum tensor of the theory satisfies strong energy condition either this 3d part is an AdS3, or the solution is a direct product of a locally 3d flat space and a d−3 dimensional part. (3 These results extend to the near horizon geometry of near-EVH black holes, for which the AdS3 part is replaced with BTZ geometry.

  16. Assessment of groundwater contamination by leachate near a ...

    African Journals Online (AJOL)

    Physico-chemical and microbiological parameters were analyzed in leachate and groundwater samples obtained at different locations adjacent to a municipal solid waste landfill in order to assess the impact of leachate percolation on groundwater quality. Total dissolved solids (TDS), electrical conductivity (EC), and Na+ ...

  17. Groundwater and Leachate Monitoring and Sampling at ERDF, CY 2009

    Energy Technology Data Exchange (ETDEWEB)

    R.L. Weiss, B.L. Lawrence, D.W. Woolery

    2010-07-08

    This document reports the findings of the groundwater and leachate monitoring and sampling at the Environmental restoration Disposal Facility for calendar year 2009. The purpose of this annual monitoring report is to evaluate the conditions of and identify trends for groundwater beneath the ERDF and report leachate results in fulfillment of the requirements specified in the ERDF ROD and the ERDF Amended ROD.

  18. Levels of some physiochemical parameters in leachates from open ...

    African Journals Online (AJOL)

    Leachates from selected dumpsites and control site in Lokoja municipal were analyzed for physiochemical properties. These parameters were compared with control samples and established international standards FEPA and WHO. Dumpsite leachates contained very high concentration of TDS which ranges between ...

  19. Fortran algorithm for monitoring Leachates and interpreting physico ...

    African Journals Online (AJOL)

    Fortran algorithm for monitoring Leachates and interpreting physico-chemical data of contaminants in ground water. ... Journal of Applied Science and Technology ... A FOTRAN 90 algorithm was developed to interpret leachate geochemical data of polluted ground water in Lagos, based on 19 selected physico-chemical ...

  20. Adsorption of heavy metal from landfill leachate by wasted biosolids ...

    African Journals Online (AJOL)

    However, the concentration of Cd, Cu and Zn was not detected in the leachate but Fe was found to be in high concentration (184 mg/L) in raw leachate collected from a municipal landfill site. Therefore, the effects of biomass dosage, contact time, pH and agitation speed were observed for optimal adsorption of iron from ...

  1. The Effects of Leachate on Groundwater in Ota Industrial Area ...

    African Journals Online (AJOL)

    Compositions of landfill leachate and groundwater pollution were studied at industrial sites landfill, which are located at Ota, Nigeria. The leachate was sampled at 5 different locations at the landfill, and at 15 and 20 m downstream of the landfill. Groundwater samples were collected from 10 different sources to study the ...

  2. Genotoxicity and mutagenicity of solid waste leachates: A review ...

    African Journals Online (AJOL)

    Leachate, generated due to the infiltration of water/precipitation through the waste mass and the wastes biodegradation, is a mixture of dissolved organic matter, inorganic macro-components, heavy metals, xenobiotic organic compounds and microorganisms. Several studies have reported the acute toxicity of leachate ...

  3. Leachate characterization of active and closed dump sites in Port ...

    African Journals Online (AJOL)

    This study characterizes the leachate quality of both active and closed dump sites in Port Harcourt City. Leachates were sampled from the base of the dum psites and analysed, pH, dissolved oxygen (DO), electrical conductivity and total dissolved solids were determined on the samples in-situ. While chloride, sulphate ...

  4. Uptake of Cd, Cu, Ni and Zn by the water hyacinth, Eichhornia crassipes (mart.) solms from pulverised fuel ash (PFA) leachates and slurries

    Energy Technology Data Exchange (ETDEWEB)

    Cordes, K.B.; Mehra, A.; Farago, M.E.; Banerjee, D.K. [University of Derby, Derby (United Kingdom). School of Environmental and Applied Science

    2000-12-01

    The main solid waste product from coal-fired power stations is pulverised fuel ash (PFA). This study investigates the uptake of Cd, Cu, Ni and Zn by the aquatic plant E-crassipes grown in leachates and slurries prepared from two different PFA samples. PFA samples were obtained from Indraprastha Power Station (IPP stn.) in New Delhi, India and the Ratcliffe-on-Soar Power Station in the UK. Results show that E. crassipes has a high accumulation capacity for Cd, Cu, Ni and Zn from leachates and slurries generated from two different PFAs and uptake of these metals is stronger in the roots than in the tops of the plant. As the metal concentrations in the growth medium increase in the 1:5 PFA:DIW ratio as compared to the 1:50 ratio, metal accumulation (as indicated by accumulation factor (AF) values) from both leachates and slurries is higher for plants grown in the 1:50 (PFA:DIW) ratios than in the 1:5 ratios. Lower metal accumulation in the plants grown in slurries than in leachates is related to the high turbidity of growth medium in slurries resulting in ash particles adhering to the root surfaces thus reducing the surface area of metal absorption. In terms of neutralisation capacity of the pH of the growth medium, Eichhornia is seen to be able to reduce the pH of all leachates. Accumulation of Cd and Zn by the plant is higher from the lower pH IPP leachates than the Ratcliffe leachates, indicating that these metals are more soluble and bioavailable in the acidic medium. Accumulation of Cu and Ni is independent of the pH of the leachates; indicating that there may be other contributory factors. 78 refs., 7 tabs.

  5. New horizons in osteoarthritis.

    Science.gov (United States)

    Oliviero, F; Ramonda, R; Punzi, L

    2010-09-17

    Osteoarthritis (OA), also known as degenerative joint disease, is the most frequent chronic musculoskeletal disease and the leading cause of disability in elderly persons. There are currently at least 27 million persons afflicted with OA in the United States, and the annual cost to society in medical care and wage loss is expected to reach nearly $100 billion dollars by 2020, with consequent increased spending on its diagnosis and treatment, side effect prevention, and loss of productivity. Despite this enormous burden, many aspects of OA are still unknown, with implications not only in terms of diagnosis and assessment but also with regard to therapy. Awareness of this state of affairs has attracted many researchers to this field, making OA one of the most actively studied sectors of rheumatology. Although some clinicians are unaware of recent advances, there is a large body of publications indicating that much has been achieved. Major progress has been made in formulating better definitions of risk factors, in particular in indicating the responsibility of biomechanical and genetic factors, and, with regard to pathogenesis, underlining the role of subchondral bone, cytokines and proteinases. Assessment of OA activity and its progression has been improved with the advent of biomarkers and new imaging procedures, in particular sonography and magnetic resonance imaging (MRI), but also of better clinical instruments, including more reliable patient questionnaires. Information from ongoing studies may improve the to some extent incomplete definition of OA phenotypes. Finally, promising new horizons have been opened up even with regard to the treatment of OA, which is still for the most part unsatisfactory except for surgical replacement therapy. Numerous new substances have been formulated and the findings of trials studying their effects are encouraging, although much has yet to be done.

  6. LCA and economic evaluation of landfill leachate and gas technologies

    DEFF Research Database (Denmark)

    Damgaard, Anders; Manfredi, Simone; Merrild, Hanna Kristina

    2011-01-01

    Landfills receiving a mix of waste, including organics, have developed dramatically over the last 3–4 decades; from open dumps to engineered facilities with extensive controls on leachate and gas. The conventional municipal landfill will in most climates produce a highly contaminated leachate......-effective in reducing the impact from a conventional landfill. This was done by modeling landfills ranging from a simple open dump to highly engineered conventional landfills with energy recovery in form of heat or electricity. The modeling was done in the waste LCA model EASEWASTE. The results showed drastic...... leachate is collected. However, at the same time, leachate collection causes a slight increase in eco-toxicity and human toxicity via water (0.007E to 0.013PE and 0.002 to 0.003 PE respectively). The reason for this is that even if the leachate is treated, slight amounts of contaminants are released...

  7. Effects of Toxic Leachate from Commercial Plastics on Larval Survival and Settlement of the Barnacle Amphibalanus amphitrite.

    Science.gov (United States)

    Li, Heng-Xiang; Getzinger, Gordon J; Ferguson, P Lee; Orihuela, Beatriz; Zhu, Mei; Rittschof, Daniel

    2016-01-19

    Plastic pollution represents a major and growing global problem. It is well-known that plastics are a source of chemical contaminants to the aquatic environment and provide novel habitats for marine organisms. The present study quantified the impacts of plastic leachates from the seven categories of recyclable plastics on larval survival and settlement of barnacle Amphibalanus (=Balanus) amphitrite. Leachates from plastics significantly increased barnacle nauplii mortality at the highest tested concentrations (0.10 and 0.50 m(2)/L). Hydrophobicity (measured as surface energy) was positively correlated with mortality indicating that plastic surface chemistry may be an important factor in the effects of plastics on sessile organisms. Plastic leachates significantly inhibited barnacle cyprids settlement on glass at all tested concentrations. Settlement on plastic surfaces was significantly inhibited after 24 and 48 h, but settlement was not significantly inhibited compared to the controls for some plastics after 72-96 h. In 24 h exposure to seawater, we found larval toxicity and inhibition of settlement with all seven categories of recyclable commercial plastics. Chemical analysis revealed a complex mixture of substances released in plastic leachates. Leaching of toxic compounds from all plastics should be considered when assessing the risks of plastic pollution.

  8. Advanced landfill leachate treatment using iron-carbon microelectrolysis- Fenton process: Process optimization and column experiments

    International Nuclear Information System (INIS)

    Wang, Liqun; Yang, Qi; Wang, Dongbo; Li, Xiaoming; Zeng, Guangming; Li, Zhijun; Deng, Yongchao; Liu, Jun; Yi, Kaixin

    2016-01-01

    Highlights: • Fe-C microelectrolysis-Fenton process is proposed to pretreat landfill leachate. • Operating variables are optimized by response surface methodology (RSM). • 3D-EEMs and MW distribution explain the mechanism of enhanced biodegradability. • Fixed-bed column experiments are performed at different flow rates. - Abstract: A novel hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor was proposed for the pretreatment of mature landfill leachate. This reactor, combining microelectrolysis with Fenton process, revealed high treatment efficiency. The operating variables, including Fe-C dosage, H 2 O 2 concentration and initial pH, were optimized by the response surface methodology (RSM), regarding the chemical oxygen demand (COD) removal efficiency and biochemical oxygen demand: chemical oxygen demand (BOD 5 /COD) as the responses. The highest COD removal (74.59%) and BOD 5 /COD (0.50) was obtained at optimal conditions of Fe-C dosage 55.72 g/L, H 2 O 2 concentration 12.32 mL/L and initial pH 3.12. Three-dimensional excitation and emission matrix (3D-EEM) fluorescence spectroscopy and molecular weight (MW) distribution demonstrated that high molecular weight fractions such as refractory fulvic-like substances in leachate were effectively destroyed during the combined processes, which should be attributed to the combination oxidative effect of microelectrolysis and Fenton. The fixed-bed column experiments were performed and the breakthrough curves at different flow rates were evaluated to determine the practical applicability of the combined process. All these results show that the hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor is a promising and efficient technology for the treatment of mature landfill leachate.

  9. Advanced landfill leachate treatment using iron-carbon microelectrolysis- Fenton process: Process optimization and column experiments

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Liqun, E-mail: 691127317@qq.com [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Yang, Qi, E-mail: yangqi@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Wang, Dongbo [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Li, Xiaoming, E-mail: xmli121x@hotmail.com [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Zeng, Guangming; Li, Zhijun; Deng, Yongchao; Liu, Jun; Yi, Kaixin [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China)

    2016-11-15

    Highlights: • Fe-C microelectrolysis-Fenton process is proposed to pretreat landfill leachate. • Operating variables are optimized by response surface methodology (RSM). • 3D-EEMs and MW distribution explain the mechanism of enhanced biodegradability. • Fixed-bed column experiments are performed at different flow rates. - Abstract: A novel hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor was proposed for the pretreatment of mature landfill leachate. This reactor, combining microelectrolysis with Fenton process, revealed high treatment efficiency. The operating variables, including Fe-C dosage, H{sub 2}O{sub 2} concentration and initial pH, were optimized by the response surface methodology (RSM), regarding the chemical oxygen demand (COD) removal efficiency and biochemical oxygen demand: chemical oxygen demand (BOD{sub 5}/COD) as the responses. The highest COD removal (74.59%) and BOD{sub 5}/COD (0.50) was obtained at optimal conditions of Fe-C dosage 55.72 g/L, H{sub 2}O{sub 2} concentration 12.32 mL/L and initial pH 3.12. Three-dimensional excitation and emission matrix (3D-EEM) fluorescence spectroscopy and molecular weight (MW) distribution demonstrated that high molecular weight fractions such as refractory fulvic-like substances in leachate were effectively destroyed during the combined processes, which should be attributed to the combination oxidative effect of microelectrolysis and Fenton. The fixed-bed column experiments were performed and the breakthrough curves at different flow rates were evaluated to determine the practical applicability of the combined process. All these results show that the hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor is a promising and efficient technology for the treatment of mature landfill leachate.

  10. Entropy bound of horizons for accelerating, rotating and charged Plebanski–Demianski black hole

    International Nuclear Information System (INIS)

    Debnath, Ujjal

    2016-01-01

    We first review the accelerating, rotating and charged Plebanski–Demianski (PD) black hole, which includes the Kerr–Newman rotating black hole and the Taub-NUT spacetime. The main feature of this black hole is that it has 4 horizons like event horizon, Cauchy horizon and two accelerating horizons. In the non-extremal case, the surface area, entropy, surface gravity, temperature, angular velocity, Komar energy and irreducible mass on the event horizon and Cauchy horizon are presented for PD black hole. The entropy product, temperature product, Komar energy product and irreducible mass product have been found for event horizon and Cauchy horizon. Also their sums are found for both horizons. All these relations are dependent on the mass of the PD black hole and other parameters. So all the products are not universal for PD black hole. The entropy and area bounds for two horizons have been investigated. Also we found the Christodoulou–Ruffini mass for extremal PD black hole. Finally, using first law of thermodynamics, we also found the Smarr relation for PD black hole.

  11. A comparison of landfill leachates based on waste composition.

    Science.gov (United States)

    Moody, Chris M; Townsend, Timothy G

    2017-05-01

    Samples of leachate were collected from fourteen landfills in the state of Florida, United States that contained primarily putrescible waste (municipal solid waste, MSW, and yard waste), MSW incinerator (MSWI) ash, or a combination of both. Assessment of leachates included trace metals, anions, and nutrients in order to create a mass balance of total dissolved solids (TDS). As expected from previously literature, MSW leached a complex matrix of contaminants while MSWI ash leachate TDS was more than 98% metallic salts. The pH of the MSWI ash leachate samples was slightly acidic or neutral in character, which is contradictory to the results commonly reported in the literature. The cause of this is hypothesized to be a short-circuiting of rainfall in the landfill due to low hydraulic conductivities reported in ash landfills. The difference in pH likely contributed to the findings with respect to MSWI ash-characteristic trace metals in leachates such as aluminum. The authors have concluded that the research findings in this study are an indication of the differences between laboratory leachate quality studies and the conditions encountered in the field. In addition, a characterization of organic matter using qualitative and quantitative analyses determined that COD is not an accurate indicator of organic matter in leachates from landfills with a significant fraction of MSWI ash. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Use of ammoniacal nitrogen tolerant microalgae in landfill leachate treatment.

    Science.gov (United States)

    Lin, L; Chan, G Y S; Jiang, B L; Lan, C Y

    2007-01-01

    Two microalgae, Chlorella pyrenoidosa and Chlamydomonas snowiae, were isolated from a high ammonia leachate pond in Li Keng Landfill, Guangzhou, China. Their growth and nutrient removal rates were determined in a serial dilution of landfill leachate under laboratory conditions, and their growth rates were compared with that of a C. pyrenoidosa strain isolated from a clean river. The results indicated the growth of all three algae was inhibited by high leachate concentrations, and the inhibition appears linked to high ammonia (ammoniacal-N670mgL(-1)). Significant amounts of ammoniacal-N, ortho-P and COD in the leachate were removed by the algae, with a positive correlation between algal growth and nutrient consumption. Not enough data are available to conclude that one strain was less inhibited by ammoniacal nitrogen or more effective at treating it. Phytotoxicity of leachate was reduced after algal growth, as demonstrated by a seed germination experiment with Brassica chinensis. The germination rates in 10%, 30% and 50% concentrations of algal-treated leachate were significantly higher than those in the same concentration but algal-free leachate.

  13. Natural attenuation, biostimulation and bioaugmentation of landfill leachate management

    Science.gov (United States)

    Er, X. Y.; Seow, T. W.; Lim, C. K.; Ibrahim, Z.

    2018-04-01

    Landfills used for solid waste management will lead to leachate production. Proper leachate management is highly essential to be paid attention to protect the environment and living organisms’ health and safety. In this study, the remedial strategies used for leachate management were natural attenuation, biostimulation and bioaugmentation. All treatment samples were treated via 42-days combined anaerobic-aerobic treatment and the treatment efficiency was studied by measuring the removal rate of COD and ammonia nitrogen. In this study, all remedial strategies showed different degrees of contaminants removal. Lowest contaminants removal rate was achieved via bioaugmentation of B. panacihumi strain ZB1, which were 39.4% of COD and 37.6% of ammonia nitrogen removed from the leachate sample. Higher contaminants removal rate was achieved via natural attenuation and biostimulation. Native microbial population was able to remove 41% of COD and 59% of ammonia nitrogen from the leachate sample. The removal efficiency could be further improved via biostimulation to trigger microbial growth and decontamination rate. Through biostimulation, 58% of COD and 51.8% of ammonia nitrogen were removed from the leachate sample. In conclusion, natural attenuation and biostimulation should be the main choice for leachate management to avoid any unexpected impacts due to introduction of exogenous species.

  14. Composition of leachate from old landfills in Denmark

    DEFF Research Database (Denmark)

    Kjeldsen, Peter; Christophersen, Mette

    2001-01-01

    The Danish counties have performed numerous investigations of old landfills. These investigations have been presented in several reports, but no comprehensive summary of the findings has been carried out. The objective of this study was to evaluate the typical composition of leachates from old...... smaller landfills by a comprehensive review of the investigations carried out by the counties. In total 106 landfills were selected by criteria avoiding dilution effects. A database was constructed using a standard program. Statistical evaluations showed that the leachate concentrations in general...... decreased with the age of the landfill, and that the leachate concentrations were lower than found in other similar studies....

  15. Moving Horizon Estimation and Control

    DEFF Research Database (Denmark)

    Jørgensen, John Bagterp

    successful and applied methodology beyond PID-control for control of industrial processes. The main contribution of this thesis is introduction and definition of the extended linear quadratic optimal control problem for solution of numerical problems arising in moving horizon estimation and control...... problems. Chapter 1 motivates moving horizon estimation and control as a paradigm for control of industrial processes. It introduces the extended linear quadratic control problem and discusses its central role in moving horizon estimation and control. Introduction, application and efficient solution....... It provides an algorithm for computation of the maximal output admissible set for linear model predictive control. Appendix D provides results concerning linear regression. Appendix E discuss prediction error methods for identification of linear models tailored for model predictive control....

  16. An Autopsy of Nanofiltration Membrane Used for Landfill Leachate Treatment

    Directory of Open Access Journals (Sweden)

    Ibrahim Demir

    2015-01-01

    Full Text Available Komurcuoda leachate treatment plant, Istanbul, which consists of membrane bioreactor (MBR and nanofiltration (NF system, faced rapid flux decline in membranes after 3-year successful operation. To compensate rapid flux decline in membranes, the fouled membranes were renewed but replacement of the membranes did not solve the problem. To find the reasons and make a comprehensive analysis, membrane autopsy was performed. Visual and physical inspection of the modules and some instrumental analysis were conducted for membrane autopsy. Membranes were found severely fouled with organic and inorganic foulants. Main foulant was iron which was deposited on surface. The main reason was found to be the changing of aerator type of MBR. When surface aerators were exchanged with bottom diffusers which led to increasing of dissolved oxygen (DO level of the basin, iron particles were oxidized and they converted into particulate insoluble form. It was thought that probably this insoluble form of the iron particles was the main cause of decreased membrane performance. After the diagnosis, a new pretreatment alternative including a new iron antiscalant was suggested and system performance has been recovered.

  17. Advanced landfill leachate treatment using iron-carbon microelectrolysis- Fenton process: Process optimization and column experiments.

    Science.gov (United States)

    Wang, Liqun; Yang, Qi; Wang, Dongbo; Li, Xiaoming; Zeng, Guangming; Li, Zhijun; Deng, Yongchao; Liu, Jun; Yi, Kaixin

    2016-11-15

    A novel hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor was proposed for the pretreatment of mature landfill leachate. This reactor, combining microelectrolysis with Fenton process, revealed high treatment efficiency. The operating variables, including Fe-C dosage, H2O2 concentration and initial pH, were optimized by the response surface methodology (RSM), regarding the chemical oxygen demand (COD) removal efficiency and biochemical oxygen demand: chemical oxygen demand (BOD5/COD) as the responses. The highest COD removal (74.59%) and BOD5/COD (0.50) was obtained at optimal conditions of Fe-C dosage 55.72g/L, H2O2 concentration 12.32mL/L and initial pH 3.12. Three-dimensional excitation and emission matrix (3D-EEM) fluorescence spectroscopy and molecular weight (MW) distribution demonstrated that high molecular weight fractions such as refractory fulvic-like substances in leachate were effectively destroyed during the combined processes, which should be attributed to the combination oxidative effect of microelectrolysis and Fenton. The fixed-bed column experiments were performed and the breakthrough curves at different flow rates were evaluated to determine the practical applicability of the combined process. All these results show that the hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor is a promising and efficient technology for the treatment of mature landfill leachate. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Electrical-conductivity measurements of leachates for the rapid assessment of wasteform corrosion resistance

    International Nuclear Information System (INIS)

    Sales, B.C.; Petek, M.; Boatner, L.A.

    1982-01-01

    Measurements of the electrical conductivity of leachate solutions as a function of time can be used as an efficient, informative means of evaluation and comparison in the development of nuclear waste forms and in the preliminary analysis of their corrosion resistance in distilled water. Three separate applications of this technique are described in this work. These are: (1) its use in the optimization of the corrosion resistance of a crystalline wasteform (monazite); (2) a study of the protective ability of the surface layer (gel layer) which forms on the nuclear waste glass Frit 21 + 20 wt % SRW in distilled water; and (3) making comparisons of the overall corrosion resistance of three different nuclear wasteforms (i.e., monazite, SYNROC, and borosilicate glass). A complete solution analysis of the borosilicate glass leachate and a straightforward analysis of the conductivity results agree to within +-20%. In the absence of a complete, time consuming solution analysis, conductivity measurements can be used to estimate reliably the total ionic concentration in the leachate to within a factor of 2

  19. Temporal and spatial pore water pressure distribution surrounding a vertical landfill leachate recirculation well.

    Science.gov (United States)

    Kadambala, Ravi; Townsend, Timothy G; Jain, Pradeep; Singh, Karamjit

    2011-05-01

    Addition of liquids into landfilled waste can result in an increase in pore water pressure, and this in turn may increase concerns with respect to geotechnical stability of the landfilled waste mass. While the impact of vertical well leachate recirculation on landfill pore water pressures has been mathematically modeled, measurements of these systems in operating landfills have not been reported. Pressure readings from vibrating wire piezometers placed in the waste surrounding a liquids addition well at a full-scale operating landfill in Florida were recorded over a 2-year period. Prior to the addition of liquids, measured pore pressures were found to increase with landfill depth, an indication of gas pressure increase and decreasing waste permeability with depth. When liquid addition commenced, piezometers located closer to either the leachate injection well or the landfill surface responded more rapidly to leachate addition relative to those far from the well and those at deeper locations. After liquid addition stopped, measured pore pressures did not immediately drop, but slowly decreased with time. Despite the large pressures present at the bottom of the liquid addition well, much smaller pressures were measured in the surrounding waste. The spatial variation of the pressures recorded in this study suggests that waste permeability is anisotropic and decreases with depth.

  20. Pine-derived Biochar as Option for Adsorption of Сu, Zn, Cr, Pb, Ni and Decreasing of BOD5 in Landfill Leachate

    Directory of Open Access Journals (Sweden)

    Valeriia Chemerys

    2017-09-01

    Full Text Available Landfill leachate is a highly toxic and hazardous form of wastewater due to its complex composition characteristics, e.g. ammonia, metals, organic compounds. Landfill leachate treatment technologies, such as flotation, coagulation/flocculation, precipitation, oxidation, micro-, ultra-, nanofiltration, reverse osmosis, are too expensive, because they require frequent regeneration of the media or generate secondary brine wastes that may pose a disposal problem. In the present study removal of Zn, Ni, Cr, Pb, Cu from Kazokiškės landfill leachate was studied. Kazokiškės landfill is the main site for disposal of Vilnius region municipal wastes. Operator of the landfill is interested in the alternative ways for the primary treatment of the landfill leachate for reducing the load on the expensive reverse osmosis. One of the proposed options for the primary landfill leachate treatment was adsorption by biochar. Due to the high specific surface area, well-developed porous structure and surface functionality biochar has been used as low-cost adsorbent for adsorption of PTEs from aqueous solutions. Biochar was produced from Scots pine (Pinus sylvestris L. trunk wood (after debarking by pyrolysis at the highest heating temperature of 700 °C for 45 min in the low-oxygen environment. Laboratory analysis showed that PTEs, such as Zn, Ni, Cr, Pb, Cu, were present in the landfill leachate before water treatment plant. Thus, the aim of the study was to evaluate PTEs (Zn, Ni, Cr, Pb, Cu removal efficiency by adsorption by pine-derived biochar. Factors, affecting adsorption efficiency, such as biochar particle size (1, 2.5, 4, 5 mm and dosage of the biochar (1.01, 3.5, 6.05, 9.45, 13.25, 17.82 g/100 ml of leachate were studied. Effects of the biochar on pH of the landfill leachate, BOD5, PTEs adsorption were analyzed. The findings showed that optimal parameters for decreasing of BOD5 and retention of Cr and Pb were particle size 1 mm and dosage 6.05 g/100 ml

  1. CONJUGATE TREATMENT OF LEACHATE FROM LANDFILL AND SEWAGE IN DOMESTIC STABILIZATION PONDS

    Directory of Open Access Journals (Sweden)

    Valderi Duarte Leite

    2016-01-01

    Full Text Available In Brazil, the per capita generation of municipal solid waste is approximately 0.80 kg hab-1 day-1, which implies daily production of 156 tons, whereas on average 50% of this quantity of waste is composed mainly of putrescible organic material that will contribute to the leachate generation process directly influencing the qualitative and quantitative aspects. Landfill leachate basically originates from the percolation process of different types of water and is considered a wastewater to cause in significant environmental impact on the environment, given in possession of high concentration of ammonia nitrogen, organic matter difficult to biodegradation, metals heavy and xenobiotics. The objective of this study was to evaluate the performance of a series of stabilization ponds, the treatment process conjugate of landfill leachate fresh more domestic sewage in the proportion of 1 plus 99% (volume percent, respectively. The experimental system consisted of four stabilization ponds in series, being a facultative pond, followed by three maturation ponds. . The applied surface charge (λs the series of stabilization ponds was 320 kg DBO5 ha-1 day-1 with hydraulic retention time (HRT of 17 days for the series. The average removal efficiency of BOD5 and ammonia was 69 and 86% respectively, while removing coliform efficiency always in the 99.9% threshold during the monitoring period was 220 days. Overall it can be concluded that treatment conjugate landfill leachate and sewage in stabilization ponds, in northeastern Brazil, is emerging as a promising technological alternative, given the comfortable area availability in northeastern Brazil, conditions climate favorable and the ponds system present low ratio cost / benefit when compared to other waste treatment systems of this nature.

  2. Domestic Solid Waste Landfills: Experimental Analysis of Leachate Stripping Technique

    Science.gov (United States)

    Chistyakov, N. E.; Strelkov, A. K.; Teplykh, S. Y.

    2017-11-01

    The domestic solid waste (DSW) landfills activity is based on the natural processes of organic substances decomposition through their processing into other substances by micro-organisms. Such micro-organisms can only live in water or, in other words, they exist only in the aquatic environment, both in natural environment and under artificial conditions, e.g. in DSW landfill sites. This paper investigates the problem of DSW landfills leachate preparation for the reuse as irrigation water. Leachate is formed as an inescapable side-product of DSW landfills operation. Leachate is a result of precipitations and artificial irrigation contaminated by substances of microbiological decomposition and destruction of organic substances coming to landfill sites as domestic solid waste. The use of leachate as irrigation water will significantly change the DSW decomposition technology and the safety of landfill sites operations.

  3. Groundwater and Leachate Monitoring and Sampling at ERDF, CY 2008

    Energy Technology Data Exchange (ETDEWEB)

    R. L. Weiss; D. W. Woolery

    2009-09-03

    The purpose of this annual monitoring report is to evaluate the conditions of and identify trends for groundwater beneath the ERDF, to report leachate results in fulfillment of the requirements specified in the ERDF ROD and the ERDF Amended ROD.

  4. Groundwater and Leachate Monitoring and Sampling at ERDF, CY 2006

    Energy Technology Data Exchange (ETDEWEB)

    R. L. Weiss

    2007-05-30

    The purpose of this annual monitoring report is to evaluate the conditions of and identify trends for groundwater beneath the ERDF and to report leachate results in fulfillment of the requirements specified in the ERDF ROD.

  5. Groundwater and Leachate Monitoring and Sampling at ERDF, CY 2006

    Energy Technology Data Exchange (ETDEWEB)

    R. L. Weiss

    2007-12-05

    The purpose of this annual monitoring report is to evaluate the conditions of and identify trends for groundwater beneath the ERDF and to report leachate results in fulfillment of the requirements specified in the ERDF ROD.

  6. Adsorption of heavy metal from landfill leachate by wasted biosolids

    African Journals Online (AJOL)

    GREGORY

    2011-12-16

    Phanerochaete chrysosporium) was studied to remove cadmium, copper, zinc and iron from synthetic water and leachate. The biomass was produced due to the experiments conducted for bioconversion of wastewater for lignin ...

  7. New Horizons Mission to Pluto

    Science.gov (United States)

    Delgado, Luis G.

    2011-01-01

    This slide presentation reviews the trajectory that will take the New Horizons Mission to Pluto. Included are photographs of the spacecraft, the launch vehicle, the assembled vehicle as it is being moved to the launch pad and the launch. Also shown are diagrams of the assembled parts with identifying part names.

  8. Wave Height and Horizon Dip

    NARCIS (Netherlands)

    Van Der Werf, Siebren; Shokaryev, Igor

    2015-01-01

    A mariner who takes the height of the sun or a star to find his position at sea, must correct his observation for horizon dip. Throughout history, dip values have been tabulated based on the idealized assumption of a perfectly flat sea. Literature on wave height correction for dip is scarce,

  9. Nitrous oxide flux from landfill leachate-sawdust nitrogenous compost

    International Nuclear Information System (INIS)

    Hui, C.H.; So, M.K.; Lee, C.M.; Chan, G.Y.S.

    2003-01-01

    Composted nitrogenous waste has the potential to produce excessive amounts of nitrous oxide (N 2 O), a potent greenhouse gas that also contributes to stratospheric ozone depletion. In this laboratory study, sawdust was irrigated with varying amounts of landfill leachate with high NH 4 + -N content (3950 mg l -1 ). Physicochemical properties, including the amount of N 2 O produced, were monitored during the composting process over 28 days. A rapid decline in NH 4 + -N in the first 4 days and increasing NO 3 - -N for 11 days was followed by lower but stabilized levels of available-N, even with repeated leachate irrigation. Less than 0.03% of the leachate-applied N was lost as N 2 O. Higher leachate applications as much as tripled N 2 O production, but this represented a lesser proportion overall of the total nitrogen. Addition of glucose to the composting process had no significant effect on N 2 O production. The derived sawdust-leachate compost supported healthy growth of Sesbania rostrata. It is concluded that compost can be produced from sawdust irrigated with landfill leachate without substantial emission of N 2 O, although excessive flux of N 2 O remains about high application rates over longer time periods. (Author)

  10. Landfill Leachate Toxicity Removal in Combined Treatment with Municipal Wastewater

    Directory of Open Access Journals (Sweden)

    J. Kalka

    2012-01-01

    Full Text Available Combined treatment of landfill leachate and municipal wastewater was performed in order to investigate the changes of leachate toxicity during biological treatment. Three laboratory A2O lab-scale reactors were operating under the same parameters (Q-8.5–10 L/d; HRT-1.4–1.6 d; MLSS 1.6–2.5 g/L except for the influent characteristic and load. The influent of reactor I consisted of municipal wastewater amended with leachate from postclosure landfill; influent of reactor II consisted of leachate collected from transient landfill and municipal wastewater; reactor III served as a control and its influent consisted of municipal wastewater only. Toxicity of raw and treated wastewater was determinted by four acute toxicity tests with Daphnia magna, Thamnocephalus platyurus, Vibrio fischeri, and Raphidocelis subcapitata. Landfill leachate increased initial toxicity of wastewater. During biological treatment, significant decline of acute toxicity was observed, but still mixture of leachate and wastewater was harmful to all tested organisms.

  11. Biogeochemistry at a wetland sediment-alluvial aquifer interface in a landfill leachate plume

    Science.gov (United States)

    Lorah, M.M.; Cozzarelli, I.M.; Böhlke, J.K.

    2009-01-01

    The biogeochemistry at the interface between sediments in a seasonally ponded wetland (slough) and an alluvial aquifer contaminated with landfill leachate was investigated to evaluate factors that can effect natural attenuation of landfill leachate contaminants in areas of groundwater/surface-water interaction. The biogeochemistry at the wetland-alluvial aquifer interface differed greatly between dry and wet conditions. During dry conditions (low water table), vertically upward discharge was focused at the center of the slough from the fringe of a landfill-derived ammonium plume in the underlying aquifer, resulting in transport of relatively low concentrations of ammonium to the slough sediments with dilution and dispersion as the primary attenuation mechanism. In contrast, during wet conditions (high water table), leachate-contaminated groundwater discharged upward near the upgradient slough bank, where ammonium concentrations in the aquifer where high. Relatively high concentrations of ammonium and other leachate constituents also were transported laterally through the slough porewater to the downgradient bank in wet conditions. Concentrations of the leachate-associated constituents chloride, ammonium, non-volatile dissolved organic carbon, alkalinity, and ferrous iron more than doubled in the slough porewater on the upgradient bank during wet conditions. Chloride, non-volatile dissolved organic carbon (DOC), and bicarbonate acted conservatively during lateral transport in the aquifer and slough porewater, whereas ammonium and potassium were strongly attenuated. Nitrogen isotope variations in ammonium and the distribution of ammonium compared to other cations indicated that sorption was the primary attenuation mechanism for ammonium during lateral transport in the aquifer and the slough porewater. Ammonium attenuation was less efficient, however, in the slough porewater than in the aquifer and possibly occurred by a different sorption mechanism. A

  12. Pricing Liquidity Risk with Heterogeneous Investment Horizons

    NARCIS (Netherlands)

    Beber, Alessandro; Driessen, Joost; Neuberger, A.; Tuijp, P

    We develop an asset pricing model with stochastic transaction costs and investors with heterogeneous horizons. Depending on their horizon, investors hold different sets of assets in equilibrium. This generates segmentation and spillover effects for expected returns, where the liquidity (risk)

  13. Entropy of black holes with multiple horizons

    Science.gov (United States)

    He, Yun; Ma, Meng-Sen; Zhao, Ren

    2018-05-01

    We examine the entropy of black holes in de Sitter space and black holes surrounded by quintessence. These black holes have multiple horizons, including at least the black hole event horizon and a horizon outside it (cosmological horizon for de Sitter black holes and "quintessence horizon" for the black holes surrounded by quintessence). Based on the consideration that the two horizons are not independent each other, we conjecture that the total entropy of these black holes should not be simply the sum of entropies of the two horizons, but should have an extra term coming from the correlations between the two horizons. Different from our previous works, in this paper we consider the cosmological constant as the variable and employ an effective method to derive the explicit form of the entropy. We also try to discuss the thermodynamic stabilities of these black holes according to the entropy and the effective temperature.

  14. Hawking radiation from quasilocal dynamical horizons

    Indian Academy of Sciences (India)

    2016-01-06

    Jan 6, 2016 ... Abstract. In completely local settings, we establish that a dynamically evolving spherically symmetric black hole horizon can be assigned a Hawking temperature and with the emission of flux, radius of the horizon shrinks.

  15. Cosmological and black hole apparent horizons

    CERN Document Server

    Faraoni, Valerio

    2015-01-01

    This book overviews the extensive literature on apparent cosmological and black hole horizons. In theoretical gravity, dynamical situations such as gravitational collapse, black hole evaporation, and black holes interacting with non-trivial environments, as well as the attempts to model gravitational waves occurring in highly dynamical astrophysical processes, require that the concept of event horizon be generalized. Inequivalent notions of horizon abound in the technical literature and are discussed in this manuscript. The book begins with a quick review of basic material in the first one and a half chapters, establishing a unified notation. Chapter 2 reminds the reader of the basic tools used in the analysis of horizons and reviews the various definitions of horizons appearing in the literature. Cosmological horizons are the playground in which one should take baby steps in understanding horizon physics. Chapter 3 analyzes cosmological horizons, their proposed thermodynamics, and several coordinate systems....

  16. Results from the New Horizons encounter with Pluto

    Science.gov (United States)

    Olkin, C. B.; Stern, S. A.; Spencer, J. R.; Weaver, H. A.; Young, L. A.; Ennico, K.

    2017-09-01

    In July 2015, the New Horizons spacecraft flew through the Pluto system providing high spatial resolution panchromatic and color visible light imaging, near-infrared composition mapping spectroscopy, UV airglow measurements, UV solar and radio uplink occultations for atmospheric sounding, and in situ plasma and dust measurements that have transformed our understanding of Pluto and its moons. Results from the science investigations focusing on geology, surface composition and atmospheric studies of Pluto and its largest satellite Charon will be presented. We also describe the New Horizons extended mission.

  17. Kinetics of Organic Matter Biodegradation in Leachate from Tobacco Waste

    Directory of Open Access Journals (Sweden)

    Briški, F.

    2012-09-01

    Full Text Available Treatment of wastes and leachate evolved in landfills is today an imperative due to rigorous environmental protection legislation. In this work, biodegradation of the organic fraction in tobaccowaste leachate was studied. Experiments were carried out in a batch reactor at initial concentra tion of activated sludge of 3.03 g dm–3 and different initial concentrations of organic matter in leachate, expressed as COD, which ranged from 0.5 to 3.0 g dm–3 . The working volume of the reactor (Fig. 1 was 7 dm3 within the cylindrical porous liner and it was filled with the suspension of leachate and activated sludge . The liner was designed such that it did not allow activated sludge to pass through. Continuous up-flow aeration was provided by a membrane pump. The temperature during the biodegradation process was 23 ± 2 °C. Dissolved oxygen, pH and temperature in reactor were monitored continuously by probes connected to a remote meter. Toxicity of leachate was performed by toxicity test using marine bacteria Vibrio fischeri before starting with the biodegradation in the batch reactor. The obtained results showed that effective concentration of leachate is EC 50 = 1.6 g dm–3 and toxicity impact index is TII50 = 9.99, meaning that untreated leachate must not be discharged into the environment before treatment. The results of the biodegradation process of leachate in batch reactor are presented in Table 1 and Fig. 2. The ratio γXv/γX was almost constant throughout the experiments and ranged from 0.69 do 0.73. This implies that the concentration of biomass remained unchanged during the experiments, and average yield was 5.26 %. The important kinetic and stoichiometric parameters required for performance of the biological removal process, namely the Y, Ks, Kd, and μmax were calculated from the batch experiments (Table 2. The experimental results of the influence of initial substrate concentrations on substrate degradation rate, and influence of

  18. How the change in horizon area drives black hole evaporation

    International Nuclear Information System (INIS)

    Massar, S.; Parentani, R.

    2000-01-01

    We rephrase the derivation of black hole radiation so as to take into account, at the level of transition amplitudes, the change of the geometry induced by the emission process. This enlarged description reveals that the dynamical variables which govern the emission are the horizon area and its conjugate time variable. Their conjugation is established through the boundary term at the horizon which must be added to the canonical action of general relativity in order to obtain a well defined action principle when the area varies. These coordinates have already been used by Teitelboim and collaborators to compute the partition function of a black hole. We use them to show that the probability to emit a particle is given by e -ΔA/4 , where ΔA is the decrease in horizon area induced by the emission. This expression improves Hawking result which is governed by a temperature (given by the surface gravity) in that the specific heat of the black hole is no longer neglected. The present derivation of quantum black hole radiation is based on the same principles which are used to derive the first law of classical black hole thermodynamics. Moreover, it also applies to quantum processes associated with cosmological or acceleration horizons. These two results indicate that not only black holes but all event horizons possess an entropy which governs processes according to quantum statistical thermodynamics

  19. Determination of selected persistent organic pollutants in wastewater from landfill leachates, using an amperometric biosensor

    Science.gov (United States)

    Nomngongo, Philiswa N.; Catherine Ngila, J.; Msagati, Titus A. M.; Gumbi, Bhekumuzi P.; Iwuoha, Emmanuel I.

    Landfill leachates that contain persistent organic pollutants (POPs) are a big threat to groundwater systems and are projected to have hazardous effects in the long term if proper management strategies of the landfills are not put in place by those responsible. Monitoring the levels of POPs in landfill leachates is very crucial. This work presents an amperometric biosensor for determination of selected POPs in landfill leachates. The biosensor is based on kinetic inhibition of horseradish peroxidase (HRP). The enzyme was immobilised by electrostatic attachment on a polyaniline-modified Pt electrode surface. Selected POPs inhibited HRP enzyme activity and the decrease in the enzyme activity was used to determine these environmental pollutants. Selected polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs) and polychlorinated biphenyls (PCBs) were the analytes of choice because they are commonly found in South Africa water systems. Limits of detection for the amperometric biosensor were established as 0.014, 0.018, 0.022, 0.016 and 0.019 μg l-1 for BDE-100, PBB-1, PCB-1, PCB-28 and PCB-101, respectively. The HRP biosensor system gave different linear ranges for; BDE-100 (0.424-25.8 μg l-1), PBB-1 (0.862-13.4 μg l-1), PCB-1 (0.930-18.1 μg l-1), PCB-28 (0.730-15.7 μg l-1) and PCB-101 (0.930-27.1 μg l-1). Inhibition studies on HRP biosensor response toward the reduction of H2O2 in the absence and presence of the selected POPs were carried out to investigate the inhibition kinetics and its mechanism. The results obtained indicated that the inhibition mechanism was competitive for PBDEs and non-competitive for biphenyls (PCBs and PBBs). The application of the biosensor was tested on wastewater samples obtained from landfill leachate for determination of selected POPs. The leachate samples were found to contain PCB-28 (0.28 ± 0.03 μg l-1) and PCB-101 (0.31 ± 0.02 μg l-1). The samples were also analysed by GC-MS as a cross-check method and the

  20. Metal release from contaminated leaf litter and leachate toxicity for the freshwater crustacean Gammarus fossarum.

    Science.gov (United States)

    Maunoury-Danger, Florence; Felten, Vincent; Bojic, Clément; Fraysse, Fabrice; Cosin Ponce, Mar; Dedourge-Geffard, Odile; Geffard, Alain; Guérold, François; Danger, Michael

    2017-06-18

    Industrialization has left large surfaces of contaminated soils, which may act as a source of pollution for contiguous ecosystems, either terrestrial or aquatic. When polluted sites are recolonized by plants, dispersion of leaf litter might represent a non-negligible source of contaminants, especially metals. To evaluate the risks associated to contaminated leaf litter dispersion in aquatic ecosystems, we first measured the dynamics of metal loss from leaf litter during a 48-h experimental leaching. We used aspen (Populus tremula L.), a common tree species on these polluted sites, and collected leaf litter on three polluted sites (settling pond of a former steel mill) and three control sites situated in the same geographic area. Then, toxicity tests were carried out on individuals of a key detritivore species widely used in ecotoxicology tests, Gammarus fossarum (Crustacea, Amphipoda), with uncontaminated and contaminated leaf litter leachates, using a battery of biomarkers selected for their sensitivity to metallic stress. Leaf litters collected on polluted sites exhibited not only significantly higher cadmium and zinc concentrations but also lower lignin contents. All leaf litters released high amounts of chemical elements during the leaching process, especially potassium and magnesium, and, in a lesser extent, phosphorus, calcium, and trace metals (copper, cadmium, and zinc but not lead). Toxicity tests revealed that the most important toxic effects measured on G. fossarum were due to leaf litter leachates by themselves, whatever the origin of litter (from polluted or control sites), confirming the toxicity of such substances, probably due to their high content in phenolic compounds. Small additional toxic effects of leachates from contaminated leaf litters were only evidenced on gammarid lipid peroxidation, indicating that contaminated leaf litter leachates might be slightly more toxic than uncontaminated ones, but in a very reduced manner. Further studies will

  1. Influence of liming and topsoil thickness on vegetative growth and leachate quality on acidic coal refuse

    International Nuclear Information System (INIS)

    Li, R.S.; Daniels, W.L.

    1998-01-01

    Coal waste materials inhibit direct vegetation establishment due to adverse physical and chemical properties, particularly low water retention and high potential acidity. The Moss No. 1 coal refuse pile is located in Dickenson County, Virginia, and was idled in the late 1980's with little topsoil resource available for final closure. The refuse was acidic (Total-S = 0.38%; pH = 3.6), black, high (70%) in coarse fragments, and had a low water holding capacity (4.5% in 6.0 over a two-year period, which resulted in greater vegetative cover and biomass than the control plots. All topsoil treatments resulted in greater vegetative cover and biomass than plots treated with lime only due to improved surface soil physical and chemical properties. A topsoil treatment of 60 cm gave the thickest vegetative cover and biomass yield. Such a treatment, however, would be cost-prohibitive at this location. Application of 27 Mg/ha of lime to the refuse surface along with 15 cm of topsoil produced acceptable two-year vegetative cover and biomass, and appeared to be the optimal treatment for this particular situation. Both liming and topsoil had no affect on leachate pH and the electrical conductivity in leachates collected below the plots. This suggests that surface revegetation will have little effect on the quality of water draining through the pile, so long term water treatment requirements may not be reduced by successfully revegetating the pile surface

  2. EVALUATION OF LANDFILL LEACHATE POLLUTION: FINDINGS FROM A MONITORING STUDY AT MUNICIPAL WASTE LANDFILL

    Directory of Open Access Journals (Sweden)

    Magdalena Daria Vaverková

    2015-02-01

    Full Text Available The monitoring that was carried out at the landfill specialized in leachate, groundwater and surface water. There were 6 sampling sites. The observed parameters were pH, BOD5, CODCr, conductivity. Leachate reached the high values in all observed parameters. Groundwater samples were collected at two monitoring wells and the sampling site (A, B, C. Surface water was collected from two sampling sites (D, E. The pH showed slightly acid values at all sampling points. The pH of surface water was slightly acid to neutral. Both BOD5 and CODCr values ​​remained stable over the reporting period. The average conductivity value at sampling points D, E remained constant. In line with the Czech National Standard ČSN 75 7221 “Classification of Surface Water Quality” sampling point D belongs to II Water Quality Class – slightly polluted water and sampling site E to Class I water quality – unpolluted water. The authors believe that the fluctuations occurring with regard to the values of certain samples were not caused by the operation of the landfill itself, but were a result of the intense agricultural activity nearby the landfill.

  3. New Horizons in Cationic Photopolymerization

    Directory of Open Access Journals (Sweden)

    Marco Sangermano

    2018-01-01

    Full Text Available In this review, we report some recent advances and new horizons in UV-induced cationic photopolymerization. In particular, after a brief introduction on the discovery and affirmation of the cationic photopolymerization process, new efforts in the synthesis of cationic photoinitiators are reported. Subsequently, an interesting and absolutely new application is reported, related to the combination of Radical-Induced Cationic Photopolymerization with Frontal Polymerization, achieving the cross-linking of epoxy composites.

  4. Horizon universality and anomalous conductivities

    Energy Technology Data Exchange (ETDEWEB)

    Gürsoy, Umut [Institute for Theoretical Physics and Spinoza Institute, Utrecht University,3508 TD Utrecht (Netherlands); Tarrío, Javier [Departament de Física Fonamental and Institut de Ciències del Cosmos,Universitat de Barcelona, Martí i Franquès 1, ES-08028, Barcelona (Spain)

    2015-10-08

    We show that the value of chiral conductivities associated with anomalous transport is universal in a general class of strongly coupled quantum field theories that admit a gravitational holographic dual in the large N limit. Our result only applies to theories in the presence of external gauge fields with no dynamical gluon fields. On the gravity side the result follows from near horizon universality of the fluctuation equations, similar to the holographic calculation of the shear viscosity.

  5. Application of Vadose Zone Monitoring Technology for Characterization of Leachate Generation in Landfills

    Science.gov (United States)

    aharoni, imri; dahan, ofer

    2016-04-01

    Ground water contamination due to landfill leachate percolation is considered the most severe environmental threat related to municipal solid waste landfills. Natural waste degradation processes in landfills normally produce contaminated leachates up to decades after the waste has been buried. Studies have shown that understanding the mechanisms which govern attenuation processes and the fate of pollutants in the waste and in the underlying unsaturated zone is crucial for evaluation of environmental risks and selection of a restoration strategy. This work focuses on a closed landfill in the coastal plain of Israel that was active until 2002 without any lining infrastructure. A vadose zone monitoring system (VMS) that was implemented at the site enables continuous measurements across the waste body (15 m thick) and underlying sandy vadose zone (16 m thick). Data collected by the VMS included continuous measurements of water content as well as chemical composition of the leachates across the entire waste and vadose zone cross section. Results indicated that winter rain percolated through the waste, generating wetting waves which were observed across the waste and unsaturated sediment from land surface until groundwater at 31 m bls. Quick percolation and high fluxes were observed in spite of the clay cover that was implemented at the site as part of the rehabilitation scheme. The results show that the flow pattern is controlled by a preferential mechanism within the waste body. Specific sections showed rapid fluxes in response to rain events, while other sections remained unaffected. In the underlying sandy vadose zone the flow pattern exhibited characteristics of matrix flow. Yet, some sections received higher fluxes due to the uneven discharge of leachates from the overlying waste body. Water samples collected from the waste layer indicate production of highly polluted leachates over 14 years after the landfill was closed. The chemical composition within the waste

  6. Identification and assessment of water pollution as a consequence of a leachate plume migration from a municipal landfill site (Tucumán, Argentina).

    Science.gov (United States)

    Fernández, Diego S; Puchulu, María E; Georgieff, Sergio M

    2014-06-01

    Landfills constitute potential sources of different pollutants that could generate human health and environmental problems. While some landfills currently work under the protection of a bottom liner with leachate collection, it was demonstrated that migration could take place even yet with these cautions. The purpose of this paper is to assess the pollution caused by a leachate plume from a municipal landfill that is affecting both groundwater and surface waters. The research was carried out at Pacará Pintado landfill in northwestern Argentina. Analysis of water samples indicates that leachate is affecting groundwater under the landfill area and an abandoned river channel hydraulically connected. In the center of the landfill area, the plume is anoxic and sulfate, nitrate, iron and manganese reduction zones were identified. Leachate plume presented high concentration of organic matter, Fe, Mn, NH(4)(+), Cl(-) and Cr reaching an extension of 900 m. The presence of a leachate plume in a landfill site with a single liner system implies that the use of this groundwater pollution control method alone is not enough especially if permeable sediments are present below.

  7. Mutagenicity and genotoxicity of coal fly ash water leachate.

    Science.gov (United States)

    Chakraborty, Rajarshi; Mukherjee, Anita

    2009-03-01

    Fly ash is a by-product of coal-fired electricity generation plants. The prevalent practice of disposal is as slurry of ash and water to storage or ash ponds located near power stations. This has lain to waste thousands of hectares of land all over the world. Since leaching is often the cause of off-site contamination and pathway of introduction into the human environment, a study on the genotoxic effects of fly ash leachate is essential. Leachate prepared from the fly ash sample was analyzed for metal content, and tested for mutagenicity and genotoxicity. Analyses of metals show predominance of the metals-sodium, silicon, potassium, calcium, magnesium, iron, manganese, zinc, and sulphate. The Ames Salmonella mutagenicity assay, a short-term bacterial reverse mutation assay, was conducted on two-tester strains of Salmonella typhimurium strains TA97a and TA102. For genotoxicity, the alkaline version of comet assay on fly ash leachate was carried in vitro on human blood cells and in vivo on Nicotiana plants. The leachate was directly mutagenic and induced significant (Ppercentage (%), tail length (mum), and olive tail moment (arbitrary units). Our results indicate that leachate from fly ash dumpsites has the genotoxic potential and may lead to adverse effects on vegetation and on the health of exposed human populations.

  8. Impact of cigarette butt leachate on tidepool snails.

    Science.gov (United States)

    Booth, David J; Gribben, Paul; Parkinson, Kerryn

    2015-06-15

    In urban areas, cigarette butts are the most common discarded refuse articles. In marine intertidal zones, they often fall into tidepools. We tested how common intertidal molluscs were affected by butt leachate in a laboratory experiment, where snails were exposed to various leachate concentrations. Mortality was very high, with all species showing 100% mortality at the full leachate concentration (5 butts per litre and 2h soak time) after 8days. However, Austrocochlea porcata showed higher mortality than the other 2 species at lower concentrations (10%, 25%) which may affect the relative abundance of the 3 snails under different concentrations of leachate pollution. Also, sublethal effects of leachate on snail activity were observed, with greater activity of Nerita atramentosa than the other 2 species at higher concentrations, suggesting it is more resilient than the other 2 species. While human health concerns predominate with respect to smoking, we show strong lethal and sublethal (via behavioural modifications) impacts of discarded butts on intertidal organisms, with even closely-related taxa responding differently. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Isotherms and kinetics of lead and cadmium uptake from the waste leachate by natural and modified clinoptilolite

    Directory of Open Access Journals (Sweden)

    Maryam Faraji

    2012-01-01

    Conclusions: The modified zeolite with surfactant can be used as an appropriate adsorbent for the separation of heavy metals from waste Leachate. Lead and cadmium were absorbed in a single layer on the surface of the modified zeolite with surfactant, comparing different isoterm models, indicated that the capacity of the modified zeolite for lead adsorption was more than cadmium adsorption, but cadmium was absorbed with higher energy.

  10. The Comet Assay for the Evaluation of Genotoxic Potential of Landfill Leachate

    Directory of Open Access Journals (Sweden)

    Kamila Widziewicz

    2012-01-01

    Full Text Available Genotoxic assessment of landfill leachate before and after biological treatment was conducted with two human cell lines (Me45 and NHDF and Daphnia magna somatic cells. The alkali version of comet assay was used to examine genotoxicity of leachate by DNA strand breaks analysis and its repair dynamics. The leachate samples were collected from Zabrze landfill, situated in the Upper Silesian Industrial District, Poland. Statistically significant differences (Kruskal-Wallice ANOVA rank model were observed between DNA strand breaks in cells incubated with leachate before and after treatment (P<0.001. Nonparametric Friedman ANOVA confirmed time-reliable and concentration-reliable cells response to leachate concentration. Examinations of chemical properties showed a marked decrease in leachate parameters after treatment which correlate to reduced genotoxicity towards tested cells. Obtained results demonstrate that biological cotreatment of leachate together with municipal wastewater is an efficient method for its genotoxic potential reduction; however, treated leachate still possessed genotoxic character.

  11. Geometric properties of static Einstein-Maxwell dilaton horizons with a Liouville potential

    International Nuclear Information System (INIS)

    Abdolrahimi, Shohreh; Shoom, Andrey A.

    2011-01-01

    We study nondegenerate and degenerate (extremal) Killing horizons of arbitrary geometry and topology within the Einstein-Maxwell-dilaton model with a Liouville potential (the EMdL model) in d-dimensional (d≥4) static space-times. Using Israel's description of a static space-time, we construct the EMdL equations and the space-time curvature invariants: the Ricci scalar, the square of the Ricci tensor, and the Kretschmann scalar. Assuming that space-time metric functions and the model fields are real analytic functions in the vicinity of a space-time horizon, we study the behavior of the space-time metric and the fields near the horizon and derive relations between the space-time curvature invariants calculated on the horizon and geometric invariants of the horizon surface. The derived relations generalize similar relations known for horizons of static four- and five-dimensional vacuum and four-dimensional electrovacuum space-times. Our analysis shows that all the extremal horizon surfaces are Einstein spaces. We present the necessary conditions for the existence of static extremal horizons within the EMdL model.

  12. Nitrate retention capacity of milldam-impacted legacy sediments and relict A horizon soils

    Science.gov (United States)

    Weitzman, Julie N.; Kaye, Jason P.

    2017-05-01

    While eutrophication is often attributed to contemporary nutrient pollution, there is growing evidence that past practices, like the accumulation of legacy sediment behind historic milldams, are also important. Given their prevalence, there is a critical need to understand how N flows through, and is retained in, legacy sediments to improve predictions and management of N transport from uplands to streams in the context of climatic variability and land-use change. Our goal was to determine how nitrate (NO3-) is cycled through the soil of a legacy-sediment-strewn stream before and after soil drying. We extracted 10.16 cm radius intact soil columns that extended 30 cm into each of the three significant soil horizons at Big Spring Run (BSR) in Lancaster, Pennsylvania: surface legacy sediment characterized by a newly developing mineral A horizon soil, mid-layer legacy sediment consisting of mineral B horizon soil and a dark, organic-rich, buried relict A horizon soil. Columns were first preincubated at field capacity and then isotopically labeled nitrate (15NO3-) was added and allowed to drain to estimate retention. The columns were then air-dried and subsequently rewet with N-free water and allowed to drain to quantify the drought-induced loss of 15NO3- from the different horizons. We found the highest initial 15N retention in the mid-layer legacy sediment (17 ± 4 %) and buried relict A soil (14 ± 3 %) horizons, with significantly lower retention in the surface legacy sediment (6 ± 1 %) horizon. As expected, rewetting dry soil resulted in 15N losses in all horizons, with the greatest losses in the buried relict A horizon soil, followed by the mid-layer legacy sediment and surface legacy sediment horizons. The 15N remaining in the soil following the post-drought leaching was highest in the mid-layer legacy sediment, intermediate in the surface legacy sediment, and lowest in the buried relict A horizon soil. Fluctuations in the water table at BSR which affect

  13. Detailed landfill leachate plume mapping using 2D and 3D Electrical Resistivity Tomography - with correlation to ionic strength measured in screens

    DEFF Research Database (Denmark)

    Maurya, P.K.; Rønde, Vinni; Fiandaca, G.

    2017-01-01

    Leaching of organic and inorganic contamination from landfills is a serious environmental problem as surface water and aquifers are affected. In order to assess these risks and investigate the migration of leachate from the landfill, 2D and large scale 3D electrical resistivity tomography were used...... at a heavily contaminated landfill in Grindsted, Denmark. The inverted 2D profiles describe both the variations along the groundwater flow as well as the plume extension across the flow directions. The 3D inversion model shows the variability in the low resistivity anomaly pattern corresponding to differences...... in the ionic strength of the landfill leachate. Chemical data from boreholes agree well with the observations indicating a leachate plume which gradually sinks and increases in size while migrating from the landfill in the groundwater flow direction. Overall results show that the resistivity method has been...

  14. Stochastic Dynamics of Clay Translocation and Formation of Argillic Horizons

    Science.gov (United States)

    Calabrese, S.; Richter, D. D., Jr.; Porporato, A. M.

    2017-12-01

    The formation of argillic horizons in vertical soil profiles is mainly attributed to lessivage, namely the transport of clay from an upper E horizon to a deeper illuviated horizon. Because of the long timescales involved in this phenomenon, quantitative modeling is useful to explore the role of clay lessivage on soil formation and sub-surface clay accumulation. The limitations of detailed models of colloidal transport to short timescales make it necessary to resort to simple models. Here, we present a parsimonious model of clay transport in which lessivage is interpreted stochastically. Clay particles approach the soil surface at a speed equal to the erosion rate and are intermittently transported to deeper soil layers when percolation events occur or removed by erosion. Along with the evolution of clay particles trajectories, the model predicts the vertical clay profile, the depth of the B horizon, and the mean time to erosion. Dimensional analysis reveals the two dimensionless parameters governing the dynamics, leading to a new classification of soil types based on erosion rates and intensity of lessivage.

  15. Impact of Leachate Discharge from Cipayung Landfill on Water Quality of Pesanggrahan River, Indonesia

    Science.gov (United States)

    Noerfitriyani, Eki; Hartono, Djoko M.; Moersidik, Setyo S.; Gusniani, Irma

    2018-03-01

    The landfill operation can cause environmental problems due to solid waste decomposition in the form of leachate. The evaluation of environmental impacts related with solid waste landfilling is needed to ensure that leachate discharge to water bodies does not exceed the standard limit to prevent contamination of the environment. This study aims to analyze the impact of leachate discharge from Cipayung Landfill on water quality of Pesanggrahan River. The data were analyzed based on leachate samples taken from influent and effluent treatment unit, and river water samples taken from upstream, stream at leachate discharge, and downstream. All samples were taken three times under rainy season condition from April to May 2017. The results show the average leachate quality temperature is 34,81 °C, TSS 72.33 mg/L, pH 7.83, BOD 3,959.63 mg/L, COD 6,860 mg/L, TN 373.33 mg/L, Hg 0.0016 mg/L. The BOD5/COD ratio 0.58 indicated that leachate characteristics was biodegradable and resemble intermediate landfill due to the mixing of young leachate and old leachate. The effluent of leachate treatment plant exceeds the leachate standard limit for BOD, COD, and TN parameters. Statistical results from independent T-test showed significant differences (p<0,05) between upstream and downstream influenced with leachate discharge for DO parameter.

  16. 40 CFR 761.357 - Reporting the results of the procedure used to simulate leachate generation.

    Science.gov (United States)

    2010-07-01

    ... used to simulate leachate generation. 761.357 Section 761.357 Protection of Environment ENVIRONMENTAL... of the procedure used to simulate leachate generation. Report the results of the procedure used to simulate leachate generation as micrograms PCBs per liter of extract from a 100 gram sample of dry bulk...

  17. Evaluation of phytotoxicity of municipal landfill leachate before and after biological treatment

    Directory of Open Access Journals (Sweden)

    CR Klauck

    Full Text Available In the present study, leachate toxicity of a municipal solid waste landfill located in the Sinos River Valley region (southern Brazil was evaluated using plant bioassays. Leachate toxicity was assessed by analysis of seed germination and root elongation of lettuce (Lactuca sativa L. and rocket plant (Eruca sativa Mill. and root elongation of onions (Allium cepa L.. Bioassays were performed by exposing the seeds of L. sativa and E. sativa and the roots of A. cepa to raw leachate, treated leachate (biological treatment and negative control (tap water. The levels of metals detected in both samples of leachate were low, and raw leachate showed high values for ammoniacal nitrogen and total Kjeldahl nitrogen. There is a reduction in the values of several physicochemical parameters, which demonstrates the efficiency of the treatment. Both L. sativa and A. cepashowed a phytotoxic response to landfill leachate, showing reduced root elongation. However, the responses of these two plant species were different. Root elongation was significantly lower in A. cepa exposed to treated leachate, when compared to negative control, but did not show any difference when compared to raw leachate. In L. sativa, seeds exposed to the raw leachate showed significant reduction in root elongation, when compared to treated leachate and negative control. Seed germination showed no difference across the treatments. The results of the study show that plant species respond differently and that municipal solid waste landfill leachate show phytotoxicity, even after biological treatment.

  18. On black hole horizon fluctuations

    International Nuclear Information System (INIS)

    Tuchin, K.L.

    1999-01-01

    A study of the high angular momentum particles 'atmosphere' near the Schwarzschild black hole horizon suggested that strong gravitational interactions occur at invariant distance of the order of 3 √M [2]. We present a generalization of this result to the Kerr-Newman black hole case. It is shown that the larger charge and angular momentum black hole bears, the larger invariant distance at which strong gravitational interactions occur becomes. This invariant distance is of order 3 √((r + 2 )/((r + - r - ))). This implies that the Planckian structure of the Hawking radiation of extreme black holes is completely broken

  19. Membrane viewpoint on black holes: Dynamical electromagnetic fields near the horizon

    International Nuclear Information System (INIS)

    Macdonald, D.A.; Suen, W.

    1985-01-01

    This paper is part of a series of papers with the aim of developing a complete self-consistent formalism for the treatment of electromagnetic and gravitational fields in the neighborhood of a black-hole horizon. In this membrane formalism, the horizon is treated as a closed two-dimensional membrane lying in a curved three-dimensional space, and endowed with familiar physical properties such as entropy and temperature, surface pressure and viscosity, and electrical conductivity, charge, and current. This paper develops the concept of the ''stretched horizon,'' which will be vital for both the electromagnetic and gravitational aspects of the formalism, and it presents several model problems illustrating the interaction of dynamical electromagnetic fields with stationary black-hole horizons: The field of a test charge in various states of motion outside the Schwarzschild horizon is analyzed in the near-horizon limit, where the spatial curvature may be ignored and the metric may be approximated by that of Rindler. This analysis elucidates the influence of the horizon on the shapes and motions of electric and magnetic field lines when external agents move the field lines in arbitrary manners. It also illustrates how the field lines interact with the horizon's charge and current to produce an exchange of energy and momentum between the external agent and the horizon. A numerical calculation of the dynamical relaxation of a magnetic field threading a Schwarzschild black hole is also presented, illustrating the ''cleaning'' of a complicated field structure by a black-hole horizon, and elucidating the constraints on the location of the stretched horizon

  20. Variable horizon in a peridynamic medium.

    Energy Technology Data Exchange (ETDEWEB)

    Silling, Stewart Andrew; Littlewood, David John; Seleson, Pablo

    2014-10-01

    A notion of material homogeneity is proposed for peridynamic bodies with vari- able horizon but constant bulk properties. A relation is derived that scales the force state according to the position-dependent horizon while keeping the bulk properties un- changed. Using this scaling relation, if the horizon depends on position, artifacts called ghost forces may arise in a body under homogeneous deformation. These artifacts de- pend on the second derivative of horizon and can be reduced by use of a modified equilibrium equation using a new quantity called the partial stress . Bodies with piece- wise constant horizon can be modeled without ghost forces by using a technique called a splice between the regions. As a limiting case of zero horizon, both partial stress and splice techniques can be used to achieve local-nonlocal coupling. Computational examples, including dynamic fracture in a one-dimensional model with local-nonlocal coupling, illustrate the methods.

  1. Smooth horizons and quantum ripples

    International Nuclear Information System (INIS)

    Golovnev, Alexey

    2015-01-01

    Black holes are unique objects which allow for meaningful theoretical studies of strong gravity and even quantum gravity effects. An infalling and a distant observer would have very different views on the structure of the world. However, a careful analysis has shown that it entails no genuine contradictions for physics, and the paradigm of observer complementarity has been coined. Recently this picture was put into doubt. In particular, it was argued that in old black holes a firewall must form in order to protect the basic principles of quantum mechanics. This AMPS paradox has already been discussed in a vast number of papers with different attitudes and conclusions. Here we want to argue that a possible source of confusion is the neglect of quantum gravity effects. Contrary to widespread perception, it does not necessarily mean that effective field theory is inapplicable in rather smooth neighbourhoods of large black hole horizons. The real offender might be an attempt to consistently use it over the huge distances from the near-horizon zone of old black holes to the early radiation. We give simple estimates to support this viewpoint and show how the Page time and (somewhat more speculative) scrambling time do appear. (orig.)

  2. Intermittent rainstorms cause pulses of nitrogen, phosphorus, and copper in leachate from compost in bioretention systems

    International Nuclear Information System (INIS)

    Mullane, Jessica M.; Flury, Markus; Iqbal, Hamid; Freeze, Patrick M.; Hinman, Curtis; Cogger, Craig G.; Shi, Zhenqing

    2015-01-01

    Bioretention systems rely on vegetation and mixtures of soil, sand, and compost to filter stormwater runoff. However, bioretention systems can also leach metals and nutrients, and compost may be a major contributor to this leaching. To safely implement bioretention systems, it is crucial to determine the composition of compost leachate. We characterized and quantified the leachate composition of compost following intermittent, simulated storm events. Columns of municipal compost were irrigated to simulate 6-month, 24-hour rain storms in the Seattle–Tacoma region. Outflow was analyzed for pH, electrical conductivity (EC), particulate concentration, surface tension, dissolved organic carbon (DOC), nitrogen, phosphorus, and copper. Results indicate a decrease of chemical concentrations over the course of individual storms and following repeated storms, but each new storm released another peak of constituents. The decrease in phosphorus, copper, and DOC concentrations with repeated storms was slower than for nitrate and EC. Nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy (FTIR) showed that the DOC consisted mainly of aliphatic and aromatic components typical of fulvic and humic acids. Less than 3% of the original copper content from the compost leached out even after nine storm events. Nonetheless, copper concentrations in the leachate exceeded regulatory discharge standards. Our results show that compost can serve as a sustained source of leaching of nutrients and metals. - Highlights: • Intermittent rainstorms release N, P, and Cu from compost in bioretention systems. • Leaching of Cu is sustained over several years of rainfall. • Leaching of Cu is correlated with DOC concentrations. • Compost in bioretention systems can be a source of pollution.

  3. Intermittent rainstorms cause pulses of nitrogen, phosphorus, and copper in leachate from compost in bioretention systems

    Energy Technology Data Exchange (ETDEWEB)

    Mullane, Jessica M. [Department of Crop and Soil Sciences, Washington State University, Puyallup, WA 98371, Pullman, WA 99164 (United States); Flury, Markus, E-mail: flury@wsu.edu [Department of Crop and Soil Sciences, Washington State University, Puyallup, WA 98371, Pullman, WA 99164 (United States); Iqbal, Hamid [Department of Crop and Soil Sciences, Washington State University, Puyallup, WA 98371, Pullman, WA 99164 (United States); Institute of Environmental Sciences and Engineering, School of Civil and Environmental Engineering, National University of Sciences and Technology, Sector H-12, Islamabad (Pakistan); Freeze, Patrick M. [Department of Crop and Soil Sciences, Washington State University, Puyallup, WA 98371, Pullman, WA 99164 (United States); Hinman, Curtis [Natural Resources Program Extension, Washington State University, Puyallup, WA 98371 (United States); Cogger, Craig G.; Shi, Zhenqing [Department of Crop and Soil Sciences, Washington State University, Puyallup, WA 98371, Pullman, WA 99164 (United States)

    2015-12-15

    Bioretention systems rely on vegetation and mixtures of soil, sand, and compost to filter stormwater runoff. However, bioretention systems can also leach metals and nutrients, and compost may be a major contributor to this leaching. To safely implement bioretention systems, it is crucial to determine the composition of compost leachate. We characterized and quantified the leachate composition of compost following intermittent, simulated storm events. Columns of municipal compost were irrigated to simulate 6-month, 24-hour rain storms in the Seattle–Tacoma region. Outflow was analyzed for pH, electrical conductivity (EC), particulate concentration, surface tension, dissolved organic carbon (DOC), nitrogen, phosphorus, and copper. Results indicate a decrease of chemical concentrations over the course of individual storms and following repeated storms, but each new storm released another peak of constituents. The decrease in phosphorus, copper, and DOC concentrations with repeated storms was slower than for nitrate and EC. Nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy (FTIR) showed that the DOC consisted mainly of aliphatic and aromatic components typical of fulvic and humic acids. Less than 3% of the original copper content from the compost leached out even after nine storm events. Nonetheless, copper concentrations in the leachate exceeded regulatory discharge standards. Our results show that compost can serve as a sustained source of leaching of nutrients and metals. - Highlights: • Intermittent rainstorms release N, P, and Cu from compost in bioretention systems. • Leaching of Cu is sustained over several years of rainfall. • Leaching of Cu is correlated with DOC concentrations. • Compost in bioretention systems can be a source of pollution.

  4. The Pluto system after the New Horizons flyby

    Science.gov (United States)

    Olkin, Catherine B.; Ennico, Kimberly; Spencer, John

    2017-10-01

    In July 2015, NASA's New Horizons mission performed a flyby of Pluto, revealing details about the geology, surface composition and atmospheres of this world and its moons that are unobtainable from Earth. With a resolution as small as 80 metres per pixel, New Horizons' images identified a large number of surface features, including a large basin filled with glacial ices that appear to be undergoing convection. Maps of surface composition show latitudinal banding, with non-volatile material dominating the equatorial region and volatile ices at mid- and polar latitudes. This pattern is driven by the seasonal cycle of solar insolation. New Horizons' atmospheric investigation found the temperature of Pluto's upper atmosphere to be much cooler than previously modelled. Images of forward-scattered sunlight revealed numerous haze layers extending up to 200 km from the surface. These discoveries have transformed our understanding of icy worlds in the outer Solar System, demonstrating that even at great distances from the Sun, worlds can have active geologic processes. This Review addresses our current understanding of the Pluto system and places it in context with previous investigations. 

  5. Cartan invariants and event horizon detection

    Science.gov (United States)

    Brooks, D.; Chavy-Waddy, P. C.; Coley, A. A.; Forget, A.; Gregoris, D.; MacCallum, M. A. H.; McNutt, D. D.

    2018-04-01

    We show that it is possible to locate the event horizon of a black hole (in arbitrary dimensions) by the zeros of certain Cartan invariants. This approach accounts for the recent results on the detection of stationary horizons using scalar polynomial curvature invariants, and improves upon them since the proposed method is computationally less expensive. As an application, we produce Cartan invariants that locate the event horizons for various exact four-dimensional and five-dimensional stationary, asymptotically flat (or (anti) de Sitter), black hole solutions and compare the Cartan invariants with the corresponding scalar curvature invariants that detect the event horizon.

  6. Landfill leachate effects on sorption of organic micropollutants onto aquifer materials

    DEFF Research Database (Denmark)

    Larsen, Thomas; Christensen, Thomas Højlund; Pfeffer, Fred M.

    1992-01-01

    The effect of dissolved organic carbon as present in landfill leachate, on the sorption of organic micropollutants in aquifer materials was studied by laboratory batch and column experiments involving 15 non-polar organic chemicals, 5 landfill leachates and 4 aquifer materials of low organic carbon...... content. The experiments showed that hydrophobic organic micropollutants do partition into dissolved organic carbon found in landfill leachate potentially increasing their mobility. However, landfill leachate interacted with aquifer materials apparently increases the sorbent affinity for the hydrophobic......, the effect of landfill leachate on retardation of organic micropollutants in aquifer material seems limited....

  7. Landfill leachate as a mirror of today's disposable society: Pharmaceuticals and other contaminants of emerging concern in final leachate from landfills in the conterminous United States

    Science.gov (United States)

    Masoner, Jason R.; Kolpin, Dana W.; Furlong, Edward T.; Cozzarelli, Isabelle M.; Gray, James L.

    2015-01-01

    Final leachates (leachate after storage or treatment processes) from 22 landfills in 12 states were analyzed for 190 pharmaceuticals and other contaminants of emerging concern (CECs), which were detected in every sample, with the number of CECs ranging from 1 to 58 (median = 22). In total, 101 different CECs were detected in leachate samples, including 43 prescription pharmaceuticals, 22 industrial chemicals, 15 household chemicals, 12 nonprescription pharmaceuticals, 5 steroid hormones, and 4 animal/plant sterols. The most frequently detected CECs were lidocaine (91%, local anesthetic), cotinine (86%, nicotine degradate), carisoprodol (82%, muscle relaxant), bisphenol A (77%, component of plastics and thermal paper), carbamazepine (77%, anticonvulsant), and N,N-diethyltoluamide (68%, insect repellent). Concentrations of CECs spanned 7 orders of magnitude, ranging from 2.0 ng/L (estrone) to 17 200 000 ng/L (bisphenol A). Concentrations of household and industrial chemicals were the greatest (∼1000-1 000 000 ng/L), followed by plant/animal sterols (∼1000-100 000 ng/L), nonprescription pharmaceuticals (∼100-10 000 ng/L), prescription pharmaceuticals (∼10-10 000 ng/L), and steroid hormones (∼10-100 ng/L). The CEC concentrations in leachate from active landfills were significantly greater than those in leachate from closed, unlined landfills (p = 0.05). The CEC concentrations were significantly greater (p < 0.01) in untreated leachate compared with treated leachate. The CEC concentrations were significantly greater in leachate disposed to wastewater treatment plants from modern lined landfills than in leachate released to groundwater from closed, unlined landfills (p = 0.04). The CEC concentrations were significantly greater (p = 0.06) in the fresh leachate (leachate before storage or treatment) reported in a previous study compared with the final leachate sampled for the present study.

  8. A long-term comparative assessment of human health risk to leachate-contaminated groundwater from heavy metal with different liner systems.

    Science.gov (United States)

    Mishra, Harshit; Karmakar, Subhankar; Kumar, Rakesh; Kadambala, Praneeth

    2018-01-01

    The handling and management of municipal solid waste (MSW) are major challenges for solid waste management in developing countries. Open dumping is still the most common waste disposal method in India. However, landfilling also causes various environmental, social, and human health impacts. The generation of heavily polluted leachate is a major concern to public health. Engineered barrier systems (EBSs) are commonly used to restrict potentially harmful wastes by preventing the leachate percolation to groundwater and overflow to surface water bodies. The EBSs are made of natural (e.g., soil, clay) and/or synthetic materials such as polymeric materials (e.g., geomembranes, geosynthetic clay liners) by arranging them in layers. Various studies have estimated the human health risk from leachate-contaminated groundwater. However, no studies have been reported to compare the human health risks, particularly due to the leachate contamination with different liner systems. The present study endeavors to quantify the human health risk to contamination from MSW landfill leachate using multiple simulations for various EBSs. To quantify the variation in health risks to groundwater consumption to the child and adult populations, the Turbhe landfill of Navi Mumbai in India has been selected. The leachate and groundwater samples were collected continuously throughout January-September in 2015 from the landfill site, and heavy metal concentrations were analyzed using an inductively coupled plasma system. The LandSim 2.5 Model, a landfill simulator, was used to simulate the landfill activities for various time slices, and non-carcinogenic human health risk was determined for selected heavy metals. Further, the uncertainties associated with multiple input parameters in the health risk model were quantified under a Monte Carlo simulation framework.

  9. Characteristics and biological treatment of leachates from a domestic landfill

    Science.gov (United States)

    Waste material from urban areas is a major environmental concern and landfill application is a frequent method for waste disposal. The leachate from landfills can, however, negatively affect the surrounding environment. A bioreactor cascade containing submerged biofilms was used to treat newly forme...

  10. Redox zones of a landfill leachate pollution plume (Vejen, Denmark)

    DEFF Research Database (Denmark)

    Lyngkilde, John; Christensen, Thomas Højlund

    1992-01-01

    , ferrogenic, nitrate-reducing and aerobic environments overa distance of 370 m. This redox zone sequence is consistent with thermodynamical principles and is closely matched by the leachate plume determined by the chloride plume distribution. The redox zone sequence is believed to be key in controlling...

  11. Treatment of landfill leachate: Removal of ammonia by struvite ...

    African Journals Online (AJOL)

    2014-06-30

    Jun 30, 2014 ... Treatment of landfill leachate: Removal of ammonia by struvite formation. CC Camargo1, JR Guimarães1 and AL Tonetti1*. 1School of Civil Engineering, Architecture and Urbanism, FEC/UNICAMP, Avenida Albert Einstein, 951, Cidade Universitária 'Zeferino Vaz',. PO Box 6021, 13083-852, Campinas, SP, ...

  12. Groundwater and Leachate Monitoring and Sampling at ERDF, CY 2007

    Energy Technology Data Exchange (ETDEWEB)

    R. L. Weiss; T. A. Lee

    2008-06-25

    The purpose of this annual monitoring report is to evaluate the conditions of and identify trends for groundwater beneath the Environmental Restoration Disposal Facility and to report leachate results in fulfillment of the requirements specified in the ERDF Record of Decision and the ERDF Amended Record of Decision.

  13. Relative toxicity of cigarette butts leachate and usefulness of ...

    African Journals Online (AJOL)

    Relative acute toxicity of cigarette butts leachate, antioxidant biomarkers; superoxide dismutase (SOD), catalase (CAT), gluthathione (GSH)activity and lipid peroxidation (LPO), an index of malondialdehyde (MDA) were evaluated in Nile Tilapia (Oreochromis niloticus) exposed to two selected commonly consumed brand of ...

  14. Removal of trace elements from landfill leachate by calcite precipitation

    Czech Academy of Sciences Publication Activity Database

    Ettler, V.; Zelená, O.; Mihaljevič, M.; Šebek, O.; Strnad, L.; Coufal, P.; Bezdička, Petr

    2006-01-01

    Roč. 88, 1-3 (2006), s. 28-31 ISSN 0375-6742 R&D Projects: GA AV ČR(CZ) KJB3111402 Institutional research plan: CEZ:AV0Z40320502 Keywords : landfill leachate * calcite * scavenging Subject RIV: CA - Inorganic Chemistry Impact factor: 0.922, year: 2006

  15. Brain dysfunctions in Wistar rats exposed to municipal landfill leachates

    Directory of Open Access Journals (Sweden)

    Chibuisi G. Alimba

    2015-12-01

    Full Text Available Brain damage induced by Olusosun and Aba-Eku municipal landfill leachates was investigated in Wistar rats. Male rats were orally exposed to 1–25% concentrations of the leachates for 30 days. Catalase (CAT and superoxide dismutase (SOD activities, and malondialdehyde (MDA concentrations in the brain and serum of rats were evaluated; body and brain weight gain and histopathology were examined. There was significant (p < 0.05 decrease in body weight gain and SOD activity but increase in absolute and relative brain weight gain, MDA concentration and CAT activity in both brain and serum of treated rats. The biochemical parameters, which were more altered in the brain than serum, corroborated the neurologic lesions; neurodegeneration of purkinje cells with loss of dendrites, perineural vacuolations of the neuronal cytoplasm (spongiosis and neuronal necrosis in the brain. The concentrations of Cr, Cu, Pb, As, Cd, Mn, Ni, sulphates, ammonia, chloride and phosphate in the leachate samples were above standard permissible limits. The interactions of the neurotoxic constituents of the leachates induced the observed brain damage in the rats via oxidative damage. This suggests health risk in wildlife and human populations.

  16. Redox zones of a landfill leachate pollution plume (Vejen, Denmark)

    DEFF Research Database (Denmark)

    Lyngkilde, John; Christensen, Thomas Højlund

    1992-01-01

    Downgradient from an old municipal landfill allowing leachate, rich in dissolved organic carbon, to enter a shallow sandy aerobic aquifer, a sequence of redoxe zones is identified from groundwater chemical analysis. Below the landfill, methanogenic conditions prevail, followed by sulfidogenic...... the fate of reactive pollutants leached from the landfill....

  17. Improvement of landfill leachate biodegradability with ultrasonic process.

    Directory of Open Access Journals (Sweden)

    Amir Hossein Mahvi

    Full Text Available Landfills leachates are known to contain recalcitrant and/or non-biodegradable organic substances and biological processes are not efficient in these cases. A promising alternative to complete oxidation of biorecalcitrant leachate is the use of ultrasonic process as pre-treatment to convert initially biorecalcitrant compounds to more readily biodegradable intermediates. The objectives of this study are to investigate the effect of ultrasonic process on biodegradability improvement. After the optimization by factorial design, the ultrasonic were applied in the treatment of raw leachates using a batch wise mode. For this, different scenarios were tested with regard to power intensities of 70 and 110 W, frequencies of 30, 45 and 60 KHz, reaction times of 30, 60, 90 and 120 minutes and pH of 3, 7 and 10. For determining the effects of catalysts on sonication efficiencies, 5 mg/l of TiO(2 and ZnO have been also used. Results showed that when applied as relatively brief pre-treatment systems, the sonocatalysis processes induce several modifications of the matrix, which results in significant enhancement of its biodegradability. For this reason, the integrated chemical-biological systems proposed here represent a suitable solution for the treatment of landfill leachate samples.

  18. Sequential anaerobic/aerobic biotreatment of bark leachate.

    Science.gov (United States)

    Frigon, J C; Cimpoia, R; Guiot, S R

    2003-01-01

    Bark leachate is generated from sawmill operations such as log storage sites and contains polymeric tannins, carbohydrates, organic acids, phenolic and resin compounds. The present study was aimed at assessing the performance of a sequential anaerobic and aerobic treatment, for both chemical oxygen demand (COD) and phenol removal, under various combinations of operational conditions, in the continuous mode. After anaerobic treatment in a five litres upflow anaerobic sludge bed (UASB) reactor, the leachate was directed into two parallel aerobic reactors, either an activated sludge unit or a fixed film submerged filter (packed with polyethylene Flexirings), both of a volume of one litre and oxygenated by air diffusion. For a leachate of 22 gCOD/l, an overall COD removal of 96-98% was achieved at an hydraulic residence time (HRT) of 4 days for the anaerobic reactor and one day for either aerobic systems. The phenol concentration generally increased after anaerobic treatment but was below the detection limit (50 ppb) after aerobic polishing. Radiorespirometric microcosms with 14C-labelled phenol confirmed that phenol was mineralized in the aerobic reactors. The performances of both aerobic systems were similar for COD and phenol removal. Thus, a sequential anaerobic/aerobic treatment was able to effectively address the contamination of a bark leachate discharge, including phenols.

  19. Treatment of landfill leachate using Solar UV facilitated ...

    African Journals Online (AJOL)

    The use of heterogeneous photocatalytic degradation for the treatment of landfill leachate was investigated in this study. The photocatalytic degradation studies were carried out using Zinc oxide (ZnO) as photocatalyst and the process was facilitated by ultra violet radiation (UV) from sunlight. Characterisation of the raw ...

  20. levels of some physiochemical parameters in leachates from open

    African Journals Online (AJOL)

    WHO. Dumpsite leachates contained very high concentration of TDS which ranges between 5180.60±46.51mg/L -. 3071.80±38.96mg/L, BOD ... falls rapidly and many metal ions which are relatively insoluble at neutral pH can become ..... Chemical and Biological Methods for Seawater Analysis. 3rd ed. Oxford Pergamon ...

  1. Plant Leachate Nutrient Recovery with Biological, Thermal, and Photocatalytic Pretreatments

    Science.gov (United States)

    Wong, Les

    2015-01-01

    Plants are ideal for long term space travel: provide essential resources - oxygen, water, food; Water-soaked plants expel soluble nutrients in a leachate solution - toxins and wastes are also expelled and inhibit growth; biological, thermal, photocatalytic coupled with an acid digestion treatment will hopefully maximize recovery and remove wastes

  2. Semi-continuous anaerobic treatment of fresh leachate from ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-06-17

    Jun 17, 2009 ... This is because large amount of VFAs has also contributed to the COD measured in the treated leachate. In Phase 2, as a result of adjustment of pH by sodium hydroxide, COD effluent was continuously dec- reased until end of experiment. Since day 27 until day 33 increments in both acids were observed, ...

  3. Lead and chromium removal from leachate using horsetail (Equisetum hyemale

    Directory of Open Access Journals (Sweden)

    E. Kurniati

    2014-01-01

    Full Text Available Phytoremediation has been widely used for wastewater treatment technology. Horsetail was investigated for its capacity to remediate lead and chromium in leachate. This plant seemed to be an effective choice for phytoremediation due to its survival in extreme to moderate conditions, the availability of annual or perennial varieties and a deep root system. Conducted in a greenhouse, this research used leachate from final disposal. The leachate was exposed to six treated plants with three multiplications using activated natural zeolite media for one month. The treatments were flow system i.e. batch and continue, and living plants weight that is 0, 153 and 306 g planted in 20 cm diameter and 30 cm deep pots. The leachate pH, temperature, lead, and chromium concentration were observed and also the surrounding temperature and humidity. Results showed that 82.2% of lead can be removed by 153 gram horsetail on batch system as well as 61.2% chromium removal by 153 gram horsetail on continue system. Horsetail seemed to have future to be applied in phytoremediation of artisanal and small scale mining waste.

  4. Practical salinity management for leachate irrigation to poplar trees.

    Science.gov (United States)

    Smesrud, Jason K; Duvendack, George D; Obereiner, James M; Jordahl, James L; Madison, Mark F

    2012-01-01

    Landfill leachate can be beneficially reused for irrigation of fiber crops with appropriate attention to nutrient and salinity management. The Riverbend Landfill in Western Oregon has been effectively practicing irrigation of landfill leachate to poplar trees since 1993. Over that time, the site has been adaptively managed to control salinity impacts to the tree crop while beneficially utilizing the applied water and nutrients during each growing season. Representative leachate irrigation water has ranged in concentration of total dissolved solids from 777 to 6,940 mg/L, chloride from 180 to 1,760 mg/L and boron from 3.2 to 7.3 mg/L. Annual leachate irrigation applications have also ranged between 102 and 812 mm/yr. Important conclusions from this site have included: 1) Appropriate tree clone selection and tree stand spacing, thinning, and harvest rotations are critical to maintaining a productive tree stand that is resilient and resistant to salt stress. The most effective combinations have included clones DN-34, OP-367, 184-411, 49-177, and 15-29 planted at spacing of 3.7-m x 1.8-m to 3.7-m x 3.7-m; 2) Leaf tissue boron levels are closely correlated to soil boron levels and can be managed with leaching. When leaf tissue boron levels exceed 200 to 250 mg/kg, signs of salt stress may emerge and should be monitored closely; 3) Salinity from leachate irrigation can be managed to sustain a healthy tree crop by controlling mass loading rates and providing appropriate irrigation blending if necessary. Providing freshwater irrigation following each leachate irrigation and targeting freshwater irrigation as 30 percent of total irrigation water applied has successfully controlled salt impacts to vegetation; and 4) Drip irrigation generally requires more careful attention to long-term soil salinity management than spray irrigation. Moving drip irrigation tubes periodically to prevent the formation of highly saline zones within the soil profile is important. In this paper, a

  5. Evaluating the fate of organic leachate contaminants by use of multiple chemical tools in a clay till setting

    Science.gov (United States)

    Milosevic, N.; Qiu, S.; Elsner, M.; Albrechtsen, H.-J.; Bjerg, P. L.

    2012-04-01

    Leachate from old landfills situated in the vicinity of surface water bodies may affect the groundwater and subsequently surface water quality. It is suspected that the transition zone between groundwater and surface water can attenuate landfill leachate compounds, but the attenuation processes for organic leachate has not been studied in detail so far. Landfills are complex pollution sources and in particular in heterogeneous geologic settings evaluation of attenuation processes is the major challenge. The aim of this study was to evaluate the fate of key organic contaminants by use of chemical assessment tools in the anaerobic subsurface in the close vicinity of a local stream at Risby Landfill. The landfill leachate was mostly methanogenic and sulphate reducing or iron reducing with high concentrations of inorganic species. Phenoxy acid pesticides, chlorinated solvents and petroleum hydrocarbons (mainly BTEX) were identified as key contaminants beneath the landfill, but only pesticides were found in the leachate plume, in the groundwater/surface water transition zone and in the local stream. Analysis of metabolites, enantiomers and compound-specific isotopes (CSIA) (13C/12C) were used to assess attenuation processes and anaerobic degradation potentials, whereas aerobic microbial degradation was investigated for pesticides in a parallel study. The phenoxy acid 4-CPP, a potential transformation product of the pesticide dichlorprop, migrated to the aerobic stream sediments in high concentrations, where the parallel microbial study showed high degradation potential. Interestingly, 4-CPP/dichlorprop ratios were far higher than expected if 4-CPP originated as impurity in dichlorprop production. This indicates that in situ transformation of dichlorprop to 4-CPP or other unidentified compounds took place. Enantiomer fractions, measured along the groundwater flowpath, were associated with stable anaerobic conditions when >0.5, whereas values pollution source, which

  6. Optical geometry across the horizon

    International Nuclear Information System (INIS)

    Jonsson, Rickard

    2006-01-01

    In a recent paper (Jonsson and Westman 2006 Class. Quantum Grav. 23 61), a generalization of optical geometry, assuming a non-shearing reference congruence, is discussed. Here we illustrate that this formalism can be applied to (a finite four-volume) of any spherically symmetric spacetime. In particular we apply the formalism, using a non-static reference congruence, to do optical geometry across the horizon of a static black hole. While the resulting geometry in principle is time dependent, we can choose the reference congruence in such a manner that an embedding of the geometry always looks the same. Relative to the embedded geometry the reference points are then moving. We discuss the motion of photons, inertial forces and gyroscope precession in this framework

  7. Biogeochemical evolution of a landfill leachate plume, Norman, Oklahoma

    Science.gov (United States)

    Cozzarelli, Isabelle M.; Böhlke, John Karl; Masoner, Jason R.; Breit, George N.; Lorah, Michelle M.; Tuttle, Michele L.W.; Jaeschke, Jeanne B.

    2011-01-01

    Leachate from municipal landfills can create groundwater contaminant plumes that may last for decades to centuries. The fate of reactive contaminants in leachate-affected aquifers depends on the sustainability of biogeochemical processes affecting contaminant transport. Temporal variations in the configuration of redox zones downgradient from the Norman Landfill were studied for more than a decade. The leachate plume contained elevated concentrations of nonvolatile dissolved organic carbon (NVDOC) (up to 300 mg/L), methane (16 mg/L), ammonium (650 mg/L as N), iron (23 mg/L), chloride (1030 mg/L), and bicarbonate (4270 mg/L). Chemical and isotopic investigations along a 2D plume transect revealed consumption of solid and aqueous electron acceptors in the aquifer, depleting the natural attenuation capacity. Despite the relative recalcitrance of NVDOC to biodegradation, the center of the plume was depleted in sulfate, which reduces the long-term oxidation capacity of the leachate-affected aquifer. Ammonium and methane were attenuated in the aquifer relative to chloride by different processes: ammonium transport was retarded mainly by physical interaction with aquifer solids, whereas the methane plume was truncated largely by oxidation. Studies near plume boundaries revealed temporal variability in constituent concentrations related in part to hydrologic changes at various time scales. The upper boundary of the plume was a particularly active location where redox reactions responded to recharge events and seasonal water-table fluctuations. Accurately describing the biogeochemical processes that affect the transport of contaminants in this landfill-leachate-affected aquifer required understanding the aquifer's geologic and hydrodynamic framework.

  8. Hawking radiation from quasilocal dynamical horizons

    Indian Academy of Sciences (India)

    asymptotic observers perceive a thermal state and assign a physical temperature to the black hole. ... We construct positive frequency field modes on both sides of the horizon by considering the Kodama vec- tor field but the outgoing modes exhibit logarithmic singularities on the horizon under some approximation. However ...

  9. Competition, Time Horizon and Corporate Social Performance

    NARCIS (Netherlands)

    Graafland, J.J.; Smid, H.

    2013-01-01

    Abstract: This paper develops and tests a conceptual framework on the relationships between competition, time horizon and corporate social performance (CSP). We hypothesize that more intense competition discourages CSP by lowering the time horizon of companies. We test the hypothesis on a sample of

  10. The NMC Horizon Report: 2015 Museum Edition

    Science.gov (United States)

    Johnson, L.; Adams Becker, S.; Estrada, V.; Freeman, A.

    2015-01-01

    The internationally recognized series of "Horizon Reports" is part of the New Media Consortium's Horizon Project, a comprehensive research venture established in 2002 that identifies and describes emerging technologies likely to have a large impact over the coming years on a variety of sectors around the globe. This "2015 Horizon…

  11. The Horizon Report: 2010 Museum Edition

    Science.gov (United States)

    Johnson, L.; Witchey, H.; Smith, R.; Levine, A.; Haywood, K.

    2010-01-01

    The internationally recognized series of "Horizon Reports" is part of the New Media Consortium's Horizon Project, a comprehensive research venture established in 2002 that identifies and describes emerging technologies likely to have a large impact over the coming five years on a variety of sectors around the globe. This volume, the "2010 Horizon…

  12. Weakly Isolated horizons: first order actions and gauge symmetries

    International Nuclear Information System (INIS)

    Corichi, Alejandro; Reyes, Juan D; Vukašinac, Tatjana

    2017-01-01

    The notion of Isolated Horizons has played an important role in gravitational physics, being useful from the characterization of the endpoint of black hole mergers to (quantum) black hole entropy. With an eye towards a canonical formulation we consider general relativity in terms of connection and vierbein variables and their corresponding first order actions. We focus on two main issues: (i) The role of the internal gauge freedom that exists, in the consistent formulations of the action principle, and (ii) the role that a 3  +  1 canonical decomposition has in the allowed internal gauge freedom. More concretely, we clarify in detail how the requirement of having well posed variational principles compatible with general weakly isolated horizons (WIHs) as internal boundaries does lead to a partial gauge fixing in the first order descriptions used previously in the literature. We consider the standard Hilbert–Palatini action together with the Holst extension (needed for a consistent 3  +  1 decomposition), with and without boundary terms at the horizon. We show in detail that, for the complete configuration space—with no gauge fixing—, while the Palatini action is differentiable without additional surface terms at the inner WIH boundary, the more general Holst action is not. The introduction of a surface term at the horizon—that renders the action for asymptotically flat configurations differentiable—does make the Holst action differentiable, but only if one restricts the configuration space and partially reduces the internal Lorentz gauge. For the second issue at hand, we show that upon performing a 3  +  1 decomposition and imposing the time gauge, there is a further gauge reduction of the Hamiltonian theory in terms of Ashtekar–Barbero variables to a U (1)-gauge theory on the horizon. We also extend our analysis to the more restricted boundary conditions of (strongly) isolated horizons as inner boundary. We show that even when

  13. Evaluation of a buried vertical well leachate recirculation system for municipal solid waste landfills.

    Science.gov (United States)

    Kadambala, Ravi; Powell, Jon; Singh, Karamjit; Townsend, Timothy G

    2016-12-01

    Vertical liquids addition systems have been used at municipal landfills as a leachate management method and to enhance biostabilization of waste. Drawbacks of these systems include a limitation on pressurized injection and the occurrence of seepage. A novel vertical well system that employed buried wells constructed below a lift of compacted waste was operated for 153 days at a landfill in Florida, USA. The system included 54 wells installed in six clusters of nine wells connected with a horizontally-oriented manifold system. A cumulative volume of 8430 m 3 of leachate was added intermittently into the well clusters over the duration of the project with no incidence of surface seeps. Achievable average flow rates ranged from 9.3 × 10 -4 m 3 s -1 to 14.2 × 10 -4 m 3 s -1 , which was similar to or greater than flow rates achieved in a previous study using traditional vertical wells at the same landfill site. The results demonstrated that pressurized liquids addition in vertical wells at municipal solid waste landfills can be achieved while avoiding typical operational and maintenance issues associated with seeps. © The Author(s) 2016.

  14. Determination of Prazosin and Simvastatin in Landfill Leachate using Liquid Chromatography-Time of Flight-Mass Spectrometry

    International Nuclear Information System (INIS)

    Zainab Haider Mussa; Zainab Haider Mussa; Fouad Fadhil Al-Qaim; Fouad Fadhil Al-Qaim; Md Pauzi Abdullah; Mohamed Rozali Othman

    2016-01-01

    Human pharmaceuticals have been shown to occur in considerably high amounts in sewage treatment plant (STP) effluents and surface waters. So far there is no data available on the occurrence of prazosin and simvastatin in leachate sample in Malaysia. Thus, this study is the first report to analysis of prazosin and simvastatin in leachate samples by using solid phase extraction-liquid chromatography-time of flight-mass spectrometry (SPE-LC-TOF-MS). The proposed method included isolation and reconstitute procedure. The linearity range was achieved at 1.5-3000 μg/ L and 0.8-125 μg/ L for prazosin and simvstatin, respectively with a determination coefficient (R 2 ) > 0.99. The limit of quantification (LOQ) for prazosin and simvastatin was calculated at 2.1 and 0.5 ng/ L in deionised water (DIW), meanwhile it was recorded at 3.5 and 2.4 ng/ L for prazosin and simvastatin in effluent sample, respectively. Two pharmaceutical compounds were detected in the leachate samples: prazosin and simvastatin at concentrations levels of 3850 and 415 ng/ L, respectively. (author)

  15. Organic matters removal from landfill leachate by immobilized Phanerochaete chrysosporium loaded with graphitic carbon nitride under visible light irradiation.

    Science.gov (United States)

    Hu, Liang; Liu, Yutang; Zeng, Guangming; Chen, Guiqiu; Wan, Jia; Zeng, Yunxiong; Wang, Longlu; Wu, Haipeng; Xu, Piao; Zhang, Chen; Cheng, Min; Hu, Tianjue

    2017-10-01

    This study investigated the technical applicability of a combination of Phanerochaete chrysosporium (P. chrysosporium) with photocatalyst graphitic carbon nitride (g-C 3 N 4 ) for organic matters removal from landfill leachate under visible light irradiation. Photocatalyst g-C 3 N 4 was well immobilized on the hyphae surface of P. chrysosporium by calcium alginate. The typical absorption edge in visible light region for g-C 3 N 4 was at about 460 nm, and the optical absorption bandgap of g-C 3 N 4 was estimated to be 2.70 eV, demonstrating the great photoresponsive ability of g-C 3 N 4 . An optimized g-C 3 N 4 content of 0.10 g in immobilized P. chrysosporium and an optimized immobilized P. chrysosporium dosage of 1.0 g were suitable for organic matters removal. The removal efficiency of total organic carbon (TOC) reached 74.99% in 72 h with the initial TOC concentration of 100 mg L -1 . In addition, the gas chromatography coupled with mass spectrometry (GC-MS) measurements showed that immobilized P. chrysosporium presented an outstanding removal performance for almost all organic compounds in landfill leachate, especially for the volatile fatty acids and long-chain hydrocarbons. The overall results indicate that the combination P. chrysosporium with photocatalyst g-C 3 N 4 for organic matters removal from landfill leachate may provide a more comprehensive potential for the landfill leachate treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Horizon quantum mechanics of rotating black holes

    Energy Technology Data Exchange (ETDEWEB)

    Casadio, Roberto [Universita di Bologna, Dipartimento di Fisica e Astronomia, Bologna (Italy); I.N.F.N., Sezione di Bologna, I.S. FLAG, Bologna (Italy); Giugno, Andrea [Ludwig-Maximilians-Universitaet, Arnold Sommerfeld Center, Munich (Germany); Giusti, Andrea [Universita di Bologna, Dipartimento di Fisica e Astronomia, Bologna (Italy); I.N.F.N., Sezione di Bologna, I.S. FLAG, Bologna (Italy); Ludwig-Maximilians-Universitaet, Arnold Sommerfeld Center, Munich (Germany); Micu, Octavian [Institute of Space Science, Bucharest, P.O. Box MG-23, Bucharest-Magurele (Romania)

    2017-05-15

    The horizon quantum mechanics is an approach that was previously introduced in order to analyze the gravitational radius of spherically symmetric systems and compute the probability that a given quantum state is a black hole. In this work, we first extend the formalism to general space-times with asymptotic (ADM) mass and angular momentum. We then apply the extended horizon quantum mechanics to a harmonic model of rotating corpuscular black holes. We find that simple configurations of this model naturally suppress the appearance of the inner horizon and seem to disfavor extremal (macroscopic) geometries. (orig.)

  17. Implementing VMware Horizon View 5.2

    CERN Document Server

    Ventresco, Jason

    2013-01-01

    A step-by-step tutorial covering all components of the View Horizon suite in detail, to ensure that you can utilize all features of the platform, and discover all of the possible ways that it can be used within your own environment.If you are a newcomer in system administration, and you wish to implement a small to midsized Horizon View environment, then this book is for you. It will also benefit individuals who wish to administrate and manage Horizon View more efficiently or are studying for the VCP5-DT.

  18. Dynamical symmetry enhancement near IIA horizons

    International Nuclear Information System (INIS)

    Gran, University; Gutowski, J.; Kayani, University; Papadopoulos, G.

    2015-01-01

    We show that smooth type IIA Killing horizons with compact spatial sections preserve an even number of supersymmetries, and that the symmetry algebra of horizons with non-trivial fluxes includes an sl(2,ℝ) subalgebra. This confirms the conjecture of http://dx.doi.org/10.1007/JHEP11(2013)104 for type IIA horizons. As an intermediate step in the proof, we also demonstrate new Lichnerowicz type theorems for spin bundle connections whose holonomy is contained in a general linear group.

  19. Monitoring Bacteroides spp. markers, nutrients, metals and Escherichia coli in soil and leachate after land application of three types of municipal biosolids.

    Science.gov (United States)

    McCall, Crystal A; Jordan, Katerina S; Habash, Marc B; Dunfield, Kari E

    2015-03-01

    A lysimeter-based field study was done to monitor the transfer of culturable Escherichia coli, general (ALLBAC), human (Hf183) and swine (PIG-BAC-1) specific 16S rRNA Bacteroides spp. markers, nutrients and metals through soils and leachate over time following land application of a CP1/Class A as well as two CP2/Class B municipal biosolids (MBs). Hf183 markers were detected up to six days following application in soils receiving dewatered and liquid MBs, but not in leachate, suggesting their use in source tracking is better suited for recent pollution events. The CP2/Class B biosolids and swine manure contributed the highest microbial load with E. coli loads (between 2.5 and 3.7 log CFU (100 mL)(-1)) being greater than North American concentration recommendations for safe recreational water. ALLBAC persisted in soils and leachate receiving all treatments and was detected prior to amendment application demonstrating its unsuitability for identifying the presence of fecal pollution. A significant increase in NO₃-N (for Lystek and dewatered MBs) and total-P (for dewatered and liquid MBs) in leachate was observed in plots receiving the CP1/Class A and CP2/Class B type MBs which exceeded North American guidelines, suggesting impact to surface water. Metal (As, Cd, Cr, Co, Cu, Pb, Mo, Ni, Se, Zn and Hg) transfer was negligible in soil and leachate samples receiving all treatments. This study is one of the first to examine the fate of E. coli and Bacteroides spp. markers in situ following the land application of MBs where surface runoff does not apply. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. New geometries for black hole horizons

    Energy Technology Data Exchange (ETDEWEB)

    Armas, Jay [Physique Théorique et Mathématique,Université Libre de Bruxelles and International Solvay Institutes, ULB-Campus Plaine CP231, B-1050 Brussels (Belgium); Blau, Matthias [Albert Einstein Center for Fundamental Physics, University of Bern,Sidlerstrasse 5, 3012 Bern (Switzerland)

    2015-07-10

    We construct several classes of worldvolume effective actions for black holes by integrating out spatial sections of the worldvolume geometry of asymptotically flat black branes. This provides a generalisation of the blackfold approach for higher-dimensional black holes and yields a map between different effective theories, which we exploit by obtaining new hydrodynamic and elastic transport coefficients via simple integrations. Using Euclidean minimal surfaces in order to decouple the fluid dynamics on different sections of the worldvolume, we obtain local effective theories for ultraspinning Myers-Perry branes and helicoidal black branes, described in terms of a stress-energy tensor, particle currents and non-trivial boost vectors. We then study in detail and present novel compact and non-compact geometries for black hole horizons in higher-dimensional asymptotically flat space-time. These include doubly-spinning black rings, black helicoids and helicoidal p-branes as well as helicoidal black rings and helicoidal black tori in D≥6.

  1. Managing sulphur permitting for the Horizon project

    Energy Technology Data Exchange (ETDEWEB)

    Duane, Calvin [Canadian Natural (Canada)

    2011-07-01

    This document deals with the management of sulphur permitting. Sulphur permitting involves many different stakeholders such as Alberta Environment, the Energy Resources Conservation Board, and the public as well as factors such as the marketing perspectives and an air quality and air management and regulation framework which must be respected. An application under the Environmental Protection and Enhancement Act (EPEA) requires information on: sulphur recovery facilities, sulphur reduction, fuel gas sulphur content, storage, containment, groundwater monitoring and SO2 emissions. The Horizon project application submitted to the Energy Resources Conservation Board (ERCB) from Canadian Natural Resources Ltd details recovery standards, product sulphur content and the equipment, technologies, and processes that will be used for extracting sulphur. Public opinion is most vocal on the subjects of H2S emissions, visual impact, and the contamination of groundwater, surface water and soil. Marketing perspectives consist of considerations to do with shipping cost, which is higher than storage cost, and with competition from other sources provincially, nationally and internationally. Finally, air quality monitoring includes monitoring of the total reduced sulphur and terrestrial and aquatic monitoring.

  2. Review of the literature on leachates from coal storage piles

    Energy Technology Data Exchange (ETDEWEB)

    Davis, E.C.; Boegly, W.J. Jr.

    1978-01-01

    Runoff from coal storage piles associated with coal conversion or combustion facilities may represent a potential source of environmental pollution. This report is an assessment of existing information on coal pile leachate. The assessment indicates that few detailed studies have been conducted to date, and these are limited and the results are highly variable. More detailed long-range studies using various types of coal are recommended. These studies should be carried out both in the laboratory and in field-scale experiments.

  3. Domestic wells have high probability of pumping septic tank leachate

    Directory of Open Access Journals (Sweden)

    J. E. Bremer

    2012-08-01

    Full Text Available Onsite wastewater treatment systems are common in rural and semi-rural areas around the world; in the US, about 25–30% of households are served by a septic (onsite wastewater treatment system, and many property owners also operate their own domestic well nearby. Site-specific conditions and local groundwater flow are often ignored when installing septic systems and wells. In areas with small lots (thus high spatial septic system densities, shallow domestic wells are prone to contamination by septic system leachate. Mass balance approaches have been used to determine a maximum septic system density that would prevent contamination of groundwater resources. In this study, a source area model based on detailed groundwater flow and transport modeling is applied for a stochastic analysis of domestic well contamination by septic leachate. Specifically, we determine the probability that a source area overlaps with a septic system drainfield as a function of aquifer properties, septic system density and drainfield size. We show that high spatial septic system density poses a high probability of pumping septic system leachate. The hydraulic conductivity of the aquifer has a strong influence on the intersection probability. We find that mass balance calculations applied on a regional scale underestimate the contamination risk of individual drinking water wells by septic systems. This is particularly relevant for contaminants released at high concentrations, for substances that experience limited attenuation, and those that are harmful even at low concentrations (e.g., pathogens.

  4. Biosorption of gold from computer microprocessor leachate solutions using chitin.

    Science.gov (United States)

    Côrtes, Letícia N; Tanabe, Eduardo H; Bertuol, Daniel A; Dotto, Guilherme L

    2015-11-01

    The biosorption of gold from discarded computer microprocessor (DCM) leachate solutions was studied using chitin as a biosorbent. The DCM components were leached with thiourea solutions, and two procedures were tested for recovery of gold from the leachates: (1) biosorption and (2) precipitation followed by biosorption. For each procedure, the biosorption was evaluated considering kinetic, equilibrium, and thermodynamic aspects. The general order model was able to represent the kinetic behavior, and the equilibrium was well represented by the BET model. The maximum biosorption capacities were around 35 mg g(-1) for both procedures. The biosorption of gold on chitin was a spontaneous, favorable, and exothermic process. It was found that precipitation followed by biosorption resulted in the best gold recovery, because other species were removed from the leachate solution in the precipitation step. This method enabled about 80% of the gold to be recovered, using 20 g L(-1) of chitin at 298 K for 4 h. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Geochemistry of leachates from selected coal mining and combustion wastes

    Energy Technology Data Exchange (ETDEWEB)

    Kopsick, D.A.; Angino, E.E.

    1981-06-01

    During the mining of coal, large amounts of inorganic material (gob) are removed with the coal. After cleaning of the coal, this waste is deposited adjacent to the mined area. One of these gob piles, located in Barton County, Missouri, is evaluated as to chemical composition of the waste, leaching characteristics of the waste and mineralogy of secondary minerals deposited at the pile. Two types of coal combustion wastes, fly ash and bottom ash, from five coal producing provinces of the United States are discussed in relation to Ca, Mg, Na, K, Mn, Fe, Cu, Zn and Pb concentrations in the whole sample and in the leachate generated from these ashes. An evaluation of geology, hydrogeology, soil chemistry and groundwater chemistry at an ash disposal site of a coal-fired power plant showed elevated concentrations of Ca, Mg and Na+K in the leachate of the coal ash relative to native groundwater. Only trace amounts of Mn, Fe, Cu, Zn are present in the ash leachate and no degradation of the local groundwater quality is predicted for this site.

  6. Compost leachate treatment using polyaluminium chloride and nanofiltration

    Directory of Open Access Journals (Sweden)

    Simonič Marjana

    2017-06-01

    Full Text Available Laboratory scale filtration tests utilizing leachate were conducted to investigate fouling and filtration performance of nanofiltration membranes. The work presented in this study is conducted on real samples rather than model water. Physico-chemical analyses showed that the leachate contained a lot of organic substances, exceeding 20000 mg/L O2 expressed as chemical oxygen demand. Proper pre-treatment method must be chosen in order to reduce fouling index. Coagulation pre-treatment using poly-aluminium chloride was chosen. Two thin film polysulfone membranes were used, purchased by Osmonic Desal. The focus of this research is to assess the influence of the particle size and zeta-potential of the colloidal fraction in leachate on nanofiltration performance. The isoelectric point of both membranes was 4.7 and 4.3, respectively. The fouled membranes were negatively charged over the pH range with isoelectric point shifting to the left (lower pH indicating the foulant material mainly not charged. It was confirmed by its zeta-potential, measured at -2 mV.

  7. Artificial sweeteners as potential tracers of municipal landfill leachate

    International Nuclear Information System (INIS)

    Roy, James W.; Van Stempvoort, Dale R.; Bickerton, Greg

    2014-01-01

    Artificial sweeteners are gaining acceptance as tracers of human wastewater in the environment. The 3 artificial sweeteners analyzed in this study were detected in leachate or leachate-impacted groundwater at levels comparable to those of untreated wastewater at 14 of 15 municipal landfill sites tested, including several closed for >50 years. Saccharin was the dominant sweetener in old (pre-1990) landfills, while newer landfills were dominated by saccharin and acesulfame (introduced 2 decades ago; dominant in wastewater). Cyclamate was also detected, but less frequently. A case study at one site illustrates the use of artificial sweeteners to identify a landfill-impacted groundwater plume discharging to a stream. The study results suggest that artificial sweeteners can be useful tracers for current and legacy landfill contamination, with relative abundances of the sweeteners potentially providing diagnostic ability to distinguish different landfills or landfill cells, including crude age-dating, and to distinguish landfill and wastewater sources. -- Highlights: • Artificial sweeteners detected at 14 of 15 municipal landfill sites. • Concentrations comparable to wastewater even at sites closed for >50 yr. • Saccharin elevated at all sites; potentially diagnostic of landfill impacts. • Potential for age-dating recent (past 2 decades) waste with acesulfame. -- Artificial sweeteners may be useful for tracing landfill leachate contamination and distinguishing it from wastewater impacts

  8. Identification of causes of oil sands coke leachate toxicity

    International Nuclear Information System (INIS)

    Puttaswamy, N.; Liber, K.

    2010-01-01

    The potential causes of oil sands coke leachate toxicity were investigated. Chronic 7-day toxicity tests were conducted to demonstrate that oil sands coke leachates (CL) are acutely toxic to Ceriodaphnia dubia (C. dubia). CLs were generated in a laboratory to perform toxicity identification evaluation (TIE) tests in order to investigate the causes of the CL toxicity. The coke was subjected to a 15-day batch leaching process at 5.5 and 9.5 pH values. The leachates were then filtered and used for chemical and toxicological characterization. The 7-day estimates for the C. dubia survival were 6.3 for a pH of 5.5 and 28.7 per cent for the 9.5 CLs. The addition of EDTA significantly improved survival and reproduction in a pH of 5.5 CL, but not in a pH of 9.5 CL. The toxicity of the pH 5.5 CL was removed with a cationic resin treatment. The toxicity of the 9.5 pH LC was removed using an anion resin treatment. Toxicity re-appeared when nickel (Ni) and vanadium (V) were added back to the resin-treated CLs. Results of the study suggested that Ni and V were acting as primary toxicants in the pH 5.5 CL, while V was the primary cause of toxicity in the pH 9.5 CL.

  9. Household hazardous waste in municipal landfills: contaminants in leachate

    International Nuclear Information System (INIS)

    Slack, R.J.; Gronow, J.R.; Voulvoulis, N.

    2005-01-01

    Household hazardous waste (HHW) includes waste from a number of household products such as paint, garden pesticides, pharmaceuticals, photographic chemicals, certain detergents, personal care products, fluorescent tubes, waste oil, heavy metal-containing batteries, wood treated with dangerous substances, waste electronic and electrical equipment and discarded CFC-containing equipment. Data on the amounts of HHW discarded are very limited and are hampered by insufficient definitions of what constitutes HHW. Consequently, the risks associated with the disposal of HHW to landfill have not been fully elucidated. This work has focused on the assessment of data concerning the presence of hazardous chemicals in leachates as evidence of the disposal of HHW in municipal landfills. Evidence is sought from a number of sources on the occurrence in landfill leachates of hazardous components (heavy metals and xenobiotic organic compounds [XOC]) from household products and the possible disposal-to-emissions pathways occurring within landfills. This review demonstrates that a broad range of xenobiotic compounds occurring in leachate can be linked to HHW but further work is required to assess whether such compounds pose a risk to the environment and human health as a result of leakage/seepage or through treatment and discharge

  10. Effects of pipeline construction on chernozemic and solonetzic A and B horizons in Central Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Landsburg, S. (NOVA Corp. of Alberta, Calgary, AB (Canada))

    1989-05-01

    The effects of pipeline construction on agricultural soil quality ratings were evaluated for the A and B horizons of Orthic Dark Brown Chernozem and Dark Brown Solonetz soils at three sites in Central Alberta 1 wk after construction. At each site, samples of the Ap horizon from the spoil side, trench, and work side portions of a pipeline right-of-way were compared to a sample of the Ap horizon from an adjacent area unaffected by pipeline construction. Spoil material below replaced topsoil on the trench was compared to a sample of an undisturbed B horizon. Regardless of soil type or land use, construction had no effect on the Ap horizon on the work side. This was due to optimum weather conditions during construction; low rainfall resulted in lack of soil ruting and minimal soil mixing. For both soil types under cultivation, construction increased soluble salt concentrations in the Ap horizons on the spoil side due to mixing of topsoil and spoil materials. There were few effects on the Ap horizon on the spoil side in pasture land, due to trench only topsoil stripping and easy spoil removal from a well-developed sod layer. Both the Ap and spoil from the trench in the Dark Brown Solonetz had increased salt concentrations, while there were few changes in the Dark Brown Chernozem. Mixing of topsoil and spoil material, and bringing salt-enriched material to the spoil surface are thought to be reponsible for the effects due to construction were reflected in the Ap horizon of the trench and spoil side by changes in pH, electrical conductivity, soluble salts and bulk density. Even with the increases in the soil properties monitored, the results indicated that regardless of soil type or land use, pipeline construction did not significantly affect the agricultural soil quality of the A and B horizons. 12 refs., 3 figs., 2 tabs.

  11. Evaluating biotoxicity variations of landfill leachate as penetrating through the soil column.

    Science.gov (United States)

    Zhu, Na; Ku, Tingting; Li, Guangke; Sang, Nan

    2013-08-01

    Recent studies of leachate-induced ecotoxicity have focused on crude samples, while little attention has been given to changes in biotoxicity resulting from the environmental behavior of landfill leachate. Therefore, we set up a soil column to simulate the underground penetration of leachate into the soil layer, define the rules of migration and transformation of leachate pollutants, and determine the variation in toxicity of landfill leachate during penetration. The results demonstrated that: (1) landfill leachate inhibited the growth and chlorophyll levels, elevated the levels of lipid peroxidation and protein oxidation, and stimulated the antioxidant enzyme activities of barley seedlings. The effects generally displayed a peak value at 12-24 cm, slowly declined at 36-48 cm, and then rapidly decreased with penetrating distance in the column. (2) Statistical correlation analysis of the properties of leachate and the observed biotoxic effects revealed that COD, conductivity and heavy metals (esp. Ni, Mn, Cd) were positively correlated with variations in biotoxicity. (3) The microbial activity of outflowing leachate sampled from the 48 cm port was significantly higher than the activity from succedent ports, and the types of contaminants increased in the leachate outflowing from the same port, implying that microbial behaviors near the 48 cm port could be used to partially evaluate variations in the composition and biotoxicity of landfill leachate. Taken together, the above results illustrate the polluting characteristics of landfill leachate when penetrating a soil column and provide guidance for pollution control and risk assessment of landfill leachate. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Treatment of landfill leachate using ASBR combined with zeolite adsorption technology

    OpenAIRE

    Lim, Chi Kim; Seow, Ta Wee; Neoh, Chin Hong; Md Nor, Muhamad Hanif; Ibrahim, Zaharah; Ware, Ismail; Mat Sarip, Siti Hajar

    2016-01-01

    Sanitary landfilling is the most common way to dispose solid urban waste; however, improper landfill management may pose serious environmental threats through discharge of high strength polluted wastewater also known as leachate. The treatment of landfill leachate to fully reduce the negative impact on the environment, is nowadays a challenge. In this study, an aerobic sequencing batch reactor (ASBR) was proposed for the treatment of locally obtained real landfill leachate with initial ammoni...

  13. Effects of evolving quality of landfill leachate on microbial fuel cell performance.

    Science.gov (United States)

    Li, Simeng; Chen, Gang

    2018-01-01

    Microbial fuel cell (MFC) is a novel technology for landfill leachate treatment with simultaneous electric power generation. In recent years, more and more modern landfills are operating as bioreactors to shorten the time required for landfill stabilization and improve the leachate quality. For landfills to operate as biofilters, leachate is recirculated back to the landfill, during which time the organics of the leachate can be decomposed. Continuous recirculation typically results in evolving leachate quality, which chronologically corresponds to evolution stages such as hydrolysis, acidogenesis, acetogenesis, methanogenesis, and maturation. In this research, variable power generation (160 to 230 mW m -2 ) by MFC was observed when leachate of various evolutionary stages was used as the feed. The power density followed a Monod-type kinetic model with the chemical oxygen demand (COD) equivalent of the volatile fatty acids (VFAs) ( p < 0.001). The coulombic efficiency decreased from 20% to 14% as the leachate evolved towards maturation. The maximum power density linearly decreased with the increase of internal resistance, resulting from the change of the conductivity of the solution. The decreased conductivity boosted the internal resistance and consequently limited the power generation. COD removal as high as 90% could be achieved with leachate extracted from appropriate evolutionary stages, with a maximum energy yield of 0.9 kWh m -3 of leachate. This study demonstrated the importance of the evolving leachate quality in different evolutionary stages for the performance of leachate-fed MFCs. The leachate extracted from acidogenesis and acetogenesis were optimal for both COD reduction and energy production in MFCs.

  14. Ecotoxicological evaluation of leachate from the Limeira sanitary landfill with a view to identifying acute toxicity

    OpenAIRE

    José Euclides Stipp Paterniani; Ronaldo Teixeira Pelegrini; Núbia Natália de Brito Pelegrini

    2007-01-01

    Final disposal of solid waste is still a cause for serious impacts on the environment. In sanitary landfills, waste undergoes physical, chemical, and biological decomposition, generating biogas and leachate. Leachate is a highly toxic liquid with a very high pollution potential. The purpose of this work is to evaluate toxicity of in natura leachate samples collected from Limeira Sanitary Landfill, in Limeira, SP. The ecotoxicological evaluation comprised acute toxicity assays using as test or...

  15. Deepwater Horizon Seafood Safety Oracle Database (2010)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In 2010, the Deepwater Horizon oil spill occurred in the Gulf of Mexico. In response to this spill, the National Marine Fisheries Service initiated a data collection...

  16. Deep Water Horizon (HB1006, EK60)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Monitor and measure the biological, chemical, and physical environment in the area of the oil spill from the deep water horizon oil rig in the Gulf of Mexico. A wide...

  17. Tunnelling Phenomenon near an Apparent Horizon in Two-Dimensional Dilaton Gravity*

    Science.gov (United States)

    Cao, Li-Ming; Jiang, Xiao-Zhu; Pen, Yu-Xuan

    2017-09-01

    Based on the definition of the apparent horizon in a general two-dimensional dilaton gravity theory, we analyze the tunnelling phenomenon near the apparent horizon. In this theory the definition of the horizon is very different from those in higher-dimensional gravity theories. By using the Hamilton–Jacobi method, the spectrum of the radiation is obtained and the temperature of the radiation is read out from this spectrum. The temperature is proportional to the surface gravity of the apparent horizon as usual. Besides, in stationary cases we calculate the spectrum by using Parikh and Wilczek’s null geodesic method and the result conforms to that obtained by using the Hamilton–Jacobi method. This is expected since the Hamilton–Jacobi method applies to generic spacetimes, including stationary ones.

  18. Event and Apparent Horizon Finders for 3+1 Numerical Relativity

    Directory of Open Access Journals (Sweden)

    Thornburg Jonathan

    2007-06-01

    Full Text Available Event and apparent horizons are key diagnostics for the presence and properties of black holes. In this article I review numerical algorithms and codes for finding event and apparent horizons in numerically-computed spacetimes, focusing on calculations done using the 3+1 ADM formalism. The event horizon of an asymptotically-flat spacetime is the boundary between those events from which a future-pointing null geodesic can reach future null infinity and those events from which no such geodesic exists. The event horizon is a (continuous null surface in spacetime. The event horizon is defined nonlocally in time: it is a global property of the entire spacetime and must be found in a separate post-processing phase after all (or at least the nonstationary part of spacetime has been numerically computed.There are three basic algorithms for finding event horizons, based on integrating null geodesics forwards in time, integrating null geodesics backwards in time, and integrating null surfaces backwards in time. The last of these is generally the most efficient and accurate.In contrast to an event horizon, an apparent horizon is defined locally in time in a spacelike slice and depends only on data in that slice, so it can be (and usually is found during the numerical computation of a spacetime. A marginally outer trapped surface (MOTS in a slice is a smooth closed 2-surface whose future-pointing outgoing null geodesics have zero expansion Theta. An apparent horizon is then defined as a MOTS not contained in any other MOTS. The MOTS condition is a nonlinear elliptic partial differential equation (PDE for the surface shape, containing the ADM 3-metric, its spatial derivatives, and the extrinsic curvature as coefficients. Most “apparent horizon” finders actually find MOTSs.There are a large number of apparent horizon finding algorithms, with differing trade-offs between speed, robustness, accuracy, and ease of programming. In axisymmetry, shooting

  19. New horizons exploring jupiter, pluto, and beyond

    CERN Document Server

    Hamilton, John

    2017-01-01

    Simple text and "out-of-this-world" photography introduce readers to NASA's New Horizons space probe, and its mission to explore Jupiter, Pluto, and the mysterious objects of the Kuiper Belt. Important details include planning and construction of New Horizons, its launch from Earth, flybys of Jupiter and Pluto, and its continuing mission beyond our solar system. Aligned to Common Core Standards and correlated to state standards. A&D Xtreme is an imprint of Abdo Publishing, a division of ABDO.

  20. VMware Horizon View 6 desktop virtualization cookbook

    CERN Document Server

    Ventresco, Jason

    2014-01-01

    If you want a more detailed explanation concerning the implementation of several different core features of VMware Horizon View, this is the book for you. Whether you are new to VMware Horizon View or an existing user, this book will provide you with the knowledge you need to successfully deploy several core features and get introduced to the latest features of version 6.0 as well.

  1. Hawking radiation from quasilocal dynamical horizons

    Indian Academy of Sciences (India)

    The space–time is said to con- tain a black hole if M is not contained in J−(I +). The black hole region is denoted by. B = M − J−(I +) and the event horizon is the boundary of B [2]. The definition of event horizon thus requires that we are able to construct the future null infinity I + and hence, the entire future of the space–time ...

  2. West Valley low-level radioactive waste site revisited: Microbiological analysis of leachates

    Energy Technology Data Exchange (ETDEWEB)

    Gillow, J.B.; Francis, A.J.

    1990-10-01

    The abundance and types of microorganisms in leachate samples from the West Valley low-level radioactive waste disposal site were enumerated. This study was undertaken in support of the study conducted by Ecology and Environment, Inc., to assess the extent of radioactive gas emissions from the site. Total aerobic and anaerobic bacteria were enumerated as colony forming units (CFU) by dilution agar plate technique, and denitrifiers, sulfate-reducers and methanogens by the most probable number technique (MPN). Of the three trenches 3, 9, and 11 sampled, trench 11 contained the most number of organisms in the leachate. Concentrations of carbon-14 and tritium were highest in trench 11 leachate. Populations of aerobes and anaerobes in trench 9 leachate were one order of magnitude less than in trench 11 leachate while the methanogens were three orders of magnitude greater than in trench 11 leachate. The methane content from trench 9 was high due to the presence of a large number of methanogens; the gas in this trench also contained the most radioactivity. Trench 3 leachate contained the least number of microorganisms. Comparison of microbial populations in leachates sampled from trenches 3 and 9 during October 1978 and 1989 showed differences in the total number of microbial types. Variations in populations of the different types of organisms in the leachate reflect the changing nutrient conditions in the trenches. 14 refs., 3 figs., 4 tabs.

  3. Bacterial Growth on Photochemically Transformed Leachates from Aquatic and Terrestrial Primary Producers

    DEFF Research Database (Denmark)

    Anesio, A.M.; Nielsen, Jon Theil; Granéli, W.

    2000-01-01

    We measured bacterial growth on phototransformed dissolved organic matter (DOM) leached from eight different primary producers. Leachates (10 mg C liter-1) were exposed to artificial UVA + UVB radiation, or kept in darkness, for 20 h. DOM solutions were subsequently inoculated with lake water...... on leachate and type of bacterial growth criterion. Bacterial carbon utilization (biomass production plus respiration) over the entire incubation period (120 h) was enhanced by UV radiation of leachate from the terrestrial leaves, relative to carbon utilization in non-irradiated leachates. Conversely, carbon...

  4. West Valley low-level radioactive waste site revisited: Microbiological analysis of leachates

    International Nuclear Information System (INIS)

    Gillow, J.B.; Francis, A.J.

    1990-10-01

    The abundance and types of microorganisms in leachate samples from the West Valley low-level radioactive waste disposal site were enumerated. This study was undertaken in support of the study conducted by Ecology and Environment, Inc., to assess the extent of radioactive gas emissions from the site. Total aerobic and anaerobic bacteria were enumerated as colony forming units (CFU) by dilution agar plate technique, and denitrifiers, sulfate-reducers and methanogens by the most probable number technique (MPN). Of the three trenches 3, 9, and 11 sampled, trench 11 contained the most number of organisms in the leachate. Concentrations of carbon-14 and tritium were highest in trench 11 leachate. Populations of aerobes and anaerobes in trench 9 leachate were one order of magnitude less than in trench 11 leachate while the methanogens were three orders of magnitude greater than in trench 11 leachate. The methane content from trench 9 was high due to the presence of a large number of methanogens; the gas in this trench also contained the most radioactivity. Trench 3 leachate contained the least number of microorganisms. Comparison of microbial populations in leachates sampled from trenches 3 and 9 during October 1978 and 1989 showed differences in the total number of microbial types. Variations in populations of the different types of organisms in the leachate reflect the changing nutrient conditions in the trenches. 14 refs., 3 figs., 4 tabs

  5. Effects of leachate concentration on the integrity of solidified clay liners.

    Science.gov (United States)

    Xue, Qiang; Zhang, Qian

    2014-03-01

    This study aimed to evaluate the impact of landfill leachate concentration on the degradation behaviour of solidified clay liners and to propose a viable mechanism for the observed degradation. The results indicated that the unconfined compressive strength of the solidified clay decreased significantly, while the hydraulic conductivity increased with the leachate concentration. The large pore proportion in the solidified clay increased and the sum of medium and micro pore proportions decreased, demonstrating that the effect on the solidified clay was evident after the degradation caused by exposure to landfill leachate. The unconfined compressive strength of the solidified clay decreased with increasing leachate concentration as the leachate changed the compact structure of the solidified clay, which are prone to deformation and fracture. The hydraulic conductivity and the large pore proportion of the solidified clay increased with the increase in leachate concentration. In contrast, the sum of medium and micro pore proportions showed an opposite trend in relation to leachate concentration, because the leachate gradually caused the medium and micro pores to form larger pores. Notably, higher leachate concentrations resulted in a much more distinctive variation in pore proportions. The hydraulic conductivity of the solidified clay was closely related to the size, distribution, and connection of pores. The proportion of the large pores showed a positive correlation with the increase of hydraulic conductivity, while the sum of the proportions of medium and micro pores showed a negative correlation.

  6. Micronuclei induced by municipal landfill leachate in mouse bone marrow cells in vivo

    International Nuclear Information System (INIS)

    Li Guangke; Sang Nan; Zhao Youcai

    2004-01-01

    The induction of micronuclei (MN) in polychromatic erythrocytes (PCE) of mouse bone marrow by municipal landfill leachate was studied in vivo. Results showed that mouse exposure via drinking water containing various concentrations of leachate caused a significant increase of MN frequencies in a concentration (Chemical oxygen demand measured with potassium dichromate oxidation, COD Cr )-dependent manner. MN induction in female and male mice was different at higher concentrations. This implies that leachate is a genotoxic agent in mammalian cells and that exposure to leachate in an aquatic environment may pose a potential genotoxic risk to human beings

  7. Migration behavior of landfill leachate contaminants through alternative composite liners.

    Science.gov (United States)

    Varank, Gamze; Demir, Ahmet; Top, Selin; Sekman, Elif; Akkaya, Ebru; Yetilmezsoy, Kaan; Bilgili, M Sinan

    2011-08-01

    Four identical pilot-scale landfill reactors with different alternative composite liners were simultaneously operated for a period of about 540 days to investigate and to simulate the migration behaviors of phenolic compounds (phenol, 2-CP, 2-MP, 3-MP, 4-MP, 2-NP, 4-NP, 2,4-DNP, 2,4-DCP, 2,6-DCP, 2,4,5-TCP, 2,4,6-TCP, 2,3,4,6-TeCP, PCP) and heavy metals (Pb, Cu, Zn, Cr, Cd, Ni) from landfill leachate to the groundwater. Alternative landfill liners of four reactors consist of R1: Compacted clay liner (10 cm+10 cm, k=10(-8)m/sn), R2: Geomembrane (2 mm HDPE)+compacted clay liner (10 cm+10 cm, k=10⁻⁸ m/sn), R3: Geomembrane (2 mm HDPE)+compacted clay liner (10 cm, k=10⁻⁸ m/sn)+bentonite liner (2 cm)+compacted clay liner (10 cm, k=10⁻⁸ m/sn), and R4: Geomembrane (2 mm HDPE)+compacted clay liner (10 cm, k=10⁻⁸ m/sn)+zeolite liner (2 cm)+compacted clay liner (10 cm, k=10⁻⁸ m/sn). Wastes representing Istanbul municipal solid wastes were disposed in the reactors. To represent bioreactor landfills, reactors were operated by leachate recirculation. To monitor and control anaerobic degradation in the reactors, variations of conventional parameters (pH, alkalinity, chloride, conductivity, COD, TOC, TKN, ammonia and alcaly metals) were also investigated in landfill leachate samples. The results of this study showed that about 35-50% of migration of organic contaminants (phenolic compounds) and 55-100% of migration of inorganic contaminants (heavy metals) to the model groundwater could be effectively reduced with the use of bentonite and zeolite materials in landfill liner systems. Although leachate contaminants can reach to the groundwater in trace concentrations, findings of this study concluded that the release of these compounds from landfill leachate to the groundwater may potentially be of an important environmental concern based on the experimental findings. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Lagrangian Predictive Skill Assessment for the Deepwater Horizon Spill

    Science.gov (United States)

    Lipphardt, B. L.; Huntley, H. S.; Sulman, M.; Kirwan, A. D.

    2011-12-01

    The explosion and sinking of the Deepwater Horizon drilling platform produced enormous human, ecological, and economic impacts. At the same time this disaster provided an unprecedented amount of Lagrangian information on ocean processes, including a large number of surface and near-surface drifters deployed in the northeastern Gulf of Mexico as well as remotely sensed images of the surface oil slick. In addition several global and regional ocean model predictions were used to forecast the spill movements. These models generally exhibited large variations in the mesoscale flow near the Deepwater Horizon site, even though they all assimilated similar sets of ocean observations. This provides a unique opportunity to thoroughly assess model Lagrangian predictive skill. Here, the predictive skill of one model, a regional implementation of the Hybrid Coordinate Ocean Model (HYCOM), is evaluated using data from more than 80 drifter trajectories in the northern Gulf of Mexico. These trajectories are compared with maps of Lagrangian coherent structures, computed from near-surface model velocities, to determine whether the observations are consistent with the larger scale transport structure predicted by the model. We also discuss new metrics to assess model Lagrangian predictive skill of the plume movement.

  9. Horizons of hermeneutics: Intercultural hermeneutics in a globalizing world

    NARCIS (Netherlands)

    J. de Mul (Jos)

    2011-01-01

    textabstractStarting from the often-used metaphor of the "horizon of experience" this article discusses three different types of intercultural hermeneutics, which respectively conceive hermeneutic interpretation as a widening of horizons, a fusion of horizons, and a dissemination of horizons. It is

  10. Landfill leachate as a mirror of today's disposable society: Pharmaceuticals and other contaminants of emerging concern in final leachate from landfills in the conterminous United States.

    Science.gov (United States)

    Masoner, Jason R; Kolpin, Dana W; Furlong, Edward T; Cozzarelli, Isabelle M; Gray, James L

    2016-04-01

    Final leachates (leachate after storage or treatment processes) from 22 landfills in 12 states were analyzed for 190 pharmaceuticals and other contaminants of emerging concern (CECs), which were detected in every sample, with the number of CECs ranging from 1 to 58 (median = 22). In total, 101 different CECs were detected in leachate samples, including 43 prescription pharmaceuticals, 22 industrial chemicals, 15 household chemicals, 12 nonprescription pharmaceuticals, 5 steroid hormones, and 4 animal/plant sterols. The most frequently detected CECs were lidocaine (91%, local anesthetic), cotinine (86%, nicotine degradate), carisoprodol (82%, muscle relaxant), bisphenol A (77%, component of plastics and thermal paper), carbamazepine (77%, anticonvulsant), and N,N-diethyltoluamide (68%, insect repellent). Concentrations of CECs spanned 7 orders of magnitude, ranging from 2.0 ng/L (estrone) to 17,200,000 ng/L (bisphenol A). Concentrations of household and industrial chemicals were the greatest (∼1000-1,000,000 ng/L), followed by plant/animal sterols (∼1000-100,000 ng/L), nonprescription pharmaceuticals (∼100-10,000 ng/L), prescription pharmaceuticals (∼10-10,000 ng/L), and steroid hormones (∼10-100 ng/L). The CEC concentrations in leachate from active landfills were significantly greater than those in leachate from closed, unlined landfills (p = 0.05). The CEC concentrations were significantly greater (p landfills than in leachate released to groundwater from closed, unlined landfills (p = 0.04). The CEC concentrations were significantly greater (p = 0.06) in the fresh leachate (leachate before storage or treatment) reported in a previous study compared with the final leachate sampled for the present study. Published 2015 SETAC. This article is a US Government work and as such, is in the public domain in the United States.

  11. Fate and distribution of nitrogen in soil and plants irrigated with landfill leachate.

    Science.gov (United States)

    Cheng, C Y; Chu, L M

    2011-06-01

    Landfill leachate contains a high concentration of ammoniacal substances which can be a potential supply of N for plants. A bioassay was conducted using seeds of Brassica chinensis and Lolium perenne to evaluate the phytotoxicity of the leachate sample. A soil column experiment was then carried out in a greenhouse to study the effect of leachate on plant growth. Two grasses (Paspalum notatum and Vetiver zizanioides) and two trees (Hibiscus tiliaceus and Litsea glutinosa) were irrigated with leachate at the EC50 levels for 12 weeks. Their growth performance and the distribution of N were examined and compared with columns applied with chemical fertilizer. With the exception of P. notatum, plants receiving leachate and fertilizer grew better than those receiving water alone. The growth of L. glutinosa and V. zizanioides with leachate irrigation did not differ significantly from plants treated with fertilizer. Leachate irrigation significantly increased the levels of NH(x)-N in soil. Although NO(x)-N was below 1 mg NL(-1) in the leachate sample, the soil NO(x)-N content increased by 9-fold after leachate irrigation, possibly as a result of nitrification. Leachate irrigation at EC50 provided an N input of 1920 kg N ha(-1) over the experimental period, during which up to 1050 kg N ha(-1) was retained in the soil and biomass, depending on the type of vegetation. The amount of nutrient added seems to exceed beyond the assimilative capability. Practitioners should be aware of the possible consequence of N saturation when deciding the application rate if leachate irrigation is aimed for water reuse. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Optical Characterization and Bioavailability of Dissolved Organic Matter of Leaf Leachates from Restored and Forested Delmarva Bay Catchments

    Science.gov (United States)

    Reed, E.; Armstrong, A.

    2016-12-01

    The optical properties and lability of fresh leaf and litter leachates obtained from Delmarva wetlands were analyzed to gain a further understanding of the carbon inputs and outputs of that wetland system. Carbon entering the wetland system may be digested by microbes and then given off as either carbon dioxide or methane, both of which enter the atmosphere as greenhouse gases. Delmarva Bays are often considered geographically isolated and only have surface water present in certain times of year. The vegetation around the wetlands are assumed to be a major input of the dissolved organic matter (DOM) in the wetland surface water. An understanding of the sources and lability of wetland water DOM can lead to further insight into the connections between vegetation, wetland management, and carbon cycling. Two paired wetland sites were sampled in this study, each included a forested catchment and a prior-converted agricultural wetland that had undergone hydrological ecosystem restoration. Leaf samples of Liquidambar styraciflua, Acer rubrum, Nyssa sylvatica, Polygonum, and Typha were taken directly from the living plant or from surrounding ground as litter. Spectral properties of the leachates were determined from fluorescence and absorbance, including PARAFAC components, fluorescence index (FI), humification index (HI), and the specific ultraviolet absorbance (SUVA). Leachates were also incubated with microbes taken from Tuckahoe Creek, a stream to which all sampled sites eventually drain, to determine the bioavailability of the carbon. There were measurable differences found between samples obtained from leaves and litter, as well as a difference between the herbaceous and tree samples. The results obtained from this study can help create more accurate models of how carbon cycles through these wetlands, both in forested and restored environments.

  13. Deepwater Horizon Accident Investigation Report

    International Nuclear Information System (INIS)

    2010-09-01

    On the evening of April 20, 2010, a well control event allowed hydrocarbons to escape from the Macondo well onto Transocean's Deepwater Horizon, resulting in explosions and fire on the rig. Eleven people lost their lives, and 17 others were injured. The fire, which was fed by hydrocarbons from the well, continued for 36 hours until the rig sank. Hydrocarbons continued to flow from the reservoir through the wellbore and the blowout preventer (BOP) for 87 days, causing a spill of national significance. BP Exploration and Production Inc. was the lease operator of Mississippi Canyon Block 252, which contains the Macondo well. BP formed an investigation team that was charged with gathering the facts surrounding the accident, analyzing available information to identify possible causes and making recommendations to enable prevention of similar accidents in the future. The BP investigation team began its work immediately in the aftermath of the accident, working independently from other BP spill response activities and organizations. The ability to gather information was limited by a scarcity of physical evidence and restricted access to potentially relevant witnesses. The team had access to partial real-time data from the rig, documents from various aspects of the Macondo well's development and construction, witness interviews and testimony from public hearings. The team used the information that was made available by other companies, including Transocean, Halliburton and Cameron. Over the course of the investigation, the team involved over 50 internal and external specialists from a variety of fields: safety, operations, subsea, drilling, well control, cementing, well flow dynamic modeling, BOP systems and process hazard analysis. This report presents an analysis of the events leading up to the accident, eight key findings related to the causal chain of events and recommendations to enable the prevention of a similar accident. The investigation team worked separately

  14. Hawking radiation of charged Einstein-aether black holes at both Killing and universal horizons

    Science.gov (United States)

    Ding, Chikun; Wang, Anzhong; Wang, Xinwen; Zhu, Tao

    2016-12-01

    We study analytically quantum tunneling of relativistic and non-relativistic particles at both Killing and universal horizons of Einstein-Maxwell-aether black holes, after high-order curvature corrections are taken into account, for which the dispersion relation of the particles becomes nonlinear. Our results at the Killing horizons confirm the previous ones, i.e., at high frequencies the corresponding radiation remains thermal and the nonlinearity of the dispersion does not alter the Hawking radiation significantly. In contrary, non-relativistic particles are created at universal horizons and are radiated out to infinity. The radiation also has a thermal spectrum, and the corresponding temperature takes the form, TUHz = 2κUH (z - 1) / (2 πz), where z (z ≥ 2) denotes the power of the leading term in the nonlinear dispersion relation, κUH is the surface gravity of the universal horizon, defined by peering behavior of ray trajectories at the universal horizon. We also study the Smarr formula by assuming that: (a) the entropy is proportional to the area of the universal horizon, and (b) the first law of black hole thermodynamics holds, whereby we derive the Smarr mass, which in general is different from the total mass obtained at infinity. This indicates that one or both of these assumptions must be modified.

  15. Transformation of metals speciation in a combined landfill leachate treatment

    International Nuclear Information System (INIS)

    Wu Yanyu; Zhou Shaoqi; Chen Dongyu; Zhao Rong; Li Huosheng; Lin Yiming

    2011-01-01

    Landfill leachate was treated by a combined sequential batch reactor (SBR), coagulation, Fenton oxidation and biological aerated filter (BAF) technology. The metals in treatment process were fractionated into three fractions: particulate and colloidal (size charge filtration), free ion/labile (cation exchange) and non-labile fractions. Fifty percent to 66% Cu, Ni, Zn, Mn, Pb and Cd were present as particulate/colloidal matter in raw leachate, whereas Cr was present 94.9% as non-labile complexes. The free ion/labile fractions of Ni, Zn, Mg, Mn, Pb and Cd increased significantly after treatment except Cr. Fifty-nine percent to 100% of Al was present mainly as particulate/colloidal matter > 0.45 μm and the remaining portions were predicted as non-labile complexes except in coagulation effluent. The speciation of Fe varied significantly in various individual processes. Visual MINTEQ simulation showed that 95-100% colloidal species for Cu, Cd and Pb were present as metal-humic complexes even with the lower dissolved organic carbon. Optimum agreements for the free ion/labile species were within acidic solution, whereas under-estimated in alkaline effluents. Overestimated particulate/colloidal fraction consisted with the hypothesis that a portion of colloids in fraction < 0.45 μm were considered as dissolved. - Research Highlights: → Metals in various landfill leachate treatments were size charge fractionated and the speciation transformations were compared. → Species predictions of metals were simulated by Visual MINTEQ model. → Optimum agreements for the free ion/labile species were within acidic solution. → Predictions of colloidal species agree with experimental data well in alkaline solution.

  16. Phytotoxicity data safeguard the performance of the recipient plants in leachate irrigation

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, C.Y. [Department of Biology, Chinese University of Hong Kong, Shatin, N.T., Hong Kong (China); Chu, L.M. [Department of Biology, Chinese University of Hong Kong, Shatin, N.T., Hong Kong (China)]. E-mail: leemanchu@cuhk.edu.hk

    2007-01-15

    Leachates from an operating and a closed landfill were examined for their phytotoxicity by seed germination/root elongation tests using seeds of Brassica chinensis and Lolium perenne. Their EC50s ranged from 3% to 46% v/v, which varied remarkably with the operating status of the landfills. Seedlings of twelve tree species were grown in pots, which were irrigated with landfill leachate at the EC50 levels, with tap water as control. No tree mortality or growth inhibition was observed after 90 days of leachate application. Chlorophyll fluorescence measurement also showed that plants receiving leachate did not suffer from a decline in photosynthetic efficiency. Litsea glutinosa and Hibiscus tiliaceus had remarkable growth, and other non-N-fixers were not inferior to the N-fixing Acacia auriculiformis. Leachate irrigation improved soil N content, though P deficiency is still a problem. The seed bioassay provided a conservative estimate of the phytotoxicity of landfill leachate. Plants irrigated can be protected from growth inhibition when the leachate irrigation plan is designed with reference to phytotoxicity data. - Irrigated plants could be benefited by leachate when the application rate was determined according to phytotoxicity data.

  17. Investigating the effects of heavy metals in the waste leachate on the ...

    African Journals Online (AJOL)

    The main and fundamental scientific reason of scientific community attention to the issue of leachate pollution and its treatment is the possible danger of contamination of water, soil and to some extent air. The reason is that the leachate of landfill in fact is acomplex waste withhigh pollution. Today, in our country, especially ...

  18. Optimization of treatment leachates from young, middle-aged and elderly landfills with bipolar membrane electrodialysis.

    Science.gov (United States)

    Ilhan, Fatih; Yazici Guvenc, Senem; Avsar, Yasar; Kurt, Ugur; Gonullu, Mustafa Talha

    2017-11-01

    In this study, a bipolar membrane electrodialysis (BMED) process, which is thought to be an effective treatment method for leachate, was evaluated for leachates of three different ages ('young', 'middle-aged' and 'elderly'). The leachates were pretreated to eliminate membrane fouling problems prior to the BMED process. Experimental studies were carried out to determine optimal operating conditions for the three differently aged leachates in the BMED process. According to the experiment results, there was a high removal efficiency of conductivity determined at 4 membrane - 25 V for young and elderly leachate and at 1 membrane - 25 V for middle-aged leachate. It was found that the operating times required to reach the optimal endpoints (at conductivity of about 2 mS/cm) of BMED process were 90, 180 and 300 min for the middle-aged, young and elderly leachates, respectively. Under the optimum operating conditions for the BMED process, removal efficiencies of conductivity and chemical oxygen demand were determined to be 89.5% and 60% for young, 82.5% and 30% for middle-aged and 91.8% and 26% for elderly leachate, respectively.

  19. Evaluation of leachate dissolved organic nitrogen discharge effect on wastewater effluent quality.

    Science.gov (United States)

    Bolyard, Stephanie C; Reinhart, Debra R

    2017-07-01

    Nitrogen is limited more and more frequently in wastewater treatment plant (WWTP) effluents because of the concern of causing eutrophication in discharge waters. Twelve leachates from eight landfills in Florida and California were characterized for total nitrogen (TN) and dissolved organic nitrogen (DON). The average concentration of TN and DON in leachate was approximately 1146mg/L and 40mg/L, respectively. Solid-phase extraction was used to fractionate the DON based on hydrophobic (recalcitrant fraction) and hydrophilic (bioavailable fraction) chemical properties. The average leachate concentrations of bioavailable (bDON) and recalcitrant (rDON) DON were 16.5mg/L and 18.4mg/L, respectively. The rDON fraction was positively correlated, but with a low R 2 , with total leachate apparent color dissolved UV 254 , chemical oxygen demand (COD), and humic acid (R 2 equals 0.38, 0.49, and 0.40, respectively). The hydrophobic fraction of DON (rDON) was highly colored. This fraction was also associated with over 60% of the total leachate COD. Multiple leachate and wastewater co-treatment simulations were carried out to assess the effects of leachate on total nitrogen wastewater effluent quality using removals for four WWTPs under different scenarios. The calculated pass through of DON suggests that leachate could contribute to significant amounts of nitrogen discharged to aquatic systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Hydrochemical Characterization of a Tropical, Coastal Aquifer Affected by Landfill Leachate and Seawater Intrusion

    NARCIS (Netherlands)

    Mangimbulude, Jubhar C.; Goeltom, Mangihot T.; van Breukelen, B.M.; van Straalen, NM; Roling, WFM

    2016-01-01

    The hydrochemistry of landfill leachate and groundwater is affected by not only waste degradation processes, but also by external factors such as the geography of the landfilling site. Knowledge on the fate of landfill leachate in tropical countries will be beneficial for monitoring and regulatory

  1. Physiological responses of Vetiver plant (Vetiver zizanioides to municipal waste leachate

    Directory of Open Access Journals (Sweden)

    Sasan Mohsenzadeh

    2016-06-01

    Full Text Available Vetiver plant is tolerant to acidity and temperature variations. Has rapid growth for biomass production and has high tolerance to organic and non-organic compounds in municipal waste leachate for example heavy metals. So this plant is good for landfill cultivation. In this study, physiological responses to municipal waste leachate were studied. Statistical design was a randomized complete block and each block treated with different concentrations of latex at levels of zero, 15, 30, 45 and 60 percent compared to the original latex waste. The leachate collected from the Shiraz landfill and brought into the greenhouse. The physiological characterization including leaf area, dry weight, chlorophyll, anthocyanin, proline, soluble sugars and total protein were measured. The result indicated that the dry weight, chlorophyll and anthocyanin decrease with increasing of latex concentration. The leaf area, leaf relative water, soluble sugars and total protein increased with increasing latex concentration. Proline concentration at 15 percent of leachate increased significantly compared to controls, whereas at higher concentrations decreased. According to the results, it is recommended that 45 percent of leachate in a landfill can be used to irrigate Vetiver. This is the maximum concentration of leachate that Vetiver plant can survive as green space. Primary filtration of leachate before using is recommended. If the aim is more growth or perfume application from root, less concentration of leachate is better.

  2. Toxicity of leachate from weathering plastics: An exploratory screening study with Nitocra spinipes.

    Science.gov (United States)

    Bejgarn, Sofia; MacLeod, Matthew; Bogdal, Christian; Breitholtz, Magnus

    2015-08-01

    Between 60% and 80% of all marine litter is plastic. Leachate from plastics has previously been shown to cause acute toxicity in the freshwater species Daphnia magna. Here, we present an initial screening of the marine environmental hazard properties of leachates from weathering plastics to the marine harpacticoid copepod [Crustacea] Nitocra spinipes. Twenty-one plastic products made of different polymeric materials were leached and irradiated with artificial sunlight. Eight of the twenty-one plastics (38%) produced leachates that caused acute toxicity. Differences in toxicity were seen for different plastic products, and depending on the duration of irradiation. There was no consistent trend in how toxicity of leachate from plastics changed as a function of irradiation time. Leachate from four plastics became significantly more toxic after irradiation, two became significantly less toxic and two did not change significantly. Analysis of leachates from polyvinyl chloride (PVC) by liquid chromatography coupled to a full-scan high-resolution mass spectrometer showed that the leachates were a mixture of substances, but did not show evidence of degradation of the polymer backbone. This screening study demonstrates that leachates from different plastics differ in toxicity to N. spinipes and that the toxicity varies under simulated weathering. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Treatment of Navy Landfill Leachate Contaminated with Low Levels of Priority Pollutants

    Science.gov (United States)

    1991-10-01

    leachate recirculation, contaminated groundwater, 160 carbon adsorption, ion exchange I6. PACE CODE 17. SECUIWTY CLASIFICATION 16. SECURTY CLASSIFICATION...tanks can be constructed of steel , concrete, or lined earthen materials. Provisions should be rade for mixing the leachate to prevent the deposition

  4. Impact of SRT on the performance of MBRs for the treatment of high strength landfill leachate

    KAUST Repository

    El-Fadel, M.

    2017-12-14

    This study examines the performance and fouling potential of flat sheet (FS) and hollow fiber (HF) membrane bioreactors (MBRs) during the treatment of high strength landfill leachate under varying solid retention times (SRT = 5–20 days). Mixed-liquor bacterial communities were examined over time using 16S rRNA gene sequence analysis in an attempt to define linkages between the system performance and the microbial community composition. Similarly, biofilm samples were collected at the end of each SRT to characterize the microbial communities that evolved on the surface of the FS and HF membranes. In general, both systems exhibited comparable removal efficiencies that dropped significantly as SRT was decreased down to 5 days. Noticeably, ammonia and nitrite oxidizing bacteria were not detected at the tested SRTs. This suggests that the nitrifiers were not enriched, possibly due to the high organic and ammonium content of the leachate that led to low TN and NH3 removal efficiency. The steady-state fouling rate of both membranes increased linearly with the decrease in SRT at an estimated factor of 1.1 and 1.2 for the FS- and HF-MBR, respectively, when the SRT was reduced from 15 to 10 days and from 10 to 5 days. Similar dominant genera were detected in both MBRs, including Pseudomonas, Aequorivita, Ulvibacter, Taibaiella, and Thermus. Aequorivita, Taibaiella; Thermus were the dominant genera in the biofilms. Hierarchical clustering and non-metric multidimensional scaling revealed that while the mixed liquor communities in the FS-MBR and HF-MBRs were dynamic, they clustered separately. Similarly, biofilm communities on the FS and HF membranes differed in the dynamic bacterial community structure, especially for the FS-MBR; however this was less dynamic than the mixed liquor community.

  5. Groundwater and Leachate Monitoring and Sampling at ERDF, CY 2010

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, R. L.; Lawrence, B. L.

    2011-06-09

    The purpose of this annual monitoring report is to evaluate the conditions of and identify trends for groundwater beneath the ERDF and report leachate results in fulfillment of the requirements specified in the ERDF ROD2 and the ERDF Amended ROD (EPA 1999). The overall objective of the groundwater monitoring program is to determine whether ERDF has impacted the groundwater. This objective is complicated by the fact that the ERDF is situated downgradient of the numerous groundwater contamination plumes originating from the 200 West Area.

  6. Managing the leachate at the regional landfill in Kikinda

    Directory of Open Access Journals (Sweden)

    Marković Sanja

    2016-01-01

    Full Text Available In developed, industrial countries, there is 1.2kg waste per capita, waste being collected and disposed of in regulated, sanitary landfills, which have systems for the protection of groundwater and air from pollutants, in Serbia, the largest number of landfills does not meet even the basic safety criteria for environmental protection. Several municipalities in Serbia began with the organization of the regional waste management system and within that frame, the construction of regional landfills which meet European standards in terms of environmental protection. The paper presents a method of management and use of leachate at the regional waste landfill 'ASA', Kikinda.

  7. Treatment of landfill leachate using a solar destillar

    Directory of Open Access Journals (Sweden)

    José Fernando Thomé Jucá

    2012-04-01

    Full Text Available The subject of this research was to build, develop, evaluate and optimize a system of natural evaporation of leachate, to reduce the organic loads. Physical and chemical microbiological parameters were monitored during the experiment to evaluate the system performance. The solar radiation and rainfall influence on the evaporator was investigated. The results showed 100% reduction of the turbidity, color and total solids. The values of BOD, COD, thermotolerants and total coliforms in the treated effluent had concentrations that meet the Brazilian Federal Environmental Council (CONAMA standards. Based on the results, it was concluded that the natural solar system was adequate for small landfills.

  8. Evaluation of the biodegradability and toxicity of landfill leachates after pretreatment using advanced oxidative processes.

    Science.gov (United States)

    da Costa, Fabio Moraes; Daflon, Sarah Dario Alves; Bila, Daniele Maia; da Fonseca, Fabiana Valeria; Campos, Juacyara Carbonelli

    2018-02-19

    Leachate from urban solid waste landfills is a complex mixture of organic and inorganic substances that cause damage to the environment, due to the high concentration of recalcitrant organic matter and toxicity. The objective of this study was to apply advanced oxidation processes (AOP), namely the dark Fenton and solar photo-Fenton processes, to young and old landfill leachates prior to biological treatment. The leachates were obtained from the Seropedica and Gramacho landfill sites, respectively, located in Rio de Janeiro State, Brazil. For the two Fenton processes, different conditions of pH (1.5, 3.0 and 5.0) and Fe 2+ : H 2 O 2 ratio (1:2, 1:5 and 1:10) were evaluated. Biodegradability was evaluated using the Zahn-Wellens methodology and Aliivibrio fischeri acute toxicity tests were conducted in order to predict the toxicity in the activated sludge. The best conditions for both Fenton processes were pH of 3.0 and Fe 2+ : H 2 O 2 and COD RAW :H 2 O 2 mass ratios of 1:5 and 1:1, respectively. The solar photo-Fenton process was more effective at improving the quality for both leachates, reaching COD, TOC and abs 254 nm reductions of 82%, 85% and 96.3%, respectively, for the Seropedica landfill leachate. In the case of the Gramacho landfill leachate, the corresponding reductions were 78.2, 80.7% and 91.1%, respectively. The biodegradability results for the untreated leachates from the Seropedica and Gramacho sites were 65% and 30% respectively. The biodegradability of both leachates was improved by the Fenton processes, especially the solar photo-Fenton process, which increased the leachate biodegradability to 89% (Seropedica) and 69% (Gramacho). For both leachates, a greater reduction in the acute toxicity was achieved with the solar photo-Fenton compared to the dark-Fenton process. The Seropedica landfill leachate showed high toxicity (EC50 = 33%, 15 min), after the dark Fenton and solar photo Fenton processes, with EC50 values of 81 and 91

  9. Quantum-corrected geometry of horizon vicinity

    Energy Technology Data Exchange (ETDEWEB)

    Park, I.Y. [Department of Applied Mathematics, Philander Smith College, Little Rock, AR (United States)

    2017-12-15

    We study the deformation of the horizon-vicinity geometry caused by quantum gravitational effects. Departure from the semi-classical picture is noted, and the fact that the matter part of the action comes at a higher order in Newton's constant than does the Einstein-Hilbert term is crucial for the departure. The analysis leads to a Firewall-type energy measured by an infalling observer for which quantum generation of the cosmological constant is critical. The analysis seems to suggest that the Firewall should be a part of such deformation and that the information be stored both in the horizon-vicinity and asymptotic boundary region. We also examine the behavior near the cosmological horizon. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Horizon thermodynamics in fourth-order gravity

    Directory of Open Access Journals (Sweden)

    Meng-Sen Ma

    2017-03-01

    Full Text Available In the framework of horizon thermodynamics, the field equations of Einstein gravity and some other second-order gravities can be rewritten as the thermodynamic identity: dE=TdS−PdV. However, in order to construct the horizon thermodynamics in higher-order gravity, we have to simplify the field equations firstly. In this paper, we study the fourth-order gravity and convert it to second-order gravity via a so-called “Legendre transformation” at the cost of introducing two other fields besides the metric field. With this simplified theory, we implement the conventional procedure in the construction of the horizon thermodynamics in 3 and 4 dimensional spacetime. We find that the field equations in the fourth-order gravity can also be written as the thermodynamic identity. Moreover, we can use this approach to derive the same black hole mass as that by other methods.

  11. On Long Memory Origins and Forecast Horizons

    DEFF Research Database (Denmark)

    Vera-Valdés, J. Eduardo

    Most long memory forecasting studies assume that the memory is generated by the fractional difference operator. We argue that the most cited theoretical arguments for the presence of long memory do not imply the fractional difference operator, and assess the performance of the autoregressive...... for, among others, Climate Econometrics and Financial Econometrics models dealing with long memory series at different forecast horizons. We show in an example that while a short memory autoregressive moving average (ARMA) model gives the best performance when forecasting the Realized Variance...... fractionally integrated moving average (ARFIMA) model when forecasting series with long memory generated by nonfractional processes. We find that high-order autoregressive (AR) models produce similar or superior forecast performance than ARFIMA models at short horizons. Nonetheless, as the forecast horizon...

  12. Nitrate retention capacity of milldam-impacted legacy sediments and relict A horizon soils

    Directory of Open Access Journals (Sweden)

    J. N. Weitzman

    2017-05-01

    Full Text Available While eutrophication is often attributed to contemporary nutrient pollution, there is growing evidence that past practices, like the accumulation of legacy sediment behind historic milldams, are also important. Given their prevalence, there is a critical need to understand how N flows through, and is retained in, legacy sediments to improve predictions and management of N transport from uplands to streams in the context of climatic variability and land-use change. Our goal was to determine how nitrate (NO3− is cycled through the soil of a legacy-sediment-strewn stream before and after soil drying. We extracted 10.16 cm radius intact soil columns that extended 30 cm into each of the three significant soil horizons at Big Spring Run (BSR in Lancaster, Pennsylvania: surface legacy sediment characterized by a newly developing mineral A horizon soil, mid-layer legacy sediment consisting of mineral B horizon soil and a dark, organic-rich, buried relict A horizon soil. Columns were first preincubated at field capacity and then isotopically labeled nitrate (15NO3− was added and allowed to drain to estimate retention. The columns were then air-dried and subsequently rewet with N-free water and allowed to drain to quantify the drought-induced loss of 15NO3− from the different horizons. We found the highest initial 15N retention in the mid-layer legacy sediment (17 ± 4 % and buried relict A soil (14 ± 3 % horizons, with significantly lower retention in the surface legacy sediment (6 ± 1 % horizon. As expected, rewetting dry soil resulted in 15N losses in all horizons, with the greatest losses in the buried relict A horizon soil, followed by the mid-layer legacy sediment and surface legacy sediment horizons. The 15N remaining in the soil following the post-drought leaching was highest in the mid-layer legacy sediment, intermediate in the surface legacy sediment, and lowest in the buried relict A horizon soil. Fluctuations

  13. Modeling of leachate recirculation using combined drainage blanket-horizontal trench systems in bioreactor landfills.

    Science.gov (United States)

    Feng, Shi-Jin; Cao, Ben-Yi; Xie, Hai-Jian

    2017-10-01

    Leachate recirculation in municipal solid waste (MSW) landfills operated as bioreactors offers significant economic and environmental benefits. Combined drainage blanket (DB)-horizontal trench (HT) systems can be an alternative to single conventional recirculation approaches and can have competitive advantages. The key objectives of this study are to investigate combined drainage blanket -horizontal trench systems, to analyze the effects of applying two recirculation systems on the leachate migration in landfills, and to estimate some key design parameters (e.g., the steady-state flow rate, the influence width, and the cumulative leachate volume). It was determined that an effective recirculation model should consist of a moderate horizontal trench injection pressure head and supplementary leachate recirculated through drainage blanket, with an objective of increasing the horizontal unsaturated hydraulic conductivity and thereby allowing more leachate to flow from the horizontal trench system in a horizontal direction. In addition, design charts for engineering application were established using a dimensionless variable formulation.

  14. Bacterial Growth on Photochemically Transformed Leachates from Aquatic and Terrestrial Primary Producers

    DEFF Research Database (Denmark)

    Anesio, A.M.; Nielsen, Jon Theil; Granéli, W.

    2000-01-01

    We measured bacterial growth on phototransformed dissolved organic matter (DOM) leached from eight different primary producers. Leachates (10 mg C liter-1) were exposed to artificial UVA + UVB radiation, or kept in darkness, for 20 h. DOM solutions were subsequently inoculated with lake water...... on leachate and type of bacterial growth criterion. Bacterial carbon utilization (biomass production plus respiration) over the entire incubation period (120 h) was enhanced by UV radiation of leachate from the terrestrial leaves, relative to carbon utilization in non-irradiated leachates. Conversely, carbon...... utilization was reduced by radiation of the leachates from aquatic macrophytes. In a separate experiment, the stable C and N isotope composition of bacteria grown on irradiated and non-irradiated DOM was estimated. Bacterial growth on UV-irradiated DOM was enriched in 13C relative to the bacteria in the non...

  15. Detailed ocean current maps may lie over the horizon

    Science.gov (United States)

    Carlowicz, Michael

    In another case of military swords being turned into scientific plowshares, two American researchers have used radar systems once designed to detect Soviet planes during the Cold War to map open-ocean currents instead.In the name of science, Thomas Georges and Jack Harlan of NOAA's Environmental Technology Laboratory borrowed some time last summer on the U.S. Navy's over-the-horizon (OTH) radar systems in both Virginia and Texas. Training the radars on the waters off of the southern coast of Florida, the researchers gathered enough data to deduce the surface motion of two 70,000 km2 swatches of the Caribbean Sea and Gulf of Mexico. By bouncing 5-28 MHz radio waves off the ionosphere down to the sea surface and back, the researchers were able to derive the characteristics of the ocean surface from Bragg backscatter resonance.

  16. Noncommutative FRW Apparent Horizon and Hawking Radiation

    Science.gov (United States)

    Bouhallouf, H.; Mebarki, N.; Aissaoui, H.

    2017-11-01

    In the context of noncommutative (NCG) gauge gravity, and using a cosmic time power law formula for the scale factor, a Friedman-Robertson-Walker (FRW) like metric is obtained. Within the fermions tunneling effect approach and depending on the various intervals of the power parameter, expressions of the apparent horizon are also derived. It is shown that in some regions of the parameter space, a pure NCG trapped horizon does exist leading to new interpretation of the role played by the noncommutativity of the space-time.

  17. North Rim of Endeavour Crater on Horizon

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] A northern portion of the rim of Endeavour Crater is visible on the horizon of this image taken by the panoramic camera (Pancam) on NASA's Mars Exploration Rover Opportunity on March 7, 2009, during the 1,820st Martian day, or sol, of the rover's mission on Mars. That portion of Endeavour's rim is about 20 kilometers (12 miles) away from Opportunity's position west of the crater when the image was taken. The width of the image covers approximately one degree of the horizon.

  18. East Rim of Endeavour Crater on Horizon

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] A high point on the distant eastern rim of Endeavour Crater is visible on the horizon in this image taken by the panoramic camera (Pancam) on NASA's Mars Exploration Rover Opportunity on March 8, 2009, during the 1,821st Martian day, or sol, of the rover's mission on Mars. That portion of Endeavour's rim is about 34 kilometers (21 miles) away from Opportunity's position west of the crater when the image was taken. The width of the image covers approximately one degree of the horizon.

  19. Hair-brane ideas on the horizon

    International Nuclear Information System (INIS)

    Martinec, Emil J.; Niehoff, Ben E.

    2015-01-01

    We continue an examination of the microstate geometries program begun in arXiv:1409.6017, focussing on the role of branes that wrap the cycles which degenerate when a throat in the geometry deepens and a horizon forms. An associated quiver quantum mechanical model of minimally wrapped branes exhibits a non-negligible fraction of the gravitational entropy, which scales correctly as a function of the charges. The results suggest a picture of AdS 3 /CFT 2 duality wherein the long string that accounts for BTZ black hole entropy in the CFT description, can also be seen to inhabit the horizon of BPS black holes on the gravity side.

  20. Expanding your horizons in science and mathematics

    Science.gov (United States)

    1985-01-01

    Through the presentation of its Expanding Your Horizons in Science and Mathematics career education conferences for secondary school young women, the Math/Science Network continues its efforts to remove the educational, psychological, and cultural barriers which prevent women from entering math-and science-based careers. The Expanding Your Horizons conferences were presented on 77 college, university and high school campuses across the United States. This year, these unique one day conferences reached 15,500 students, 3,000 parents and educators, and involved 3,000 career women who volunteered their services as conference planners, workshop leaders, speakers, and role models.

  1. Artificial sweeteners as potential tracers of municipal landfill leachate.

    Science.gov (United States)

    Roy, James W; Van Stempvoort, Dale R; Bickerton, Greg

    2014-01-01

    Artificial sweeteners are gaining acceptance as tracers of human wastewater in the environment. The 3 artificial sweeteners analyzed in this study were detected in leachate or leachate-impacted groundwater at levels comparable to those of untreated wastewater at 14 of 15 municipal landfill sites tested, including several closed for >50 years. Saccharin was the dominant sweetener in old (pre-1990) landfills, while newer landfills were dominated by saccharin and acesulfame (introduced 2 decades ago; dominant in wastewater). Cyclamate was also detected, but less frequently. A case study at one site illustrates the use of artificial sweeteners to identify a landfill-impacted groundwater plume discharging to a stream. The study results suggest that artificial sweeteners can be useful tracers for current and legacy landfill contamination, with relative abundances of the sweeteners potentially providing diagnostic ability to distinguish different landfills or landfill cells, including crude age-dating, and to distinguish landfill and wastewater sources. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  2. Radiation decomposition of humic substances in landfill disposal leachate

    International Nuclear Information System (INIS)

    Sawai, Takeshi; Sawai, Teruko; Shimokawa, Toshinari

    1979-01-01

    The leachate generated from landfill contains humic substances such as humic acid and fluvic acid. It shows, in general, high chemical oxygen demand (COD) and biological oxygen demand (BOD), and colors in dark brown. When the leachate collected on the No. 15 landfill in Tokyo Bay was irradiated by γ-rays from a 60 Co source in bubbling air, the total organic carbon (TOC) decreased with increasing dose and the brown color was bleached. The effects of pH, flow rate, and dose rate on the decrease of TOC, the variations of UV spectrum, and the formation of carbon dioxide by the irradiation were examined. The decreasing rate of TOC increased with an increase of the flow rate up to -- 11/min and showed a maximum value in the region of pH 4 - 6. It was also dependent on the dose rate and increased with a decrease of the dose rate. The radiation chemical yield, G(-TOC), reached 162 at low dose rate of 1.3 x 10 4 rad/h. This result suggests that a radiation-induced chain reaction occurred. The amount of TOC decreased was almost equal to that of carbon dioxide formed. This result shows that the organic substances were decomposed by irradiation to carbon dioxide as a final product and it was ejected from the solution. (author)

  3. Classification of Near-Horizon Geometries of Extremal Black Holes.

    Science.gov (United States)

    Kunduri, Hari K; Lucietti, James

    2013-01-01

    Any spacetime containing a degenerate Killing horizon, such as an extremal black hole, possesses a well-defined notion of a near-horizon geometry. We review such near-horizon geometry solutions in a variety of dimensions and theories in a unified manner. We discuss various general results including horizon topology and near-horizon symmetry enhancement. We also discuss the status of the classification of near-horizon geometries in theories ranging from vacuum gravity to Einstein-Maxwell theory and supergravity theories. Finally, we discuss applications to the classification of extremal black holes and various related topics. Several new results are presented and open problems are highlighted throughout.

  4. Event horizons in the Polarizable Vacuum Model

    CERN Document Server

    Desiato, J T

    2003-01-01

    The Polarizable Vacuum (PV) Model representation of General Relativity (GR) is used to show that an in-falling particle of matter will reach the central mass object in a finite amount of proper time, as measured along the world line of the particle, when using the PV Metric. It is shown that the in-falling particle passes through an event horizon, analogous to that found in the Schwarzschild solution of GR. Once it passes through this horizon, any light signal emitted outward by the in-falling particle will be moving slower than the in-falling particle, due to the reduced speed of light in this region. Therefore the signal can never escape this horizon. However, the light emitted by a stationary object below the horizon is exponentially red-shifted and can escape along the null geodesics, as was originally predicted by the PV Model. A static, non-rotating charge distribution is added to the central mass and the PV equivalent to the Reissner-Nordstrom metric is derived. It is illustrated that the dipole moment...

  5. The NMC Horizon Report: 2013 Museum Edition

    Science.gov (United States)

    Johnson, L.; Adams Becker, S.; Freeman, A.

    2013-01-01

    The "NMC Horizon Report: 2013 Museum Edition," is a co-production with the Marcus Institute for Digital Education in the Arts (MIDEA), and examines six emerging technologies for their potential impact on and use in education and interpretation within the museum environment: BYOD (Bring Your Own Device), crowdsourcing, electronic…

  6. Agriculture’s Ethical Horizon, book review

    Science.gov (United States)

    Roughly 6.5 billion people inhabit the earth, but over 1 billion people regularly go hungry. This food shortfall poses an ethical dilemma for agriculture, and Agriculture's Ethical Horizon grapples with this dilemma. It argues that agricultural productivity has been the quintessential value of agr...

  7. Studying the cosmological apparent horizon with quasistatic ...

    Indian Academy of Sciences (India)

    dimensional Friedmann–Lemaître–Robertson–Walker (FLRW) Universe. After demonstrating a no-go theorem, we put forward the quasistatic coordinates for the FLRW Universe. Then, the quasistatic coordinates are utilized to study the unified first law and the scalar-type perturbations on the cosmological apparent horizon.

  8. Moving Horizon Estimation on a Chip

    Science.gov (United States)

    2014-06-26

    D.Q. Mayne . Constrained state estimation for nonlinear discrete-time systems: Stability and moving horizon approximations. Automatic Control, IEEE...factor of fixed-point design [11] Christopher V Rao, James B Rawlings, and David Q Mayne . Constrained state estimation for nonlinear discrete-time

  9. Falling through the black hole horizon

    International Nuclear Information System (INIS)

    Brustein, Ram; Medved, A.J.M.

    2015-01-01

    We consider the fate of a small classical object, a “stick”, as it falls through the horizon of a large black hole (BH). Classically, the equivalence principle dictates that the stick is affected by small tidal forces, and Hawking’s quantum-mechanical model of BH evaporation makes essentially the same prediction. If, on the other hand, the BH horizon is surrounded by a “firewall”, the stick will be consumed as it falls through. We have recently extended Hawking’s model by taking into account the quantum fluctuations of the geometry and the classical back-reaction of the emitted particles. Here, we calculate the strain exerted on the falling stick for our model. The strain depends on the near-horizon state of the Hawking pairs. We find that, after the Page time when the state of the pairs deviates significantly from maximal entanglement (as required by unitarity), the induced strain in our semiclassical model is still parametrically small. This is because the number of the disentangled pairs is parametrically smaller than the BH entropy. A firewall does, however, appear if the number of disentangled pairs near the horizon is of order of the BH entropy, as implicitly assumed in previous discussions in the literature.

  10. Expanding Your Horizons Conference in Geneva

    CERN Multimedia

    Chromek-Burckhart, Doris

    2011-01-01

    CERN and its experiments participated in Expanding Your Horizons (EYH) in Science and Mathematics conference in Geneva on 12th November. EYH nurture girls' interest in science and math courses to encourage them to consider careers in science, technology, engineering, and math.

  11. Sighting Horizons of Teaching in Higher Education

    Science.gov (United States)

    Barnett, Ronald; Guzmán-Valenzuela, Carolina

    2017-01-01

    This conceptual paper tackles the matter of teaching in higher education and proposes a concept of "horizons of teaching." It firstly offers an overview of the considerable empirical literature around teaching--especially conceptions of teaching, approaches to teaching and teaching practices--and goes on to pose some philosophical and…

  12. The effect of moisture content on the thermal conductivity of moss and organic soil horizons from black spruce ecosystems in interior Alaska

    Science.gov (United States)

    Jonathan A. O' Donnell; Vladimir E. Romanovsky; Jennifer W. Harden; A. David. McGuire

    2009-01-01

    Organic soil horizons function as important controls on the thermal state of near-surface soil and permafrost in high-latitude ecosystems. The thermal conductivity of organic horizons is typically lower than mineral soils and is closely linked to moisture content, bulk density, and water phase. In this study, we examined the relationship between thermal conductivity...

  13. Structure of diagnostics horizons and humus classification

    Directory of Open Access Journals (Sweden)

    Zanella A

    2008-03-01

    Full Text Available The classification of the main humus forms is generally based on the morpho-genetic characters of the A and OH diagnostic horizons. This is the case in the new European key of classification presented in Freiburg on September 2004 (Eurosoil Congress. Among the morpho-genetic characters, the soil structure covers a very important role. In this work, the structure of the diagnostic A and OH horizons has been analysed in terms of aggregation force, diameter and composition of the soil lumps (peds. In order to study the aggregation force, two disaggregating tools have been conceived and used. The diameter of the lumps has been measured by sieving the soil samples with standardised webs. Observing the samples thanks to a binocular magnifying 10X and 50X, the organic or/and mineral composition of the soil aggregates has been determined, data being investigated with ANOVA and Factorial Analysis. The article examines the argument from two points of view: crashing tools for estimating the soil structure (part 1 and the dimensions of the peds given in European key of humus forms classification (part 2. The categories of soil peds diameter and composition seem to be linked to the main humus forms. For instance, aggregates having a diamater larger than 1 mm and well amalgamate organo-mineral composition are more present in the A horizons of the Mull forms than in which of the other forms; contrary to the OH horizon of the Moder or Mor, the OH horizon of the Amphi forms shows an important percent of small organic lumps. Some propositions have been given in order to improve the European key of humus forms classification.

  14. Deepwater Horizon Seafood Safety Response - Deepwater Horizon Oil Spill Seafood Safety Response

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In the aftermath of the Deepwater Horizon oil spill in 2010, there was concern about the risk to human health through consumption of contaminated seafood from the...

  15. What happens at the horizon(s) of an extreme black hole?

    International Nuclear Information System (INIS)

    Murata, Keiju; Reall, Harvey S; Tanahashi, Norihiro

    2013-01-01

    A massless scalar field exhibits an instability at the event horizon of an extreme black hole. We study numerically the nonlinear evolution of this instability for spherically symmetric perturbations of an extreme Reissner–Nordstrom (RN) black hole. We find that generically the endpoint of the instability is a non-extreme RN solution. However, there exist fine-tuned initial perturbations for which the instability never decays. In this case, the perturbed spacetime describes a time-dependent extreme black hole. Such solutions settle down to extreme RN outside, but not on, the event horizon. The event horizon remains smooth but certain observers who cross it at late time experience large gradients there. Our results indicate that these dynamical extreme black holes admit a C 1 extension across an inner (Cauchy) horizon. (paper)

  16. Toxicity of tire wear particle leachate to the marine macroalga, Ulva lactuca

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Andrew, E-mail: aturner@plymouth.ac.u [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Rice, Lynsey [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

    2010-12-15

    Tire wear particles filed from the treads of end-of-life vehicle tires have been added to sea water to examine the release of Zn and the toxicity of the resulting leachate and dilutions thereof to the marine macroalga, Ulva lactuca. Zinc release appeared to be diffusion-controlled, with a conditional rate constant of 5.4 {mu}g[L(h){sup 1/2}]{sup -1}, and about 1.6% of total Zn was released after 120 h incubation. Exposure to increasing concentrations of leachate resulted in a non-linear reduction in the efficiency of photochemical energy conversion of U. lactuca and, with the exception of the undiluted leachate, increasing accumulation of Zn. Phototoxicity was significantly lower on exposure to equivalent concentrations of Zn added as Zn(NO{sub 3}){sub 2}, suggesting that organic components of leachate are largely responsible for the overall toxicity to the alga. Given the ubiquity and abundance of TWP in urban coastal sediments, the generation, biogeochemistry and toxicity of tire leachate in the marine setting merit further attention. - Tire wear leachate is toxic to Ulva lactuca and zinc is a potential bioindicator of leachate contamination in urban marine systems.

  17. Evolution of nitrogen species in landfill leachates under various stabilization states.

    Science.gov (United States)

    Zhao, Renzun; Gupta, Abhinav; Novak, John T; Goldsmith, C Douglas

    2017-11-01

    In this study, nitrogen species in landfill leachates under various stabilization states were investigated with emphasis on organic nitrogen. Ammonium nitrogen was found to be approximately 1300mg/L in leachates from younger landfill units (less than 10years old), and approximately 500mg/L in leachates from older landfill units (up to 30years old). The concentration and aerobic biodegradability of organic nitrogen decreased with landfill age. A size distribution study showed that most organic nitrogen in landfill leachates is nitrogen (TON, mg/L-N, R 2 =0.88 and 0.98 for untreated and treated samples, respectively). The slopes of the regression curves of untreated (protein=0.45TON) and treated (protein=0.31TON) leachates indicated that the protein is more biodegradable than the other organic nitrogen species in landfill leachates. XAD-8 resin was employed to isolate the hydrophilic fraction of leachate samples, and it was found that the hydrophilic fraction proportion in terms of organic nitrogen decreased with landfill age. Solid-state 15 N nuclear magnetic resonance (NMR) was utilized to identify the nitrogen species. Proteinaceous materials were found to be readily biodegradable, while heterocyclic nitrogen species were found to be resistant to biodegradation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Characteristics of Leachate and Their Effect on Shallow Groundwater Quality (Case Study : TPA Cipayung, Depok)

    Science.gov (United States)

    Widiastuti, Atika; Hartono, Djoko M.; Moersidik, Setyo S.; Gusniani, Irma

    2018-03-01

    The problems arising from landfill activity is leaked leachate that is not absorbed well into leachate stabilization pond which furthermore contaminates shallow groundwater around landfill, include Cipayung landfill. The aims of this study is to determine the characteristics of leachate and their effect on shallow groundwater quality around landfill based on temperature, pH, Total Suspended Solids (TSS), Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Nitrogen (TN), Mercury (Hg), and fecal coliform. Data were analyzed based on leachate samples at influent point, effluent point, and 7 sampling points of residents’s well with distance variation every 100 meters within 300 meters radius having leachate stabilization pond as benchmark. According to the standard of Indonesia’s Ministry of Environment and Forestry law No. 59 of 2016, the results showed that leachate quality was still above the standard of BOD, COD, and Total Nitrogen parameters; 4178.0 mg/L, 70556.0 mg/L and 373.3 mg/L for influent point, and 3142.0 mg/L, 9055.2 mg/L, and 350 mg/L for the effluent point. Pollution Index of shallow groundwater is between lightly and moderately contaminated. This study showed that the further the distance between sampling point and leachate stabilization pond is, the lower the Polution Index is.

  19. Anaerobic co-digestion of food waste and landfill leachate in single-phase batch reactors

    International Nuclear Information System (INIS)

    Liao, Xiaofeng; Zhu, Shuangyan; Zhong, Delai; Zhu, Jingping; Liao, Li

    2014-01-01

    Highlights: • Anaerobic co-digestion strategy for food waste treatment at OLR 41.8 g VS/L. • A certain amount of raw leachate effectively relieved acidic inhibition. • The study showed that food waste was completely degraded. - Abstract: In order to investigate the effect of raw leachate on anaerobic digestion of food waste, co-digestions of food waste with raw leachate were carried out. A series of single-phase batch mesophilic (35 ± 1 °C) anaerobic digestions were performed at a food waste concentration of 41.8 g VS/L. The results showed that inhibition of biogas production by volatile fatty acids (VFA) occurred without raw leachate addition. A certain amount of raw leachate in the reactors effectively relieved acidic inhibition caused by VFA accumulation, and the system maintained stable with methane yield of 369–466 mL/g VS. Total ammonia nitrogen introduced into the digestion systems with initial 2000–3000 mgNH 4 –N/L not only replenished nitrogen for bacterial growth, but also formed a buffer system with VFA to maintain a delicate biochemical balance between the acidogenic and methanogenic microorganisms. UV spectroscopy and fluorescence excitation–emission matrix spectroscopy data showed that food waste was completely degraded. We concluded that using raw leachate for supplement water addition and pH modifier on anaerobic digestion of food waste was effective. An appropriate fraction of leachate could stimulate methanogenic activity and enhance biogas production

  20. Leachate Properties and Cadmium Migration Through Freeze-thaw Treated Soil Columns.

    Science.gov (United States)

    Xu, Meng; Zheng, Yue; Chen, Weiwei; Mao, Na; Guo, Ping

    2017-01-01

    Soil column leaching experiments were conducted to study the effects of multiple freeze-thaw cycles on the vertical migration of cadmium (Cd). Three Cd-spiked leaching solutions of different properties were derived from snowmelt, sludge, and straw, designated as B, W and J, respectively. The leaching solutions varied in dissolved organic matter (DOM) concentrations in the order of J > W > B. Changes in leachate properties and Cd concentration were observed. The results showed that pH values of all the leachate solutions through freeze-thaw treated soil columns were higher than those of leachates through unfrozen soils. However, electrical conductivity (EC) values decreased compared with leachates in unfrozen treated soil columns. Although the concentrations of DOM in leachate solutions had no evident differences between the freeze-thaw and unfrozen treated soil columns, the concentrations of DOM in the leachate solutions B, W and J were different. Freeze-thaw cycles resulted in increased concentrations of Cd in the leachate solutions in the order J > W > B, and promoted a deeper migration of Cd in the soil columns. Thus, it was shown that freeze-thaw cycles may increase the risk of groundwater pollution by Cd.

  1. Optimizing the treatment of landfill leachate by conventional Fenton and photo-Fenton processes

    International Nuclear Information System (INIS)

    Hermosilla, Daphne; Cortijo, Manuel; Huang, Chin Pao

    2009-01-01

    Landfill, a matured and economically appealing technology, is the ultimate approach for the management of municipal solid wastes. However, the inevitable generation of leachate from landfill requires further treatment. Among the various leachate treatment technologies available, advanced oxidation processes (AOPs) are among powerful methods to deal with the refractory organic constituents, and the Fenton reagent has evolved as one promising AOPs for the treatment of leachates. Particularly, the combination of UV-radiation with Fenton's reagent has been reported to be a method that allows both the photo-regeneration of Fe 2+ and photo-decarboxylation of ferric carboxylates. In this study, Fenton and photo-Fenton processes were fine tuned for the treatment of leachates from the Colmenar Viejo (Madrid, Spain) Landfill. Results showed that it is possible to define a set of conditions under which the same COD and TOC removals (approx 70%) could be achieved with both the conventional and photo-Fenton processes. But Fenton process generated an important quantity of iron sludge, which will require further disposal, when performed under optimal COD removal conditions. Furthermore conventional Fenton process was able to achieve slightly over an 80% COD removal from a 'young' leachate, while for 'old' and 'mixed' leachates was close to a 70%. The main advantage showed by the photo-assisted Fenton treatment of landfill leachate was that it consumed 32 times less iron and produced 25 times less sludge volume yielding the same COD removal results than a conventional Fenton treatment.

  2. Acceleration of a Static Observer Near the Event Horizon of a Static Isolated Black Hole.

    Science.gov (United States)

    Doughty, Noel A.

    1981-01-01

    Compares the magnitude of the proper acceleration of a static observer in a static, isolated, spherically symmetric space-time region with the Newtonian result including the situation in the interior of a perfect-fluid star. This provides a simple physical interpretation of surface gravity and illustrates the global nature of the event horizon.…

  3. The Small Satellites of Pluto as Observed by New Horizons

    Science.gov (United States)

    Weaver, H. A.; Buie, M. W; Buratti, B. J.; Grundy, W. M.; Lauer, T. R.; Olkin, C. B.; Parker, A .H.; Porter, S. B.; Showalter, M. R.; Spencer, J. R.; hide

    2016-01-01

    The New Horizons mission has provided resolved measurements of Pluto's moons Styx, Nix, Kerberos, and Hydra. All four are small, with equivalent spherical diameters of approx.40 kilometers for Nix and Hydra and approx. 10 kilometers for Styx and Kerberos. They are also highly elongated, with maximum to minimum axis ratios of approx. 2. All four moons have high albedos (approx.50 to 90%) suggestive of a water-ice surface composition. Crater densities on Nix and Hydra imply surface ages of at least 4 billion years. The small moons rotate much faster than synchronous, with rotational poles clustered nearly orthogonal to the common pole directions of Pluto and Charon. These results reinforce the hypothesis that the small moons formed in the aftermath of a collision that produced the Pluto-Charon binary.

  4. Alteration of Gills and Liver Histological Structure of Cyprinus carpio Exposed to Leachate

    Directory of Open Access Journals (Sweden)

    Tri Dewi Kusumaningrum Pribadi

    2017-07-01

    Full Text Available One of the main problems in the waste management in Indonesia is the treatment of leachate, which mostly dumped to the river This research is aimed to obtain information of histological alteration in gills and liver of C. carpio L. exposed to leachate. Measurements on the water quality parameters comprised water temperature, pH, and dissolved oxygen (DO. This research was conducted by exposing leachate to C. carpio for 96 hours. The concentration of leachate were 0 ppm, 80 ppm, and 100 ppm. Histological preparation were made on the gills and liver using 10% fixative Neutral Buffered Formalin and Ehrlich Hematoxylin-Eosin staining with qualitative observation descriptive analyses for discussion. The result showed that increasing water temperature is directly proportional to the leachate concentration in the aquaria, while the value of pH and DO inversely proportional to the leachate concentration. Damages on the gills with 80 ppm leachate concentrasion were identified as follows: fusion of secondary gill filaments and hyperplasia of epithelial cell, along with karyorrhexis and hydropic degeneration on the liver. Damages on the gills of fishes exposed to leachate with 100 ppm concentrasion were identified as follows: fusion of secondary gill filaments, hyperplasia of epithelial cell, congestion, and edema along with karyorrhexis, hydropic degeneration and melanomacrophage centre (MMC found on the liver. The results of this study can be used as an overview of the impact of an environmental pollution by leachate as indicated from histological damage to the gills and liver of C. carpio, thus contribute significan information to aquaculture sector and endorse better waste management

  5. Review on landfill leachate treatment by electrochemical oxidation: Drawbacks, challenges and future scope.

    Science.gov (United States)

    Mandal, Pubali; Dubey, Brajesh K; Gupta, Ashok K

    2017-11-01

    Various studies on landfill leachate treatment by electrochemical oxidation have indicated that this process can effectively reduce two major pollutants present in landfill leachate; organic matter and ammonium nitrogen. In addition, the process is able to enhance the biodegradability index (BOD/COD) of landfill leachate, which make mature or stabilized landfill leachate suitable for biological treatment. The elevated concentration of ammonium nitrogen especially observed in bioreactor landfill leachate can also be reduced by electrochemical oxidation. The pollutant removal efficiency of the system depends upon the mechanism of oxidation (direct or indirect oxidation) which depends upon the property of anode material. Applied current density, pH, type and concentration of electrolyte, inter-electrode gap, mass transfer mode, total anode area to volume of effluent to be treated ratio, temperature, flow rate or flow velocity, reactor geometry, cathode material and lamp power during photoelectrochemical oxidation may also influence the system performance. In this review paper, past and present scenarios of landfill leachate treatment efficiencies and costs of various lab scale, pilot scale electrochemical oxidation studies asa standalone system or integrated with biological and physicochemical processes have been reviewed with the conclusion that electrochemical oxidation can be employed asa complementary treatment system with biological process for conventional landfill leachate treatment as well asa standalone system for ammonium nitrogen removal from bioreactor landfill leachate. Furthermore, present drawbacks of electrochemical oxidation process asa landfill leachate treatment system and relevance of incorporating life cycle assessment into the decision-making process besides process efficiency and cost, have been discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Longitudinal data analysis in support of functional stability concepts for leachate management at closed municipal landfills

    International Nuclear Information System (INIS)

    Gibbons, Robert D.; Morris, Jeremy W.F.; Prucha, Christopher P.; Caldwell, Michael D.; Staley, Bryan F.

    2014-01-01

    Highlights: • Longitudinal data analysis using a mixed-effects regression model. • Dataset consisted of a total of 1402 samples from 101 closed municipal landfills. • Target analytes and classes generally showed predictable degradation trends. • Validates historical studies focused on macro organic indicators such as BOD. • BOD can serve as “gateway” indicator for planning leachate management. - Abstract: Landfill functional stability provides a target that supports no environmental threat at the relevant point of exposure in the absence of active control systems. With respect to leachate management, this study investigates “gateway” indicators for functional stability in terms of the predictability of leachate characteristics, and thus potential threat to water quality posed by leachate emissions. Historical studies conducted on changes in municipal solid waste (MSW) leachate concentrations over time (longitudinal analysis) have concentrated on indicator compounds, primarily chemical oxygen demand (COD) and biochemical oxygen demand (BOD). However, validation of these studies using an expanded database and larger constituent sets has not been performed. This study evaluated leachate data using a mixed-effects regression model to determine the extent to which leachate constituent degradation can be predicted based on waste age or operational practices. The final dataset analyzed consisted of a total of 1402 samples from 101 MSW landfills. Results from the study indicated that all leachate constituents exhibit a decreasing trend with time in the post-closure period, with 16 of the 25 target analytes and aggregate classes exhibiting a statistically significant trend consistent with well-studied indicators such as BOD. Decreasing trends in BOD concentration after landfill closure can thus be considered representative of trends for many leachate constituents of concern

  7. PENURUNAN KANDUNGAN LOGAM PB DAN CR LEACHATE MELALUI FITOREMEDIASI BAMBU AIR (EQUISETUM HYEMALE DAN ZEOLIT

    Directory of Open Access Journals (Sweden)

    Bambang Suharto

    2016-11-01

    Full Text Available The very large numbers of trash in the TPA (end disposal place will cause the natural decomposition process goes on massively as well. The decomposition process will change trash into organic fertilizer that if there any water input from the outside, it will dissolve metals that later become the byproduct that is leachate. The introduction of chemical contained in the leachate into the waters ecosystem may also affect the existing biota. Therefore, it is need the waste treatment before released into the environment. Leachate waste treatment by using the phytoremediation principle by means of Bambu air plant (Equisetum hyemale, with zeolite planting media was to be the choice in the effort of liquid waste treatment the Phytoremediation system was taken with a various considerations that very potential to develop into new innovation in the process of leachate waste treatment.This research had the purpose to know the effectiveness of phytoremediation system using water bamboo plant (Equisetum hyemale and zeolit planting media by batch system and continue system in reducing Pb and Cr heavy metals contents of leachate. Research method used was the experimental method. Observations carried out involved environmental temperature and humidity, solution pH and treatment temperature, Reduction of Pb and Cr Metals Contents on leachate.Batch system and continue system as a whole, mean of leachate pH tested during this treatment was about 7,466. Leachate pH tested did not less than 7,200 and not more that 7,810. Mean of leachate temperature from the first week through third week was of 22,283°C. The best treatment was on the K­2S1 (60 batch system plants treatment with reduction of Pb metal content of 82,2% in the last week of observation. While the reduction of Cr metal of 61,2% was on the K2S2 (60 continue system plants treatment.

  8. Characterization of rock samples and mineralogical controls on leachates

    Science.gov (United States)

    Hammarstrom, Jane M.; Cravotta, Charles A.; Galeone, Daniel G.; Jackson, John C.; Dulong, Frank T.; Hornberger, Roger J.; Brady, Keith B.C.

    2009-01-01

    post-weathering rock samples, report trace-element content in leachate, and discuss mineralogical controls on leachate quality based on data from one of the participating laboratories. Table 5.1 lists the samples described in this chapter, the sample numbers, and comments on the characteristics of each lithology. Sample locations are plotted in Figure 5.1. Chapters 2 and 3 describe the sample locations, sample preparation protocols, ABA characteristics, and rationale for selection of rock samples for testing. Microprobe data for pyrite and carbonate minerals are tabulated in Appendix 5.1. Leachate data, along with a series of graphs showing concentration and cumulative transport trends, for the laboratory data discussed in this chapter are included as Excel spreadsheets in Appendices 5.2 and 5.3. Leach column data for the interlaboratory study are evaluated and interpreted in Chapters 7 -11.

  9. Phase space and black-hole entropy of higher genus horizons in loop quantum gravity

    International Nuclear Information System (INIS)

    Kloster, S; Brannlund, J; DeBenedictis, A

    2008-01-01

    In the context of loop quantum gravity, we construct the phase space of isolated horizons with genus greater than 0. Within the loop quantum gravity framework, these horizons are described by genus g surfaces with N punctures and the dimension of the corresponding phase space is calculated including the genus cycles as degrees of freedom. From this, the black-hole entropy can be calculated by counting the microstates which correspond to a black hole of fixed area. We find that the leading term agrees with the A/4 law and that the sub-leading contribution is modified by the genus cycles

  10. Natural attenuation processes in landfill leachate plumes at three Danish sites

    DEFF Research Database (Denmark)

    Bjerg, Poul Løgstrup; Tuxen, Nina; Reitzel, Lotte

    2011-01-01

    . The research performed serves as good case studies to conceptualize natural attenuation processes in landfill leachate plumes and also supports the notion that monitored natural attenuation (MNA) may be a possible remediation strategy at landfills. However, landfill leachate plumes challenge traditional......This article provides an overview of comprehensive core and fringe field studies at three Danish landfill sites. The goal of the research activities is to provide a holistic description of core and fringe attenuation processes for xenobiotic organic compounds in landfill leachate plumes...

  11. Mono- and diesters from o-phthalic acid in leachates from different European landfills

    DEFF Research Database (Denmark)

    Jonsson, S.; Eilertsson, J.; Ledin, Anna

    2003-01-01

    Leachates from 17 different landfills in Europe were, analysed with respect to phthalates, i.e. phthalic acid diesters (PAEs) and their degradation products phthalic acid monoesters (PMEs) and ortho-phthalic acid (PA). Diesters are ubiquitous and the human possible exposure and potential to human...... health and environment has put them in focus. The aim of this study was to elucidate whether monoesters and phthalic acid could be traced in landfill leachates and in what concentrations they may be found. The results showed that phthalates were present in the majority of the leachates investigated...

  12. Ammonia removal from leachate by photochemical process using H2O2

    Directory of Open Access Journals (Sweden)

    Giovani Archanjo Brota

    2010-08-01

    Full Text Available In this work, it was studied the optimization of the photochemical process using H2O2/UV in order to reduce the concentration of ammonia in leachate. It was used landfills leachate previously treated in the development of studies. A photochemical reactor with the capacity of 1.7 liters equipped with refrigeration system and recirculation of leachate was employed in the research. The influence of temperature, the light bulb power, the concentration of H2O2 and treatment time were tested during the study. A removal of 97% of ammonia was observed at 90 min.

  13. Determination of phenols in landfill leachate-contaminated groundwaters by solid-phase extraction

    DEFF Research Database (Denmark)

    Ask Reitzel, Lotte; Ledin, Anna

    2002-01-01

    A solid-phase extraction method for phenols in landfill leachates was developed and optimized in order to solve the expected and observed problems associated with an anaerobic matrix containing high concentrations of salts and organic matter. Isolute ENV1 cartridges exhibited the best retention...... be identified in leachates from three Danish landfills, ranging in concentration from 0.01 to 29 mg/ L, which is at the lower end of the concentration range usually found for phenols in landfill leachates (sub-mg/L to mg/L).  2002 Elsevier Science B.V. All rights reserved....

  14. Hydrological classification of orthic A horizons in Weatherley, South ...

    African Journals Online (AJOL)

    Orthic A horizons carry little interpretive, especially hydrological, value. This paper aims to elucidate the hydrological interpretation of orthic A horizons. Measured water contents in the orthic A horizons of 28 profiles in the Weatherley catchment of South Africa were used to classify the topsoils into wetness classes. The very ...

  15. Infrared Limb Sounding with Cassini CIRS: Optimal Viewing Strategy Using Horizon Nodes

    Science.gov (United States)

    Mixon, Conor A.; Achterberg, Richard K.; Flasar, F. Michael

    2010-01-01

    In this paper we investigate a question of science optimization during Cassini flybys of Titan. The Composite Infrared Spectrometer (CIRS) makes limb during the closest approach period when the visible horizon circle is moving swiftly across the planet. We have sought to discover if any points on the horizon are preferred for limb sounding due to having minimum movement relative to the surface. By numerical calculation, backed by geometric analysis, we find that two limited regions on the horizon are continuously visible during the entire encounter. We term these "limb nodes" and show how they may be employed by CIRS to optimize science by minimizing the source of systematic error due to spatial smear. These conclusions are applicable to many similar scenarios of spacecraft limb sounding during hyperbolic flyby encounters.

  16. Horizons and non-local time evolution of quantum mechanical systems

    International Nuclear Information System (INIS)

    Casadio, Roberto

    2015-01-01

    According to general relativity, trapping surfaces and horizons are classical causal structures that arise in systems with sharply defined energy and corresponding gravitational radius. The latter concept can be extended to a quantum mechanical matter state simply by means of the spectral decomposition, which allows one to define an associated ''horizon wave-function''. Since this auxiliary wave-function contains crucial information about the causal structure of space-time, a new proposal is formulated for the time evolution of quantum systems in order to account for the fundamental classical property that outer observers cannot receive signals from inside a horizon. The simple case of a massive free particle at rest is used throughout the paper as a toy model to illustrate the main ideas. (orig.)

  17. Hexavalent chromium bioreduction and chemical precipitation of sulphate as a treatment of site-specific fly ash leachates.

    Science.gov (United States)

    Cason, Errol D; Williams, Peter J; Ojo, Elizabeth; Castillo, Julio; DeFlaun, Mary F; van Heerden, Esta

    2017-05-01

    Most of the power generation globally is by coal-fired power plants resulting in large stockpiles of fly ash. The trace elements associated with the ash particles are subjected to the leaching effects of precipitation which may lead to the subsequent contamination of surface and groundwater systems. In this study, we successfully demonstrate an efficient and sustainable dual treatment remediation strategy for the removal of high levels of Cr 6+ and SO 4 2- introduced by fly ash leachate generated by a power station situation in Mpumalanga, South Africa. The treatment consisted of a primary fixed-bed bioreactor kept at a reduction potential for Cr 6+ reduction. Metagenome sequencing clearly indicated a diverse bacterial community containing various bacteria, predominantly of the phylum Proteobacteria which includes numerous species known for their ability to detoxify metals such as Cr 6+ . This was followed by a secondary BaCO 3 /dispersed alkaline substrate column for SO 4 2- removal. The combination of these two systems resulted in the removal of 99% Cr 6+ and 90% SO 4 2- . This is the first effective demonstration of an integrated system combining a biological and chemical strategy for the remediation of multi-contaminants present in fly ash leachate in South Africa.

  18. EFFECT OF SULFATE LOADING RATE AND ORGANIC LOADING RATE ON ANAEROBIC BAFFLED REACTORS USED FOR TREATMENT OF SANITARY LANDFILL LEACHATES

    Directory of Open Access Journals (Sweden)

    O. Burbano-Figueroa

    2015-06-01

    Full Text Available AbstractThis study investigated the effect of organic loading rate (OLR and sulfate loading rate (SLR on landfill leachate treatment by a lab-scale anaerobic baffled reactor (ABR. Landfill leachate contained a concentration of organic matter between 3966 and 5090 mg COD.L-1 and no detectable amounts of sulfate. Reactors were started-up by feeding them with iron-sulfate at a SLR of 0.05 g SO42-.L-1.day-1 (4 weeks. Factorial design and response surface techniques were used to evaluate and optimize the effects of these operating variables on COD removal. ABRs were operated at OLRs ranging from 0.30 up to 6.84 g COD.L-1.day-1 by changes in influent volumetric flow. SO42- was added to the influent at a SRL from 0.06 to 0.13 g SO42-.L-1.day-1. The highest value of COD removal (66% was reached at an OLR of 3.58 g COD.L-1.day-1 and SLR of 0.09 g SO4-2.L-1.day-1 with a COD/SO4-2 ratio of 40. Under these conditions sulfate is mainly used for molecular hydrogen consumption while organic matter is preferentially degraded via methanogesis.

  19. Calcium and organic matter removal by carbonation process with waste incineration flue gas towards improvement of leachate biotreatment performance.

    Science.gov (United States)

    Zhang, Cheng; Zhu, Xuedong; Wu, Liang; Li, Qingtao; Liu, Jianyong; Qian, Guangren

    2017-09-01

    Municipal solid wastes incineration (MSWI) flue gas was employed as the carbon source for in-situ calcium removal from MSWI leachate. Calcium removal efficiency was 95-97% with pH of 10.0-11.0 over 100min of flue gas aeration, with both bound Ca and free Ca being removed effectively. The fluorescence intensity of tryptophan, protein-like and humic acid-like compounds increased after carbonation process. The decrease of bound Ca with the increase of precipitate indicated that calcium was mainly converted to calcium carbonate precipitate. It suggested that the interaction between dissolved organic matter and Ca 2+ was weakened. Moreover, 10-16% of chemical oxygen demand removal and the decrease of ultraviolet absorption at 254nm indicated that some organics, especially aromatic compound decreased via adsorption onto the surface of calcium carbonate. The results indicate that introduce of waste incineration flue gas could be a feasible way for calcium removal from leachate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. The 2010 Eyjafjallajökull volcanic summit eruption: evidences from ash-leachates analysis and ground deposition fluxes

    Science.gov (United States)

    Bagnato, E.; Aiuppa, A.; Bertagnini, A.; Bonadonna, C.; Cioni, R.; Pedone, M.; Pistolesi, M.

    2012-04-01

    The Eyjafjallajökull 2010 eruption was an extraordinary event in that it led to widespread over Europe. Volcanic processes which lead to eruptions can be investigated by monitoring a variety of parameters, including the composition of ash leachates. Fine-grained tephra erupted from active vents, and transported through volcanic plumes, can adsorbs, and therefore rapidly scavenge, volatile elements such as S, halogens, and metal species in the form of soluble salts adhering to ash surfaces. Analysis of such water-soluble phases is a suitable complement for the remote sensing of volcanic gases at inaccessible volcanoes, like Eyjafjallajökull. The 2010 Eyjafjallajökull eruption developed in four main phases, whose difference in gas chemistry and products has been marked in ash-leachates data too. The recurrent ash fallout provided a unique opportunity to characterize the compositional features of ash leachates, and to identify their relation (if any) with the eruptive activity styles of the volcano. By these considerations, we report on the chemical composition of leachates of 20 volcanic ash samples deposited during the most explosive Eyjafjallajökull activities (from 14 April to 8 May) and during the lava fountaining event (on 26th March 2010). We found that ash-leachate solutions are dominated - among cations - by Na and Ca, while they display nearly equal S : Cl : F abundances (mean S/Cl and S/F molar ratios of 0.85 and 0.33, respectively), as characteristic of divergent-plate and within-plate volcanism. The strong correlations between leached Ca - F , Ca - SO4, and Na - Cl (r2 = 0.7 - 0.9), suggest that fluorite, anhydrite, and halite are the most likely soluble surface minerals formed in the plume (and therefore leached during our experiments), as also reported at many active volcanoes. Our data bring evidence for variations in S and halogens proportions, with samples from 5 - 8th May which show the highest S/Cl and lowest Cl/F ratios. By combining the

  1. Leachate and radon production from fly ash autoclaved cellular concrete

    International Nuclear Information System (INIS)

    Latona, M.C.; Neufeld, R.D.; Vallejo, L.E.; Brandon, D.; Hu, W.; Kelly, C.

    1997-01-01

    Environmental consequences and potential liabilities of autoclaved cellular concrete (ACC) use were assessed by aqueous leaching of crushed samples for metals and organic solvent extractions of solid ACC for polycyclic aromatic hydrocarbons (PAHs). Also, whole ACC blocks were tested for radon exhalation potential. Results show leachate concentrations were typically 10 times below, and always 100 times below the regulatory threshold of applicable drinking water standards. A Microtox bioassay procedure showed no toxic effects due to leached metals. Organic analysis of solvent extracts indicated no release of hazardous PAHs attributable to the fly ash ingredient of ACC. Measured rates of radon exhalation were too low to cause potentially dangerous buildups in confined air spaces. Fly ash ACC may be characterized as an environmentally green construction material based on these findings

  2. Landfill leachate treatment by solar-driven AOPs

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Elisangela M.R. [Universidade Federal do Ceara, Campus do Pici, Centro de Tecnologia, Departamento de Engenharia Hidraulica e Ambiental, Laboratorio de Saneamento (LABOSAN), Avenida da Universidade, 2853 - Benfica, 60020-181 Fortaleza (Brazil); Vilar, Vitor J.P.; Boaventura, Rui A.R. [LSRE - Laboratory of Separation and Reaction Engineering, Departamento de Engenharia Quimica, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); Fonseca, Amelia; Saraiva, Isabel [Efacec Ambiente, SA, Rua Eng. Frederico Ulrich - Guardeiras, Apartado 3003, 4471-907 Moreira da Maia (Portugal)

    2011-01-15

    Sanitary landfill leachate resulting from the rainwater percolation through the landfill layers and waste material decomposition is a complex mixture of high-strength organic and inorganic compounds which constitutes serious environmental problems. In this study, different heterogeneous (TiO{sub 2}/UV, TiO{sub 2}/H{sub 2}O{sub 2}/UV) and homogenous (H{sub 2}O{sub 2}/UV, Fe{sup 2+}/H{sub 2}O{sub 2}/UV) photocatalytic processes were investigated as an alternative for the treatment of a mature landfill leachate. The addition of H{sub 2}O{sub 2} to TiO{sub 2}/UV system increased the reduction of the aromatic compounds from 15% to 61%, although mineralization was almost the same. The DOC and aromatic content abatement is similar for the H{sub 2}O{sub 2}/UV and TiO{sub 2}/H{sub 2}O{sub 2}/UV processes, although the H{sub 2}O{sub 2} consumption is three times higher in the H{sub 2}O{sub 2}/UV system. The low efficiency of TiO{sub 2}/H{sub 2}O{sub 2}/UV system is presumably due to the alkaline leachate solution, for which the H{sub 2}O{sub 2} becomes highly unstable and self-decomposition of H{sub 2}O{sub 2} occurs. The efficiency of the TiO{sub 2}/H{sub 2}O{sub 2}/UV system increased 10 times after a preliminary pH correction to 4. The photo-Fenton process is much more efficient than heterogeneous (TiO{sub 2}, TiO{sub 2}/H{sub 2}O{sub 2}/UV) or homogeneous (H{sub 2}O{sub 2}/UV) photocatalysis, showing an initial reaction rate more than 20 times higher, and leading to almost complete mineralization of the wastewater. However, when compared with TiO{sub 2}/H{sub 2}O{sub 2}/UV with acidification, the photo-Fenton reaction is only two times faster. The optimal initial iron dose for the photo-Fenton treatment of the leachate is 60 mg Fe{sup 2+} L{sup -1}, which is in agreement with path length of 5 cm in the photoreactor. The kinetic behaviour of the process (60 mg Fe{sup 2+} L{sup -1}) comprises a slow initial reaction, followed by a first-order kinetics (k = 0.020 LkJ{sub UV

  3. Some deficiencies in analyzing leachates and reporting results

    International Nuclear Information System (INIS)

    Sill, C.W.

    1980-01-01

    Determination of the leachability of elements from various radioactive waste forms for long-term retention requires chemical analysis of both the leachate and waste form. Neither the precision of the leaching procedure nor the accuracy of the results can be determined unambiguously if gross uncertainties exist. It should be demonstrated beforehand that all participating laboratories can obtain the same analytical result within some stated uncertainty. Special precautions must be taken to ensure that all material leached from the waste form is recovered from the leaching container and that all refractory particles are dissolved completely before analysis is begun. The actual results obtained should be reported, including negative signs if present, avoiding all subjective and quantitatively nondescriptive statements such as nil, none, not detected, etc. Each result must be accompanied by an estimate of its uncertainty. Problems involved in interlaboratory comparisons are discussed

  4. Simulated evapotranspiration from a landfill irrigated with landfill leachate

    International Nuclear Information System (INIS)

    Aronsson, P.

    1996-01-01

    Evapotranspiration from a landfill area, irrigated with leachate water, was simulated with the SOIL model. Three different types of vegetation (bare soil, grass ley, and willow) were used both with and without irrigation. The highest simulated evapotranspiration (604 mm) during the growing season was found from an irrigated willow stand with a high interception capacity. The lowest evapotranspiration (164 mm) was found from the bare soil. The relatively high evapotranspiration from the willow was probably caused by the high LAI (Leaf Area Index) and the low aerodynamic resistance within the willow stand. The results indicate that it is possible to reduce most of the leakage water from a landfill by irrigation of willow stands. 9 refs, 4 figs, 1 tab

  5. First evidence of fish genotoxicity induced by heavy metals from landfill leachates: the advantage of using the RAPD-PCR technique.

    Science.gov (United States)

    Ben Salem, Zohra; Capelli, Nicolas; Grisey, Elise; Baurand, Pierre-Emmanuel; Ayadi, Habib; Aleya, Lotfi

    2014-03-01

    Municipal leachates are loaded with heavy metals that can contaminate surface water before discharge into a receiving body of water. The aim of this study is to evaluate the genotoxic effects of heavy metals generated by domestic waste on the common roach Rutilus rutilus in the last of the four interconnected ponds at the Etueffont landfill. We used random amplified polymorphic DNA (RAPD) since it has been shown to be a powerful means of detecting a broad range of DNA damage due to environmental contaminants. Our results show the ability of RAPD analysis to detect significant genetic alterations in roach DNA, after contamination with a set of metals contained in the landfill leachates in comparison to a roach from a non-polluted reference pond. Analysis of electrophoresis profiles indicates apparent changes such as the appearance of new bands or disappearance of bands as compared to the control. In fact, mixed smearing and laddering of DNA fragments in muscle samples support the genotoxic effects of metal deposits in the roach. This study is the first evidence found via the RAPD-PCR technique in the detection of pollutant impacts on fish exposed to landfill leachates. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. A case study of coupling upflow anaerobic sludge blanket (UASB) and ANITA™ Mox process to treat high-strength landfill leachate.

    Science.gov (United States)

    Lu, Ting; George, Biju; Zhao, Hong; Liu, Wenjun

    2016-01-01

    A pilot study was conducted to study the treatability of high-strength landfill leachate by a combined process including upflow anaerobic sludge blanket (UASB), carbon removal (C-stage) moving bed biofilm reactor (MBBR) and ANITA™ Mox process. The major innovation on this pilot study is the patent-pending process invented by Veolia that integrates the above three unit processes with an effluent recycle stream, which not only maintains the low hydraulic retention time to enhance the treatment performance but also reduces inhibiting effect from chemicals present in the high-strength leachate. This pilot study has demonstrated that the combined process was capable of treating high-strength leachate with efficient chemical oxygen demand (COD) and nitrogen removals. The COD removal efficiency by the UASB was 93% (from 45,000 to 3,000 mg/L) at a loading rate of 10 kg/(m(3)·d). The C-stage MBBR removed an additional 500 to 1,000 mg/L of COD at a surface removal rate (SRR) of 5 g/(m(2)·d) and precipitated 400 mg/L of calcium. The total inorganic nitrogen removal efficiency by the ANITA Mox reactor was about 70% at SRR of 1.0 g/(m(2)·d).

  7. Landfills in Jiangsu province, China, and potential threats for public health: Leachate appraisal and spatial analysis using geographic information system and remote sensing

    International Nuclear Information System (INIS)

    Yang Kun; Zhou Xiaonong; Yan Weian; Hang Derong; Steinmann, Peter

    2008-01-01

    Waste disposal is of growing environmental and public health concern in China where landfilling is the predominant method of disposal. The assessment of potential health hazards posed by existing landfills requires sound information, and processing of a significant amount of spatial data. Geographical information system (GIS) and remote sensing (RS) are valuable tools for assessing health impacts due to landfills. The aims of this study were: (i) to analyze the leachate and gas emissions from landfills used for domestic waste disposal in a metropolitan area of Jiangsu province, China, (ii) to investigate remotely-sensed environmental features in close proximity to landfills, and (iii) to evaluate the compliance of their location and leachate quality with the relevant national regulations. We randomly selected five landfills in the metropolitan areas of Wuxi and Suzhou city, Jiangsu province, established a GIS database and examined whether data were in compliance with national environmental and public health regulations. The leachates of the sampled landfills contained heavy metals (Pb, As, Cr 6+ and Hg) and organic compounds in concentrations considered harmful to human health. Measured methane concentrations on landfill surfaces were low. Spatial analysis of the location of landfills with regard to distance from major water bodies, sensible infrastructure and environmental conditions according to current national legislation resulted in the rejection of four of the five sites as inappropriate for landfills. Our results call for rigorous evaluation of the spatial location of landfills in China that must take into consideration environmental and public health criteria

  8. Hair-brane ideas on the horizon

    Energy Technology Data Exchange (ETDEWEB)

    Martinec, Emil J. [Enrico Fermi Institute and Department of Physics, University of Chicago, 5640 S. Ellis Ave., Chicago, IL 60637-1433 (United States); Niehoff, Ben E. [Department of Applied Mathematics and Theoretical Physics, University of Cambridge,Centre for Mathematical Sciences,Wilberforce Rd., Cambridge, CB3 0WA (United Kingdom)

    2015-11-27

    We continue an examination of the microstate geometries program begun in arXiv:1409.6017, focussing on the role of branes that wrap the cycles which degenerate when a throat in the geometry deepens and a horizon forms. An associated quiver quantum mechanical model of minimally wrapped branes exhibits a non-negligible fraction of the gravitational entropy, which scales correctly as a function of the charges. The results suggest a picture of AdS{sub 3}/CFT{sub 2} duality wherein the long string that accounts for BTZ black hole entropy in the CFT description, can also be seen to inhabit the horizon of BPS black holes on the gravity side.

  9. Dynamical AdS strings across horizons

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Takaaki [University of Colorado,390 UCB, Boulder, CO 80309 (United States); Murata, Keiju [Keio University,4-1-1 Hiyoshi, Yokohama 223-8521 (Japan)

    2016-03-07

    We examine the nonlinear classical dynamics of a fundamental string in anti-de Sitter spacetime. The string is dual to the flux tube between an external quark-antiquark pair in N=4 super Yang-Mills theory. We perturb the string by shaking the endpoints and compute its time evolution numerically. We find that with sufficiently strong perturbations the string continues extending and plunges into the Poincaré horizon. In the evolution, effective horizons are also dynamically created on the string worldsheet. The quark and antiquark are thus causally disconnected, and the string transitions to two straight strings. The forces acting on the endpoints vanish with a power law whose slope depends on the perturbations. The condition for this transition to occur is that energy injection exceeds the static energy between the quark-antiquark pair.

  10. Defense Horizons. Number 79, April 2015

    Science.gov (United States)

    2015-04-01

    control number. 1. REPORT DATE APR 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Defense Horizons. Number...on the block number of the aircraft. While the maritime inverse synthetic aper - ture radar is available on the new RQ-4 Block 40, a more accessible...maintains a loiter time of approximately 24 hours. Its specifications match exactly what would be called for in this type of mission. However, unlike the

  11. Winning Horizon2020 with Open Science

    DEFF Research Database (Denmark)

    Grigorov, Ivo; Elbæk, Mikael Karstensen; Rettberg, Najla

    2016-01-01

    ” in future, rather than just research output. OS can also be an effective tool for research managers to transfer knowledge to society, and optimize the use and re-use by unforeseen collaborators. For funders, OS offers a better return on investment (ROI) for public funding, and underpins the EU Digital...... Agenda by measurably contributing to economic growth. This brief showcases why and how Open Science can optimize your Horizon 2020 proposal evaluation....

  12. Horizons of place in Utzon's Bayview Project

    DEFF Research Database (Denmark)

    Andersen, Michael Asgaard

    In this paper, the horizons of place are discussed in relation to the work of danish architect Jørn Utzon. As one of the most significant personalities of nordic architecture in the second half of the twentieth century, Utzon created a body of work that deals with place in profound and unexpected...... understandings of his work. In doing so, the paper aims at approaching architecture and phenomenology through tensional relationships in the places of Utzon's Bayview project....

  13. VMware Horizon 6 desktop virtualization solutions

    CERN Document Server

    Cartwright, Ryan; Langone, Jason; Leibovici, Andre

    2014-01-01

    If you are a desktop architect, solution provider, end-user consultant, virtualization engineer, or anyone who wants to learn how to plan and design the implementation of a virtual desktop solution based on Horizon 6, then this book is for you. An understanding of VMware vSphere fundamentals coupled with experience in the installation or administration of a VMware environment would be a plus during reading.

  14. New Horizons Pluto Flyby Guest Operations

    Science.gov (United States)

    Simon, M.; Turney, D.; Fisher, S.; Carr, S. S.

    2015-12-01

    On July 14, 2015, after 9.5 years of cruise, NASA's New Horizons spacecraft flew past the Pluto system to gather first images humankind had ever seen on Pluto and its five moons. While much has been discovered about the Pluto system since New Horizons launch in 2006, the system has never been imaged at high resolution and anticipation of the "First Light" of the Pluto system had been anticipated by planetary enthusiasts for decades. The Johns Hopkins Applied Physics Laboratory (APL), which built and operates New Horizons, was the focal point for gathering three distinct groups: science and engineering team members; media and public affairs representatives; and invited public, including VIP's. Guest operations activities were focused on providing information primarily to the invited public and VIP's. High level objectives for the Guest Operations team was set to entertain and inform the general public, offer media reaction shots, and to deconflict activities for the guests from media activities wherever possible. Over 2000 people arrived at APL in the days surrounding closest approach for guest, science or media operations tracks. Reaction and coverage of the Guest Operations events was universally positive and global in impact: iconic pictures of the auditorium waving flags during the moment of closest approach were published in media outlets on every continent. Media relations activities ensured coverage in all key media publications targeted for release, such as the New York Times, Science, Le Monde, and Nature. Social and traditional media coverage of the events spanned the globe. Guest operations activities are designed to ensure that a guest has a memorable experience and leaves with a lifelong memory of the mission and their partnership in the activity. Results, lessons learned, and other data from the New Horizons guest operations activity will be presented and analyzed.

  15. The Horizon Is An Imaginary Line

    DEFF Research Database (Denmark)

    Gill, Bani; Mahendru, Radha

    The Horizon Is An Imaginary Line (THIAI) is a semi-fictional illustrated account of a young Somali woman's encounters as a refugee in India. Through Maryam, we reflect on the lived experiences of alienation and marginalization as an 'outsider' on the fringes of an increasingly bordered world. Des....... Designed partly as an infographic, THIAIL puts into perspective several myths and assumptions about the "refugee crisis" and India's ambiguous role within the global refugee regime....

  16. Isolated and Dynamical Horizons and Their Applications

    Directory of Open Access Journals (Sweden)

    Ashtekar Abhay

    2004-12-01

    Full Text Available Over the past three decades, black holes have played an important role in quantum gravity, mathematical physics, numerical relativity and gravitational wave phenomenology. However, conceptual settings and mathematical models used to discuss them have varied considerably from one area to another. Over the last five years a new, quasi-local framework was introduced to analyze diverse facets of black holes in a unified manner. In this framework, evolving black holes are modelled by dynamical horizons and black holes in equilibrium by isolated horizons. We review basic properties of these horizons and summarize applications to mathematical physics, numerical relativity, and quantum gravity. This paradigm has led to significant generalizations of several results in black hole physics. Specifically, it has introduced a more physical setting for black hole thermodynamics and for black hole entropy calculations in quantum gravity, suggested a phenomenological model for hairy black holes, provided novel techniques to extract physics from numerical simulations, and led to new laws governing the dynamics of black holes in exact general relativity.

  17. A comparative examination of MBR and SBR performance for the treatment of high-strength landfill leachate.

    Science.gov (United States)

    El-Fadel, M; Hashisho, J

    2014-09-01

    The management of landfill leachate is challenging, with relatively limited work targeting high-strength leachate. In this study, the performance of the membrane bioreactor (MBR) and sequencing batch reactor (SBR) technologies are compared in treating high-strength landfill leachate. The MBR exhibited a superior performance with removal efficiencies exceeding 95% for BOD5, TN, and NH3 and an improvement on SBR efficiencies ranging between 21 and 34%. The coupled experimental results contribute in filling a gap toward improving the management of high-strength landfill leachate and providing comparative guidelines or selection criteria and limitations for MBR and SBR applications. Implications: While the sequencing batch reactor (SBR) technology offers some flexibility in terms of cycle time and sequence, its performance is constrained when considering landfill leachate associated with significant variations in quality and quantity. Combining membrane separation and biodegradation processes or the membrane bioreactor (MBR) technology improved removal efficiencies significantly. In the context of leachate management using the MBR technology, more efforts have targeted low-strength leachate with limited attempts at moderate to high strength leachate. In this study, the SBR and MBR technologies were tested under different operating conditions to compare and evaluate their feasibility for the management of high-strength leachate from a full-scale operating landfill. Such a comparison has not been reported for high-strength leachate.

  18. The effect of moisture content on the thermal conductivity of moss and organic soil horizons from black spruce ecosystems in interior alaska

    Science.gov (United States)

    O'Donnell, J. A.; Romanovsky, V.E.; Harden, J.W.; McGuire, A.D.

    2009-01-01

    Organic soil horizons function as important controls on the thermal state of near-surface soil and permafrost in high-latitude ecosystems. The thermal conductivity of organic horizons is typically lower than mineral soils and is closely linked to moisture content, bulk density, and water phase. In this study, we examined the relationship between thermal conductivity and soil moisture for different moss and organic horizon types in black spruce ecosystems of interior Alaska. We sampled organic horizons from feather moss-dominated and Sphagnum-dominated stands and divided horizons into live moss and fibrous and amorphous organic matter. Thermal conductivity measurements were made across a range of moisture contents using the transient line heat source method. Our findings indicate a strong positive and linear relationship between thawed thermal conductivity (Kt) and volumetric water content. We observed similar regression parameters (?? or slope) across moss types and organic horizons types and small differences in ??0 (y intercept) across organic horizon types. Live Sphagnum spp. had a higher range of Kt than did live feather moss because of the field capacity (laboratory based) of live Sphagnum spp. In northern regions, the thermal properties of organic soil horizons play a critical role in mediating the effects of climate warming on permafrost conditions. Findings from this study could improve model parameterization of thermal properties in organic horizons and enhance our understanding of future permafrost and ecosystem dynamics. ?? 2009 by Lippincott Williams & Wilkins, Inc.

  19. Characterization of DOM in landfill leachate polluted groundwater with electrospary LC-MS

    DEFF Research Database (Denmark)

    Persson, L.; Alsberg, T.; Odham, G.

    2001-01-01

    Dissolved organic matter in leachate polluted groundwater, downgradient a landfill, was analysed with electrospray mass spectrometry. The results indicate that the DOM change qualitatively in the gradient, becoming more uniform in functional groups and hydrofobicity. Those changes may affect...

  20. The influence of preliminary aerobic treatment on the efficacy of waste stabilisation under leachate recirculation conditions

    Directory of Open Access Journals (Sweden)

    Monika Suchowska-Kisielewicz

    2014-12-01

    Full Text Available This article presents the changes in the chemical composition of leachate and the concentrations and quantity of methane production in each individual decomposition phases, determined for untreated and after aerobic treatment of waste stabilised in anaerobic reactors with and without leachate recirculation. The research results demonstrate that leachate recirculation intensifies the decomposition of both aerobically treated and untreated waste. The methane production in the reactor with untreated, stabilised waste with recirculation was 28% higher; and in the reactor with aerobically treated waste, the methane production was 24% higher than in the reactors without recirculation. An important finding of the study is that aerobic treatment of waste prior to landfilling effectively reduces the quantity of pollutant emissions in leachate and biogas from waste and increases the availability for methane micro-organisms of organic substrates from difficult-to-decompose organic substances.

  1. Correlation between iron mobilization and emergence of benzene in leachate at old landfills.

    Science.gov (United States)

    Tansel, Berrin

    2013-05-15

    Leachate monitoring data from a closed municipal solid waste (MSW) landfill with negligible gas production showed increasing iron, alkalinity and benzene levels over time. Due to significant rain water infiltration, concentration data alone was not adequate to analyze the possible correlations between the leachate quality parameters monitored. When quantities (kg/d) present in leachate rather than concentrations (mg/L) of benzene, bicarbonate and iron were analyzed; there were significant correlations between benzene and iron as well as biocarbonate and iron quantities. Increasing iron quantity in leachate was accompanied by increasing quantities of benzene and bicarbonate which are indicative of transformation reactions of polymeric organic compounds present in MSW. The results indicate that biotransformation mechanisms in landfills are similar to those in anaerobic sediments due to lack of electron acceptors with higher energy yields. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. LEACHATE MIGRATION FROM A SOLID WASTE DISPOSAL FACILITY NEAR BISCAYNE NATIONAL PARK, SOUTH FLORIDA.

    Science.gov (United States)

    Waller, Bradley G.; Labowski, James L.

    1987-01-01

    Leachate from the Dade County Solid Waste Disposal Facility (SWDF) is migrating to the east (seaward) and to the south from the currently active disposal cell. Water levels and ground-water flow directions are strongly influenced by water-management practices. The SWDF is constructed over the salt-intruded part of the highly transmissive Biscayne aquifer and because of this, chloride ion concentrations and specific conductance levels could not be used as indicators of leachate concentrations. Leachate was detected in multi-depth wells located 75 meters to the south and 20 meters to the east of the active cell. Concentrations of water-quality indicators had mean concentrations generally 2 to 10 times higher than baseline conditions. Primary controls over leachate movement in the SWDF are water-management practices in the Black Creek and Gould Canals, configuration and integrity of the liner beneath the active cell, and low hydraulic gradients in the landfill area.

  3. Fly ash leachate generation and qualitative trends at Ohio test sites

    Energy Technology Data Exchange (ETDEWEB)

    Solc, J.; Foster, H.J.; Butler, R.D. [Energy & Environmental Research Center, Grand Forks, ND (United States)

    1995-12-01

    Under the sponsorship of the U.S. Department of Energy, the environmental impact and potential contamination from landfilled fly ash (coal conversion solid residues - CCSRs) have been studied at field sites in Ohio. The progressive increase of moisture content within pilot cells over depth and time facilitated intensive chemical processes and generation of highly alkaline (pH of 10 to 12) leachate. Chemistry of pore water from lysimeters and ASTM leachate from fly ash and soil cores indicate the leachate potential to migrate out of deposit and impact the pore water quality of surrounding soils. Na, SO{sub 4} and, particularly, K, Cl, pH, and EC appeared to be valuable indicator parameters for tracking potential leachate transport both within the cells and below the ash/soil interface.

  4. Effectiveness of a constructed wetland for treating alkaline bauxite residue leachate: a 1-year field study.

    Science.gov (United States)

    Higgins, Derek; Curtin, Teresa; Courtney, Ronan

    2017-03-01

    Increasing volumes of bauxite residues and their associated leachates represent a significant environmental challenge to the alumina industry. Constructed wetlands have been proposed as a potential approach for leachate treatment, but there is limited data on field-scale applications. The research presented here provides preliminary evaluation of a purpose-built constructed wetland to buffer leachate from a bauxite residue disposal site in Ireland. Data collected over a 1-year period demonstrated that the pH of bauxite residue leachates could be effectively reduced from ca. pH 10.3 to 8.1 but was influenced by influent variability and temporal changes. The wetland was also effective in decreasing elemental loading, and sequential extractions suggested that the bulk of the sediment-bound metal inventory was in hard-to-leach phases. Elemental analysis of Phragmites australis showed that although vegetation displayed seasonal variation, no trace elements were at concentrations of concern.

  5. Lead migration in smelter-impacted deciduous and coniferous organic soil horizons based on a long-term in-situ implantation and laboratory column experiments

    International Nuclear Information System (INIS)

    Chrastný, Vladislav; Vaněk, Aleš; Čadková, Eva; Růžičková, Alice; Galušková, Ivana; Faturíková, Dagmar; Komárek, Michael

    2014-01-01

    Highlights: • Implantation of highly polluted soils to pristine area caused massive Pb migration. • The coniferous forest soil organic horizons were more vulnerable to this effect. • F + H, A and C forest soil horizons efficiently retained Pb added in column experiment. • The L organic forest soil horizon had a very limited sorption ability for Pb. • Under natural conditions, Pb from horizon L could be eluted in less than 5 years. - Abstract: Lead (Pb) contamination of forest soils constitute a serious threat against soil organisms and wildlife and the transport of previously deposited Pb from surface soils is of high environmental relevance. We studied the migration of Pb in highly contaminated deciduous and coniferous soils in a smelting area. A mixture of fermented/humified (F + H) deciduous and coniferous soil horizons highly contaminated by Pb smelting operations were implanted to the same horizon types in an area of low Pb atmospheric input for 6 months. The implantation was accompanied with mechanical turbation, which caused changes in the soil parameters, i.e., CEC (cation exchange capacity), C org. (organic carbon) or pH. The target soil horizons F + H (and partly A) were enriched with Pb, compared to background concentrations. The retention of Pb in smelter-impacted coniferous forest soil horizons L (raw litter), F + H, A (organo-mineral) and C (mineral) was studied using a column experiment. As a result of the Pb addition with a specific isotope composition (American galena) it was found that with the exception of the L horizon, all of the added Pb was completely retained in soil horizons. The isotope composition of Pb in eluate from the L horizon was represented by linear mixing between the original and added Pb sources. The majority of Pb would be eluted from the L horizon after less than 5 years (using linear approximation)

  6. FITOREMEDIASI KADMIUM (CD PADA LEACHATE MENGGUNAKAN KANGKUNG AIR (Ipomoea aquatica Forsk. (STUDI KASUS TPA JATIBARANG

    Directory of Open Access Journals (Sweden)

    K N Zamhar

    2016-03-01

    Full Text Available Leachate TPA Jatibarang yang tercemar kadmium (Cd kemungkinan dapat dibersihkan secara fitoremediasi menggunakan kangkung air (Ipomoea aquatica Forsk.. Penelitian ini bertujuan untuk mengetahui kemampuan kangkung air sebagai fitoremediator dalam menyerap Cd dalam leachate TPA Jatibarang. Sebelum penelitian, dilakukan uji pendahuluan kandungan Cd dalam leachate maupun dalam kangkung air. Kangkung diaklimatisasi dalam air bersih selama 3 hari, selanjutnya ditimbang seberat 300 gram kemudian diletakkan ke dalam ember berisi 10 L leachate. Sampel leachate dan organ tanaman diambil setiap 2 hari sekali (2 hari, 4 hari, 6 hari, dan 8 hari. Faktor intensitas cahaya diambil setiap hari pada pukul 08.00-09.00 WIB menggunakan lux meter, sedangkan nilai pH dan suhu leachate diukur menggunakan kertas indikator pH dan termometer sebelum dan sesudah perlakuan. Perameter yang diamati adalah akumulasi Cd dalam akar, batang, dan daun kangkung air pada masing-masing lama waktu pananaman. Akumulasi Cd diukur dengan AAS (Atomic Absorption Spectrophotometry. Data penyerapan Cd dianalisis secara deskriptif. Hasil penelitian menunjukkan bahwa lama waktu kangkung air ditanam dalam leachate berpengaruh terhadap akumulasi Cd pada tanaman. Penyerapan Cd oleh kangkung air mencapai jenuh pada hari ke-8 dengan total penyerapan 0,052 ppm. Akumulasi Cd paling besar pada akar kangkung yaitu 0,023 ppm.Cadmium (Cd that contained in TPA Jatibarang’s leachate can be cleaned by phytoremediation using water spinach (Ipomoea aquatica Forsk.. This research aimed to determine the ability of the water spinach as a fitoremediator in adsorb cadmium (Cd that contained in TPA Jatibarang’s leachate. The research was conducted by using a randomized completely design (RCD factorial, with longer treatment planted time in leachate water spinach was 0 day, 2 days, 4 days, 6 days, and 8 days respectively. The observed parameters of Cd accumulation in roots, stems, and leaves of water spinach in

  7. Quantification of regional leachate variance from municipal solid waste landfills in China.

    Science.gov (United States)

    Yang, Na; Damgaard, Anders; Kjeldsen, Peter; Shao, Li-Ming; He, Pin-Jing

    2015-12-01

    The quantity of leachate is crucial when assessing pollution emanating from municipal landfills. In most cases, existing leachate quantification measures only take into account one source - precipitation, which resulted in serious underestimation in China due to its waste properties: high moisture contents. To overcome this problem, a new estimation method was established considering two sources: (1) precipitation infiltrated throughout waste layers, which was simulated with the HELP model, (2) water squeezed out of the waste itself, which was theoretically calculated using actual data of Chinese waste. The two sources depended on climate conditions and waste characteristics, respectively, which both varied in different regions. In this study, 31 Chinese cities were investigated and classified into three geographic regions according to landfill leachate generation performance: northwestern China (China-NW) with semi-arid and temperate climate and waste moisture content of about 46.0%, northern China (China-N) with semi-humid and temperate climate and waste moisture content of about 58.2%, and southern China (China-S) with humid and sub-tropical/tropical climate and waste moisture content of about 58.2%. In China-NW, accumulated leachate amounts were very low and mainly the result of waste degradation, implying on-site spraying/irrigation or recirculation may be an economic approach to treatment. In China-N, water squeezed out of waste by compaction totaled 22-45% of overall leachate amounts in the first 40 years, so decreasing the initial moisture content of waste arriving at landfills could reduce leachate generation. In China-S, the leachate generated by infiltrated precipitation after HDPE geomembranes in top cover started failing, contributed more than 60% of the overall amounts over 100 years of landfilling. Therefore, the quality and placing of HDPE geomembranes in the top cover should be controlled strictly for the purpose of mitigation leachate generation

  8. Phycoremediation of landfill leachate with chlorophytes: Phosphate a limiting factor on ammonia nitrogen removal.

    Science.gov (United States)

    Paskuliakova, Andrea; Tonry, Steven; Touzet, Nicolas

    2016-08-01

    The potential of microalgae to bioremediate wastewater has been reported in numerous studies but has not been investigated as extensively for landfill leachate, which may be attributed to its complex nature and toxicity. In this study we explored if microalgal phycoremediation could constitute an alternative biological treatment option for landfill leachate management in regions with temperate climatic conditions. The aim of this study was to assess the performance of microalgae species at relatively low temperature (15 °C) and light intensity (14:10 h, light: dark, 22 μmol m(-2) s(-1)) for reduction in energy inputs. Four chlorophyte strains originating from the North-West of Ireland were selected and used in batch experiments in order to evaluate their ability to reduce total ammonia nitrogen, oxidised nitrogen and orthophosphate in landfill leachate. The Chlamydomonas sp. strain SW15aRL isolated from raw leachate achieved the highest level of pollutant reduction whereby a decrease of 51.7% of ammonia nitrogen was observed in 10% raw leachate (∼100 mg l(-1) NH4(+)-N) by day 24 in experiments without culture agitation. However, in the experiment conducted with 10% raw leachate supplemented with phosphate, a decrease of 90.7% of ammonia nitrogen was obtained by day 24 while also achieving higher biomass production. This series of experiments pointed to phosphorus being a limiting factor in the microalgae based phycoremediation of the landfill leachate. The effective reduction of ammonia nitrogen in landfill leachate can be achieved at lower temperature and light conditions. This was attained by employing native species adapted to such conditions and by improving nutrient balance. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Application of Deuterium and Oxygen-18 to Trace Leachate Movement in Bantar Gebang Sanitary Landfill

    Directory of Open Access Journals (Sweden)

    E.R. Pujiindiyati

    2011-08-01

    Full Text Available Bantar Gebang landfill was constructed in 1986 with total area of 108 ha and approximately 6000 ton/day solid waste is disposed to this landfill. Mostly, the people living surrounding landfill get afraid of impact of the hazardous chemicals produced by waste disposal to their health. The purpose of this investigation was to study the migration of leachate to Cibitung River water and shallow groundwaters near to the river. It is possible to be done because chemical contents and isotopic characteristics of municipal landfill leachate are unique, relative to aqueous media in the most natural environments. Laser absorption method developed by the LGR (Los Gatos Research was used to measure absolute abundances of 2HHO, HH18O and HHO in a number of water samples. In-situ measurements were also conducted as an additional parameter besides their isotopes. The δ2H of the H2O in landfill leachate was significantly enriched, with values of - 22.6 ‰ to + 4.3 ‰. This deuterium enrichment was undoubtedly due to the extensive production of microbial methane within the limited reservoir of the landfill. However, the enriched deuterium value in leachate was not detected in the river which still had depleted values. It was probably caused by the amount of natural water in the river was comparatively large, with respect to limited leachate discarded to the river.The electrical conductivity of the leachate was higher (3200 to 7600 S and the decreasing values were still monitored in the river to approximately 12 km after streaming the landfills. The effect of the high electrical conductivity and enriched deuterium of leachate was not clearly indicated in the groundwater samples which still represented the local precipitation recharge, except a monitoring well located in Bantar Gebang landfill area which has an indication of leachate contamination.

  10. Understanding the causes of toxicity in treated landfill leachate through whole eefluent testing

    OpenAIRE

    Thomas, David J. L

    2010-01-01

    Landfill leachate is collected and treated before discharge to protect the environment from a potential toxic cocktail of substances. In the U.K. biological treatment is the favourite technology for rendering landfill leachate safe due its simple design, effective handling of varying chemical loads and relatively low operating costs. Biological treatment is effective at reducing the concentrations of ammoniacal-nitrogen and the biological oxygen demand (BOD) to acceptable level...

  11. Earthworm additions affect leachate production and nitrogen losses in typical midwestern agroecosystems.

    Science.gov (United States)

    Shuster, William D; Shipitalo, Martin J; Subler, Scott; Aref, Susanne; McCoy, Edward L; McKeegan, Christina

    2003-01-01

    Earthworms affect soil structure and the movement of agrochemicals. Yet, there have been few field-scale studies that quantify the effect of earthworms on dissolved nitrogen fluxes in agroecosystems. We investigated the influence of semi-annual earthworm additions on leachate production and quality in different row crop agroecosystems. Chisel-till corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotation (CT) and ridge-till corn-soybean-wheat (Triticum aestivum L.) rotation (RT) plots were arranged in a complete randomized block design (n = 3) with earthworm treatments (addition and ambient) as subplots where zero-tension lysimeters were placed 45 cm below ground. We assessed earthworm populations semi-annually and collected leachate biweekly over a three-year period and determined leachate volume and concentrations of total inorganic nitrogen (TIN) and dissolved organic nitrogen (DON). Abundance of deep-burrowing earthworms was increased in addition treatments over ambient and for both agroecosystems. Leachate loss was similar among agroecosystems, but earthworm additions increased leachate production in the range of 4.5 to 45.2% above ambient in CT cropping. Although leachate TIN and DON concentrations were generally similar between agroecosystems or earthworm treatments, transport of TIN was significantly increased in addition treatments over ambient in CT cropping due to increased leachate volume. Losses of total nitrogen in leachate loadings were up to approximately 10% of agroecosystem N inputs. The coincidence of (i) soluble N production and availability and (ii) preferential leaching pathways formed by deep-burrowing earthworms thereby increased N losses from the CT agroecosystem at the 45-cm depth. Processing of N compounds and transport in soil water from RT cropping were more affected by management phase and largely independent of earthworm activity.

  12. Characteristics of leachate in Foot and Mouth Disease Carcass Disposal using Molecular Biology Method

    Science.gov (United States)

    Choi, E. J.; Kim, B. J.; Wi, D. W.; Choi, N. C.; Lee, S. J.; Min, J. E.; Park, C. Y.

    2012-04-01

    The Leachate from Foot and Mouth Disease(FMD) carcass disposal by is one of the types of high-concentration contaminated wastewater with the greatest environmental impact. This is due to its pollutants: nitrate nitrogen (NO3--N) and pathogenic microorganisms. Satisfactory treatment of leachate is not an easy task for its high concentrations of nitrate nitrogen and pathogenic microorganisms. Therefore suitable FMD leachate treatment processes should be adopted to improve treatment performance and to reduce overall running costs. The objective of this study was to determine the leachate characteristics through environmental analysis and molecular biology method (bacteria identification and Polymerase Chain Reaction) using FMD leachate samples for optimal FMD leachate treatment processes. The Sixteen FMD leachate samples was obtained from carcass disposal regions in Korea. Results of environmental analysis showed that pH and Eh was observed from 5.57 to 7.40, -134~358mV. This data was exhibited typical early carcass disposal (Neutral pH and Reducing Environment by abundant organic matter). TOC and nitrate nitrogen high concentrations in FMD leachate showed a large variability from 2.3 to 38,730 mg/L(mean - 6,821.93mg/L) and 0.335 ~231.998mg/L(mean - 37.46mg/L), respectively. The result of bacteria identification was observed Bacillus cereus, Pseudomonas putida, Acinetobacter ursingii, Aeromonas hydrophila, Serratia liquefaciens, Brevundimonas naejangsanensis, Serratia liquefaciens, Pseudomonas fluorescens, Pseudomonas aeruginosa, Acinetobacter ursingii. The results of Polymerase Chain Reaction(PCR) using EzTaxon server data revealed Pseudoclavibacter helvolus, Pseudochrobactrum saccharolyticum, Corynebacterium callunae, Paenibacillus lautus, Paenibacillus sp., Bacillus arvi, Brevundimonas bullata, Acinetobacter ursingii, Lysinibacillus sphaericus, Bacillus pumilus, Bacillus sphaericus, Bacillus psychrodurans, Pseudomonas sp.

  13. Biochemical processes in soil and groundwater contaminated by leachates from municipal landfills (Mini review

    Directory of Open Access Journals (Sweden)

    Yu N. Vodyanitskii

    2016-09-01

    Full Text Available World clean water deficit grows by increasing pollution on the planet. Landfill of solid domestic waste is one of the most important sources of pollution, where the leachate seeping through soil, gets into the soil and groundwater. Area of landfills of solid household waste, reaches tens of hectares and the mass of waste reaches millions of tones. The specificity of the leachate is the high content of soluble organic substances, providing reduction conditions in contaminated soil and groundwater. Reduction environment is defines biogeochemical processes under landfills with the participation of: ammonium, iron, manganese, bicarbonate, sulfate, methane. The main processes in polluted soil stream are including: biological degradation of organic matter and a variety of biological and abiotic processes. Wide discrimination of the most diverse groups of microorganisms in the polluted leachate is occurs, overlay neighboring redox zones. Microbial population is identifies specific redox zones more contaminated leachate nucleus than on the borders of the leachate with oxygen-enriched by the background thread. Biological reduction processes in the leachate are developing at different speeds: fast evolving and denitrification reduction of iron, slow – methanogenesis.

  14. Three-dimensional modelling of leachate recirculation using vertical wells in bioreactor landfills.

    Science.gov (United States)

    Feng, Shi-Jin; Chen, Zheng-Wei; Cao, Ben-Yi

    2016-12-01

    Bioreactor landfills use leachate recirculation to enhance the biodegradation of municipal solid waste and accelerate landfill stabilisation, which can provide significant environmental and economic benefits. Vertical wells are operated as a major method for leachate recirculation systems. The objectives of this article are to analyse the leachate migration in bioreactor landfills using vertical wells and to offer theoretical basis for the design of leachate recirculation systems. A three-dimensional numerical model was built using FLAC-3D, and this model can consider the saturated and unsaturated flow of leachate within anisotropic waste to reflect the actual conditions. First, main influence factors of leachate migration were analysed, including the vertical well height, hydraulic conductivity, and anisotropic coefficient, in a single-well recirculation system. Then, the effects of different configurations of a group-well system were studied and the optimal well spacing was obtained. Some key design parameters (e.g. the recirculation flow rate, volume of impact zone, radius of impact zone and time to reach steady state) were also evaluated. The results show that the hydraulic conductivity has a great impact on the optimal height of vertical wells and uniform configuration is the best option in terms of both volume of impact zone and time to reach steady state. © The Author(s) 2016.

  15. Membrane bioreactor technology: A novel approach to the treatment of compost leachate

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Kayleigh; Ghoshdastidar, Avik J.; Hanmore, Jillian [Department of Chemistry, Acadia University, Wolfville, NS, Canada B4P 2R6 (Canada); Frazee, James [E and Q Consulting and Associates Limited, Wolfville, NS, Canada B4P 2R1 (Canada); Tong, Anthony Z., E-mail: anthony.tong@acadiau.ca [Department of Chemistry, Acadia University, Wolfville, NS, Canada B4P 2R6 (Canada)

    2013-11-15

    Highlights: • First membrane bioreactor treatment method for compost leachate. • No chemical additive or UV radiation source in this new biological method. • Removal rates of more than 99% for organics and ammonium were achieved. • Heavy metals were reduced by at least 82.7% except copper. - Abstract: Compost leachate forms during the composting process of organic material. It is rich in oxidizable organics, ammonia and metals, which pose a risk to the environment if released without proper treatment. An innovative method based on the membrane bioreactor (MBR) technology was developed to treat compost leachate over 39 days. Water quality parameters, such as pH, dissolved oxygen, ammonia, nitrate, nitrite and chemical oxygen demand (COD) were measured daily. Concentrations of caffeine and metals were measured over the course of the experiment using gas chromatography – mass spectrometry (GC/MS) and inductively coupled plasma – mass spectrometry (ICP–MS) respectively. A decrease of more than 99% was achieved for a COD of 116 g/L in the initial leachate. Ammonia was decreased from 2720 mg/L to 0.046 mg/L, while the nitrate concentration in the effluent rose to 710 mg/L. The bacteria in the MBR system adjusted to the presence of the leachate, and increased 4 orders of magnitude. Heavy metals were removed by at least 82.7% except copper. These successful results demonstrated the membrane bioreactor technology is feasible, efficient method for the treatment of compost leachate.

  16. An Interactive Real-time Decision Support System for Leachate Irrigation on Evapotranspiration Landfill Covers

    Science.gov (United States)

    Wang, Y.

    2015-12-01

    Landfill disposal is still the most common and economical practice for municipal solid waste in most countries. However, heavily polluted leachate generated by excess rainwater percolating through the landfill waste is the major drawback of this practice. Evapotranspiration (ET) cover systems are increasingly being used as alternative cover systems to minimize percolation by evapotranspiration. Leachate recirculation is one of the least expensive options for leachate treatment. The combination of ET cover systems and leachate recirculation can be an economical and environment-friendly practice for landfill leachate management. An interactive real-time decision support system is being developed to better manage leachate irrigation using historical and forecasting weather data, and real time soil moisture data. The main frame of this system includes soil water modules, and plant-soil modules. An inverse simulation module is also included to calibrate certain parameters based on observed data when necessary. It would be an objectives-oriented irrigation management tool to minimize landfill operation costs and negative environmental impacts.

  17. Leachate Characterization from a Closed Landfill in Air Hitam, Puchong, Malaysia

    International Nuclear Information System (INIS)

    Nur Fatin Dahlia Mat Salleh; Ku Halim Ku Hamid

    2013-01-01

    Leachate, wastewater that was collected from landfill is known to have pungent smell and may impose serious harm to human health and the environment. Air Hitam, Puchong Sanitary Landfill has stopped its land filling operation since December 2006 and is under post-closure maintenance stages. After several years of stopping its operation, a landfill will still produce leachate hence it needs constant monitoring and maintenance. The main aim of this paper was to characterize leachate produced from Air Hitam, Puchong Closed Landfill, according to several important parameters: pH, temperature, chemical oxygen demand (COD), ammoniacal nitrogen (NH 4 -N), total organic carbon (TOC), total solids, volatile organic acids (VOA) and heavy metals content, to determine its suitability in producing methane by identifying its phase. Leachate samples were drawn weekly for a period of 3 months from three different ponds, untreated raw leachate pond 1 and treated leachate pond 2 and 3. Results obtained showed that the average values were around 25 degree Celsius, average pH 8, highest COD reading was 5,248 mg/L, TOC highest at 6,797 mg/L, VOA highest at 1,424 mg/L and ammoniacal content of 3.10 mg/L the highest. (author)

  18. Treatment of landfill leachate using ASBR combined with zeolite adsorption technology.

    Science.gov (United States)

    Lim, Chi Kim; Seow, Ta Wee; Neoh, Chin Hong; Md Nor, Muhamad Hanif; Ibrahim, Zaharah; Ware, Ismail; Mat Sarip, Siti Hajar

    2016-12-01

    Sanitary landfilling is the most common way to dispose solid urban waste; however, improper landfill management may pose serious environmental threats through discharge of high strength polluted wastewater also known as leachate. The treatment of landfill leachate to fully reduce the negative impact on the environment, is nowadays a challenge. In this study, an aerobic sequencing batch reactor (ASBR) was proposed for the treatment of locally obtained real landfill leachate with initial ammoniacal nitrogen and chemical oxygen demand (COD) concentration of 1800 and 3200 mg/L, respectively. ASBR could remove 65 % of ammoniacal nitrogen and 30 % of COD during seven days of treatment time. Thereafter, an effective adsorbent, i.e., zeolite was used as a secondary treatment step for polishing the ammoniacal nitrogen and COD content that is present in leachate. The results obtained are promising where the adsorption of leachate by zeolite further enhanced the removal of ammoniacal nitrogen and COD up to 96 and 43 %, respectively. Furthermore, this combined biological-physical treatment system was able to remove heavy metals, i.e. aluminium, vanadium, chromium, magnesium, cuprum and plumbum significantly. These results demonstrate that combined ASBR and zeolite adsorption is a feasible technique for the treatment of landfill leachate, even considering this effluent's high resistance to treatment.

  19. Leachate migration from a solid waste disposal facility near Biscayne National Park, South Florida

    International Nuclear Information System (INIS)

    Waller, B.G.; Labowski, J.L.

    1987-01-01

    Leachate from the Dade County Solid Waste Disposal Facility (SWDF) is migrating to the east (seaward) and to the south from the currently active disposal cell. Water levels and ground-water flow directions are strongly influenced by water-management practices, especially in the Black Creek Canal and structure S-21 to the north of the SWDF. Ground-water flow is initially to the south, from Black Creek Canal, and then to the east through the disposal area. The SWDF is constructed over the salt-intruded part of the highly transmissive Biscayne aquifer and because of this, chloride ion concentrations and specific conductance levels could not be used as indicators of leachate concentrations. Water-quality indicators used to identify leachate migration were primarily ammonium, organic nitrogen, phenols, and chemical oxygen demand with cadmium, chromium, and lead used as auxiliary indicator constituents. Leachate was detected in multi-depth wells located 75 meters to the south and 20 meters to the east of the active cell. Concentrations of water-quality indicators had mean concentrations generally 2 to 10 times higher than baseline conditions. Leachate was not detected in any of the other ground-water, canal water, or Biscayne Bay sampling sites. Primary controls over leachate movement in the SWDF are water-management practices in the Black Creek and Gould Canals, configuration and integrity of the liner beneath the active cell, and low hydraulic gradients in the landfill area

  20. A coupled system of half-nitritation and ANAMMOX for mature landfill leachate nitrogen removal.

    Science.gov (United States)

    Li, Yun; Li, Jun; Zhao, Baihang; Wang, Xiujie; Zhang, Yanzhuo; Wei, Jia; Bian, Wei

    2017-09-01

    A coupled system of membrane bioreactor-nitritation (MBR-nitritation) and up-flow anaerobic sludge blanket-anaerobic ammonium oxidation (UASB-ANAMMOX) was employed to treat mature landfill leachate containing high ammonia nitrogen and low C/N. MBR-nitritation was successfully realized for undiluted mature landfill leachate with initial concentrations of 900-1500 mg/L [Formula: see text] and 2000-4000 mg/L chemical oxygen demand. The effluent [Formula: see text] concentration and the [Formula: see text] accumulation efficiency were 889 mg/L and 97% at 125 d, respectively. Half-nitritation was quickly realized by adjustment of hydraulic retention time and dissolved oxygen (DO), and a low DO control strategy could allow long-term stable operation. The UASB-ANAMMOX system showed high effective nitrogen removal at a low concentration of mature landfill leachate. The nitrogen removal efficiency was inhibited at excessive influent substrate concentration and the nitrogen removal efficiency of the system decreased as the concentration of mature landfill leachate increased. The MBR-nitritation and UASB-ANAMMOX processes were coupled for mature landfill leachate treatment and together resulted in high effective nitrogen removal. The effluent average total nitrogen concentration and removal efficiency values were 176 mg/L and 83%, respectively. However, the average nitrogen removal load decreased from 2.16 to 0.77 g/(L d) at higher concentrations of mature landfill leachate.

  1. The potential for constructed wetlands to treat alkaline bauxite-residue leachate: Phragmites australis growth.

    Science.gov (United States)

    Higgins, D; Curtin, T; Pawlett, M; Courtney, R

    2016-12-01

    High alkalinity (pH > 12) of bauxite-residue leachates presents challenges for the long-term storage and managements of the residue. Recent evidence has highlighted the potential for constructed wetlands to effectively buffer the alkalinity, but there is limited evidence on the potential for wetland plants to establish and grow in soils inundated with residue leachate. A pot-based trial was conducted to investigate the potential for Phragmites australis to establish and grow in substrate treated with residue leachate over a pH range of 8.6-11.1. The trial ran for 3 months, after which plant growth and biomass were determined. Concentrations of soluble and exchangeable trace elements in the soil substrate and also in the aboveground and belowground biomass were determined. Residue leachate pH did not affect plant biomass or microbial biomass. With the exception of Na, there was no effect on exchangeable trace elements in the substrate; however, increases in soluble metals (As, Cd and Na) were observed with increasing leachate concentration. Furthermore, increases in Al, As and V were observed in belowground biomass and for Cd and Cr in aboveground biomass. Concentrations within the vegetation biomass were less than critical phytotoxic levels. Results demonstrate the ability for P. australis to grow in bauxite-residue leachate-inundated growth media without adverse effects.

  2. Environmental risk index: A tool to assess the safety of dams for leachate

    International Nuclear Information System (INIS)

    Colomer Mendoza, Francisco J.; Gallardo Izquierdo, Antonio

    2009-01-01

    Dams for leachate store very toxic substances that contain a large amount of organic material and, probably, heavy metals; they therefore constitute an important threat to the environment. Existing models of environmental risk assessment for landfills do not take into consideration the specific risk that leachate dams may represent for the environment. In this paper a methodology to improve the environmental safety is presented according to the parameters used in their construction and management. In order to do that, the following characteristics of the dam must be known: (1) geotechnical stability, (2) erosion of downstream slope, (3) type of sealing of the dam, (4) overtopping probability, (5) volume of leachate stored inside the dam and (6) pollution load of leachate. Once these parameters have been calculated, they are transformed by means of rating curves into homogeneous units, so as to make it possible to operate between them. From the study and analysis of these parameters an environmental risk index for a dam for leachate can be calculated. If the environmental risk index exceeds an established value then it involves a dam for leachate with high environmental risk, therefore preventive measures in its design, construction and management would be necessary

  3. Acute toxicity test of leachates from traditional and sustainable landfills using luminescent bacteria

    International Nuclear Information System (INIS)

    Pivato, Alberto; Gaspari, Lorenzo

    2006-01-01

    Landfilling is a fundamental step in any waste management strategy, but it can constitute a hazard for the environment for a long time. The need to protect the environment from potential landfill emissions makes risk assessment a decision tool of extreme necessity. The heterogeneity of wastes and the complexity of physical, chemical and biological processes that occur in the body of a landfill need specific procedures in order to evaluate the groundwater risk for the environment. Given the complexity of the composition of landfill leachates, the exact contribution of each potential toxic substance cannot be known precisely. Some reference contaminants that constitute the hazard (toxicity) of leachate have to be found to perform the risk assessment. A preliminary ecotoxicological investigation with luminescent bacteria has been carried out on different leachates from traditional and sustainable landfills in order to rank the chemicals that better characterize the leachate (heavy metals, ammonia and dissolved organic content). The attention has been focused on ammonia because it is present in high concentration and can last for centuries and can seriously contaminate the groundwater. The results showed that the toxicity of the leachate might reliably depend on the ammonia concentration and that the leachate toxicity is considerably lower in sustainable landfills where the ammonia had been degraded. This has an important consequence because if the containment system fails (as usually occur within 30-50 yr), the risk of groundwater contamination will be calculated easier only in terms of the probability that the ammonia concentration is higher than a reference concentration

  4. Landfill wall revegetation combined with leachate recirculation: a convenient procedure for management of closed landfills.

    Science.gov (United States)

    Del Moro, G; Barca, E; Cassano, D; Di Iaconi, C; Mascolo, G; Brunetti, G

    2014-01-01

    There is a need for a reliable sustainable option to effectively manage the landfill leachate generation. This study presents a simple procedure for the revegetation of the walls of closed landfills, employing the leachate as a fertirrigant. The native plants Lepidium sativum, Lactuca sativa, and Atriplex halimus, which suit the local climate, were chosen for this study in Southern Italy. The methodology was structured into three phases (i) early stage toxicity assessment phase (apical root length and germination tests), (ii) adult plant resistance assessment phase, and (iii) soil properties verification phase. The rationale of the proposed approach was first to look at the distinctive qualities and the potential toxicity in landfill leachates for fertigation purposes. Afterwards, through specific tests, the plants used were ranked in terms of resistance to the aqueous solution that contained leachate. Finally, after long-term irrigation, any possible worsening of soil properties was evaluated. The results demonstrated the real possibility of using blended leachate as a fertigant for the revegetation of the walls of closed landfills. In particular, the plants maintained good health when leachate was blended at concentrations of lower than 25 and 5%, respectively for A. halimus and Lepidium sativum. Irrigation tests showed good resistance of the plants, even at dosages of 112 and 133.5 mm m(-2), at maximum concentrations of 25 and 5%, respectively, for A. halimus and Lepidium sativum. The analysis of the total chlorophyll content and of aerial parts dried weight confirmed the results reported above.

  5. Determination of leachate toxicity through acute toxicity using Daphnia pulex and anaerobic toxicity assays

    Directory of Open Access Journals (Sweden)

    Patricia Torres Lozada

    2017-01-01

    Full Text Available The municipal solid waste (MSW of large cities, in particular in developing countries, is mainly disposed of in landfills (LFs, whose inadequate management generates the emission of greenhouse gases and the production of leachates with high concentrations of organic and inorganic matter and occasionally heavy metals. In this study, the toxicity of the leachates from an intermediate-age municipal landfill was evaluated by ecotoxicity and anaerobic digestion tests. The acute toxicity assays with Daphnia pulex presented a toxic unit (TU value of 49.5%, which indicates that these leachates should not be directly discharged into water sources or percolate into the soil because they would affect the ecosystems served by these waters. According to statistical analyses, the leachate toxicity is mainly associated with the inorganic fraction, with chlorides, calcium hardness and calcium having the greatest influence on the toxicity. The anaerobic toxicity assays showed that in the exposure stage, the methanogenic activity exceeded that of the control, which suggests that the anaerobic bacteria easily adapted to the leachate. Therefore, this treatment could be an alternative to mitigate the toxicity of the studied leachates. The inhibition presented in the recovery stage, represented by a reduction of the methanogenic activity, could arise because the amount of supplied substrate was not enough to fulfill the carbon and nutrient requirements of the bacterial population present.

  6. MINERAL HORIZONS, ELECTROMAGNETIC FIELDS AND CIRCULAR SHAPES IN THE GRASS

    Directory of Open Access Journals (Sweden)

    Valentino Straser

    2009-12-01

    Full Text Available The occasional appearance of circular shapes in meadows and farmland located on slopes usually affected by gravitational phenomena, offered an occasion for verifying the possible relation between the position of the circles in the grass, the gravitational movement of the slope affecting its mineral horizons and the variations of electric and static magnetic fields close to the circular shapes and in the surrounding area. The stress caused by the “creeping” movement in the uderlying ground turned out to be in direct relation with the variation in the electric and magnetic fields caused by piezoelectric and piezomagnetic minerals such as quartz. The onset of the electromagnetic process involves the conversion of electric energy on the surface into an area of spherical shape which is linked with a different growth of herbaceous species compared to the surrounding vegetation.

  7. Landfill leachate treatment by coagulation/flocculation combined with microelectrolysis-Fenton processes.

    Science.gov (United States)

    Luo, Kun; Pang, Ya; Li, Xue; Chen, Fei; Liao, Xingsheng; Lei, Min; Song, Yong

    2018-02-07

    Landfill leachate was pretreated by chemical flocculation with polyaluminum chloride (PAC) as a flocculant, and subsequently purified by the microelectrolysis-Fenton (MEF) process. Response surface methodology was employed to optimize the MEF process, and the optimal conditions were initial pH 3.20, H 2 O 2 concentration 3.57 g/L, and Fe-C dosage 104.52 g/L. The PAC coagulation combined with MEF processes obtained a superior decontamination performance, and the predicted chemical oxygen demand (COD) and humic acids (HA) removal were respectively 90.27% and 93.79%. The strong fluorescence peak at 425 nm and the trapping experiment showed that [Formula: see text] was generated during MEF, which had a strong oxidation ability to degrade organic recalcitrant pollutants. The ultraviolet-visible spectra and three-dimensional excitation-emission matrices spectra (3D-EEMs) indicated that PAC coagulation could preferentially remove protein-like substances, while the MEF process was effective in destructing organic recalcitrant pollutants, especially humic-like and fulvic-like substances.

  8. Ecotoxicological Risk Assessment Of Heavy Metals From Leachate Of The Wild Landfill Of El Hajeb City Morocco

    OpenAIRE

    Abderrahmane Gamar; Zakaria Khiya; Touria Zair; Mohammed El Kabriti; Abdelaziz Bouhlal; Fatima El Hilali

    2017-01-01

    The presence of heavy metals in landfill leachates poses a risk to the environment especially in the unpaved dumps where their dissipation in groundwater might occur. This study is focused on the assessment of heavy metal load in landfill leachate of El Hajeb Morocco and their effects on the environment in general. To do this raw leachate samples were collected monthly from basins available at the heart of the landfill and analyzed using the atomic absorption spectrophotometer AAS to quantify...

  9. Leachate From Expanded Polystyrene Cups Is Toxic to Aquatic Invertebrates (Ceriodaphnia dubia

    Directory of Open Access Journals (Sweden)

    Clara Thaysen

    2018-02-01

    Full Text Available Expanded polystyrene (EPS products and their associated chemicals (e.g., styrenes are widespread in the marine environment. As a consequence, bans on their use for single-use packaging materials are being proposed in several municipalities. To better understand how science can inform decision-making, we looked at the available scientific literature about contamination and effects and conducted experiments to measure chemical leachate from polystyrene products and toxicity from the leachate. We conducted leaching experiments with common food matrices (water, soup broth, gravy, black coffee and coffee with cream and sugar at relevant temperatures (70 and 95°C that are consumed in or with several polystyrene products (coffee cup lids, polystyrene stir sticks, polystyrene spoons, EPS cups, EPS bowls, and EPS takeout containers. We analyzed each sample for styrene, ethylbenzene, toluene, benzene, meta- and para- xylene, isopropylbenzene, and isopropyltoluene—chemicals associated with polystyrene products. To determine whether the leachates are toxic, we conducted chronic toxicity tests, measuring survival and reproductive output in Ceriodaphnia dubia. Toxicity tests included nine treatments: seven concentrations of ethylbenzene, EPS cup leachate and a negative control. Overall, we found that temperature has a significant effect on leaching. We only detected leachates in trials conducted at higher temperature −95°C. Ethylbenzene was the only target analyte with final concentrations above the method limit of detection, and was present in the greatest concentrations in EPS and with soup broth. Measurable concentrations of ethylbenzene in the leachate ranged from 1.3 to 3.4 μg/L. In toxicity tests, the calculated LC50 for ethylbenzene was 14 mg/L and the calculated LC20 was 210 μg/L. For the treatment exposed to the EPS cup leachate, mortality was 40%—four times greater than the negative control. Finally, there was no significant difference (p

  10. Design of a reverse osmosis plant for leachate treatment aiming for safe disposal.

    Science.gov (United States)

    Thörneby, Lars; Hogland, William; Stenis, Jan; Mathiasson, Lennart; Somogyi, Pernilla

    2003-10-01

    Leachate treatment is one of the major environmental issues faced by landfill owners. One promising method for reduction of pollutant discharge is reverse osmosis (RO). RO technology was tested at a pilot plant at Hedeskoga Landfill in southern Sweden. This landfill receives municipal solid waste (MSW) and industrial, commercial and institutional (IC&I) waste, and produces about 3000 m3/ha of leachate annually. Annual variations in the volume of leachate produced, estimated from changes in leachate electrical conductivity, were relatively small and should therefore have a minor effect on the main performance parameter of an RO plant, i.e., the achievable volume reduction. The volume reduction (V(permeate)/V(feed)) of polluted water achieved in batch experiments with 200-1000 litres of raw leachate was more than 80% (4MPa) and the remaining 20% was left as retentate. However, raw leachate caused severe fouling problems in a continuous flow run and after 24 hours, the flux had decreased to about 20% of the initial value. By pre-treating the leachate in a storage pond combined with a wetland, the situation was significantly improved and the decrease in membrane flux was only 0.2% per hour during a 200 hour run. The retention in terms of total solids and chemical oxygen demand was 90%, and for ammonia, it was 82%, at a volume reduction of 50%. The HELP-model was used for prediction of the water balance for the Hedeskoga landfill, with special focus on estimation of potential evapotranspiration. With different types of vegetation and a volume reduction of 75% in the RO plant, it was found possible to achieve safe disposal by irrigating 25% to 40% of the leachate-producing landfill area with pre-treated leachate. Pre-treatment with wetlands and nature based systems reduce the need of detergents for cleaning of the membranes and water only can be used. Short pre-treatment by aeration is not sufficient to bring leachate to a condition sustainable for RO-treatment. In that

  11. Three horizons: a pathways practice for transformation

    Directory of Open Access Journals (Sweden)

    Bill Sharpe

    2016-06-01

    Full Text Available Global environmental change requires responses that involve marked or qualitative changes in individuals, institutions, societies, and cultures. Yet, while there has been considerable effort to develop theory about such processes, there has been limited research on practices for facilitating transformative change. We present a novel pathways approach called Three Horizons that helps participants work with complex and intractable problems and uncertain futures. The approach is important for helping groups work with uncertainty while also generating agency in ways not always addressed by existing futures approaches. We explain how the approach uses a simple framework for structured and guided dialogue around different patterns of change by using examples. We then discuss some of the key characteristics of the practice that facilitators and participants have found to be useful. This includes (1 providing a simple structure for working with complexity, (2 helping develop future consciousness (an awareness of the future potential in the present moment, (3 helping distinguish between incremental and transformative change, (4 making explicit the processes of power and patterns of renewal, (5 enabling the exploration of how to manage transitions, and (6 providing a framework for dialogue among actors with different mindsets. The complementarity of Three Horizons to other approaches (e.g., scenario planning, dilemma thinking is then discussed. Overall, we highlight that there is a need for much greater attention to researching practices of transformation in ways that bridge different kinds of knowledge, including episteme and phronesis. Achieving this will itself require changes to contemporary systems of knowledge production. The practice of Three Horizons could be a useful way to explore how such transformations in knowledge production and use could be achieved.

  12. An uneventful horizon in two dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Almheiri, Ahmed; Sully, James [Department of Physics, University of California,Santa Barbara, CA 93106 (United States)

    2014-02-25

    We investigate the possibility of firewalls in the Einstein-dilaton gravity model of CGHS. We use the results of the numerical simulation carried out by Ashtekar et al. to demonstrate that firewalls are absent and the horizon is drama free. We show that the lack of a firewall is consistent because the model does not satisfy one of the postulates of black hole complementarity. In particular, we elaborate on previous work showing that the Hawking radiation is not pure, and is completely entangled with a long-lived remnant beyond the last ray.

  13. Black hole thermodynamics from Euclidean horizon constraints.

    Science.gov (United States)

    Carlip, S

    2007-07-13

    To explain black hole thermodynamics in quantum gravity, one must introduce constraints to ensure that a black hole is actually present. I show that for a large class of black holes, such "horizon constraints" allow the use of conformal field theory techniques to compute the density of states, reproducing the Bekenstein-Hawking entropy in a nearly model-independent manner. One standard string theory approach to black hole entropy arises as a special case, lending support to the claim that the mechanism may be "universal." I argue that the relevant degrees of freedom are Goldstone-boson-like excitations arising from the weak breaking of symmetry by the constraints.

  14. Art, the Urban Skyscraper, and Horizon Astronomy

    Science.gov (United States)

    Mooney, J. D.

    2016-01-01

    This presentation delineates the historiography and the iconography of my urban public sculptures which use skyscrapers as today's standing stones, markers for horizon astronomy. From 1977 to the present time, my work has engaged the public to “look up and see.” Through ephemeral works in the sky and over the water to large-scale rooftop sculptures in Los Angeles, Chicago, Atlanta, and Europe, viewers are oriented to the Milky Way, the summer triangle, and other celestial phenomena. This new urban scale art, transformative in context and gesture, has become part of the new cultural landscape.

  15. 'Lignes de fuite vers L'Horizon'

    OpenAIRE

    Devine, Jenny

    2011-01-01

    With the publication of L’Horizon in 2010, Patrick Modiano introduces a new perspective in his writings. The title alone indicates a fresh direction, a projection into a realm of possibility and potential, marking a significant departure from the apparent retrospection of his preceding texts (Dans le café de la jeunesse perdue, Du plus loin de l’oubli, Vestiaire de l’enfance….). Informed and enlightened by Nietzschean philosophy, this thesis traces a narrative of liberation in Modiano’s writ...

  16. Quantum chaos and the black hole horizon

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    Thanks to AdS/CFT, the analogy between black holes and thermal systems has become a practical tool, shedding light on thermalization, transport, and entanglement dynamics. Continuing in this vein, recent work has shown how chaos in the boundary CFT can be analyzed in terms of high energy scattering right on the horizon of the dual black hole. The analysis revolves around certain out-of-time-order correlation functions, which are simple diagnostics of the butterfly effect. We will review this work, along with a general bound on these functions that implies black holes are the most chaotic systems in quantum mechanics. (NB Room Change to Main Auditorium)

  17. Aligning European OA policies with Horizon 2020

    OpenAIRE

    Picarra, Mafalda; Angelaki, Marina; Dogan, Guleda; Guy, Marieke; Artusio, Claudio

    2015-01-01

    This article considers that the Horizon 2020 (H2020) Open Access (OA) policy can be adopted as a policy model in European Research Area (ERA) countries for the development and increasing alignment of OA policies. Accordingly, the OA policy landscape in five ERA countries – Greece, Italy, the Netherlands, Turkey and the UK – is assessed and the extent of alignment or divergence of those policies with the H2020 OA policy is examined. The article concludes by considering some of the impacts that...

  18. Effect of Domestic Waste Leachates on Quality Parameters of Groundwater

    Directory of Open Access Journals (Sweden)

    John Jiya MUSA

    2014-02-01

    Full Text Available Water is an elixir of life. Percolating groundwater provides a medium through which wastes particularly organics can undergo degradation into simpler substances through biochemical reactions involving dissolution, hydrolysis, oxidation and reduction processes. Ground water samples in and around dumpsite and landfills located in Kubuwa were studied to assess the effect of wastewater leachates on groundwater resources in the particular area. Groundwater samples were collected from 5 different bore-wells in and around relative distances from dumpsites. EC values ranged between 30 and 138 µS/cm, TDS ranged between 95 mg/L and 120 mg/L, SS ranged between 10 and 23 mg/L while that of the evening ranged between 11 and 15 mg/L, nitrate values ranged between 0.18 to 0.80 mg/L for the early morning samples while the late evening samples which ranged between 0.25 and 0.43 mg/L, while concentration of Sulphate in the morning water sample ranged between 168 and 213 mg/L while that of the evening ranged between 20 and 45 mg/L. The government of the Federal Republic of Nigeria should create landfills and dumpsites far away from residential homes and better still recycling plants should be put in place to recycle the various forms of waste products from homes.

  19. Ammonia recovery from landfill leachate using hydrophobic membrane contactors.

    Science.gov (United States)

    Amaral, Míriam C S; Magalhães, Nátalie C; Moravia, Wagner G; Ferreira, Carolina D

    2016-11-01

    This article aims to evaluate membrane contactors capability to remove and recover ammonia from landfill leachate (LFL). A hydrophobic hollow fiber membrane module was used to achieve such purpose. A sulfuric acid diluted solution was used as extraction solution to speed up ammonia content removal. Several factors that have influence on ammonia removal and recovery capability such as ammonia solution pH, concentration of sulfuric acid solutions and flow rate of liquid phases have been examined. Microfiltration was the method used as pretreatment. The results have shown that membrane contactor operated with LFL (pH 10), 0.1 M acid solution and liquid flow rate up to 0.5 L min -1 achieved 99.9% of ammonia removal, which corresponds to 79.1% of ammonia recovery from the extraction solution, and it is capable to produce highly purified ammonium sulfate solutions (41.2%, wt wt -1 ) to be used as fertilizer. The concentration of total ammonia nitrogen (TAN) in the residual LFL complies with Brazilian law requirements of 20.0 mg L -1 of TAN, regarding the disposal of effluents.

  20. The organic geochemistry of a sanitary landfill leachate plume

    Science.gov (United States)

    Barker, J. F.; Tessmann, J. S.; Plotz, P. E.; Reinhard, M.

    1986-02-01

    Leachate from the North Bay municipal landfill has contaminated an unconfined, sandy aquifer throughout the 700 m flow system from the site to a discharge zone at a creek. The major organic contaminants identified are aromatic hydrocarbons, especially substituted benzenes. The high groundwater velocity of about 75 m yr -1 and the low organic sorption properties of the sand have permitted non-transformed contaminants to spread throughout the total flow system. There is considerable temporal and spatial variability in groundwater chemistry. Most of the aqueous organic carbon has a nominal molecular weight of anarobic segment of the flow system 1,2,4-trimethylbenzene and 1,4-dichlorobenzene are equally persistent, but in the final, less anaerobic segment, the former appears to be degraded more rapidly than the latter. Contaminant distributions in aquifers reflect the results of a number of processes integrated in a complex manner and so are difficult to interpret in terms of specific processes. However, they do provide evidence for what processes are most significant in real groundwater systems and they will also provide critical tests of how well laboratory-derived information relates to real groundwater contamination situations.

  1. Some Limits of Biocompatibility Testing for Lipophilic Leachates

    Directory of Open Access Journals (Sweden)

    Anne D. Lucas

    2012-06-01

    Full Text Available Medical device standards recommend using both a polar and non-polar solvent to extract materials prior to in vitro testing. Testing lipophilic extract in cell culture systems is limited by the toxicity of the lipophilic solvents used in extraction. Use of agar overlay and direct contact methods do not directly address the problem of testing for highly lipophilic leachates from device or material extracts. This particular problem was approached by 1 use of hydrotropes, and 2 by sealing the suspended cells in dialysis tubing and placing it directly in oil or media. The use of hydrotropes to eliminate micelle formation and increase the solubility of lipophilic compounds was not useful as the hydrotropes themselves were toxic to the cells at concentrations that significantly increased analyte solubility. Diffusion of hydrophobic compounds from either peanut oil or cell culture media into the dialysis tubing where the test cells in media reside was significantly higher for the cell culture media than the peanut oil. There were significant differences in toxicity for cells in dialysis tubing from devices extracted between peanut oil and media. This study illustrates the importance of examining if cell toxicity due to micelle formation versus that of soluble chemicals for lipophilic extracts.

  2. Some Limits of Biocompatibility Testing for Lipophilic Leachates

    Directory of Open Access Journals (Sweden)

    Anne Lucas

    2012-05-01

    Full Text Available Medical device standards recommend using both a polar and non-polar solvent to extract materials prior to in vitro testing.  Testing lipophilic extract in cell culture systems is limited by the toxicity of the lipophilic solvents used in extraction. Use of agar overlay and direct contact methods do not directly address the problem of testing for highly lipophilic leachates from device or material extracts. This particular problem was approached by 1 use of hydrotropes, and 2 by sealing the suspended cells in dialysis tubing and placing it directly in oil or media. The use of hydrotropes to eliminate micelle formation and increase the solubility of lipophilic compounds was not useful as the hydrotropes themselves were toxic to the cells at concentrations that significantly increased analyte solubility. Diffusion of hydrophobic compounds from either peanut oil or cell culture media into the dialysis tubing where the test cells in media reside was significantly higher for the cell culture media than the peanut oil. There were significant differences in toxicity for cells in dialysis tubing from devices extracted between peanut oil and media. This study illustrates the importance of examining if cell toxicity due to micelle formation versus that of soluble chemicals for lipophilic extracts.

  3. Optimized evaporation technique for leachate treatment: Small scale implementation.

    Science.gov (United States)

    Benyoucef, Fatima; Makan, Abdelhadi; El Ghmari, Abderrahman; Ouatmane, Aziz

    2016-04-01

    This paper introduces an optimized evaporation technique for leachate treatment. For this purpose and in order to study the feasibility and measure the effectiveness of the forced evaporation, three cuboidal steel tubs were designed and implemented. The first control-tub was installed at the ground level to monitor natural evaporation. Similarly, the second and the third tub, models under investigation, were installed respectively at the ground level (equipped-tub 1) and out of the ground level (equipped-tub 2), and provided with special equipment to accelerate the evaporation process. The obtained results showed that the evaporation rate at the equipped-tubs was much accelerated with respect to the control-tub. It was accelerated five times in the winter period, where the evaporation rate was increased from a value of 0.37 mm/day to reach a value of 1.50 mm/day. In the summer period, the evaporation rate was accelerated more than three times and it increased from a value of 3.06 mm/day to reach a value of 10.25 mm/day. Overall, the optimized evaporation technique can be applied effectively either under electric or solar energy supply, and will accelerate the evaporation rate from three to five times whatever the season temperature. Copyright © 2016. Published by Elsevier Ltd.

  4. Optimizing the treatment of landfill leachate by conventional Fenton and photo-Fenton processes

    Energy Technology Data Exchange (ETDEWEB)

    Hermosilla, Daphne, E-mail: dhermosilla@quim.ucm.es [Departamento de Ingenieria Quimica, Facultad de Ciencias Quimicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain); Cortijo, Manuel [U.D. Operaciones Basicas, Departamento de Ingenieria Forestal, E.T.S.I. Montes, Universidad Politecnica de Madrid, Avda. Ramiro de Maeztu s/n, 28040 Madrid (Spain); Huang, Chin Pao [Department of Civil and Environmental Engineering, 352C DuPont Hall, University of Delaware, Newark, DE 19716 (United States)

    2009-05-15

    Landfill, a matured and economically appealing technology, is the ultimate approach for the management of municipal solid wastes. However, the inevitable generation of leachate from landfill requires further treatment. Among the various leachate treatment technologies available, advanced oxidation processes (AOPs) are among powerful methods to deal with the refractory organic constituents, and the Fenton reagent has evolved as one promising AOPs for the treatment of leachates. Particularly, the combination of UV-radiation with Fenton's reagent has been reported to be a method that allows both the photo-regeneration of Fe{sup 2+} and photo-decarboxylation of ferric carboxylates. In this study, Fenton and photo-Fenton processes were fine tuned for the treatment of leachates from the Colmenar Viejo (Madrid, Spain) Landfill. Results showed that it is possible to define a set of conditions under which the same COD and TOC removals (approx 70%) could be achieved with both the conventional and photo-Fenton processes. But Fenton process generated an important quantity of iron sludge, which will require further disposal, when performed under optimal COD removal conditions. Furthermore conventional Fenton process was able to achieve slightly over an 80% COD removal from a 'young' leachate, while for 'old' and 'mixed' leachates was close to a 70%. The main advantage showed by the photo-assisted Fenton treatment of landfill leachate was that it consumed 32 times less iron and produced 25 times less sludge volume yielding the same COD removal results than a conventional Fenton treatment.

  5. Removal of Heavy Metals from Solid Wastes Leachates Coagulation-Flocculation Process

    Science.gov (United States)

    Yousefi, Z.; Zazouli, M. A.

    The main objectives of present research were to determine heavy metals (Ni, Cd, Cr, Zn and Cu) and COD concentration in raw leachate in Esfahan (Iran) composting plant and to examine the application of coagulation-flocculation process for the treatment of raw leachates. Jar-test experiments were employed in order to determine the optimum conditions (effective dosage and optimum pH) for the removal of COD and heavy metals. Alum (aluminum sulphate) and Ferric chloride were tested as conventional coagulants. Ten times had taken sampling from leachates as standard methods in the composting plant prior to composting process. The results showed that Leachate pH was 4.3-5.9 and the average was 4.98±0.62. The concentration of Leachate pollutants were more than effluent standard limits (Environment protection Agency). And also the results indicated, Cd and Zn with concentration 0.46±0.41 and 5.81±3.69 mg L-1, had minimum and maximum levels, respectively. The results of coagulation and flocculation tests showed that in optimum conditions, the removal efficiency of heavy metals and COD by using alum were 77-91 and 21%, respectively. While removal of heavy metals and COD by ferric chloride were 68-85.5% and 28%, respectively. Also the residues of heavy metals after treatment get to under of standard limits of Iran EPA. The results have indicated optimum pH of two coagulants for leachate treatment was 6.5 and 10 and also effective coagulant dosages were 1400 and 1000 mg L-1 for alum and ferric chloride, respectively. In view of economical, ferric chloride is cost benefit. The physico-chemical process may be used as a useful pretreatment step, especially for fresh leachates.

  6. Contaminants of emerging concern in fresh leachate from landfills in the conterminous United States

    Science.gov (United States)

    Masoner, Jason R.; Kolpin, Dana W.; Furlong, Edward T.; Cozzarelli, Isabelle M.; Gray, James L.; Schwab, Eric A.

    2014-01-01

    To better understand the composition of contaminants of emerging concern (CECs) in landfill leachate, fresh leachate from 19 landfills was sampled across the United States during 2011. The sampled network included 12 municipal and 7 private landfills with varying landfill waste compositions, geographic and climatic settings, ages of waste, waste loads, and leachate production. A total of 129 out of 202 CECs were detected during this study, including 62 prescription pharmaceuticals, 23 industrial chemicals, 18 nonprescription pharmaceuticals, 16 household chemicals, 6 steroid hormones, and 4 plant/animal sterols. CECs were detected in every leachate sample, with the total number of detected CECs in samples ranging from 6 to 82 (median = 31). Bisphenol A (BPA), cotinine, and N,N-diethyltoluamide (DEET) were the most frequently detected CECs, being found in 95% of the leachate samples, followed by lidocaine (89%) and camphor (84%). Other frequently detected CECs included benzophenone, naphthalene, and amphetamine, each detected in 79% of the leachate samples. CEC concentrations spanned six orders of magnitude, ranging from ng L−1 to mg L−1. Industrial and household chemicals were measured in the greatest concentrations, composing more than 82% of the total measured CEC concentrations. Maximum concentrations for three household and industrial chemicals, para-cresol (7020000 ng L−1), BPA (6380000 ng L−1), and phenol (1550000 ng L−1), were the largest measured, with these CECs composing 70% of the total measured CEC concentrations. Nonprescription pharmaceuticals represented 12%, plant/animal sterols 4%, prescription pharmaceuticals 1%, and steroid hormones amounts of precipitation had greater frequencies of CEC detections and concentrations in leachate than landfills receiving less precipitation.

  7. TU-C-HORIZONS-01: The Expanding Horizons Travel Grant Program: ePosters and Discussion

    Energy Technology Data Exchange (ETDEWEB)

    Siewerdsen, J [Johns Hopkins University, Baltimore, MD (United States); Jeraj, R [University of Wisconsin, Madison, WI (United States)

    2016-06-15

    The Expanding Horizons travel grant program provides opportunity for students and trainees to broaden the scope of scientific meetings they attend and gain insight from research outside traditional domains of medical physics. Through participation in such conferences, early-career researchers are introduced to new topics with relevance to medical physics research as a means to expand the scientific horizons of our discipline. This year, 21 Expanding Horizons travel grants were awarded, granting travel to 17 conferences, including: Radiomics, the World Molecular Imaging Society (WMIS), the 3D Printing Conference and Expo, the GPU Technology Conference, the SIAM Imaging Science Conference, the Human Brain Mapping Conference, the OSA Conference on Clinical and Translational Biophotonics, the Society for Neuroscience, the AACR Conference on Tumor Microenvironment, and the Conference on Knowledge Discovery and Data Mining. The Expanding Horizons electronic poster session gives a venue for AAPM conference attendees to meet and discuss with awardees, learn the hot topics and emerging research areas presented at these conferences, and understand the relevance to future medical physics research.

  8. TU-C-HORIZONS-01: The Expanding Horizons Travel Grant Program: ePosters and Discussion

    International Nuclear Information System (INIS)

    Siewerdsen, J; Jeraj, R

    2016-01-01

    The Expanding Horizons travel grant program provides opportunity for students and trainees to broaden the scope of scientific meetings they attend and gain insight from research outside traditional domains of medical physics. Through participation in such conferences, early-career researchers are introduced to new topics with relevance to medical physics research as a means to expand the scientific horizons of our discipline. This year, 21 Expanding Horizons travel grants were awarded, granting travel to 17 conferences, including: Radiomics, the World Molecular Imaging Society (WMIS), the 3D Printing Conference and Expo, the GPU Technology Conference, the SIAM Imaging Science Conference, the Human Brain Mapping Conference, the OSA Conference on Clinical and Translational Biophotonics, the Society for Neuroscience, the AACR Conference on Tumor Microenvironment, and the Conference on Knowledge Discovery and Data Mining. The Expanding Horizons electronic poster session gives a venue for AAPM conference attendees to meet and discuss with awardees, learn the hot topics and emerging research areas presented at these conferences, and understand the relevance to future medical physics research.

  9. Hawking radiation of an apparent horizon in a FRW universe

    International Nuclear Information System (INIS)

    Cai Ronggen; Cao Liming; Hu Yapeng

    2009-01-01

    Hawking radiation is an important quantum phenomenon of a black hole, which is closely related to the existence of an event horizon of a black hole. The cosmological event horizon of de Sitter space is also of Hawking radiation with a thermal spectrum. By use of the tunneling approach, we show that there is indeed a Hawking radiation with temperature, T=1/(2πr-tilde A , for a locally defined apparent horizon of a Friedmann-Robertson-Walker universe with any spatial curvature, where r-tilde A is the apparent horizon radius. Thus we fill in the gap existing in the literature investigating the relation between the first law of thermodynamics and Friedmann equations; there the apparent horizon is assumed to have such a temperature without any proof. In addition, we stress the implication of the Hawking temperature associated with the apparent horizon.

  10. Hawking radiation from the cosmological horizon in a FRW universe

    International Nuclear Information System (INIS)

    Hu Yapeng

    2011-01-01

    It is well known that there is a Hawking radiation from the cosmological horizon of the de Sitter spacetime, and the de Sitter spacetime can be a special case of a FRW universe. Therefore, there may be a corresponding Hawking radiation in a FRW universe. Indeed, there have been several clues showing that there is a Hawking radiation from the apparent horizon of a FRW universe. In our Letter, however, we find that the Hawking radiation may come from the cosmological horizon. Moreover, we also find that the Hawking radiation from the apparent horizon of a FRW universe in some previous works can be a special case in our result, and the condition is that the variation rate of cosmological horizon r . H is zero. Note that, this condition is also consistent with the underlying integrable condition in these works from the apparent horizon.

  11. Classification of Near-Horizon Geometries of Extremal Black Holes

    Directory of Open Access Journals (Sweden)

    Hari K. Kunduri

    2013-09-01

    Full Text Available Any spacetime containing a degenerate Killing horizon, such as an extremal black hole, possesses a well-defined notion of a near-horizon geometry. We review such near-horizon geometry solutions in a variety of dimensions and theories in a unified manner. We discuss various general results including horizon topology and near-horizon symmetry enhancement. We also discuss the status of the classification of near-horizon geometries in theories ranging from vacuum gravity to Einstein–Maxwell theory and supergravity theories. Finally, we discuss applications to the classification of extremal black holes and various related topics. Several new results are presented and open problems are highlighted throughout.

  12. Sedimentation and diagenesis at a Late Cambrian biomere extinction horizon

    Energy Technology Data Exchange (ETDEWEB)

    Grimm, K.A.; Miller, J.F.; Taylor, J.F.

    1985-01-01

    The base of the Eurekia apopsis Subzone of the Saukia Zone, slightly below the present Cambrian-Ordovician boundary, has been interpreted as a biomere extinction crisis for trilobites and conodonts. This boundary can be recognized to within two centimeters in platform carbonates in Utah, Nevada, Texas, and Oklahoma. Regional stratigraphy in West Utah reveals that this extinction horizon occurs within a shoaling upward sequence in which sedimentation was predominantly episodic. Shallow subtidal sedimentation, producing bioturbated mixed-skeletal wackestones and graded intraclastic grainsupportstones (tempestites), shifted to peritidal sedimentation through the boundary interval and for the duration of the E. apopsis Subzone. Associated lithofacies include sponge-dominated thrombolite mounds with tidal channels, sublittoral stromatolite reefs, and a restricted marine lagoon. The base of the E. apopsis Subzone in West Utah is a sharp contact but is interpreted as neither a disconformity nor a surface of subaerial exposure. In Texas, this boundary is a planar disconformity between biosparites. The bed underlying this surface displays features that reflect wholesale aragonite dissolution followed by two stages of inferred meteroic phreatic cementation. The surface is well washed and provided a clean substrate for epitaxial cementation across the boundary. The overlying basal strata of the E. apopsis Subzone are cemented with marine phreatic non-ferroan calcite and contain faunas that are strikingly dissimilar to those below.

  13. Analysis of bio-obtainable endocrine disrupting metals in river water and sediment, sewage influent/effluent, sludge, leachate, and concentrated leachate, in the irish midlands shannon catchment.

    LENUS (Irish Health Repository)

    Reid, Antoinette M

    2009-01-01

    The application of an acid digestion and subsequent solid-phase extraction (SPE) procedure were implemented as preliminary treatments prior to quantifying the levels of potentially endocrine disrupting metals (EDMs) in a variety of solid and liquid matrices. These included (solid) river sediment, leachate sediment and sewage sludge and also (liquid) river water, landfill leachate, concentrated leachate, sewage influent, and sewage effluent, sampled in the Irish Midlands. The total concentrations of cobalt (Co), cadmium (Cd), copper (Cu), chromium (Cr), nickel (Ni), lead (Pb), zinc (Zn), and manganese (Mn), after extraction and preconcentration, were determined by atomic absorption spectroscopy (AAS). Mercury (Hg) in sediment and sludge was determined using cold-vapour atomic fluorescence spectroscopy (AFS). For sewage sludge maximum values (mg\\/kg(dw)) of 4700 Ni, 1642 Mn, 100.0 Cd, 3400 Zn, 36.70 Co, 750.0 Pb, 485.8 Cr, and 1003 Cu were determined whilst in leachate sediment, maximum values (mg\\/kg(dw)) of 32.10 Ni, 815.0 Mn, 32.78 Cd, 230.3 Zn, 26.73 Co, 3525 Pb, 124.9 Cr, and 50.13 Cu were found. Over several months, the data showed elevated levels in sewage influents, effluents, and sludges compared to a battery of adjacent river water samples and corresponding sediments. There was a definite trend for target values for sediments to be exceeded, while intervention values were only exceeded for cadmium. Overall the pattern in terms of concentration was sewage > leachate > river matrices. A nonparametric assessment of the effect of sewage treatment method on median metal levels in sludge revealed statistically significant differences at the 95% level of confidence for Co, Cr, and Hg and at the 90% level of confidence for Cd.

  14. NEW HORIZONS PEPSSI JUPITER ENCOUNTER V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains Calibrated data taken by the New Horizons Pluto Energetic Particle Spectrometer Science Investigation instrument during the Jupiter encounter...

  15. NEW HORIZONS PEPSSI PLUTO ENCOUNTER CALIBRATED V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains Calibrated data taken by the New Horizons Pluto Energetic Particle Spectrometer Science Investigation instrument during the Pluto encounter...

  16. NEW HORIZONS PEPSSI JUPITER ENCOUNTER V1.1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains Calibrated data taken by the New Horizons Pluto Energetic Particle Spectrometer Science Investigation instrument during the Jupiter encounter...

  17. New Worlds, New Horizons in Astronomy and Astrophysics

    National Research Council Canada - National Science Library

    2010-01-01

    .... Based on a broad and comprehensive survey of scientific opportunities, infrastructure, and organization in a national and international context, New Worlds, New Horizons in Astronomy and Astrophysic...

  18. NEW HORIZONS MVIC JUPITER ENCOUNTER V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains Calibrated data taken by the New Horizons Multispectral Visible Imaging Camera instrument during the Jupiter encounter mission phase.

  19. Attenuation of landfill leachate by UK Triassic sandstone aquifer materials. 1. Fate of inorganic pollutants in laboratory columns

    Science.gov (United States)

    Thornton, Steven F.; Tellam, John H.; Lerner, David N.

    2000-05-01

    The attenuation of inorganic contaminants in acetogenic and methanogenic landfill leachate by calcareous and carbonate-deficient, oxide-rich Triassic sandstone aquifer materials from the English Midlands was examined in laboratory columns. Aqueous equilibrium speciation modelling, simple transport modelling and chemical mass balance approaches are used to evaluate the key processes and aquifer geochemical properties controlling contaminant fate. The results indicate that leachate-rock interactions are dominated by ion-exchange processes, acid-base and redox reactions and sorption/precipitation of metal species. Leachate NH 4 is attenuated by cation exchange with the aquifer sediments; however, NH 4 migration could be described with a simple model using retardation factors. Organic acids in the acetogenic leachate buffered the system pH at low levels during flushing of the calcareous aquifer material. In contrast, equilibrium with Al oxyhydroxide phases initially buffered pH (˜4.5) during flushing of the carbonate-deficient sandstone with methanogenic leachate. This led to the mobilisation of sorbed and oxide-bound heavy metals from the aquifer sediment which migrated as a concentrated pulse at the leachate front. Abiotic reductive dissolution of Mn oxyhydroxides on each aquifer material by leachate Fe 2+ maintains high concentrations of dissolved Mn and buffers the leachate inorganic redox system. This feature is analogous to the Mn-reducing zones found in leachate plumes and in the experiments provides a sink for the leachate Fe load and other heavy metals. The availability of reactive solid phase Mn oxyhydroxides limits the duration of redox buffering and Fe attenuation by these aquifer sediments. Aquifer pH and redox buffering capacity exert a fundamental influence on leachate inorganic contaminant fate in these systems. The implications for the assessment of aquifer vulnerability at landfills are discussed and simple measurements of aquifer properties which

  20. Impact of landfill leachate on the groundwater quality: A case study in Egypt

    Directory of Open Access Journals (Sweden)

    Magda M. Abd El-Salam

    2015-07-01

    Full Text Available Alexandria Governorate contracted an international company in the field of municipal solid waste management for the collection, transport and disposal of municipal solid waste. Construction and operation of the sanitary landfill sites were also included in the contract for the safe final disposal of solid waste. To evaluate the environmental impacts associated with solid waste landfilling, leachate and groundwater quality near the landfills were analyzed. The results of physico-chemical analyses of leachate confirmed that its characteristics were highly variable with severe contamination of organics, salts and heavy metals. The BOD5/COD ratio (0.69 indicated that the leachate was biodegradable and un-stabilized. It was also found that groundwater in the vicinity of the landfills did not have severe contamination, although certain parameters exceeded the WHO and EPA limits. These parameters included conductivity, total dissolved solids, chlorides, sulfates, Mn and Fe. The results suggested the need for adjusting factors enhancing anaerobic biodegradation that lead to leachate stabilization in addition to continuous monitoring of the groundwater and leachate treatment processes.

  1. Effect on municipal waste combustion ash monofill leachate on selected containment barrier components

    International Nuclear Information System (INIS)

    Carson, D.A.; Janszen, T.A.

    1992-01-01

    This study was initiated to investigate the effects of municipal waste combustion (MWC) ash monofill leachate on lining components of an MWC monofill. This included geosynthetic materials and natural clay (soil) liners. The ability of these materials to perform their design function for the life of the facility and post-closure period is best estimated through accelerated test methods described herein. The study consisted of two separate testing efforts, one aimed at evaluating selected natural clay linings and the other at evaluating selected geosynthetics. Both tests were performed using the same waste. Leachate was collected from two sources, one considered modern, and the other considered older technology. Site A was a state-of-the-art MWC ash monofill leachate facility. This facility had a scrubber, and ash disposed of in the monofill contained bottom ash, fly ash, and scrubber residue. Site B was an older MWC ash monofill leachate facility. This facility did not have a scrubber. Ash disposed of in the monofill contained bottom ash and fly ash. The following generic geomembrane types were selected at random to be tested: high-density polyethylene (HDPE), reinforced chlorosulfonated polyethylene (CSPE-R), and polyvinyl chloride (PVC). One filtration/separation geosynthetic was tested: a nonwoven polyester geotextile. Three compacted soils (Illinois, Lufkin, and Nacogodoches) were evaluated to determine their resistance of the two MWC ash leachates

  2. Co-treatment of landfill leachate and domestic wastewater using a submerged aerobic biofilter.

    Science.gov (United States)

    Ferraz, F M; Povinelli, J; Pozzi, E; Vieira, E M; Trofino, J C

    2014-08-01

    This study used a pilot-scale submerged aerobic biofilter (SAB) to evaluate the co-treatment of domestic wastewater and landfill leachate that was pre-treated by air stripping. The leachate tested volumetric ratios were 0, 2, and 5%. At a hydraulic retention time of 24 h, the SAB was best operated with a volumetric ratio of 2% and removed 98% of the biochemical oxygen demand (BOD), 80% of the chemical oxygen demand (COD) and dissolved organic carbon (DOC), and 90% of the total suspended solids (TSS). A proposed method, which we called the "equivalent in humic acid" (Eq.HA) approach, indicated that the hardly biodegradable organic matter in leachate was removed by partial degradation (71% of DOC Eq.HA removal). Adding leachate at a volumetric ratio of 5%, the concentration of the hardly biodegradable organic matter was decreased primarily as a result of dilution rather than biodegradation, which was confirmed by Fourier transform infrared (FTIR) spectroscopy. The total ammoniacal nitrogen (TAN) was mostly removed (90%) by nitrification, and the SAB performances at the volumetric ratios of 0 and 2% were equal. For the three tested volumetric ratios of leachate (0, 2, and 5%), the concentrations of heavy metals in the treated samples were below the local limits. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. THE "CHEMICAL OXYGEN DEMAND / TOTAL VOLATILE ACIDS" RATIO AS AN ANAEROBIC TREATABILITY INDICATOR FOR LANDFILL LEACHATES

    Directory of Open Access Journals (Sweden)

    R. C. Contrera

    2015-03-01

    Full Text Available Abstract In some operational circumstances a fast evaluation of landfill leachate anaerobic treatability is necessary, and neither Biochemical Methane Potential nor BOD/COD ratio are fast enough. Looking for a fast indicator, this work evaluated the anaerobic treatability of landfill leachate from São Carlos-SP (Brazil in a pilot scale Anaerobic Sequence Batch Biofilm Reactor (AnSBBR. The experiment was conducted at ambient temperature in the landfill area. After the acclimation, at a second stage of operation, the AnSBBR presented efficiency above 70%, in terms of COD removal, utilizing landfill leachate without water dilution, with an inlet COD of about 11,000 mg.L-1, a TVA/COD ratio of approximately 0.6 and reaction time equal to 7 days. To evaluate the landfill leachate biodegradability variation over time, temporal profiles of concentration were performed in the AnSBBR. The landfill leachate anaerobic biodegradability was verified to have a direct and strong relationship to the TVA/COD ratio. For a TVA/CODTotal ratio lower than 0.20, the biodegradability was considered low, for ratios between 0.20 and 0.40 it was considered medium, and above 0.40 it was considered high.

  4. An overview of municipal solid waste management and landfill leachate treatment: Malaysia and Asian perspectives.

    Science.gov (United States)

    Kamaruddin, Mohamad Anuar; Yusoff, Mohd Suffian; Rui, Lo Ming; Isa, Awatif Md; Zawawi, Mohd Hafiz; Alrozi, Rasyidah

    2017-12-01

    Currently, generation of solid waste per capita in Malaysia is about 1.1 kg/day. Over 26,500 t of solid waste is disposed almost solely through 166 operating landfills in the country every day. Despite the availability of other disposal methods, landfill is the most widely accepted and prevalent method for municipal solid waste (MSW) disposal in developing countries, including Malaysia. This is mainly ascribed to its inherent forte in terms cost saving and simpler operational mechanism. However, there is a downside. Environmental pollution caused by the landfill leachate has been one of the typical dilemmas of landfilling method. Leachate is the liquid produced when water percolates through solid waste and contains dissolved or suspended materials from various disposed materials and biodecomposition processes. It is often a high-strength wastewater with extreme pH, chemical oxygen demand (COD), biochemical oxygen demand (BOD), inorganic salts and toxicity. Its composition differs over the time and space within a particular landfill, influenced by a broad spectrum of factors, namely waste composition, landfilling practice (solid waste contouring and compacting), local climatic conditions, landfill's physico-chemical conditions, biogeochemistry and landfill age. This paper summarises an overview of landfill operation and leachate treatment availability reported in literature: a broad spectrum of landfill management opportunity, leachate parameter discussions and the way forward of landfill leachate treatment applicability.

  5. Application of Electrochemical Process in Removal of Heavy Metals from Landfill Leachate

    Directory of Open Access Journals (Sweden)

    Mostafaii Gh.1 PhD,

    2016-08-01

    Full Text Available Aims Municipal landfill leachate contains high concentrations of heavy metals, organics, ammonia. The efficeincy of electrochemically removal of heavy metals from landfill leachate was studied. Materials & Methods The leachate was obtained from Kahrizak landfill in south of Tehran. The experiments were carried out by batch process. The 2liter batch reactor was made of glass. There were eight anodes and cathodes electrodes. The electrodes were placed vertically parallel to each other and they were connected to a digital DC power supply. The pH and conductivity were adjusted to a desirable value using NaOH or H2SO4, and NaCl. All the runs were performed at constant temperature of 25°C. In each run, 1.5liter of the leachate was placed into the electrolytic cell. Samples were extracted every 10min and then filtered through a mixed cellulose acetate membrane (0.42μm. The amount of Lead, Zinc and Nickel removal was measured at pH=7 and in current density of 0.5, 0.75, and 1A. Findings When current density and time reaction increased, removal efficiency of heavy metals such as Lead, Zinc and Nickel increased. At initial pH=7, density 1A and reaction time= 60min, Lead, Nickel and Zinc were removed up to 86, 93 and 95%, respectively. Conclusion Electrochemical process can be proposed as a suitable technique to remove heavy metal from landfill leachate.

  6. REMOVAL OF PHENOL AND SURFACTANT FROM LANDFILL LEACHATE BY COAGULATION-FLOCCULATION PROCESS

    Directory of Open Access Journals (Sweden)

    H. BAKRAOUY

    2016-02-01

    Full Text Available Following the action of rainfall and natural fermentation, the stored waste produces a liquid fraction called leachate. This leachate is rich in organic matter (biodegradable but also refractory and trace elements. There are many techniques of treating the leachate, in particular, biological, physicochemical, membrane processes. The choice of a technique instead of another depends on several parameters including: the age of the leachate, composition... In this work we applied a coagulation-flocculation process to treat intermediate landfill leachate of Rabat city with a combined ferric chloride coagulant and a polymer flocculant. We were inspired by full factorial design, including twenty five experiments, to determine optimal dosages of coagulant and flocculant. We operate at pH 8.4, the best removal efficiencies obtained were 88 % for Turbidity, 98 % for Phenol and 82 % for surfactant. The optimum dosages values determined by this study were 13.2 g∙L-1 of coagulant, 62 mL∙L-1 of flocculant.

  7. Sanitary landfill leachate as a source of nutrients on the initial growth of sunflower plants

    Directory of Open Access Journals (Sweden)

    Francisco H. Nunes Júnior

    Full Text Available ABSTRACT The aim of this study was to evaluate the initial growth of sunflower seedlings under different concentrations of sanitary landfill leachate, considering the feasibility of its use as source of nutrients for agricultural production. Biometric and vigor variables were analyzed through the measurements of collar diameter, shoot height, number of leaves and shoot and root fresh and dry matters, from January to February 2015. The experimental design was completely randomized in a 5 x 4 factorial scheme: five leachate concentrations (0, 40, 60, 80 and 100 kg N ha-1 x four harvest periods (14, 21, 25 and 29 days after sowing, with five replicates each containing two plants. The data were subjected to analysis of variance and polynomial regression, and the results of the last harvest (29 DAS were compared by Tukey test (p ≤ 0.05. The use of sanitary landfill leachate increased all analyzed variables in sunflower plants when compared to the control plants (without leachate, especially in the treatment of 100 kg N ha-1. There was no inhibitory effect of the leachate on the initial growth of sunflower seedlings under adopted experimental conditions.

  8. BIOLEACH: Coupled modeling of leachate and biogas production on solid waste landfills

    Science.gov (United States)

    Rodrigo-Clavero, Maria-Elena; Rodrigo-Ilarri, Javier

    2015-04-01

    One of the most important factors to address when performing the environmental impact assessment of urban solid waste landfills is to evaluate the leachate production. Leachate management (collection and treatment) is also one of the most relevant economical aspects to take into account during the landfill life. Leachate is formed as a solution of biological and chemical components during operational and post-operational phases on urban solid waste landfills as a combination of different processes that involve water gains and looses inside the solid waste mass. Infiltration of external water coming from precipitation is the most important component on this water balance. However, anaerobic waste decomposition and biogas formation processes play also a role on the balance as water-consuming processes. The production of leachate one biogas is therefore a coupled process. Biogas production models usually consider optimal conditions of water content on the solid waste mass. However, real conditions during the operational phase of the landfill may greatly differ from these optimal conditions. In this work, the first results obtained to predict both the leachate and the biogas production as a single coupled phenomenon on real solid waste landfills are shown. The model is applied on a synthetic case considering typical climatological conditions of Mediterranean catchments.

  9. Investigating Potential Toxicity of Leachate from Wood Chip Piles Generated by Roadside Biomass Operations

    Directory of Open Access Journals (Sweden)

    John Rex

    2016-02-01

    Full Text Available Roadside processing of wood biomass leaves chip piles of varying size depending upon whether they were created for temporary storage, spillage, or equipment maintenance. Wood chips left in these piles can generate leachate that contaminates streams when processing sites are connected to waterways. Leachate toxicity and chemistry were assessed for pure aspen (Populus tremuloides Michx., lodgepole pine (Pinus contorta Dougl., hybrid white spruce (Picea engelmannii x glauca Parry, and black spruce (Picea mariana (Mill. Britton as well as from two wood chipping sites using mixes of lodgepole pine and hybrid or black spruce. Leachate was generated using rainfall simulation, a static 28-day laboratory assay, and a field-based exposure. Leachate generated by these exposures was analyzed for organic matter content, phenols, ammonia, pH, and toxicity. Findings indicate that all wood chip types produced a toxic leachate despite differences in their chemistry. The consistent toxicity response highlights the need for runoff management that will disconnect processing sites from aquatic environments.

  10. Fertigation of Brassica rapa L. using treated landfill leachate as a nutrient recycling option

    Directory of Open Access Journals (Sweden)

    Frank O. Alaribe

    2016-03-01

    Full Text Available Optimising nutrient availability and minimising plant metal contamination are vital in sustainable agriculture. This paper reports experiments in which treated leachate was used at different concentrations with predetermined N content for fertigation of Brassica rapa L. (leafy vegetable. An inorganic fertiliser, with N content equivalent to the leachate amount, was also prepared, as well as a control. Growth (leaf length, leaf width and stem height, harvest parameters (total number of leaves, root length and root dry weight and specific growth rates (mm/day were determined for three consecutive seasons. The dry weights of leaves, roots and stems in the leachate treatments were within the ranges of 1.95–3.60 g, 1.18–3.60 g and 0.33–1.37 g, with biomasses of 1.75 g, 1.14 g and 0.2 g, respectively, which were higher than those of the control. B. rapa L. fertigated with 25% diluted treated leachate recorded high specific growth rate and a leaf length of 0.53 mm/day and 0.23.17±0.58 cm, respectively (%N=0.023; p"less than"0.05. The maximum permissible mineral concentration set by the Food and Agricultural Organization of the United Nations/World Health Organization (FAO/WHO was compared with that of the grown plants. Treated leachate can increase plant nutrient content.

  11. Global embedding of the Kerr black hole event horizon into hyperbolic 3-space

    International Nuclear Information System (INIS)

    Gibbons, G. W.; Herdeiro, C. A. R.; Rebelo, C.

    2009-01-01

    An explicit global and unique isometric embedding into hyperbolic 3-space, H 3 , of an axi-symmetric 2-surface with Gaussian curvature bounded below is given. In particular, this allows the embedding into H 3 of surfaces of revolution having negative, but finite, Gaussian curvature at smooth fixed points of the U(1) isometry. As an example, we exhibit the global embedding of the Kerr-Newman event horizon into H 3 , for arbitrary values of the angular momentum. For this example, considering a quotient of H 3 by the Picard group, we show that the hyperbolic embedding fits in a fundamental domain of the group up to a slightly larger value of the angular momentum than the limit for which a global embedding into Euclidean 3-space is possible. An embedding of the double-Kerr event horizon is also presented, as an example of an embedding that cannot be made global.

  12. Pseudomonas chengduensis sp. nov., isolated from landfill leachate.

    Science.gov (United States)

    Tao, Yong; Zhou, Yan; He, Xiaohong; Hu, Xiaohong; Li, Daping

    2014-01-01

    Strain MBR(T) was isolated from landfill leachate in a solid-waste disposal site in Chengdu, Sichuan, China. An analysis of 16S rRNA gene sequences revealed that the isolate was closely related to members of the genus Pseudomonas, sharing the highest sequence similarities with Pseudomonas toyotomiensis HT-3(T) (99.8 %), Pseudomonas alcaliphila AL15-21(T) (99.7 %) and Pseudomonas oleovorans ATCC 8062(T) (99.4 %). Multi-locus sequence analysis based on three housekeeping genes (gyrB, rpoB and rpoD) provided higher resolution at the species level than that based on 16S rRNA gene sequences, which was further confirmed by less than 70 % DNA-DNA relatedness between the new isolate and P. toyotomiensis HT-3(T) (61.3 %), P. alcaliphila AL15-21(T) (51.5 %) and P. oleovorans ATCC 8062(T) (57.8 %). The DNA G+C content of strain MBR(T) was 61.9 mol% and the major ubiquinone was Q-9. The major cellular fatty acids (>10 %) were C18 : 1ω7c and/or C18 : 1ω6c, C16 : 0, and C16 : 1ω7c and/or C16 : 1ω6c. Polyphasic analysis indicates that strain MBR(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas chengduensis sp. nov. is proposed. The type strain is MBR(T) ( = CGMCC 2318(T) = DSM 26382(T)).

  13. Clarification of leachate from reclaimed ground by electron beam irradiation

    International Nuclear Information System (INIS)

    Yamazaki, Masao; Sawai, Teruko; Shimokawa, Toshinari; Sawai, Takeshi

    1985-01-01

    To decompose organic matters such as humic acid and fulvous acid in the leachate from reclaimed ground, an electron beam irradiation technique was examined because of availability of higher dose rate than a 60 Co γ-ray source. This paper describes results of the above-mentioned preliminary examination. Test water was collected from No.15 dumping site at the Tokyo Bay. Irradiation sample was prepared by filtration with a filter and decarbonation with sulfuric acid. Fulvous acid solution by eliminating humic acid was also served for the examination. Electron beam irradiation of the sample solution was made with a Van de Graaf accelerator by 1.5 MeV, 140 Gy/sec of irradiation condition and with a dynamitron by 2.0 MeV, 25 kGy/pass of the condition. It was clarified that oxygen bubbling velocity during the irradiation did not affect much for the decrease rate of total organic matters (TOC) within 0.5 to 3.0 1/min of an experimental condition. As for radiation doses and TOC decrease, TOC was decreased much for lower dose rate irradiation (Van de Graaf accelerator), lower initial TOC concentration, or addition of hydrogen peroxide. For the combined treatment of radiation and flocculation to aim at irradiation dose decrease, fulvous acid solution was served for the test. Lower dose irradiation with a 60 Co source showed better TOC elimination and it was concluded that combination with flocculation was effective for the dose reduction. It was also found experimentally that TOC decrease behavior by the both radiation source was different due to temperature effect and further study should be made for the development of the practical electron beam irradiation technique. (Takagi, S.)

  14. Assessment of the level of environmental pollution due to leachate migration from the closed Mallam SCC waste disposal site Accra-Ghana

    International Nuclear Information System (INIS)

    Odai, R. N.

    2013-07-01

    The closed Mallam State Corporation (SCC) waste disposal site is one of the many unengineered and improperly decommissioned municipal solid waste (MSW) landfills in Accra, Ghana. The site served as a landfill site for the Accra Metropolitan Assembly (A.M.A) for 7 years and received variety of solid waste from the A.M.A and other neighbouring municipal assemblies. Leachate management plans were however, not implemented. Untreated leachate from the waste disposal site flows through the human settlements around the waste disposal site and enter into nearby surface water (Bawere Stream). The site was closed in 2001 after several agitations from the people living around, coupled with the fact that it was full to its maximum. The waste disposal site was not properly decommissioned prior to its closure. As a result, untreated leachate from the site still flows through the human settlement and enter the Bawere Stream. The research was carried out to assess the level of contamination of surface water, soil and groundwater due to leachate migration from the closed waste disposal site with emphasis on major ions (Na + , K + , Ca 2+ , Mg 2+ , Cl - , HCO 3 - SO 4 2- , NO 3 - and PO 4 3- ) and trace elements (Fe, Pb, Cd, Cr, Mn, As, Zn, Hg, Cu and Co). Major ions were measured using conventional methods. Trace element concentrations were determined using Atomic Absorption Spectrometry. Stable isotopic composition (δ 18 O and δ 2 H) of the surface water, soil and groundwater were determined using the Liquid-Water Stable Isotope Analyzer (Off-Axis Integrated Cavity Output Spectroscopy via laser absorption). Results showed high level of contamination of the surface water. The mean concentrations of Na + , K + , Fe, Pb, Cd and Mn (388 mg/L, 53 mg/L, 0.046 mg/L, 0.229 mg/L and 0.234 mg/L respectively) in the surface water were above the maximum permissible limit of the WHO (1996) guideline for drinking water. The mean δ 18 O and δ 2 H values of the surface water were -1.59

  15. CERN encourages girls to "expand their horizons"

    CERN Document Server

    François Briard

    2015-01-01

    On 14 November, CERN took part for the fourth time in "Élargis tes horizons" (see here), a conference organised every two years at Geneva University for girls from the local region aged 11 to 14 aiming to encourage them to take up studies and careers in the scientific and technical domains.   Claude Sanz (left), a fellow in the EN Department, explaining to three girls how to build a particle accelerator in a salad bowl. This year, young physicists and engineers from ATLAS and CMS ran three workshops: "Seeing the invisible using a cloud chamber", "Great cold fun and treats with liquid nitrogen" and "Build your own accelerator in a salad bowl!" CERN was also represented at the Forum de Découverte, represented by the Diversity Office and the Medialab team, presenting the "Higgnite" interactive experiment, which illustrates the principle of the Higgs field. More...

  16. THERMAL CONDUCTIVITY OF THE POTENTIAL REPOSITORY HORIZON

    Energy Technology Data Exchange (ETDEWEB)

    J.E. BEAN

    2004-09-27

    The primary purpose of this report is to assess the spatial variability and uncertainty of bulk thermal conductivity in the host horizon for the repository at Yucca Mountain. More specifically, the lithostratigraphic units studied are located within the Topopah Spring Tuff (Tpt) and consist of the upper lithophysal zone (Tptpul), the middle nonlithophysal zone (Tptpmn), the lower lithophysal zone (Tptpll), and the lower nonlithophysal zone (Tptpln). Design plans indicate that approximately 81 percent of the repository will be excavated in the Tptpll, approximately 12 percent in the Tptpmn, and the remainder in the Tptul and Tptpln (BSC 2004 [DIRS 168370]). This report provides three-dimensional geostatistical estimates of the bulk thermal conductivity for the four stratigraphic layers of the repository horizon. The three-dimensional geostatistical estimates of matrix and lithophysal porosity, dry bulk density, and matrix thermal conductivity are also provided. This report provides input to various models and calculations that simulate heat transport through the rock mass. These models include the ''Drift Degradation Analysis, Multiscale Thermohydrologic Model, Ventilation Model and Analysis Report, Igneous Intrusion Impacts on Waste Packages and Waste Forms, Drift-Scale Coupled Processes (DST and TH Seepage) Models'', and ''Drift Scale THM Model''. These models directly or indirectly provide input to the total system performance assessment (TSPA). The main distinguishing characteristic among the lithophysal and nonlithophysal units is the percentage of large-scale (centimeters-meters) voids within the rock. The Tptpul and Tptpll, as their names suggest, have a higher percentage of lithophysae than the Tptpmn and the Tptpln. Understanding the influence of the lithophysae is of great importance to understanding bulk thermal conductivity.

  17. Horizons of semiclassical black holes are cold

    International Nuclear Information System (INIS)

    Brustein, Ram; Medved, A.J.M.

    2014-01-01

    We calculate, using our recently proposed semiclassical framework, the quantum state of the Hawking pairs that are produced during the evaporation of a black hole (BH). Our framework adheres to the standard rules of quantum mechanics and incorporates the quantum fluctuations of the collapsing shell spacetime in Hawking’s original calculation, while accounting for back-reaction effects. We argue that the negative-energy Hawking modes need to be regularly integrated out; and so these are effectively subsumed by the BH and, as a result, the number of coherent negative-energy modes N coh at any given time is parametrically smaller than the total number of the Hawking particles N total emitted during the lifetime of the BH. We find that N coh is determined by the width of the BH wavefunction and scales as the square root of the BH entropy. We also find that the coherent negative-energy modes are strongly entangled with their positive-energy partners. Previously, we have found that N coh is also the number of coherent outgoing particles and that information can be continually transferred to the outgoing radiation at a rate set by N coh . Our current results show that, while the BH is semiclassical, information can be released without jeopardizing the nearly maximal inside-out entanglement and imply that the state of matter near the horizon is approximately the vacuum. The BH firewall proposal, on the other hand, is that the state of matter near the horizon deviates substantially from the vacuum, starting at the Page time. We find that, under the usual assumptions for justifying the formation of a firewall, one does indeed form at the Page time. However, the possible loophole lies in the implicit assumption that the number of strongly entangled pairs can be of the same order of N total

  18. Low-level radioactive waste disposal operations worldwide, with special reference to organic compounds in leachates and gases

    International Nuclear Information System (INIS)

    Rushbrook, P.E.; McGahan, D.J.

    1988-01-01

    Low- and intermediate-level radioactive wastes are defined and ground disposal practices worldwide are discussed. The organic content of low-level wastes is tabulated and the organic composition of leachates and gaseous emissions from low-level wastes in the U.K. and U.S.A. are discussed. The radionuclide content of these leachates is tabulated. (U.K.)

  19. Evaluation of leachate emissions from crushed rock and municipal solid waste incineration bottom ash used in road construction.

    Science.gov (United States)

    Lidelöw, S; Lagerkvist, A

    2007-01-01

    Three years of leachate emissions from municipal solid waste incineration bottom ash and crushed rock in a full-scale test road were evaluated. The impact of time, construction design, and climate on the emissions was studied, and the predicted release from standard leaching tests was compared with the measured release from the road. The main pollutants and their respective concentrations in leachate from the roadside slope were Al (12.8-85.3 mg l(-1)), Cr (2-125 microg l(-1)), and Cu (0.15-1.9 mg l(-1)) in ash leachate and Zn (1-780 microg l(-1)) in crushed rock leachate. From the ash, the initial Cl(-) release was high ( approximately 20 g l(-1)). After three years, the amount of Cu and Cl(-) was in the same range in both leachates, while that of Al and Cr still was more than one order of magnitude higher in ash leachate. Generally, the release was faster from material in the uncovered slopes than below the pavement. Whether the road was asphalted or not, however, had minor impacts on the leachate quality. During rain events, diluted leachates with respect to, e.g., salts were observed. The leaching tests failed to simulate field leaching from the crushed rock, whereas better agreement was observed for the ash. Comparisons of constituent release from bottom ash and conventional materials solely based on such tests should be avoided.

  20. Treatment of leachates of sanitary landfills of urban solid wastes. Tratamiento de lixiviados de vertederos controlados de residuos solidos urbanos

    Energy Technology Data Exchange (ETDEWEB)

    Iza Lopez, J. (Departamento de Ingenieria Quimica y de Medio Ambiente, ETSII, Bilbao (Spain))

    1994-01-01

    The method more used for Urban Solid Wastes is the sanitary landfill. Its management is similar to the industrial process plant. The minimization techniques of wastes are applicated to reduce the environmental impact and to increase the degradation process in order to improve the biogas as alternative energy. This article analyzes the anaerobic digestion, the leachates characterization and treatment of leachates. (Author)

  1. Occurrence, characteristics and leakage of polybrominated diphenyl ethers in leachate from municipal solid waste landfills in China

    International Nuclear Information System (INIS)

    Li, Ying; Li, Jinhui; Deng, Chao

    2014-01-01

    Raw leachate samples were collected from various municipal solid waste (MSW) landfills in a densely populated city in North China to measure the levels and compositional patterns of polybrominated diphenyl ethers (PBDEs) in leachate. The total concentration of PBDEs ranged from 4.0 to 351.2 ng/L, with an average of 73.0 ng/L. BDE-209 dominated the congeners in most of the samples, followed by BDE-47 and -99. Higher PBDEs concentrations were found in leachate from younger landfill facilities in the urban area. Pearson correlation analysis implied a potential dependence of the PBDEs level on landfill age, suspended solids and dissolved organic carbon, while the results of principal component analysis (PCA) suggested potential origins and transportation of PBDEs in leachate. The Monte Carlo method was adopted to estimate the annual leakage of PBDEs into the underground environment nationwide, based on two main scenarios: simple landfills with inadequate liner systems and composite-lined landfills with defective geomembranes. -- Highlights: • Levels and congener patterns of PBDEs in landfill leachate from China are measured. • Pollution loading of PBDEs in leachate is identified through comparative analysis. • Leachate properties perform moderate impact on the occurrence of PBDEs. • Both commercial and decomposition origins contribute to lower brominated congeners. • Leakage rate of PBDEs due to inadequate liner is estimated nationwide. -- This paper determined the levels and distribution of PBDEs in MSW landfill leachate and predicted the leakage of PBDEs from sanitary landfills into the underground environment across China

  2. Study on detecting leachate leakage of municipal solid waste landfill site.

    Science.gov (United States)

    Liu, Jiangang; Cao, Xianxian; Ai, Yingbo; Zhou, Dongdong; Han, Qiting

    2015-06-01

    The article studies the detection of the leakage passage of leachate in a waste landfill dam. The leachate of waste landfill has its own features, like high conductivity, high chroma and an increasing temperature, also, the horizontal flow velocity of groundwater on the leakage site increases. This article proposes a comprehensive tracing method to identify the leakage site of an impermeable membrane by using these features. This method has been applied to determine two leakage sites of the Yahu municipal solid waste landfill site in Pingshan District, Shenzhen, China, which shows that there are two leachate leakage passages in the waste landfill dam A between NZK-2 and NZK-3, and between NZK-6 and NZK-7. © The Author(s) 2015.

  3. Enhancing biomethanogenic treatment of fresh incineration leachate using single chambered microbial electrolysis cells.

    Science.gov (United States)

    Gao, Yan; Sun, Dezhi; Dang, Yan; Lei, Yuqing; Ji, Jiayang; Lv, Tingwei; Bian, Rui; Xiao, Zhihui; Yan, Liangming; Holmes, Dawn E

    2017-05-01

    Methanogenic treatment of municipal solid waste (MSW) incineration leachate can be hindered by high concentrations of refractory organic matter and humification of compounds in the leachate. In an attempt to overcome some of these impediments, microbial electrolysis cells (MECs) were incorporated into anaerobic digesters (ADMECs). COD removal efficiencies and methane production were 8.7% and 44.3% higher in ADMECs than in controls, and ADMEC reactors recovered more readily from souring caused by high organic loading rates. The degradation rate of large macromolecules was substantially higher (96% vs 81%) in ADMEC than control effluent, suggesting that MECs stimulated degradation of refractory organic matter and reduced humification. Exoelectrogenic bacteria and microorganisms known to form syntrophic partnerships were enriched in ADMECs. These results show that ADMECs were more effective at treatment of MSW incineration leachate, and should be taken into consideration when designing future treatment facilities. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Performance evaluation of startup for a yeast membrane bioreactor (MBRy) treating landfill leachate.

    Science.gov (United States)

    Amaral, Míriam C S; Gomes, Rosimeire F; Brasil, Yara L; Oliveira, Sílvia M A; Moravia, Wagner G

    2017-12-06

    The startup process of a membrane bioreactor inoculated with yeast biomass (Saccharomyces cerevisiae) and used in the treatment of landfill leachate was evaluated. The yeast membrane bioreactor (MBRy) was inoculated with an exogenous inoculum, a granulated active dry commercial bakers' yeast. The MBRy was successfully started up with a progressive increase in the landfill leachate percentage in the MBRy feed and the use of Sabouraud Dextrose Broth. The membrane plays an important role in the startup phase because of its full biomass retention and removal of organic matter. MBRy is a suitable and promising process to treat recalcitrant landfill leachate. After the acclimation period, the COD and NH 3 removal efficiency reached values of 72 ± 3% and 39 ± 2% respectively. MBRy shows a low membrane-fouling potential. The membrane fouling was influenced by soluble microbial products, extracellular polymeric substances, sludge particle size, and colloidal dissolved organic carbon.

  5. Analysis of Electro-Oxidation Suitability for Landfill Leachate Treatment through an Experimental Study

    Directory of Open Access Journals (Sweden)

    Marco Ragazzi

    2013-09-01

    Full Text Available This paper examines the efficiency of electro-oxidation used as the single pretreatment of landfill leachate. The experiments were performed on three different types of leachate. The results obtained using this electrochemical method results were analyzed after seven days of treatment. The main characteristics of leachate and a diagram of the experimental apparatus are presented. The overall objectives were to contribute to the knowledge of electrochemical treatments for the reduction of COD, BOD5, ammonium, and total suspended solids, and also to examine whether there was any resulting hexavalent chromium in the liquid sample. The yields obtained were considered satisfactory, particularly given the simplicity of this technology. Like all processes used to treat refluent water, the applicability of this technique to a specific industrial refluent needs to be supported by feasibility studies to estimate its effectiveness and optimize the project parameters. This could be a future development of the work.

  6. Assessment of the Spatial Variability in Leachate Migration from an Old Landfill Site

    DEFF Research Database (Denmark)

    Kjeldsen, Peter; Bjerg, Poul Løgstrup; Winther, Pia

    1995-01-01

    Investigations of the pollution of groundwater from old landfills have in most cases focused on delineating the pollution plume and only in very few cases on the landfill as a source to groundwater pollution. Landfills often cover large areas. Spatial variations in leachate composition may have...... great impact on the location of the main pollution plume in the downstream aquifer. Grindsted landfill in Denmark was investigated by sampling leachate beneath the landfill and in groundwater at the borders of the landfill. A pronounced variability in leachate quality and leakage patterns from...... the landfill was observed. Also variations in local groundwater flow directions were found. These observations are very important for delineation of the groundwater pollution and for proper choice of remedial action activities, related both to the plume and to the landfill....

  7. Constructed wetlands for municipal solid waste landfill leachate treatment. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Peverly, J.; Sanford, W.E.; Steenhuis, T.S. [Cornell Univ., Ithaca, NY (United States)

    1993-11-01

    In 1989, the US Geological Survey and Cornell University, in cooperation with the New York State Energy Research and Development Authority and the Tompkins County Solid Waste Department, began a three-year study at a municipal solid-waste landfill near Ithaca, New York, to test the effectiveness of leachate treatment with constructed wetlands and to examine the associated treatment processes. Specific objectives of the study were to examine: treatment efficiency as function of substrate composition and grain size, degree of plant growth, and seasonal changes in evapotranspiration rates and microbial activity; effects of leachate and plant growth on the hydraulic characteristics of the substrate; and chemical, biological, and physical processes by which nutrients, metals, and organic compounds are removed from leachate as it flows through the substrate. A parallel study at a municipal solid-waste landfill near Fenton, New York was conducted by researchers at Cornell University, Ithaca College, and Hawk Engineering (Trautmann and others, 1989). Results are described.

  8. The Global Color of Pluto from New Horizons

    Science.gov (United States)

    Olkin, Catherine B.; Spencer, John R.; Grundy, William M.; Parker, Alex H.; Beyer, Ross A.; Schenk, Paul M.; Howett, Carly J. A.; Stern, S. Alan; Reuter, Dennis C.; Weaver, Harold A.; Young, Leslie A.; Ennico, Kimberly; Binzel, Richard P.; Buie, Marc W.; Cook, Jason C.; Cruikshank, Dale P.; Dalle Ore, Cristina M.; Earle, Alissa M.; Jennings, Donald E.; Singer, Kelsi N.; Linscott, Ivan E.; Lunsford, Allen W.; Protopapa, Silvia; Schmitt, Bernard; Weigle, Eddie; the New Horizons Science Team

    2017-12-01

    The New Horizons flyby provided the first high-resolution color maps of Pluto. We present here, for the first time, an analysis of the color of the entire sunlit surface of Pluto and the first quantitative analysis of color and elevation on the encounter hemisphere. These maps show the color variation across the surface from the very red terrain in the equatorial region, to the more neutral colors of the volatile ices in Sputnik Planitia, the blue terrain of East Tombaugh Regio, and the yellow hue on Pluto’s North Pole. There are two distinct color mixing lines in the color-color diagrams derived from images of Pluto. Both mixing lines have an apparent starting point in common: the relatively neutral-color volatile-ice covered terrain. One line extends to the dark red terrain exemplified by Cthulhu Regio and the other extends to the yellow hue in the northern latitudes. There is a latitudinal dependence of the predominant color mixing line with the most red terrain located near the equator, less red distributed at mid-latitudes and more neutral terrain at the North Pole. This is consistent with the seasonal cycle controlling the distribution of colors on Pluto. Additionally, the red color is consistent with tholins. The yellow terrain (in the false color images) located at the northern latitudes occurs at higher elevations.

  9. Over-the-horizon radar research consortium formed

    Science.gov (United States)

    One casualty of shrinking military budgets and the disappearance of Cold War threats has been the U.S. Air Force's over-the-horizon or ionospheric radar system known as OTH-B. For the scientific community this is not all bad news: The vast potential of the six powerful 5-28-MHz radars for geophysical monitoring may soon be available to anyone who can afford to run and maintain them.To reap civilian benefits from the billiondollar investment in these radars, the 1994 defense appropriation directed the Air Force to “fully cooperate with efforts of other governmental agencies to utilize the dual-use capabilities of this system for remote environmental and weather monitoring and other purposes.” So far, only the National Oceanic and Atmospheric Administration (NOAA) has tapped the radars' environmental monitoring potential. Since 1991, it has conducted tests to map surface wind direction over basin-scale ocean areas and track ocean storms, including Hurricane Andrew. Recent tests show the radar can be used to map ocean surface currents as well.

  10. Stochastic PDEs and Infinite Horizon Backward Doubly Stochastic Differential Equations

    Directory of Open Access Journals (Sweden)

    Bo Zhu

    2012-01-01

    Full Text Available We give a sufficient condition on the coefficients of a class of infinite horizon BDSDEs, under which the infinite horizon BDSDEs have a unique solution for any given square integrable terminal values. We also show continuous dependence theorem and convergence theorem for this kind of equations. A probabilistic interpretation for solutions to a class of stochastic partial differential equations is given.

  11. The NMC Horizon Report: 2013 Higher Education Edition

    Science.gov (United States)

    Johnson, L.; Adams Becker, S.; Cummins, M.; Estrada, V.; Freeman, A.; Ludgate, H.

    2013-01-01

    The internationally recognized "NMC Horizon Report" series and regional "NMC Technology Outlooks" are part of the NMC Horizon Project, a comprehensive research venture established in 2002 that identifies and describes emerging technologies likely to have a large impact over the coming five years in education around the globe.…

  12. Investigation of landfill leachate toxic potency: An integrated approach with the use of stress indices in tissues of mussels

    Energy Technology Data Exchange (ETDEWEB)

    Tsarpali, Vasiliki [Section of Animal Biology, Department of Biology, Faculty of Sciences, University of Patras, 26500 Patras (Greece); Dailianis, Stefanos, E-mail: sdailianis@upatras.gr [Section of Animal Biology, Department of Biology, Faculty of Sciences, University of Patras, 26500 Patras (Greece)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer Leachate induces mortality of mussels and their cell death at very low doses. Black-Right-Pointing-Pointer Prepathological alterations occur in tissues of leachate-exposed mussels. Black-Right-Pointing-Pointer Alterations of stress indices reveal neurotoxic and genotoxic potency of leachate. Black-Right-Pointing-Pointer Leachate could induce oxidative damage in tissues of leachate-exposed mussels. - Abstract: The present study investigates the harmful impacts of landfill leachate release and/or disposal into the marine environment, as well as its ability to induce lethal and pre-pathological alterations in marine organisms, such as the mussel Mytilus galloprovincialis. In specific, mortality test (96 h), performed first in order to estimate leachate lethal endpoints, showed increased levels of mussel mortality after exposure to leachate higher than 0.5%, v/v (96 h LC{sub 50} = 0.526%, v/v), while the exposure to 0.01 and 0.1% (v/v) of leachate showed negligible levels of mortality (96 h LC{sub 10} = 0.167%, v/v). Furthermore, the estimation of lysosomal membrane integrity in hemocytes of exposed mussels (Neutral Red Retention Time assay) showed increased levels of lysosomal destabilization in cells of mussels exposed to sub-lethal concentrations of leachate (0.01, 0.1 and 0.5%, v/v) for 4 days. In order to exclude parameters, such as mussel mortality and cell death, which could interfere with the obtained results, leachate at final concentrations of 0.01 and 0.1% (v/v) were finally used for the estimation of a battery of stress indices in target tissues of mussels, such as hemolymph, gills and digestive gland. According to the results, leachate-exposed mussels showed a significant inhibition of acetylcholinesterase activity, increased levels of nuclear abnormalities, as well as increased levels of metallothionein, superoxide anion and lipid peroxides (in terms of malondialdehyde equivalents) in each tissue tested. The

  13. Leaf-litter leachate concentration promotes heterotrophy in freshwater biofilms: Understanding consequences of water scarcity.

    Science.gov (United States)

    Martínez, Aingeru; Kominoski, John Stephen; Larrañaga, Aitor

    2017-12-01

    Climate change is increasing overall temporal variability in precipitation resulting in a seasonal water availability, both increasing periods of flooding and water scarcity. During low water availability periods, the concentration of leachates from riparian vegetation increases, subsequently increasing dissolved organic matter (DOM). Moreover, shifts in riparian vegetation by land use changes impact the quantity and quality of DOM. Our objective was to test effects of increasing DOM concentrations from Eucalyptus grandis (one of the most cultivated tree species in the world) leachates on the metabolism (respiration, R; gross primary productivity, GPP) and extracellular enzyme activities (EEAs) of freshwater biofilms. To test effects of DOM concentrations on freshwater biofilm functions, we incubated commercial cellulose sponges in a freshwater pond to allow biofilm colonization, and then exposed biofilms to five different concentrations of leaf-litter leachates of E. grandis for five days. To test if responses to DOM concentrations varied with colonization stage of biofilms, we measured treatment effects on biofilms colonizing standard substrates after one, two, three and four weeks of colonization. Increases in leachates concentrations enhanced biofilm heterotrophy, increasing R rates and decreasing GPP. Leachate concentrations did not affect biofilm EEAs, and changes in biofilm metabolism were not explained by treatment-induced changes in biofilm biomass or stoichiometry. We detected the lowest production:respiration ratios, i.e. more heterotrophic assemblages, with the most concentrated leachate solution and the most advanced biofilm colonization stages. Shifts in quantity of dissolved organic matter in freshwaters may further influence ecosystem metabolism and carbon processing. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. The Study of LeachateTreatment by Using Three Advanced Oxidation Process Based Wet air Oxidation

    Directory of Open Access Journals (Sweden)

    Behroz Karimi

    2013-01-01

    Full Text Available Wet air oxidation is regarded as appropriate options for wastewater treatment with average organic compounds. The general purpose of this research is to determine the efficiency of three wet air oxidation methods, wet oxidation with hydrogen peroxide and absorption with activated carbon in removing organic matter and nitrogenous compounds from Isfahan's urban leachate. A leachate sample with the volume of 1.5 liters entered into a steel reactor with the volume of three liters and was put under a 10-bar pressure, at temperatures of 100, 200, and 300[degree sign] as well as three retention times of 30, 60, and 90 minutes. The sample was placed at 18 stages of leachate storage ponds in Isfahan Compost Plant with the volume of 20 liters, using three WPO, WAO methods and a combination of WAO/GAC for leachate pre-treatment. Thirty percent of pure oxygen and hydrogen peroxide were applied as oxidation agents. The COD removal efficiency in WAO method is 7.8-33.3%, in BOD is 14.7-50.6%, the maximum removal percentage (efficiency for NH4-N is 53.3% and for NO3-N is 56.4-73.9%. The removal efficiency of COD and BOD5 is 4.6%-34 and 24%-50 respectively in WPO method. Adding GAC to the reactor, the removal efficiency of all parameters was improved. The maximum removal efficiency was increased 48% for COD, 31%-43.6 for BOD5 by a combinational method, and the ratio of BOD5/COD was also increased to 90%. In this paper, WAO and WPO process was used for Leachate pre-treatment and WAO/GAC combinational process was applied for improving the organic matter removal and leachate treatment; it was also determined that the recent process is much more efficient in removing resistant organic matter.

  15. Energy consumption by forward osmosis treatment of landfill leachate for water recovery.

    Science.gov (United States)

    Iskander, Syeed Md; Zou, Shiqiang; Brazil, Brian; Novak, John T; He, Zhen

    2017-05-01

    Forward osmosis (FO) is an alternative approach for treating landfill leachate with potential advantages of reducing leachate volume and recovering high quality water for direct discharge or reuse. However, energy consumption by FO treatment of leachate has not been examined before. Herein, the operational factors such as recirculation rates and draw concentrations were studied for their effects on the quantified energy consumption by an FO system treating actual leachate collected from two different landfills. It was found that the energy consumption increased with a higher recirculation rate and decreased with a higher draw concentration, and higher water recovery tended to reduce energy consumption. The highest energy consumption was 0.276±0.033kWhm -3 with the recirculation rate of 110mLmin -1 and 1-M draw concentration, while the lowest of 0.005±0.000kWhm -3 was obtained with 30mLmin -1 recirculation and 3-M draw concentration. The leachate with lower concentrations of the contaminants had a much lower requirement for energy, benefited from its higher water recovery. Osmotic backwashing appeared to be more effective for removing foulants, but precise understanding of membrane fouling and its controlling methods will need a long-term study. The results of this work have implied that FO treatment of leachate could be energy efficient, especially with the use of a suitable draw solute that can be regenerated in an energy efficient way and/or through combination with other treatment technologies that can reduce contaminant concentrations before FO treatment, which warrants further investigation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Quantitation of transgenic plant DNA in leachate water: real-time polymerase chain reaction analysis.

    Science.gov (United States)

    Gulden, Robert H; Lerat, Sylvain; Hart, Miranda M; Powell, Jeff R; Trevors, Jack T; Pauls, K Peter; Klironomos, John N; Swanton, Clarence J

    2005-07-27

    Roundup Ready (RR) genetically modified (GM) corn and soybean comprise a large portion of the annual planted acreage of GM crops. Plant growth and subsequent plant decomposition introduce the recombinant DNA (rDNA) into the soil environment, where its fate has not been completely researched. Little is known of the temporal and spatial distribution of plant-derived rDNA in the soil environment and in situ transport of plant DNA by leachate water has not been studied before. The objectives of this study were to determine whether sufficient quantities of plant rDNA were released by roots during growth and early decomposition to be detected in water collected after percolating through a soil profile and to determine the influence of temperature on DNA persistence in the leachate water. Individual plants of RR corn and RR soybean were grown in modified cylinders in a growth room, and the cylinders were flushed with rain water weekly. Immediately after collection, the leachate was subjected to DNA purification followed by rDNA quantification using real-time Polymerase Chain Reaction (PCR) analysis. To test the effects of temperature on plant DNA persistence in leachate water, water samples were spiked with known quantities of RR soybean or RR corn genomic DNA and DNA persistence was examined at 5, 15, and 25 degrees C. Differences in the amounts and temporal distributions of root-derived rDNA were observed between corn and soybean plants. The results suggest that rainfall events may distribute plant DNA throughout the soil and into leachate water. Half-lives of plant DNA in leachate water ranged from 1.2 to 26.7 h, and persistence was greater at colder temperatures (5 and 15 degrees C).

  17. [Litter decomposition of dominant plantations in Guangxi and its effects on leachate quality].

    Science.gov (United States)

    Yang, Gai-Ren; Zhang, Xiu-Qing; Cai, De-Suo; Shi, Xian-Hui; Zhang, Hua; Huang, Cheng-Biao

    2012-01-01

    To understand the decomposition characteristics of the litters in different forest plantations and the effects of released substances during litter decomposition on the leachate quality, litter samples (leaf, shoot, and cortices) were collected from five forest plantations (1 year-old Eucalyptus urophylla x E. grandis, EU1; 4 year-old Eucalyptus urophylla x E. grandis, EU4; 7 year-old Acacia mangium x A. auriculaef, AM; 13 year-old Pinus massoniana Lamb, PL; and mixed broad-leaved softwood, BL), and incubated at 28 degrees C, using water leached for 255 days. In the first 105 days, the litter leachates of EU1 and EU4 had significantly higher coloration and N and P contents and lower pH than those of AM, PL, and BL. On the 255th day, the cumulative chemical oxygen demand (COD) in the leaf litters leachates of EU1 and EU4 was 193.9 and 212.8 g x kg(-1), being 4.2, 4.0, and 4.3 times and 5.3, 4.4, and 4.7 times higher than that of AM, PL, and BL, respectively. The mass loss rate and the N and P leaching rate of the leaf litter of EU1 were significantly higher than those of AM, PL, and BL. The mass loss rate of cortices of EU1 was significantly higher than that of PL. No significant difference was observed for the leaching rate of the shoot litters between AM, PL, and BL. Among the litter samples, leaf litter was easiest to be decomposed, while shoot litter was most difficult to be decomposed. The pH value of the litter leachates of Eucalyptus plantations was significantly negatively correlated with leachate chroma and COD, and the COD had significant positive correlations with the concentrations of total N and P in the leachates.

  18. Abiotic properties of landfill leachate controlling arsenic release from drinking water adsorbents.

    Science.gov (United States)

    Stuckman, Mengling Y; Lenhart, John J; Walker, Harold W

    2011-10-15

    In this study, As leaching from five arsenic bearing solid residuals (ABSRs) comprised of the iron hydroxide adsorbent Bayoxide E33 used in long-term operations was evaluated in leaching trials using California Waste Extraction Test (CalWET) and Toxicity Characteristic Leaching Protocol (TCLP) leachate solutions, a landfill leachate (LL), and synthetic leachate (SL). The initial As loading of the media, which reflects the influence of source water chemistry and varying treatment conditions at the point of removal, strongly influenced the magnitude of As release. The chemical composition of the leachate also influenced As release and demonstrated the relative importance of different release mechanisms, namely media dissolution, pH-dependent sorption/desorption, and ion exchange. The CalWET solution, which partially dissolved the iron-based media, resulted in 100 times more As release than did the TCLP solution, which did not dissolve the media. The LL had a higher pH than the TCLP solution, and even though its organic carbon content was lower it tended to release more As. Tests with the SL were conducted to determine the influence of variations in leachate pH, phosphate, bicarbonate, sulfate, silicate, and natural organic matter (NOM). Release increased at high pH, in the presence of high concentrations of phosphate and bicarbonate, and in the presence of high NOM concentrations. For pH, this reflects the pH-dependence of sorption reactions, whereas for the anions and NOM, direct competition appeared important. Similar to the CalWET solution, excess NOM dissolved portions of the media thereby facilitating As release. In general, our results suggest that estimating As release into landfills will remain a challenge as it depends upon As loading, which reflects site-specific properties, and the composition of the leachate, which varies from landfill to landfill. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Leachate generation from landfill in a semi-arid climate: A qualitative and quantitative study from Sousse, Tunisia.

    Science.gov (United States)

    Frikha, Youssef; Fellner, Johann; Zairi, Moncef

    2017-09-01

    Despite initiatives for enhanced recycling and waste utilization, landfill still represents the dominant disposal path for municipal solid waste (MSW). The environmental impacts of landfills depend on several factors, including waste composition, technical barriers, landfill operation and climatic conditions. A profound evaluation of all factors and their impact is necessary in order to evaluate the environmental hazards emanating from landfills. The present paper investigates a sanitary landfill located in a semi-arid climate (Tunisia) and highlights major differences in quantitative and qualitative leachate characteristics compared to landfills situated in moderate climates. Besides the qualitative analysis of leachate samples, a quantitative analysis including the simulation of leachate generation (using the HELP model) has been conducted. The results of the analysis indicate a high load of salts (Cl, Na, inorganic nitrogen) in the leachate compared to other landfills. Furthermore the simulations with HELP model highlight that a major part of the leachate generated originates form the water content of waste.

  20. Observations of the Geometry of Horizon-Based Optical Navigation

    Science.gov (United States)

    Christian, John; Robinson, Shane

    2016-01-01

    NASA's Orion Project has sparked a renewed interest in horizon-based optical navigation(OPNAV) techniques for spacecraft in the Earth-Moon system. Some approaches have begun to explore the geometry of horizon-based OPNAV and exploit the fact that it is a conic section problem. Therefore, the present paper focuses more deeply on understanding and leveraging the various geometric interpretations of horizon-based OPNAV. These results provide valuable insight into the fundamental workings of OPNAV solution methods, their convergence properties, and associated estimate covariance. Most importantly, the geometry and transformations uncovered in this paper lead to a simple and non-iterative solution to the generic horizon-based OPNAV problem. This represents a significant theoretical advancement over existing methods. Thus, we find that a clear understanding of geometric relationships is central to the prudent design, use, and operation of horizon-based OPNAV techniques.

  1. Cosmological horizons as new examples of the membrane paradigm

    International Nuclear Information System (INIS)

    Wang, Tower

    2015-01-01

    In this paper we aim to provide new examples of the application and the generality of the membrane paradigm. The membrane paradigm is a formalism for studying the event horizon of black holes. After analyzing it with some technical details and realizing it in the Reissner–Nordström black hole, we apply the paradigm to cosmological horizons, first to the pure de Sitter horizon, and then to the trapping horizon of the Friedmann–Lemaître–Robertson–Walker Universe. In the latter case, the cosmological stretched horizon is oblique, thus the running of the renormalization parameter is nonzero in the timelike direction and gives a correction to the membrane pressure. In this paradigm, the cosmological equations come from continuity equations of the membrane fluid and the bulk fluid respectively. (paper)

  2. Quantification of regional leachate variance from municipal solid waste landfills in China

    DEFF Research Database (Denmark)

    Yang, Na; Damgaard, Anders; Kjeldsen, Peter

    2015-01-01

    contents. To overcome this problem, a new estimation method was established considering two sources: (1) precipitation infiltrated throughout waste layers, which was simulated with the HELP model, (2) water squeezed out of the waste itself, which was theoretically calculated using actual data of Chinese...... of about 58.2%. In China-NW, accumulated leachate amounts were very low and mainly the result of waste degradation, implying on-site spraying/irrigation or recirculation may be an economic approach to treatment. In China-N, water squeezed out of waste by compaction totaled 22-45% of overall leachate...

  3. A method for determination of cadmium species in solid waste leachates

    DEFF Research Database (Denmark)

    Christensen, Thomas H.; Xu Ze Lun

    1989-01-01

    A procedure has been developed for determination of cadmium (Cd) species in solid waste leachates employing a cation exchange resin (Chelex 100) in a batch-column-batch sequence. The procedure allows for determination of free divalent Cd (Cd2+), labile Cd complexes, slowly labile Cd complexes...... and stable Cd complexes. The effects of equilibration time, pH, calcium activity and ratio of sample volume to amount of resin have been examined. The method has been tested on standardized chloride and EDTA solutions containing Cd and on two actual leachates. The Cd species determined in the chloride...

  4. Effects of tire leachate on the invasive mosquito Aedes albopictus and the native congener Aedes triseriatus

    Directory of Open Access Journals (Sweden)

    Oswaldo C. Villena

    2017-09-01

    Full Text Available Discarded vehicle tire casings are an important artificial habitat for the developmental stages of numerous vector mosquitoes. Discarded vehicle tires degrade under ultraviolet light and leach numerous soluble metals (e.g., barium, cadmium, zinc and organic substances (e.g., benzothiazole and its derivatives [BZTs], polyaromatic hydrocarbons [PAHs] that could affect mosquito larvae that inhabit the tire casing. This study examined the relationship between soluble zinc, a common marker of tire leachate, on mosquito densities in tire habitats in the field, and tested the effects of tire leachate on the survival and development of newly hatched Aedes albopictus and Aedes triseriatus larvae in a controlled laboratory dose-response experiment. In the field, zinc concentrations were as high as 7.26 mg/L in a single tire and averaged as high as 2.39 (SE ± 1.17 mg/L among tires at a single site. Aedes albopictus (37/42 tires, 81.1% and A. triseriatus (23/42, 54.8% were the most widespread mosquito species, co-occurred in over half (22/42, 52.4% of all tires, and A. triseriatus was only collected without A. albopictus in one tire. Aedes triseriatus was more strongly negatively associated with zinc concentration than A. albopictus, and another common mosquito, C. pipiens, which was found in 17 tires. In the laboratory experiment, A. albopictus per capita rate of population change (λ′ was over 1.0, indicating positive population growth, from 0–8.9 mg/L zinc concentration (0–10,000 mg/L tire leachate, but steeply declined to zero from 44.50–89.00 mg/L zinc (50,000–100,000 mg/L tire leachate. In contrast, A. triseriatus λ′ declined at the lower concentration of 0.05 mg/L zinc (100 mg/L tire leachate, and was zero at 0.45, 8.90, 44.50, and 89.00 mg/L zinc (500, 10,000, 50,000 and 100,000 mg/L tire leachate. These results indicate that tire leachate can have severe negative effects on populations of container-utilizing mosquitoes at

  5. An anaerobic field injection experiment in a landfill leachate plume (Grindsted, Denmark)

    DEFF Research Database (Denmark)

    Albrechtsen, Hans-Jørgen; Bjerg, Poul Løgstrup; Ludvigsen, L.

    1999-01-01

    Redox conditions may be environmental factors which affect the fate of the xenobiotic organic compounds. Therefore the redox conditions were characterized in an anaerobic, leachate-contaminated aquifer 15–60 m downgradient from the Grindsted Landfill, Denmark, where an field injection experiment ...... electron acceptor in the region of the aquifer, which was investigated. Because of the complexity of a landfill leachate plume, several redox processes may occur simultaneously, and an array of methods must be applied for redox characterization in such multicomponent systems....

  6. Mercury concentrations and distribution in soil, water, mine waste leachates, and air in and around mercury mines in the Big Bend region, Texas, USA.

    Science.gov (United States)

    Gray, John E; Theodorakos, Peter M; Fey, David L; Krabbenhoft, David P

    2015-02-01

    Samples of soil, water, mine waste leachates, soil gas, and air were collected from areas mined for mercury (Hg) and baseline sites in the Big Bend area, Texas, to evaluate potential Hg contamination in the region. Soil samples collected within 300 m of an inactive Hg mine contained elevated Hg concentrations (3.8-11 µg/g), which were considerably higher than Hg in soil collected from baseline sites (0.03-0.05 µg/g) distal (as much as 24 km) from mines. Only three soil samples collected within 300 m of the mine exceeded the probable effect concentration for Hg of 1.06 µg/g, above which harmful effects are likely to be observed in sediment-dwelling organisms. Concentrations of Hg in mine water runoff (7.9-14 ng/L) were generally higher than those found in springs and wells (0.05-3.1 ng/L), baseline streams (1.1-9.7 ng/L), and sources of drinking water (0.63-9.1 ng/L) collected in the Big Bend region. Concentrations of Hg in all water samples collected in this study were considerably below the 2,000 ng/L drinking water Hg guideline and the 770 ng/L guideline recommended by the U.S. Environmental Protection Agency (USEPA) to protect aquatic wildlife from chronic effects of Hg. Concentrations of Hg in water leachates obtained from leaching of mine wastes varied widely from <0.001 to 760 µg of Hg in leachate/g of sample leached, but only one leachate exceeded the USEPA Hg industrial soil screening level of 31 µg/g. Concentrations of Hg in soil gas collected at mined sites (690-82,000 ng/m(3)) were highly elevated compared to soil gas collected from baseline sites (1.2-77 ng/m(3)). However, air collected from mined areas at a height of 2 m above the ground surface contained concentrations of Hg (4.9-64 ng/m(3)) that were considerably lower than Hg in soil gas from the mined areas. Although concentrations of Hg emitted from mine-contaminated soils and mine wastes were elevated, persistent wind in southwest Texas disperses Hg in the air within a few meters of the

  7. Black Hole Event Horizons and Advection-Dominated Accretion

    Science.gov (United States)

    McClintock, Jeffrey; Mushotzky, Richard F. (Technical Monitor)

    2001-01-01

    thermal energy will disappear through the event horizon, and the object will be very dim. On the other hand, if the central object is a neutron star or any other object with a surface, then the energy will be radiated from the surface, and the object will be bright.

  8. Responsibility for past and future global warming: time horizon and non-linearities in the climate system

    NARCIS (Netherlands)

    Elzen MGJ den; Schaeffer M; Eickhout B; MNV

    2003-01-01

    The Brazilian proposal for sharing the burden of emissions reductions among Annex-I Parties is based on the relative effect of a country's emissions on the global-mean surface-air temperature. This paper presents calculations of these relative effects, analysing the influence of the time horizon of

  9. Chemistry of fly ash and cyclone ash leachate from waste materials and effects of ash leachates on bacterial growth, nitrogen-transformation activity, and metal accumulation.

    Science.gov (United States)

    Takeuchi, Mio; Kawahata, Hodaka; Gupta, Lallan P; Itouga, Misao; Sakakibara, Hitoshi; Ohta, Hidekazu; Komai, Takeshi; Ono, Yoshiro

    2009-06-15

    The effects of waste ash leachates on soil microorganism were evaluated along with a chemical characterization of ash leachates. Thirty fly ash samples and cyclone ash samples obtained from the incineration of municipal solid waste, plastic waste, and construction waste were used. Twenty-one and 22 samples inhibited N transformation activity of soil microorganism and growth of Bacillus subtilis, respectively. On the other hand, 11 and 18 samples stimulated bacterial activity and growth, respectively, at low concentrations. Generally, cyclone ash contained a smaller amount of toxic metals than fly ash. Our results suggest that cyclone ash can be further studied for reuse, perhaps as a soil amendment. Pb was found to be highly accumulated in B. subtilis cells, and should be carefully monitored when waste ash is reused in the environment.

  10. Analysis of Bio-Obtainable Endocrine Disrupting Metals in River Water and Sediment, Sewage Influent/Effluent, Sludge, Leachate, and Concentrated Leachate, in the Irish Midlands Shannon Catchment

    Directory of Open Access Journals (Sweden)

    Antoinette M. Reid

    2009-01-01

    Full Text Available The application of an acid digestion and subsequent solid-phase extraction (SPE procedure were implemented as preliminary treatments prior to quantifying the levels of potentially endocrine disrupting metals (EDMs in a variety of solid and liquid matrices. These included (solid river sediment, leachate sediment and sewage sludge and also (liquid river water, landfill leachate, concentrated leachate, sewage influent, and sewage effluent, sampled in the Irish Midlands. The total concentrations of cobalt (Co, cadmium (Cd, copper (Cu, chromium (Cr, nickel (Ni, lead (Pb, zinc (Zn, and manganese (Mn, after extraction and preconcentration, were determined by atomic absorption spectroscopy (AAS. Mercury (Hg in sediment and sludge was determined using cold-vapour atomic fluorescence spectroscopy (AFS. For sewage sludge maximum values (mg/kgdw of 4700 Ni, 1642 Mn, 100.0 Cd, 3400 Zn, 36.70 Co, 750.0 Pb, 485.8 Cr, and 1003 Cu were determined whilst in leachate sediment, maximum values (mg/kgdw of 32.10 Ni, 815.0 Mn, 32.78 Cd, 230.3 Zn, 26.73 Co, 3525 Pb, 124.9 Cr, and 50.13 Cu were found. Over several months, the data showed elevated levels in sewage influents, effluents, and sludges compared to a battery of adjacent river water samples and corresponding sediments. There was a definite trend for target values for sediments to be exceeded, while intervention values were only exceeded for cadmium. Overall the pattern in terms of concentration was sewage > leachate > river matrices. A nonparametric assessment of the effect of sewage treatment method on median metal levels in sludge revealed statistically significant differences at the 95% level of confidence for Co, Cr, and Hg and at the 90% level of confidence for Cd.

  11. A Note on the Observational Evidence for the Existence of Event Horizons in Astrophysical Black Hole Candidates

    Directory of Open Access Journals (Sweden)

    Cosimo Bambi

    2013-01-01

    Full Text Available Black holes have the peculiar and intriguing property of having an event horizon, a one-way membrane causally separating their internal region from the rest of the Universe. Today, astrophysical observations provide some evidence for the existence of event horizons in astrophysical black hole candidates. In this short paper, I compare the constraint we can infer from the nonobservation of electromagnetic radiation from the putative surface of these objects with the bound coming from the ergoregion instability, pointing out the respective assumptions and limitations.

  12. Spacetimes foliated by nonexpanding and Killing horizons: Higher dimension

    Science.gov (United States)

    Lewandowski, Jerzy; Szereszewski, Adam; Waluk, Piotr

    2016-09-01

    The theory of nonexpanding horizons (NEHs) geometry and the theory of near-horizon geometries (NHGs) are two mathematical relativity frameworks generalizing the black hole theory. From the point of view of the NEHs theory, a NHG is just a very special case of a spacetime containing a NEH of many extra symmetries. It can be obtained as the Horowitz limit of a neighborhood of an arbitrary extremal Killing horizon. An unexpected relation between the two of them was discovered in the study of spacetimes foliated by a family of NEHs. The class of four-dimensional NHG solutions (either vacuum or coupled to a Maxwell field) was found as a family of examples of spacetimes admitting a NEH foliation. In the current paper, we systematically investigate geometries of the NEHs foliating a spacetime for arbitrary matter content and in arbitrary spacetime dimensions. We find that each horizon belonging to the foliation satisfies a condition that may be interpreted as an invitation for a transversal NEH to exist and to admit the structure of an extremal isolated horizon. Assuming the existence of a transversal extremal isolated horizon, we derive all the spacetime metrics satisfying the vacuum Einstein's equations. In this case, the NEHs become bifurcated Killing horizons.

  13. Horizon shells and BMS-like soldering transformations

    Science.gov (United States)

    Blau, Matthias; O'Loughlin, Martin

    2016-03-01

    We revisit the theory of null shells in general relativity, with a particular emphasis on null shells placed at horizons of black holes. We study in detail the considerable freedom that is available in the case that one solders two metrics together across null hypersurfaces (such as Killing horizons) for which the induced metric is invariant under translations along the null generators. In this case the group of soldering transformations turns out to be infinite dimensional, and these solderings create non-trivial horizon shells containing both massless matter and impulsive gravitational wave components. We also rephrase this result in the language of Carrollian symmetry groups. To illustrate this phenomenon we discuss in detail the example of shells on the horizon of the Schwarzschild black hole (with equal interior and exterior mass), uncovering a rich classical structure at the horizon and deriving an explicit expression for the general horizon shell energy-momentum tensor. In the special case of BMS-like soldering supertranslations we find a conserved shell-energy that is strikingly similar to the standard expression for asymptotic BMS supertranslation charges, suggesting a direct relation between the physical properties of these horizon shells and the recently proposed BMS supertranslation hair of a black hole.

  14. Horizon shells and BMS-like soldering transformations

    Energy Technology Data Exchange (ETDEWEB)

    Blau, Matthias [Albert Einstein Center for Fundamental Physics,Institute for Theoretical Physics, University of Bern,Sidlerstrasse 5, 3012 Bern (Switzerland); O’Loughlin, Martin [University of Nova Gorica,Vipavska 13, 5000 Nova Gorica (Slovenia)

    2016-03-07

    We revisit the theory of null shells in general relativity, with a particular emphasis on null shells placed at horizons of black holes. We study in detail the considerable freedom that is available in the case that one solders two metrics together across null hypersurfaces (such as Killing horizons) for which the induced metric is invariant under translations along the null generators. In this case the group of soldering transformations turns out to be infinite dimensional, and these solderings create non-trivial horizon shells containing both massless matter and impulsive gravitational wave components. We also rephrase this result in the language of Carrollian symmetry groups. To illustrate this phenomenon we discuss in detail the example of shells on the horizon of the Schwarzschild black hole (with equal interior and exterior mass), uncovering a rich classical structure at the horizon and deriving an explicit expression for the general horizon shell energy-momentum tensor. In the special case of BMS-like soldering supertranslations we find a conserved shell-energy that is strikingly similar to the standard expression for asymptotic BMS supertranslation charges, suggesting a direct relation between the physical properties of these horizon shells and the recently proposed BMS supertranslation hair of a black hole.

  15. Perturbative string thermodynamics near black hole horizons

    International Nuclear Information System (INIS)

    Mertens, Thomas G.; Verschelde, Henri; Zakharov, Valentin I.

    2015-01-01

    We provide further computations and ideas to the problem of near-Hagedorn string thermodynamics near (uncharged) black hole horizons, building upon our earlier work http://dx.doi.org/10.1007/JHEP03(2014)086. The relevance of long strings to one-loop black hole thermodynamics is emphasized. We then provide an argument in favor of the absence of α ′ -corrections for the (quadratic) heterotic thermal scalar action in Rindler space. We also compute the large k limit of the cigar orbifold partition functions (for both bosonic and type II superstrings) which allows a better comparison between the flat cones and the cigar cones. A discussion is made on the general McClain-Roth-O’Brien-Tan theorem and on the fact that different torus embeddings lead to different aspects of string thermodynamics. The black hole/string correspondence principle for the 2d black hole is discussed in terms of the thermal scalar. Finally, we present an argument to deal with arbitrary higher genus partition functions, suggesting the breakdown of string perturbation theory (in g s ) to compute thermodynamical quantities in black hole spacetimes.

  16. Perturbative string thermodynamics near black hole horizons

    Energy Technology Data Exchange (ETDEWEB)

    Mertens, Thomas G.; Verschelde, Henri [Department of Physics and Astronomy, Ghent University, Krijgslaan, 281-S9, 9000 Gent (Belgium); Zakharov, Valentin I. [ITEP,B. Cheremushkinskaya 25, Moscow, 117218 (Russian Federation); Moscow Institute of Physics & Technology,Dolgoprudny, Moscow Region, 141700 (Russian Federation); School of Biomedicine, Far Eastern Federal University,Sukhanova str. 8, Vladivostok, 690950 (Russian Federation)

    2015-06-24

    We provide further computations and ideas to the problem of near-Hagedorn string thermodynamics near (uncharged) black hole horizons, building upon our earlier work http://dx.doi.org/10.1007/JHEP03(2014)086. The relevance of long strings to one-loop black hole thermodynamics is emphasized. We then provide an argument in favor of the absence of α{sup ′}-corrections for the (quadratic) heterotic thermal scalar action in Rindler space. We also compute the large k limit of the cigar orbifold partition functions (for both bosonic and type II superstrings) which allows a better comparison between the flat cones and the cigar cones. A discussion is made on the general McClain-Roth-O’Brien-Tan theorem and on the fact that different torus embeddings lead to different aspects of string thermodynamics. The black hole/string correspondence principle for the 2d black hole is discussed in terms of the thermal scalar. Finally, we present an argument to deal with arbitrary higher genus partition functions, suggesting the breakdown of string perturbation theory (in g{sub s}) to compute thermodynamical quantities in black hole spacetimes.

  17. Mobilization of iron and arsenic from soil by construction and demolition debris landfill leachate.

    Science.gov (United States)

    Wang, Yu; Sikora, Saraya; Kim, Hwidong; Dubey, Brajesh; Townsend, Timothy

    2012-05-01

    Column experiments were performed to examine (a) the potential for leachate from construction and demolition (C&D) debris landfills to mobilize naturally-occurring iron and arsenic from soils underlying such facilities and (b) the ability of crushed limestone to remove these aqueous phase pollutants. In duplicate columns, water was added to a 30-cm layer of synthetic C&D debris, with the resulting leachate serially passed through a 30-cm soil layer containing iron and arsenic and a 30-cm crushed limestone layer. This experiment was conducted for two different soil types (one high in iron (10,400mg/kg) and the second high in iron (5400mg/kg) and arsenic (70mg/kg)); also monitored were control columns for both soil types with water infiltration alone. Despite low iron concentrations in the simulated C&D debris leachate, elevated iron concentrations were observed when leachate passed through the soils; reductive dissolution was concluded to be the cause of iron mobilization. In the soil containing elevated arsenic, increased iron mobilization from the soil was accompanied by a similar but delayed arsenic mobilization. Since arsenic sorbs to oxidized iron soil minerals, reductive dissolution of these minerals results in arsenic mobilization. Crushed limestone significantly reduced iron (to values below the detection limit of 0.01mg/L in most cases); however, arsenic was not removed to any significant extent. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Treatment of sanitary landfill leachates in degassing gas domes. A low-cost pretreatment process

    Energy Technology Data Exchange (ETDEWEB)

    Rudolph, K.U.

    1987-01-01

    The paper abstracted suggests the purification of leachates from sanitary landfills in packed bed reactors integrated into the landfill. The packed bed reactors of trickling filters will at the same time serve as degassing gabions. Experiences gained in the operation of a pilot plant are discussed in detail. The results obtained prove the procedure to be a feasible, effective and low-cost solution.

  19. Ecotoxicological evaluation of leachate from the Limeira sanitary landfill with a view to identifying acute toxicity

    Directory of Open Access Journals (Sweden)

    José Euclides Stipp Paterniani

    2007-12-01

    Full Text Available Final disposal of solid waste is still a cause for serious impacts on the environment. In sanitary landfills, waste undergoes physical, chemical, and biological decomposition, generating biogas and leachate. Leachate is a highly toxic liquid with a very high pollution potential. The purpose of this work is to evaluate toxicity of in natura leachate samples collected from Limeira Sanitary Landfill, in Limeira, SP. The ecotoxicological evaluation comprised acute toxicity assays using as test organisms Daphnia Similis, seeds of Eruca sativa (arugula, and Allium cepa roots (onion. Analyses of color, pH, turbidity, conductivity, hardness, nitrogen, total organic carbon (TOC, adsorbable organic halogen (AOX, and metals were also carried out. The main results for Eruca sativa (arugula and Allium cepa (onion indicated that the diluted leachate 50% presented similar toxicity to the phenol solution of 1000 mg.L-1 for arugula and 2000 mg.L-1 for onion. With the solution of Cr+6 concentrations of 3000 mg.L-1 for arugula and 2000 mg.L-1 for onion were found. For analyses with Daphnia Similis the EC50 was 9.3% on average. This way it was possible to observe that biological tests are necessary to evaluate the pollution in the effluents or water bodies. These tests serve to determine the toxic potential of a chemical agent or complex mixture.

  20. Effect of substrate-seed mixing and leachate recirculation on solid state digestion of biowaste

    NARCIS (Netherlands)

    Veeken, A.H.M.; Hamelers, H.V.M.

    2000-01-01

    Lab-scale experiments were performed and a mechanistic model was developed to simulate the solid state digestion of biowaste in a batch reactor. Both experiments and model showed that the substrate-seed mixing degree and leachate recirculation rate have a strong effect on the reactor performance.