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Sample records for shredders

  1. Materials recovery from shredder residues

    SciTech Connect

    Daniels, E. J.; Jody, B. J.; Pomykala, J., Jr.

    2000-07-24

    Each year, about five (5) million ton of shredder residues are landfilled in the US. Similar quantities are landfilled in Europe and the Pacific Rim. Landfilling of these residues results in a cost to the existing recycling industry and also represents a loss of material resources that are otherwise recyclable. In this paper, the authors outline the resources recoverable from typical shredder residues and describe technology that they have developed to recover these resources.

  2. Process to recycle shredder residue

    DOEpatents

    Jody, Bassam J.; Daniels, Edward J.; Bonsignore, Patrick V.

    2001-01-01

    A system and process for recycling shredder residue, in which separating any polyurethane foam materials are first separated. Then separate a fines fraction of less than about 1/4 inch leaving a plastics-rich fraction. Thereafter, the plastics rich fraction is sequentially contacted with a series of solvents beginning with one or more of hexane or an alcohol to remove automotive fluids; acetone to remove ABS; one or more of EDC, THF or a ketone having a boiling point of not greater than about 125.degree. C. to remove PVC; and one or more of xylene or toluene to remove polypropylene and polyethylene. The solvents are recovered and recycled.

  3. Recycling of auto shredder residue.

    PubMed

    Nourreddine, Menad

    2007-01-31

    Currently, about 75% of end-of-life vehicle's (ELV) total weight is recycled in EU countries. The remaining 25%, which is called auto shredder residues (ASR) or auto fluff, is disposed of as landfill because of its complexity. It is a major challenge to reduce this percentage of obsolete cars. The European draft directive states that by the year 2006, only 15% of the vehicle's weight can be disposed of at landfill sites and by 2015, this will be reduced to 5%. The draft directive states that a further 10% can be incinerated. The quantities of shredder fluff are likely to increase in the coming years. This is because of the growing number of cars being scrapped, coupled with the increase in the amount of plastics used in cars. In Sweden, some current projects are focusing on recycling of ASR material. In this paper some different alternatives for using this material are reported. The hypothetical injection of ASR into a blast furnace concentrating on ASR's effect to some blast furnace (BF) parameters has been completed using a blast furnace mass balance model. As a result, in principle, ASR can be used as reducing agent in the BF process if certain conditions are met. The particle size of ASR material must be controlled to ensure optimal gasification of the material in the raceway. Regarding the chemical composition of ASR, the non-ferrous content can affect the pig iron quality, which is difficult to rectify at a later point. The most attractive recycling alternative is to use the products obtained from pyrolysis of ASR in appropriate metallurgical processes. PMID:16600493

  4. Automotive shredder residue (ASR) management: An overview.

    PubMed

    Cossu, R; Lai, T

    2015-11-01

    On the basis of statistical data, approximately 6.5 million tons of ELVs were produced in Europe in 2011. ELVs are processed according to a treatment scheme comprising three main phases: depollution, dismantling and shredding. The ferrous fraction represents about 70-75% of the total shredded output, while nonferrous metals represent about 5%. The remaining 20-25% is referred to as automotive shredder residue (ASR). ASR is largely landfilled due to its heterogeneous and complex matrix. With a start date of January 1st 2015, the European Directive 2000/53/EC establishes the reuse and recovery of a minimum of 95% ELV total weight. To reach these targets various post-shredder technologies have been developed with the aim of improving recovery of materials and energy from ASR. In order to evaluate the environmental impacts of different management options of ELVs, the life cycle assessment (LCA) methodology has been applied taking into account the potential implication of sustainable design of vehicles and treatment of residues after shredding of ELVs. Findings obtained reveal that a combination of recycling and energy recovery is required to achieve European targets, with landfilling being viewed as the least preferred option. The aim of this work is to provide a general overview of the recent development of management of ELVs and treatment of ASR with a view to minimizing the amount of residues disposed of in landfill.

  5. Automotive shredder residue (ASR) management: An overview.

    PubMed

    Cossu, R; Lai, T

    2015-11-01

    On the basis of statistical data, approximately 6.5 million tons of ELVs were produced in Europe in 2011. ELVs are processed according to a treatment scheme comprising three main phases: depollution, dismantling and shredding. The ferrous fraction represents about 70-75% of the total shredded output, while nonferrous metals represent about 5%. The remaining 20-25% is referred to as automotive shredder residue (ASR). ASR is largely landfilled due to its heterogeneous and complex matrix. With a start date of January 1st 2015, the European Directive 2000/53/EC establishes the reuse and recovery of a minimum of 95% ELV total weight. To reach these targets various post-shredder technologies have been developed with the aim of improving recovery of materials and energy from ASR. In order to evaluate the environmental impacts of different management options of ELVs, the life cycle assessment (LCA) methodology has been applied taking into account the potential implication of sustainable design of vehicles and treatment of residues after shredding of ELVs. Findings obtained reveal that a combination of recycling and energy recovery is required to achieve European targets, with landfilling being viewed as the least preferred option. The aim of this work is to provide a general overview of the recent development of management of ELVs and treatment of ASR with a view to minimizing the amount of residues disposed of in landfill. PMID:26294011

  6. Recovering recyclable materials from shredder residue

    NASA Astrophysics Data System (ADS)

    Jody, Bassam J.; Daniels, Edward J.; Bonsignore, Patrick V.; Brockmeier, Norman F.

    1994-02-01

    Each year, about 11 million tons of metals are recovered in the United States from about 10 million discarded automobiles. The recovered metals account for about 75 percent of the total weight of the discarded vehicles. The balance of the material, known as shredder residue, amounts to about three million tons annually and is currently landfilled. The residue contains a diversity of potentially recyclable materials, including polyurethane foams, iron oxides, and certain thermoplastics. This article discusses a process under development at Argonne National Laboratory to separate and recover the recyclable materials from this waste stream. The process consists essentially of two stages. First, a physical separation is used to recover the foams and the metal oxides, followed by a chemical process to extract certain thermoplastics. The status of the technology and the process economics are reviewed here.

  7. 77 FR 74006 - Polychlorinated Biphenyls (PCBs); Recycling Plastics From Shredder Residue

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-12

    ... AGENCY Polychlorinated Biphenyls (PCBs); Recycling Plastics From Shredder Residue AGENCY: Environmental... interpretation of its regulations currently under consideration that would generally allow for the recycling of... Recycling Plastics from Shredder Residue, relying principally on the regulatory provisions for excluded...

  8. 78 FR 20640 - Polychlorinated Biphenyls (PCBs); Recycling Plastics from Shredder Residue

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-05

    ... Residue (77 FR 74006). Additional background information on recycling activities that would be affected by... AGENCY Polychlorinated Biphenyls (PCBs); Recycling Plastics from Shredder Residue AGENCY: Environmental... will generally allow for the recycling of plastic separated from shredder residue under the...

  9. Catalytic pyrolysis of automobile shredder residue

    SciTech Connect

    Arzoumanidis, G.G.; McIntosh, M.J.; Steffensen, E.J.

    1995-07-01

    In the United States, approximately 10 million automobiles are scrapped and shredded each year. The mixture of plastics and other materials remaining after recovery of the metals is known as Automobile Shredder Residue (ASR). In 1994, about 3.5 million tons of ASR was produced and disposed of in landfills. However, environmental, legislative, and economic considerations are forcing the industry to search for recycling or other alternatives to disposal. Numerous studies have been done relating the ASR disposal problem to possible recycling treatments such as pyrolysis, gasification, co-liquefaction of ASR with coal, chemical recovery of plastics from ASR, catalytic pyrolysis, reclamation in molten salts, and vacuum pyrolysis. These and other possibilities have been studied intensively, and entire symposia have been devoted to the problem. Product mix, yields, toxicology issues, and projected economics of conceptual plant designs based on experimental results are among the key elements of past studies. Because the kinds of recycling methods that may be developed, along with their ultimate economic value, depend on a very large number of variables, these studies have been open-ended. It is hoped that it may be useful to explore some of these previously studied areas from fresh perspectives. One such approach, currently under development at Argonne National Laboratory, is the catalytic pyrolysis of ASR.

  10. Progress in recycling of automobile shredder residue

    SciTech Connect

    Jody, B.J.; Daniels, E.J.; Pomykala, J.A. Jr.

    1996-03-01

    At Argonne National Laboratory, we have been developing a potentially economical process to recycle automobile shredder residue (ASR). We identified three potentially marketable materials that can be recovered from ASR and developed technologies to recover and upgrade these materials. We build and tested a field-demonstration plant for recycling polyurethane foam and produced about 2000 lb of recycled foam. Several 300-lb samples were sent for evaluation and were found to be of marketable quality. We are also preparing for a large-scale test in which about 200 tons of ASR-derived fines will be used as a raw material in cement making. A major cement company has evaluated small samples of fines prepared in the laboratory and found that they meet its requirements as a substitute for iron ore or mill scale. We also produced about 50 lb of recycled acrylonitrile butadiene styrene (ABS) from obsolete automobiles and found that it has properties that could be readily upgraded to meet the specifications of the automotive industry. In this paper, we briefly discuss the process as a whole and summarize the results obtained from the field work on foam and fines recycling.

  11. Leaching behavior of persistent organic pollutants (POPs) in shredder residues.

    PubMed

    Sakai, S; Urano, S; Takatsuki, H

    1998-01-01

    It is well known that some kinds of waste contain persistent organic pollutants (POPs) such as PCDD/DFs and PCBs. Leaching behaviors of these chemicals, however, have not been focused so much because of their low leachability. On the other hand, shredder residues originated from automobiles and electric appliances consist mainly of plastics, such as PVC, which contain additives including DEHP. In this study, contents analyses and leaching tests with and without surfactant-like substances for shredder residues were conducted. As a result, shredder residues from automobile and electric appliance contained PCBs in ppm level and a quantity of PCDD/DFs. Surfactant-like substances increase the leaching concentration of POPs. DEHP also leached out considerably even though using distilled water. PMID:9828329

  12. 78 FR 5496 - Certain Paper Shredders, Certain Processes for Manufacturing or Relating to Same and Certain...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-25

    ... COMMISSION Certain Paper Shredders, Certain Processes for Manufacturing or Relating to Same and Certain... sale within the United States after importation of certain paper shredders, certain processes for... for importation, and the sale within the United States after importation of certain paper...

  13. Opportunities and Barriers to Resource Recovery and Recycling from Shredder Residue in the United States

    NASA Astrophysics Data System (ADS)

    Nayak, Naren; Apelian, Diran

    2014-11-01

    Shredder residue is the by-product remaining after ferrous and nonferrous metals have been recovered from the processing of vehicles, white goods, and peddler scrap. Shredder residue consists of glass, plastics, rubber, dirt, and small amounts of metal. It is estimated that 5-7 million tons of this shredder residue are landfilled each year in the United States. Technical advancements, coupled with European Union directives and the economic climate, have transformed the recycling of shredder residue in Europe. In the United States, however, regulatory controls and the cheap cost of landfill have worked against the advancement of recycling and recovery of this resource. The Argonne National Laboratory, which is funded by the U.S. Department of Energy, has investigated the effectiveness of recycling shredder residue into polymers. Other research has examined the use of shredder residue in waste-to-energy applications. To improve our ability to process and recycle shredder residue, an investigation of the regulatory, economic, and technological challenges was undertaken. The objective was to conduct a comprehensive review of work done to date, to document the composition of typical shredder output and to identify potential recoverable items (residual metals, plastics, rubber, foam, etc.). Along with uncovering potential new markets, the research would identify the technical, regulatory, and economic barriers to developing those markets.

  14. Automotive shredder residue (ASR) characterization for a valuable management.

    PubMed

    Morselli, Luciano; Santini, Alessandro; Passarini, Fabrizio; Vassura, Ivano

    2010-11-01

    Car fluff is the waste produced after end-of-life-vehicles (ELVs) shredding and metal recovery. It is made of plastics, rubber, glass, textiles and residual metals and it accounts for almost one-third of a vehicle mass. Due to the approaching of Directive 2000/53/EC recycling targets, 85% recycling rate and 95% recovery rate in 2015, the implementation of automotive shredder residue (ASR) sorting and recycling technologies appears strategic. The present work deals with the characterization of the shredder residue coming from an industrial plant, representative of the Italian situation, as for annual fluxes and technologies involved. The aim of this study is to characterize ASR in order to study and develop a cost effective and environmentally sustainable recycling system. Results show that almost half of the residue is made of fines and the remaining part is mainly composed of polymers. Fine fraction is the most contaminated by mineral oils and heavy metals. This fraction produces also up to 40% ashes and its LHV is lower than the plastic-rich one. Foam rubber represents around half of the polymers share in car fluff. Moreover, some chemical-physical parameters exceed the limits of some parameters fixed by law to be considered refuse derived fuel (RDF). As a consequence, ASR needs to be pre-treated in order to follow the energy recovery route.

  15. A chemical approach to recycling mixed plastics from shredder fluff

    SciTech Connect

    Jody, B.J.; Daniels, E.J.; Bonsignore, P.V.

    1991-01-01

    The obsolete automobile is the largest recycled consumer product and the largest source of recycled ferrous scrap. The dismantler recovers mechanical and electrical components from the automobile for resale and sells the hulk to the shredder. The shredder shreds the hulk along with white goods (such as refrigerators, dryers, and washing machines). An air-classification system is used to remove the light fraction, better known as fluff, to facilitate the recovery of the metals downstream. Fluff contains plastics, glass, fibers, and foams, as well as dirt, gravel, sand, and other materials. It also contains automotive fluids and heavy metals, such as lead and cadmium. This paper addresses the treatment and recycling of fluff. In the last decade, several techniques to handle fluff have been proposed and/or investigated, including landfilling, incineration, incineration with heat recovery, incineration with heat recovery and conversion to electricity, gasification, pyrolysis, pelletizing to use fluff as a supplementary fuel, and using fluff to make secondary products (such as lumber board, highway furniture, park benches, and fencing materials). With the exception of landfilling, all of these techniques are driven by the plastics content of fluff.

  16. Recovery of flexible polyurethane foam from shredder residue.

    SciTech Connect

    Daniels, E. J.; Jody, b. J.

    1999-06-29

    Argonne National Laboratory has developed a patented, continuous process for the recovery of flexible polyurethane foam (PUF) from auto shredder residue (ASR). To test the process, Argonne researchers conceived of, designed, and built a continuous foam washing and drying system that was pilot-tested at a shredder facility for six months. Economic analysis of the process, using manufacturers' quotes and operating data from Argonne's pilot plant, indicates a payback of less than two years for a plant producing about 1,000 ton/yr of foam. Samples of clean foam were shipped to three major foam reprocessors; all three indicated that the quality of the PUF recovered by the Argonne process met their requirements. Tests of the recovered foam by an independent testing laboratory showed that the recycled foam met the specifications for several automotive applications, including carpet padding, headliner, and sound-suppression support materials. Recovery of foam reduces the mass and the volume of material going to the landfill by about 5% and 30%, respectively. Annually, recovery will save about 1.2 x 10{sup 12} Btu of energy, cut the amount of solid waste being landfilled by about 150,000 tons, and eliminate the emission of about 250 tons of volatile organic compounds (VOCs) into the air.

  17. Optimized elemental analysis of fluorescence lamp shredder waste.

    PubMed

    Hobohm, Julia; Kuchta, Kerstin; Krüger, Oliver; van Wasen, Sebastian; Adam, Christian

    2016-01-15

    Fluorescence lamps contain considerable amounts of rare earth elements (REE). Several recycling procedures for REE recovery from spent lamps have been established. However, despite their economic importance, the respective recycling is scarce so far, with an REE recovery rate of less than 1%. A reliable analysis of REE and other relevant metals like Yttrium is crucial for a thorough and complete recovery process. This applies both to the solid matter and aqueous phase, since most of the recycling processes include wet-chemical steps. We tested seven different reagent mixtures for microwave-assisted digestion of fluorescent lamp shredder, including hydrofluoric acid, perchloric acid, and hydrogen peroxide. We determined the concentrations of 25 of the most relevant rare earth and other trace elements (Al, P, Ti, V, Cr, Fe, Ni, Cu, Ga, Ge, As, Y, Ag, Cd, Sn, Sb, La, Ce, Eu, Gd, Tb, W, Au, Hg, and Pb) in the respective dilutions. Two independent digestions, one a mixture of perchlorid/nitric/hydrofluoric acid and the other aqua regia, showed the highest concentrations of 23 of these elements, excluding only Sn and Tb. The REE concentrations in the tested lamp shredder sample (stated in g/kg) were 10.2 (Y), 12.1 (La), 7.77 (Ce), 6.91 (Eu), 1.90 (Gd), and 4.11 (Tb). PMID:26592653

  18. Automotive shredder residue (ASR) characterization for a valuable management.

    PubMed

    Morselli, Luciano; Santini, Alessandro; Passarini, Fabrizio; Vassura, Ivano

    2010-11-01

    Car fluff is the waste produced after end-of-life-vehicles (ELVs) shredding and metal recovery. It is made of plastics, rubber, glass, textiles and residual metals and it accounts for almost one-third of a vehicle mass. Due to the approaching of Directive 2000/53/EC recycling targets, 85% recycling rate and 95% recovery rate in 2015, the implementation of automotive shredder residue (ASR) sorting and recycling technologies appears strategic. The present work deals with the characterization of the shredder residue coming from an industrial plant, representative of the Italian situation, as for annual fluxes and technologies involved. The aim of this study is to characterize ASR in order to study and develop a cost effective and environmentally sustainable recycling system. Results show that almost half of the residue is made of fines and the remaining part is mainly composed of polymers. Fine fraction is the most contaminated by mineral oils and heavy metals. This fraction produces also up to 40% ashes and its LHV is lower than the plastic-rich one. Foam rubber represents around half of the polymers share in car fluff. Moreover, some chemical-physical parameters exceed the limits of some parameters fixed by law to be considered refuse derived fuel (RDF). As a consequence, ASR needs to be pre-treated in order to follow the energy recovery route. PMID:20566277

  19. All auto shredding: evaluation of automotive shredder residue generated by shredding only vehicles.

    SciTech Connect

    Duranceau, C. M.; Spangenberger, J. S.

    2011-09-26

    A well developed infrastructure exists for the reuse and recycling of automotive parts and materials. At the end of a vehicle's useful life many parts are removed and sold for reuse and fluids are recovered for recycling or proper disposal. What remains is shredded, along with other metal bearing scrap such as home appliances, demolition debris and process equipment, and the metals are separated out and recycled. The remainder of the vehicle materials is call shredder residue which ends up in the landfill. As energy and natural resources becomes more treasured, increased effort has been afforded to find ways to reduce energy consumption and minimize the use of our limited resources. Many of the materials found in shredder residue could be recovered and help offset the use of energy and material consumption. For example, the energy content of the plastics and rubbers currently landfilled with the shredder residue is equivalent to 16 million barrels of oil per year. However, in the United States, the recovered materials, primarily polymers, cannot be recycled due to current regulatory barriers which preclude the re-introduction into commerce of certain materials because of residual contamination with substances of concern (SOCs) such as polychlorinated biphenyls (PCBs). The source of the PCBs is not well understood. Old transformers, capacitors, white goods and ballasts from lighting fixtures are likely contributing factors. The project was designed to evaluate whether vehicles of varying age and manufacturing origin contribute to the PCB content in shredder residue. Additionally, the project was designed to determine if there are any trends in material composition of the shredder residue from varied age and manufacturing groups. This information would aid in future material recovery facility strategy and design. The test utilized a newly installed shredder plant to shred four categories of automobiles. The categories were defined by vehicle age and the manufacturing

  20. Effect of excluding shredders on leaf litter decomposition in two streams

    SciTech Connect

    Barnes, J.R.; McArthur, J.V.; Cushing, C.E.

    1986-04-30

    The effect of excluding shredders on leaf processing rates was studied in a Rocky Mountain stream in Utah and a cold desert stream in Washington. Experimentally excluding shredders significantly decreased the processing rate in both streams. Processing rates (k) were higher in the desert stream, and it is postulated that this is related to increased microbial activity due to the higher water temperatures. 21 references, 2 tables.

  1. Treatment and recycling of shredder fluff: Final report on Phase 1, Proof of concept

    SciTech Connect

    Jody, B.J.; Daniels, E.J.; Bonsignore, P.V.

    1992-02-01

    This report describes the results of a study conducted by Argonne National Laboratory (ANL) to investigate the feasibility of extracting thermoplastics from shredder fluff for possible recycling. The objective of the research was to evaluate the technical feasibility of using organic solvents to selectively dissolve and recover thermoplastics from the shredder fluff. The basis of the process is physical separation of shredder fluff, which is followed by selective dissolution and recovery of thermoplastics from the plastics-rich stream. In small-scale laboratory runs, four potentially marketable products were recovered by the use of this process: clean polyurethane from (PUF), a mixture of polypropylene (PP) and polyethylene (PE), a mixture of polyvinyl chloride (PVC) and acrylonitrile-butadiene-styrene (ABS), and an iron-rich fine magnetic fraction. Because the residual shredder fluff has been preprocessed, it should be more homogeneous and have a much lower chlorine concentration and moisture content than the raw shredder fluff. These attributes should make the material more economically and environmentally attractive than raw shredder fluff as a fuel or feedstock for the production of fuels and chemicals. A preliminary capital cost estimate of the process was also developed.

  2. Thermal valorisation of automobile shredder residue: injection in blast furnace.

    PubMed

    Mirabile, Daphne; Pistelli, Maria Ilaria; Marchesini, Marina; Falciani, Roberta; Chiappelli, Lisa

    2002-01-01

    Wastes with residual heating value, according to the trend of the world legislation, could be thermally reused. The present study is conducted to verify the possibility of thermal valorisation of a waste, denominated fluff, by injection in blast furnace. The fluff, arising from the automobile shredder operations, is a waste characterised by a high organic matrix and is potentially dangerous due to the heavy metals, oils filter and halogenated plastics content. The first step of the work is the chemical, physical and toxicological characterisation of this material. Then the fluff injection in a blast furnace tuyere is theoretically analysed with a mathematical model. Finally, experimental trials are conducted in a pilot plant, simulating the most important part of the blast furnace: the raceway, in order to analyse process and industrial aspects. In view of an industrial application a first economical evaluation is carried out on the basis of model and experimental results.

  3. Thermal valorisation of automobile shredder residue: injection in blast furnace.

    PubMed

    Mirabile, Daphne; Pistelli, Maria Ilaria; Marchesini, Marina; Falciani, Roberta; Chiappelli, Lisa

    2002-01-01

    Wastes with residual heating value, according to the trend of the world legislation, could be thermally reused. The present study is conducted to verify the possibility of thermal valorisation of a waste, denominated fluff, by injection in blast furnace. The fluff, arising from the automobile shredder operations, is a waste characterised by a high organic matrix and is potentially dangerous due to the heavy metals, oils filter and halogenated plastics content. The first step of the work is the chemical, physical and toxicological characterisation of this material. Then the fluff injection in a blast furnace tuyere is theoretically analysed with a mathematical model. Finally, experimental trials are conducted in a pilot plant, simulating the most important part of the blast furnace: the raceway, in order to analyse process and industrial aspects. In view of an industrial application a first economical evaluation is carried out on the basis of model and experimental results. PMID:12423043

  4. Shredder and incinerator technology for treatment of commercial transuranic wastes

    SciTech Connect

    Oma, K.H.; Westsik, J.H. Jr.; Ross, W.A.

    1985-10-01

    This report describes the selection and evaluation of process equipment to accomplish the shredding and incineration of commercial TRU wastes. The primary conclusions derived from this study are: Shredding and incineration technology appears effective for converting simulated commercial TRU wastes to a noncombustible form. The gas-heated controlled-air incinerator received the highest technical ranking. On a scale of 1 to 10, the incinerator had a Figure-of-Merit (FOM) number of 7.0. This compares to an FOM of 6.1 for the electrically heated controlled-air incinerator and an FOM of 5.8 for the rotary kiln incienrator. The present worth costs of the incineration processes for a postulated commercial reprocessing plant were lowest for the electrically heated and gas-heated controlled-air incinerators with costs of $16.3 M and $16.9 M, respectively (1985 dollars). Due to higher capital and operating costs, the rotary kiln process had a present worth cost of $20.8 M. The recommended process from the three evaluated for the commercial TRU waste application is the gas-heated controlled-air incinerator with a single stage of shredding for feed pretreatment. This process had the best cost-effectiveness ratio of 1.0 (normalized). The electrically heated controller-air incinerator had a rating of 1.2 and the rotary kiln rated a 1.5. Most of the simulated wastes were easily processed by the low-speed shredders evaluated. The HEPA filters proved difficult to process, however. Wood-framed HEPA filters tended to ride on the cutter wheels and spacers without being gripped and shredded. The metal-framed HEPA filters and other difficult to shred items caused the shredders to periodically reach the torque limit and go into an automatic reversal cycle; however, the filters were eventually processed by the units. All three incinerators were ineffective for oxidizing the aluminum metal used as spacers in HEPA filters.

  5. End-of-life vehicle recycling : state of the art of resource recovery from shredder residue.

    SciTech Connect

    Jody, B. J.; Daniels, E. J.; Energy Systems

    2007-03-21

    Each year, more than 50 million vehicles reach the end of their service life throughout the world. More than 95% of these vehicles enter a comprehensive recycling infrastructure that includes auto parts recyclers/dismantlers, remanufacturers, and material recyclers (shredders). Today, about 75% of automotive materials are profitably recycled via (1) parts reuse and parts and components remanufacturing and (2) ultimately by the scrap processing (shredding) industry. The process by which the scrap processors recover metal scrap from automobiles involves shredding the obsolete automobiles, along with other obsolete metal-containing products (such as white goods, industrial scrap, and demolition debris), and recovering the metals from the shredded material. The single largest source of recycled ferrous scrap for the iron and steel industry is obsolete automobiles. The non-metallic fraction that remains after the metals are recovered from the shredded materials (about 25% of the weight of the vehicle)--commonly called shredder residue--is disposed of in landfills. Over the past 10 to 15 years, a significant amount of research and development has been undertaken to enhance the recycle rate of end-of-life vehicles (ELVs), including enhancing dismantling techniques and improving remanufacturing operations. However, most of the effort has focused on developing technology to recover materials, such as polymers, from shredder residue. To make future vehicles more energy efficient, more lighter-weight materials--primarily polymers and polymer composites--will be used in manufacturing these vehicles. These materials increase the percentage of shredder residue that must be disposed of, compared with the percentage of metals. Therefore, as the complexity of automotive materials and systems increases, new technologies will be required to sustain and maximize the ultimate recycling of these materials and systems at end-of-life. Argonne National Laboratory (Argonne), in cooperation

  6. Scarce metals in conventional passenger vehicles and end-of-life vehicle shredder output.

    PubMed

    Widmer, Rolf; Du, Xiaoyue; Haag, Olaf; Restrepo, Eliette; Wäger, Patrick A

    2015-04-01

    Concurrent with the demand for cleaner, lighter, and more efficient vehicles, many scarce metals (SMs) are used in passenger vehicles because of their unique physical and chemical properties. To explore the recycling potential of these metals, it is important to understand their distribution in the vehicles as well as their fate at the vehicles' end-of-life. However, this information remains very scattered and sparse. In this paper, we present a study investigating the distribution of 31 SMs in selected electrical and electronic (EE) components of conventional passenger vehicles and in the end-of-life vehicle shredder fractions from a shredder plant in Switzerland. The results of the chemical analyses show that the mass fractions of Co, Sn, Sr, Ta, Y, and Zr were dominant with >20,000 g/t in the selected EE components and Ag, Ga, Mo, Sb, Sn, Sr, and Zr with >50 g/t in the analyzed shredder fractions. The largest masses of 17 SMs were found in the shredder light fraction, which is incinerated in municipal waste treatment plants mainly in Switzerland; thus, these SMs are currently not recovered. The SM mass fractions in both the EE components and the shredder fractions were projected to their total masses in 100 hypothetical midrange passenger vehicles. The resulting mass balance showed a mismatch of >50% for 23 metals, which indicates other important SM sources such as alloys.

  7. Studies on pyrolysis and gasification of automobile shredder residue in China.

    PubMed

    Ni, Feijian; Chen, Ming

    2014-10-01

    With increasing automobile ownerships in China, the number of end-of-life vehicles has also rapidly increased. However, the automobile shredder residue generated during the dismantling of end-of-life vehicles in China is not treated properly and has caused great resource waste and environmental problems. In this work, automobile shredder residue from a domestic end-of-life vehicles dismantling company was comprehensively studied through element analysis, combustion heat experiment, proximate analysis, and thermogravimetric analysis. The feasibility of using pyrolysis combined with gasification to treat and recycle automobile shredder residue was investigated. The produced gas, oil, and residue yield was measured and the correlation between their yield and the experimental temperature and ratio of air to automobile shredder residue feed was studied. It is found that when ratio of air and experimental temperature are 1.5 mol kg(-1) and 900 °C, respectively, the heat energy of the gas produced per kilogram treated automobile shredder residue reaches a maximum value of 11.28 MJ. The characteristics of pyrolysis oil and solid residue were studied. The solid residue takes up 4.65%~5.57% of the original end-of-life vehicles weight. This greatly helps to reach the target of a 95% recycling rate.

  8. Release and fate of fluorocarbons in a shredder residue landfill cell: 2. Field investigations.

    PubMed

    Scheutz, Charlotte; Fredenslund, Anders M; Nedenskov, Jonas; Kjeldsen, Peter

    2010-11-01

    The shredder residues from automobiles, home appliances and other metal containing products are often disposed in landfills, as recycling technologies for these materials are not common in many countries. Shredder waste contains rigid and soft foams from cushions and insulation panels blown with fluorocarbons. The objective of this study was to determine the gas composition, attenuation, and emission of fluorocarbons in a monofill shredder residue landfill cell by field investigation. Landfill gas generated within the shredder waste primarily consisted of CH(4) (27%) and N(2) (71%), without CO(2), indicating that the gas composition was governed by chemical reactions in combination with anaerobic microbial reactions. The gas generated also contained different fluorocarbons (up to 27 μg L(-1)). The presence of HCFC-21 and HCFC-31 indicated that anaerobic degradation of CFC-11 occurred in the landfill cell, as neither of these compounds has been produced for industrial applications. This study demonstrates that a landfill cell containing shredder waste has a potential for attenuating CFC-11 released from polyurethane (PUR) insulation foam in the cell via aerobic and anaerobic biodegradation processes. In deeper, anaerobic zones of the cell, reductive dechlorination of CFCs to HCFCs was evident, while in the shallow, oxic zones, there was a high potential for biooxidation of both methane and lesser chlorinated fluorocarbons. These findings correlated well with both laboratory results (presented in a companion paper) and surface emission measurements that, with the exception from a few hot spots, indicated that surface emissions were negative or below detection. PMID:20444588

  9. Automobile Shredder Residues in Italy: characterization and valorization opportunities.

    PubMed

    Fiore, S; Ruffino, B; Zanetti, M C

    2012-08-01

    At the moment Automobile Shredder Residue (ASR) is usually landfilled worldwide, but European draft Directive 2000/53/CE forces the development of alternative solutions, stating the 95%-wt recovery of an End of Life Vehicle (ELV) weight to be fulfilled by 2015. This work describes two industrial tests, each involving 250-300 t of ELVs, in which different pre-shredding operations were performed. The produced ASR materials underwent an extended characterization and some post-shredding processes, consisting of dimensional, magnetic, electrostatic and densimetric separation phases, were tested on laboratory scale, having as main purpose the enhancement of ASR recovery/recycling and the minimization of the landfilled fraction. The gathered results show that accurate depollution and dismantling operations are mandatory to obtain a high quality ASR material which may be recycled/recovered and partially landfilled according to the actual European Union regulations, with particular concern for Lower Heating Value (LHV), heavy metals content and Dissolved Organic Carbon (DOC) as critical parameters. Moreover post-shredding technical solutions foreseeing minimum economic and engineering efforts, therefore realizable in common European ELVs shredding plants, may lead to multi-purposed (material recovery and thermal valorization) opportunities for ASR reuse/recovery. PMID:22525092

  10. Production of aggregate from non-metallic automotive shredder residues.

    PubMed

    Rossetti, Vito Alunno; Di Palma, Luca; Medici, Franco

    2006-09-21

    In this paper, the results of an experimentation on the production of granules suitable to be used as aggregates in cementitious or asphalt mixes are presented and discussed. The granules were obtained by granulating the non-metallic fraction of automotive shredder residues. In a preliminary separation step the fluff fraction containing mainly inert and non-metallic materials was sieved and analyzed for the metal content. In the following granulation step, the sieved fraction was mixed with binding materials, fly ash and a densifier agent, to produce granules of 5-30 mm of diameter and up to 1400 kg/m3 of specific weight. The granulation was carried out at room temperature in a rotating tank. Concrete samples prepared using as aggregates the produced granules showed a specific weight up to 1800 kg/m3 and a compressive strength up to about 55% of reference samples prepared using a calcareous aggregate, depending on the fluff content of the mixes, and on the nature of the binder and of the other components used.

  11. Characterization of Shredder Residues generated and deposited in Denmark.

    PubMed

    Ahmed, Nassera; Wenzel, Henrik; Hansen, Jette B

    2014-07-01

    This study presents a detailed characterization of Shredder residues (SR) generated and deposited in Denmark from 1990 to 2010. It represents approximately 85% of total Danish SR. A comprehensive sampling, size fractionation and chemical analysis was carried out on entire samples as well as on each individual size fraction. All significant elemental contents except oxygen were analyzed. The unexplained "balance" was subsequently explained by oxygen content in metal oxides, carbonates, sulphates and in organics, mainly cellulose. Using mass and calorific balance approaches, it was possible to balance the composition and, thereby, estimate the degree of oxidation of elements including metals. This revealed that larger fractions (>10mm, 10-4mm, 4-1mm) contain significant amount of valuable free metals for recovery. The fractionation revealed that the >10mm coarse fraction was the largest amount of SR being 35-40% (w/w) with a metal content constituting about 4-9% of the total SR by weight and the <1mm fine fraction constituted 27-37% (w/w) of the total weight. The lower heat value (LHV) of SR samples over different time periods (1990-2010) was between 7 and 17 MJ/kg, declining with decreasing particle size. The SR composition is greatly dependent on the applied shredding and post shredding processes at the shredding plants causing some variations. There are uncertainties related to sampling and preparation of samples for analyses due to its heterogeneous nature and uncertainties in the chemical analyses results (≈15-25%). This exhaustive characterization is believed to constitute hitherto the best data platform for assessing potential value and feasibility of further resource recovery from SR.

  12. Auto shredder residue recycling: Mechanical separation and pyrolysis

    SciTech Connect

    Santini, Alessandro; Passarini, Fabrizio; Vassura, Ivano; Serrano, David; Dufour, Javier

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer In this work, we exploited mechanical separation and pyrolysis to recycle ASR. Black-Right-Pointing-Pointer Pyrolysis of the floating organic fraction is promising in reaching ELV Directive targets. Black-Right-Pointing-Pointer Zeolite catalyst improve pyrolysis oil and gas yield. - Abstract: sets a goal of 85% material recycling from end-of-life vehicles (ELVs) by the end of 2015. The current ELV recycling rate is around 80%, while the remaining waste is called automotive shredder residue (ASR), or car fluff. In Europe, this is mainly landfilled because it is extremely heterogeneous and often polluted with car fluids. Despite technical difficulties, in the coming years it will be necessary to recover materials from car fluff in order to meet the ELV Directive requirement. This study deals with ASR pretreatment and pyrolysis, and aims to determine whether the ELV material recycling target may be achieved by car fluff mechanical separation followed by pyrolysis with a bench scale reactor. Results show that flotation followed by pyrolysis of the light, organic fraction may be a suitable ASR recycling technique if the oil can be further refined and used as a chemical. Moreover, metals are liberated during thermal cracking and can be easily separated from the pyrolysis char, amounting to roughly 5% in mass. Lastly, pyrolysis can be a good starting point from a 'waste-to-chemicals' perspective, but further research should be done with a focus on oil and gas refining, in order both to make products suitable for the chemical industry and to render the whole recycling process economically feasible.

  13. Pyrolysis and gasification-melting of automobile shredder residue.

    PubMed

    Roh, Seon Ah; Kim, Woo Hyun; Yun, Jin Han; Min, Tae Jin; Kwak, Yeon Ho; Seo, Yong Chil

    2013-10-01

    Automobile shredder residue (ASR) from end-of-life vehicles (ELVs) in Korea has commonly been disposed of in landfills. Due to the growing number of scrapped cars and the decreasing availability of landfill space, effective technology for reducing ASR is needed. However ASR is a complex mixture, and finding an appropriate treatment is not easy on account of the harmful compounds in ASR. Therefore, research continues to seek an effective treatment technology. However most studies have thus far been performed in the laboratory, whereas few commercial and pilot studies have been performed. This paper studies the pyrolysis and gasification-melting of ASR. The pyrolyis characteristics have been analyzed in a thermogravimetric analyzer (TGA), a Lindberg furnace, and a fixed-bed pyrolyzer to study the fundamental characteristics of ASR thermal conversion. As a pilot study, shaft-type gasification-melting was performed. High-temperature gasification-melting was performed in a 5000 kg/day pilot system. The gas yield and syngas (H2 and CO) concentration increase when the reaction temperature increases. Gas with a high calorific value of more than 16,800 kJ/m3 was produced in the pyrolyzer. From the gasification-melting process, syngas of CO (30-40%) and H2(10-15%) was produced, with 5% CH4 produced as well. Slag generation was 17% of the initial ASR, with 5.8% metal content and 4% fly ash. The concentration of CO decreases, whereas the H2, CO2, and CH4 concentrations increase with an increase in the equivalence ratio (ER). The emission levels of dioxin and air pollution compounds except nitrogen oxides (NO(x)) were shown to satisfy Korean regulations.

  14. Pyrolysis and gasification-melting of automobile shredder residue.

    PubMed

    Roh, Seon Ah; Kim, Woo Hyun; Yun, Jin Han; Min, Tae Jin; Kwak, Yeon Ho; Seo, Yong Chil

    2013-10-01

    Automobile shredder residue (ASR) from end-of-life vehicles (ELVs) in Korea has commonly been disposed of in landfills. Due to the growing number of scrapped cars and the decreasing availability of landfill space, effective technology for reducing ASR is needed. However ASR is a complex mixture, and finding an appropriate treatment is not easy on account of the harmful compounds in ASR. Therefore, research continues to seek an effective treatment technology. However most studies have thus far been performed in the laboratory, whereas few commercial and pilot studies have been performed. This paper studies the pyrolysis and gasification-melting of ASR. The pyrolyis characteristics have been analyzed in a thermogravimetric analyzer (TGA), a Lindberg furnace, and a fixed-bed pyrolyzer to study the fundamental characteristics of ASR thermal conversion. As a pilot study, shaft-type gasification-melting was performed. High-temperature gasification-melting was performed in a 5000 kg/day pilot system. The gas yield and syngas (H2 and CO) concentration increase when the reaction temperature increases. Gas with a high calorific value of more than 16,800 kJ/m3 was produced in the pyrolyzer. From the gasification-melting process, syngas of CO (30-40%) and H2(10-15%) was produced, with 5% CH4 produced as well. Slag generation was 17% of the initial ASR, with 5.8% metal content and 4% fly ash. The concentration of CO decreases, whereas the H2, CO2, and CH4 concentrations increase with an increase in the equivalence ratio (ER). The emission levels of dioxin and air pollution compounds except nitrogen oxides (NO(x)) were shown to satisfy Korean regulations. PMID:24282966

  15. Pretreatment of automobile shredder residue (ASR) for fuel utilization.

    PubMed

    Hwang, I H; Yokono, S; Matsuto, T

    2008-03-01

    Automobile shredder residue (ASR) was pretreated to improve its quality for fuel utilization. Composition analysis revealed that ASR components could be classified into four groups: (1) urethane and textile-light fraction and combustibles containing low levels of ash and Cl; (2) plastics and rubber-light or heavy fraction and combustibles containing high levels of Cl; (3) metals and electrical wire-heavy fraction and incombustibles, and (4) particles smaller than 5.6mm with high ash contents. Based on these results, we successively performed sieving to remove particles smaller than 5.6mm, float and sink separations to reject the heavy fraction and plastics and rubber containing Cl, thermal treatment under an inert atmosphere to remove Cl derived from PVC, and char washing to remove soluble chlorides. This series of pretreatments enabled the removal of 78% of the ash and 91% of the Cl from ASR. Sieving using a 5.6-mm mesh removed a considerable amount of ash. Product quality was markedly improved after the float and sink method. Specifically, the sink process using a 1.1 g cm(-3) medium fluid rejected almost all rubber containing Cl and a large amount of PVC. The remaining Cl in char, after heating at 300 degrees C under an inert atmosphere and washing, was considered to be present as insoluble chlorides that volatilized at temperatures above 300 degrees C. Based on a tradeoff relationship between product quality and treatment cost, ASR may be utilized as a form of refuse plastic fuel or char. PMID:18166213

  16. Leaf Degradation, Macroinvertebrate Shredders & Energy Flow in Streams: A Laboratory-Based Exercise Examining Ecosystem Processes

    ERIC Educational Resources Information Center

    Sparkes, Timothy C.; Mills, Colleen M.; Volesky, Lisa; Talkington, Jennifer; Brooke, Joanna

    2008-01-01

    A laboratory-based exercise that demonstrates mechanisms underlying leaf degradation in streams. Students examine the effects of "leaf conditioning" on the feeding behavior of invertebrate shredders. The exercise is completed in two sessions and can be adapted to both high school and college levels.

  17. Failure mechanisms and structural optimization of shredder hammer for metal scraps

    NASA Astrophysics Data System (ADS)

    Zhou, Xianyan; Hu, Zhili; Tao, Yijun; Qin, Xunpeng; Hua, Lin

    2016-06-01

    Recycling retired cars can relieve the environmental pollution and resource waste efficiently. However, a few publications can be found on the failure mechanisms and optimization method of recycling equipment, shredders. Thus, the failure mechanisms and structural optimization of shredder hammers for retired cars are studied aiming improving shredding efficiency and reducing cost. Failure types of shredder hammer are studied theoretically, and it is found that wear failure and fatigue failure are the two main failure types of shredder hammer. The shredding process of metal scraps is analyzed by finite element method, and it can be divided into four stages based on the stress states: initial stage, collision stage, grinding stage and separation stage. It is proved that the shredding efficiency can be improved by increasing cutouts on the hammer head. Finally, it is determined that the hammer with two cutouts is the optimal structure for metal scraps, which can improve the shredding efficiency by 20% and lengthen the hammer life by 15%. This study provides scientific basis for the industry application and theoretical foundation for further research.

  18. Failure mechanisms and structural optimization of shredder hammer for metal scraps

    NASA Astrophysics Data System (ADS)

    Zhou, Xianyan; Hu, Zhili; Tao, Yijun; Qin, Xunpeng; Hua, Lin

    2016-07-01

    Recycling retired cars can relieve the environmental pollution and resource waste efficiently. However, a few publications can be found on the failure mechanisms and optimization method of recycling equipment, shredders. Thus, the failure mechanisms and structural optimization of shredder hammers for retired cars are studied aiming improving shredding efficiency and reducing cost. Failure types of shredder hammer are studied theoretically, and it is found that wear failure and fatigue failure are the two main failure types of shredder hammer. The shredding process of metal scraps is analyzed by finite element method, and it can be divided into four stages based on the stress states: initial stage, collision stage, grinding stage and separation stage. It is proved that the shredding efficiency can be improved by increasing cutouts on the hammer head. Finally, it is determined that the hammer with two cutouts is the optimal structure for metal scraps, which can improve the shredding efficiency by 20% and lengthen the hammer life by 15%. This study provides scientific basis for the industry application and theoretical foundation for further research.

  19. End-of-life vehicle recycling : state of the art of resource recovery from shredder residue.

    SciTech Connect

    Jody, B. J.; Daniels, E. J.; Duranceau, C. M.; Pomykala, J. A.; Spangenberger, J. S.

    2011-02-22

    Each year, more than 25 million vehicles reach the end of their service life throughout the world, and this number is rising rapidly because the number of vehicles on the roads is rapidly increasing. In the United States, more than 95% of the 10-15 million scrapped vehicles annually enter a comprehensive recycling infrastructure that includes auto parts recyclers/dismantlers, remanufacturers, and material recyclers (shredders). Today, over 75% of automotive materials, primarily the metals, are profitably recycled via (1) parts reuse and parts and components remanufacturing and (2) ultimately by the scrap processing (shredding) industry. The process by which the scrap processors recover metal scrap from automobiles involves shredding the obsolete automobile hulks, along with other obsolete metal-containing products (such as white goods, industrial scrap, and demolition debris), and recovering the metals from the shredded material. The single largest source of recycled ferrous scrap for the iron and steel industry is obsolete automobiles. The non-metallic fraction that remains after the metals are recovered from the shredded materials - commonly called shredder residue - constitutes about 25% of the weight of the vehicle, and it is disposed of in landfills. This practice is not environmentally friendly, wastes valuable resources, and may become uneconomical. Therefore, it is not sustainable. Over the past 15-20 years, a significant amount of research and development has been undertaken to enhance the recycle rate of end-of-life vehicles, including enhancing dismantling techniques and improving remanufacturing operations. However, most of the effort has been focused on developing technology to separate and recover non-metallic materials, such as polymers, from shredder residue. To make future vehicles more energy efficient, more lightweighting materials - primarily polymers, polymer composites, high-strength steels, and aluminum - will be used in manufacturing these

  20. Release and fate of fluorocarbons in a shredder residue landfill cell: 1. Laboratory experiments.

    PubMed

    Scheutz, Charlotte; Fredenslund, Anders M; Nedenskov, Jonas; Kjeldsen, Peter

    2010-11-01

    The shredder residues from automobiles, home appliances and other metal-containing products are often disposed in landfills, as recycling technologies for these materials are not common in many countries. Shredder waste contains rigid and soft foams from cushions and insulation panels blown with fluorocarbons. The objective of this study was to use laboratory experiments to estimate fluorocarbon release and attenuation processes in a monofill shredder residue (SR) landfill cell. Waste from the open SR landfill cell at the AV Miljø landfill in Denmark was sampled at three locations. The waste contained 1-3% metal and a relatively low fraction of rigid polyurethane (PUR) foam particles. The PUR waste contained less blowing agent (CFC-11) than predicted from a release model. However, CFC-11 was steadily released in an aerobic bench scale experiment. Anaerobic waste incubation bench tests showed that SRSR produced significant methane (CH(4)), but at rates that were in the low end of the range observed for municipal solid waste. Aerobic and anaerobic batch experiments showed that processes in SRSR potentially can attenuate the fluorocarbons released from the SRSR itself: CFC-11 is degraded under anaerobic conditions with the formation of degradation products, which are being degraded under CH(4) oxidation conditions prevailing in the upper layers of the SR. PMID:20435458

  1. Leaf litter breakdown, microbial respiration and shredder production in metal-polluted streams

    USGS Publications Warehouse

    Carlisle, D.M.; Clements, W.H.

    2005-01-01

    1. If species disproportionately influence ecosystem functioning and also differ in their sensitivities to environmental conditions, the selective removal of species by anthropogenic stressors may lead to strong effects on ecosystem processes. We evaluated whether these circumstances held for several Colorado, U.S.A. streams stressed by Zn. 2. Benthic invertebrates and chemistry were sampled in five second-third order streams for 1 year. Study streams differed in dissolved metal concentrations, but were otherwise similar in chemical and physical characteristics. Secondary production of leaf-shredding insects was estimated using the increment summation and size-frequency methods. Leaf litter breakdown rates were estimated by retrieving litter-bags over a 171 day period. Microbial activity on leaf litter was measured in the laboratory using changes in oxygen concentration over a 48 h incubation period. 3. Dissolved Zn concentrations varied eightfold among two reference and three polluted streams. Total secondary production of shredders was negatively associated with metal contamination. Secondary production in reference streams was dominated by Taenionema pallidum. Results of previous studies and the current investigation demonstrate that this shredder is highly sensitive to metals in Colorado headwater streams. Leaf litter breakdown rates were similar between reference streams and declined significantly in the polluted streams. Microbial respiration at the most contaminated site was significantly lower than at reference sites. 4. Our results supported the hypothesis that some shredder species contribute disproportionately to leaf litter breakdown. Furthermore, the functionally dominant taxon was also the most sensitive to metal contamination. We conclude that leaf litter breakdown in our study streams lacked functional redundancy and was therefore highly sensitive to contaminant-induced alterations in community structure. We argue for the necessity of simultaneously

  2. Human health and ecological risk assessment of a 100 ton per hour metal shredder

    SciTech Connect

    Belluck, D.; Lynott, W.; Hoff, P.

    1995-12-31

    The Minnesota Pollution Control Agency (MPCA) performed a first of its kind screening level ecological risk assessment (ERA) and human health risk assessment (HHRA) on a proposed 100 ton per hour metal shredder to be located in North Minneapolis. If built, the proposed facility would be located on the Mississippi River, a protected resource surrounded by several urban communities. MSDS data were used to generate numerical release rates to the ambient environment and surrounding communities. Standard risk assessment techniques were employed which calculated potentially significant human (i.e., carcinogenic) and ecological (i.e., several terrestrial receptors) risks. While responding to public comments on the HHRA and ERA reports, MPCA staff identified several additional potential emissions/releases issues requiring additional evaluation including: lead in soil attached to auto parts and other shredder feedstock; mercury in auto parts and switches; chromium and other chemicals in paints and coatings; and PCBs and asbestos in feedstock. This work has demonstrated that a facility originally thought by many to be a minor emitter of metal particulates is, because of its feedstock and location, a potential significant risk to human health and the environment that can only be considered acceptable for permitting with the inclusion of stringent pollution control permit conditions, including a permittee proposed particulate emission rate of 0.43 pounds per hour.

  3. Management status of end-of-life vehicles and characteristics of automobile shredder residues in Korea.

    PubMed

    Kim, Ki-Heon; Joung, Hyun-Tae; Nam, Hoon; Seo, Yong-Chil; Hee Hong, John; Yoo, Tae-Wook; Lim, Bong-Soo; Park, Jin-Ho

    2004-01-01

    An end-of-life vehicle (ELV) is dismantled to recover and recycle any re-usable parts, then shipped to the shredding facility for further recovery of iron with any remaining Automobile Shredder Residue (ASR) to be considered as wastes and to be disposed of by either thermal treatment or landfill. Overall ELVs management status in Korea, including recycling resulting from the dismantling processes, was surveyed using some questionnaires given to dismantlers and other available information to provide some feasible means for future treatment. The averaged recycle rate in the dismantling stage showed a value of 44% and the rest of an ELV was then compressed and transported to shredding companies to recover mainly the iron content which averaged 38.7% of the mass of a new vehicle. The non-ferrous metals such as copper, antimony, zinc and aluminum accounted for only 1.5%. The Shredder dusts (SDs) were found to be composed of light and heavy fluffs and soil/dust and amounted to 15.8% based on the mass of a new vehicle. Dumping of fluff and inorganic residues into a landfill site, however, will be restricted when new regulations are implemented to reduce the disposal amount to less than 5% of a new car as done in European countries and Japan. The detailed characteristics of SDs were investigated to provide an idea of how to treat them in order to meet a future expected enforcement.

  4. Waterborne toxicity and diet-related effects of fungicides in the key leaf shredder Gammarus fossarum (Crustacea: Amphipoda).

    PubMed

    Zubrod, J P; Englert, D; Wolfram, J; Wallace, D; Schnetzer, N; Baudy, P; Konschak, M; Schulz, R; Bundschuh, M

    2015-12-01

    Animals involved in leaf litter breakdown (i.e., shredders) play a central role in detritus-based stream food webs, while their fitness and functioning can be impaired by anthropogenic stressors. Particularly fungicides can affect shredders via both waterborne exposure and their diet, namely due to co-ingestion of adsorbed fungicides and shifts in the leaf-associated fungal community, on which shredders' nutrition heavily relies. To understand the relevance of these effect pathways, we used a full 2×2-factorial test design: the leaf material serving as food was microbially colonized for 12 days either in a fungicide-free control or exposed to a mixture of five current-use fungicides (sum concentration of 62.5μg/L). Similarly, the amphipod shredder Gammarus fossarum was subjected to the same treatments but for 24 days. Waterborne exposure reduced leaf consumption by ∼20%, which did not fully explain the reduction in feces production (∼30%), indicating an enhanced utilization of food to compensate for detoxification mechanisms. This may also explain the reduced feces production (∼10%) of gammarids feeding on fungicide-exposed leaves. The reduction may, however, also be caused by a decreased nutritious quality of the leaves indicated by a reduced species richness (∼40%) of leaf-associated fungi. However, compensation for these effects by Gammarus was seemingly incomplete, since both waterborne exposure and the consumption of the fungicide-affected diet drastically reduced gammarid growth (∼110% and ∼40%, respectively). Our results thus indicate that fungicide mixtures have the potential for detrimental implications in aquatic ecosystem functioning by affecting shredders via both effect pathways. PMID:26520670

  5. Pollutant formation in the pyrolysis and combustion of Automotive Shredder Residue.

    PubMed

    Rey, Lorena; Conesa, Juan A; Aracil, Ignacio; Garrido, Maria A; Ortuño, Nuria

    2016-10-01

    The present work has been carried out to verify the feasibility of thermal valorization of an automobile shredder residue (ASR). With this aim, the thermal decomposition of this waste has been studied in a laboratory scale reactor, analyzing the pollutants emitted under different operating conditions. The emission factors of carbon oxides, light hydrocarbons, PAHs, PCPhs, PCBzs, PBPhs, PCDD/Fs, dioxin-like PCBs and PBDD/Fs were determined at two temperatures, 600 and 850°C, and under different oxygen ratios ranging from 0 (pure pyrolysis) to 1.5 (over-stoichiometric oxidation). After analyzing all these compounds, we conclude that thermal valorization of ASR is a clean way to treat this waste. PMID:27497585

  6. Automotive shredder residue: a survey of the hazardous organic micro-pollutants spectrum in landfill biogas.

    PubMed

    Raboni, Massimo; Torretta, Vincenzo; Urbini, Giordano; Viotti, Paolo

    2015-01-01

    In this study, we report an extensive set of analytical results on the quality of the biogas produced by a landfill of automotive shredder residues. In particular, the investigation was directed towards the identification of a spectrum of polycyclic aromatic hydrocarbons (16 compounds) and a wide range of volatile organic compounds (35 compounds). This article highlights the most important indications of toxicological concern for the detected compounds. Among the polycyclic aromatic hydrocarbons, chrysene shows the highest concentration, followed by pyrene and benzo(b)fluoranthene. Dibenz(a,h)anthracene, the most carcinogenic of the tested compounds, displayed results below the limit of analytical detectability. Benzo(a)pyrene, another typical carcinogenic compound, was detected at low concentrations. With regard to volatile organic compounds, the survey revealed a relevant concentration of toluene (found in fuels and paint thinner) significantly higher than the other compounds. Noticeable amounts of hexane, trichloromethane, and acetone were also found. PMID:25428428

  7. Pollutant formation in the pyrolysis and combustion of Automotive Shredder Residue.

    PubMed

    Rey, Lorena; Conesa, Juan A; Aracil, Ignacio; Garrido, Maria A; Ortuño, Nuria

    2016-10-01

    The present work has been carried out to verify the feasibility of thermal valorization of an automobile shredder residue (ASR). With this aim, the thermal decomposition of this waste has been studied in a laboratory scale reactor, analyzing the pollutants emitted under different operating conditions. The emission factors of carbon oxides, light hydrocarbons, PAHs, PCPhs, PCBzs, PBPhs, PCDD/Fs, dioxin-like PCBs and PBDD/Fs were determined at two temperatures, 600 and 850°C, and under different oxygen ratios ranging from 0 (pure pyrolysis) to 1.5 (over-stoichiometric oxidation). After analyzing all these compounds, we conclude that thermal valorization of ASR is a clean way to treat this waste.

  8. Automotive shredder residue: a survey of the hazardous organic micro-pollutants spectrum in landfill biogas.

    PubMed

    Raboni, Massimo; Torretta, Vincenzo; Urbini, Giordano; Viotti, Paolo

    2015-01-01

    In this study, we report an extensive set of analytical results on the quality of the biogas produced by a landfill of automotive shredder residues. In particular, the investigation was directed towards the identification of a spectrum of polycyclic aromatic hydrocarbons (16 compounds) and a wide range of volatile organic compounds (35 compounds). This article highlights the most important indications of toxicological concern for the detected compounds. Among the polycyclic aromatic hydrocarbons, chrysene shows the highest concentration, followed by pyrene and benzo(b)fluoranthene. Dibenz(a,h)anthracene, the most carcinogenic of the tested compounds, displayed results below the limit of analytical detectability. Benzo(a)pyrene, another typical carcinogenic compound, was detected at low concentrations. With regard to volatile organic compounds, the survey revealed a relevant concentration of toluene (found in fuels and paint thinner) significantly higher than the other compounds. Noticeable amounts of hexane, trichloromethane, and acetone were also found.

  9. Consequences of warming and resource quality on the stoichiometry and nutrient cycling of a stream shredder.

    PubMed

    Mas-Martí, Esther; Romaní, Anna M; Muñoz, Isabel

    2015-01-01

    As a result of climate change, streams are warming and their runoff has been decreasing in most temperate areas. These changes can affect consumers directly by increasing their metabolic rates and modifying their physiology and indirectly by changing the quality of the resources on which organisms depend. In this study, a common stream detritivore (Echinogammarus berilloni Catta) was reared at two temperatures (15 and 20°C) and fed Populus nigra L. leaves that had been conditioned either in an intermittent or permanent reach to evaluate the effects of resource quality and increased temperatures on detritivore performance, stoichiometry and nutrient cycling. The lower quality (i.e., lower protein, soluble carbohydrates and higher C:P and N:P ratios) of leaves conditioned in pools resulted in compensatory feeding and lower nutrient retention capacity by E. berilloni. This effect was especially marked for phosphorus, which was unexpected based on predictions of ecological stoichiometry. When individuals were fed pool-conditioned leaves at warmer temperatures, their growth rates were higher, but consumers exhibited less efficient assimilation and higher mortality. Furthermore, the shifts to lower C:P ratios and higher lipid concentrations in shredder body tissues suggest that structural molecules such as phospholipids are preserved over other energetic C-rich macromolecules such as carbohydrates. These effects on consumer physiology and metabolism were further translated into feces and excreta nutrient ratios. Overall, our results show that the effects of reduced leaf quality on detritivore nutrient retention were more severe at higher temperatures because the shredders were not able to offset their increased metabolism with increased consumption or more efficient digestion when fed pool-conditioned leaves. Consequently, the synergistic effects of impaired food quality and increased temperatures might not only affect the physiology and survival of detritivores but

  10. Consequences of Warming and Resource Quality on the Stoichiometry and Nutrient Cycling of a Stream Shredder

    PubMed Central

    Mas-Martí, Esther; Romaní, Anna M.; Muñoz, Isabel

    2015-01-01

    As a result of climate change, streams are warming and their runoff has been decreasing in most temperate areas. These changes can affect consumers directly by increasing their metabolic rates and modifying their physiology and indirectly by changing the quality of the resources on which organisms depend. In this study, a common stream detritivore (Echinogammarus berilloni Catta) was reared at two temperatures (15 and 20°C) and fed Populus nigra L. leaves that had been conditioned either in an intermittent or permanent reach to evaluate the effects of resource quality and increased temperatures on detritivore performance, stoichiometry and nutrient cycling. The lower quality (i.e., lower protein, soluble carbohydrates and higher C:P and N:P ratios) of leaves conditioned in pools resulted in compensatory feeding and lower nutrient retention capacity by E. berilloni. This effect was especially marked for phosphorus, which was unexpected based on predictions of ecological stoichiometry. When individuals were fed pool-conditioned leaves at warmer temperatures, their growth rates were higher, but consumers exhibited less efficient assimilation and higher mortality. Furthermore, the shifts to lower C:P ratios and higher lipid concentrations in shredder body tissues suggest that structural molecules such as phospholipids are preserved over other energetic C-rich macromolecules such as carbohydrates. These effects on consumer physiology and metabolism were further translated into feces and excreta nutrient ratios. Overall, our results show that the effects of reduced leaf quality on detritivore nutrient retention were more severe at higher temperatures because the shredders were not able to offset their increased metabolism with increased consumption or more efficient digestion when fed pool-conditioned leaves. Consequently, the synergistic effects of impaired food quality and increased temperatures might not only affect the physiology and survival of detritivores but

  11. Value analysis of neodymium content in shredder feed: toward enabling the feasibility of rare earth magnet recycling.

    PubMed

    Bandara, H M Dhammika; Darcy, Julia W; Apelian, Diran; Emmert, Marion H

    2014-06-17

    In order to facilitate the development of recycling technologies for rare earth magnets from postconsumer products, we present herein an analysis of the neodymium (Nd) content in shredder scrap. This waste stream has been chosen on the basis of current business practices for the recycling of steel, aluminum, and copper from cars and household appliances, which contain significant amounts of rare earth magnets. Using approximations based on literature data, we have calculated the average Nd content in the ferrous shredder product stream to be between 0.13 and 0.29 kg per ton of ferrous scrap. A value analysis considering rare earth metal prices between 2002 and 2013 provides values between $1.32 and $145 per ton of ferrous scrap for this material, if recoverable as pure Nd metal. Furthermore, we present an analysis of the content and value of other rare earths (Pr, Dy, Tb).

  12. The role of grazers and shredders in the retention and downstream transport of a PCB in lotic environments

    SciTech Connect

    Sallenave, R.M. . Dept. of Environmental Biology); Day, K.E. ); Kreutzweiser, D.P. . Forest Pest Management Inst.)

    1994-11-01

    Field studies using flow-through artificial stream channels were conducted between May and October 1992 to study the role of the feeding activity of grazing and shredding invertebrates in promoting downstream transport of 2,2[prime],4,4[prime],5,5[prime]-hexachlorobiphenyl (HCBP). Plant material was labeled with [[sup 14]C]HCBP and fed to selected invertebrate species, and accrual of radioactivity by downstream collector species (Hydropsyche spp.) was measured. Downstream transport of HCBP was significantly increased by the presence of the grazer Elimia livescens in the upstream sections of the channels as demonstrated by significantly higher levels of radioactivity in hydropsychid larvae located downstream. Similarly, movement of HCBP downstream was significantly greater in channels containing the shredder Hydatophylax argus than in channels without shredders. These results suggest that the feeding processes of benthic invertebrates may play an important role in the downstream transport of particle-bound hydrophobic organic compounds.

  13. Do climate and soil influence phenotypic variability in leaf litter, microbial decomposition and shredder consumption?

    PubMed

    Graça, M A S; Poquet, J M

    2014-03-01

    We tested the hypothesis that water stress and soil nutrient availability drive leaf-litter quality for decomposers and detritivores by relating chemical and physical leaf-litter properties and decomposability of Alnus glutinosa and Quercus robur, sampled together with edaphic parameters, across wide European climatic gradients. By regressing principal components analysis of leaf traits [N, P, condensed tannins, lignin, specific leaf area (SLA)] against environmental and soil parameters, we found that: (1) In Q. robur the condensed tannin and lignin contents increased and SLA decreased with precipitation, annual range of temperature, and soil N content, whereas leaf P increased with soil P and temperature; (2) In A. glutinosa leaves N, P, and SLA decreased and condensed tannins increased with temperature, annual range of temperature, and decreasing soil P. On the other hand, leaf P and condensed tannins increased and SLA decreased with minimum annual precipitation and towards sites with low temperature. We selected contrasting leaves in terms of quality to test decomposition and invertebrate consumption. There were intraspecific differences in microbial decomposition rates (field, Q. robur) and consumption by shredders (laboratory, A. glutinosa). We conclude that decomposition rates across ecosystems could be partially governed by climate and soil properties, affecting litter quality and therefore decomposers and detritivores. Under scenarios of global warming and increased nutrients, these results suggest we can expect species-specific changes in leaf-litter properties most likely resulting in slow decomposition with increased variance in temperatures and accelerated decomposition with P increase.

  14. Review of Italian experience on automotive shredder residue characterization and management.

    PubMed

    Cossu, R; Fiore, S; Lai, T; Luciano, A; Mancini, G; Ruffino, B; Viotti, P; Zanetti, M C

    2014-10-01

    Automotive Shredder Residue (ASR) is a special waste that can be classified as either hazardous or non hazardous depending on the amount of hazardous substances and on the features of leachate gathered from EN12457/2 test. However both the strict regulation concerning landfills and the EU targets related to End-of-Life Vehicles (ELVs) recovery and recycling rate to achieve by 2015 (Directive 2000/53/EC), will limit current landfilling practice and will impose an increased efficiency of ELVs valorization. The present paper considers ELVs context in Italy, taking into account ASRs physical-chemical features and current processing practice, focusing on the enhancement of secondary materials recovery. The application in waste-to-energy plants, cement kilns or metallurgical processes is also analyzed, with a particular attention to the possible connected environmental impacts. Pyrolysis and gasification are considered as emerging technologies although the only use of ASR is debatable; its mixing with other waste streams is gradually being applied in commercial processes. The environmental impacts of the processes are acceptable, but more supporting data are needed and the advantage over (co-)incineration remains to be proven.

  15. TG-MS study of the thermo-oxidative behavior of plastic automobile shredder residues.

    PubMed

    Guo, Qingjie; Zhang, Xuan; Li, Chao; Liu, Xinmin; Li, Jinhui

    2012-03-30

    Automobile shredder residues (ASR) are materials that are rejected in the metal recovery process for end-of-life vehicles (ELV). These residues are composed of such materials as plastics, foams, glasses, rubbers, textiles, remaining metals and soils. ASR disposal is a difficult task, due to increasingly restrictive re-use policies. The pyrolytic reuse of ASR is one important option for energy recovery. The gas release behavior of pyrolyzed ASR was measured using a TG-MS apparatus, and this thermo-oxidative process was observed under different N(2)/O(2) volume ratios. The final weight/initial residue weight ratio for pyrolyzed ASR decreased from 43.4% to 10.1% with increasing oxygen concentrations. The production rates of hydrogen, methane and carbon dioxide also varied with different N(2)/O(2) volume ratios. The maximum emission of hydrogen and methane occurred when the thermo-oxidative atmosphere was entirely N(2). Temperature had a positive impact on hydrogen production, and the methane emission ratio reached a peak at the second shoulder of the devolatilization stage during which stage organic polymers were emitted. A peculiar characteristic of ASR is its content of nitrogen. The effects of ASR nitrogen content on N(2)O and NO(X) emissions were investigated in detail. NH(3) was the dominant nitrogen species that was released during ASR pyrolysis. N(2)O is highly temperature-sensitive and decomposes to N(2) at temperatures greater than 900°C.

  16. TG-MS study of the thermo-oxidative behavior of plastic automobile shredder residues.

    PubMed

    Guo, Qingjie; Zhang, Xuan; Li, Chao; Liu, Xinmin; Li, Jinhui

    2012-03-30

    Automobile shredder residues (ASR) are materials that are rejected in the metal recovery process for end-of-life vehicles (ELV). These residues are composed of such materials as plastics, foams, glasses, rubbers, textiles, remaining metals and soils. ASR disposal is a difficult task, due to increasingly restrictive re-use policies. The pyrolytic reuse of ASR is one important option for energy recovery. The gas release behavior of pyrolyzed ASR was measured using a TG-MS apparatus, and this thermo-oxidative process was observed under different N(2)/O(2) volume ratios. The final weight/initial residue weight ratio for pyrolyzed ASR decreased from 43.4% to 10.1% with increasing oxygen concentrations. The production rates of hydrogen, methane and carbon dioxide also varied with different N(2)/O(2) volume ratios. The maximum emission of hydrogen and methane occurred when the thermo-oxidative atmosphere was entirely N(2). Temperature had a positive impact on hydrogen production, and the methane emission ratio reached a peak at the second shoulder of the devolatilization stage during which stage organic polymers were emitted. A peculiar characteristic of ASR is its content of nitrogen. The effects of ASR nitrogen content on N(2)O and NO(X) emissions were investigated in detail. NH(3) was the dominant nitrogen species that was released during ASR pyrolysis. N(2)O is highly temperature-sensitive and decomposes to N(2) at temperatures greater than 900°C. PMID:22316686

  17. Recycling of a fine, heavy fluff automobile shredder residue by density and differential fragmentation.

    PubMed

    Gent, M R; Menéndez, M; Muñiz, H; Torno, S

    2015-09-01

    A compilation of the physical properties of materials which might typically occur in automobile shredder residue and an analysis of their suitability for the separation of materials in fine (<15mm) heavy fluff ASR (fhf-ASR) is presented. Differences in density and resistance to crushing of fhf-ASR materials were identified as potentially the most suitable low cost, technologically simple means for the separating this waste into its three principal components - metals, minerals (glass/stones) and organics (plastics). Results presented of laboratory scale tests demonstrate that fhf-ASR can in large part be separated into three principal components. Tests were conducted with 0.63-2.0mm and 2-10mm fractions. Recovery of plastics by density separations were conducted with water only jigs for the 2-10mm fraction and shaker tables for the 0.63-2mm fraction. Comparisons are presented of the separations of glass and stones from metals obtained by linear screening and vibratory screening of roller mill and impact mill crushing products of the high density 2-10mm fraction. Equipment used for these tests are of a laboratory or demonstrative scale. It is reasonable to anticipate that industrial scale processing would produce significantly better results. The 2-15mm fraction was found to constitute 91.6% of the fhf-ASR sampled. The metals content of the 2-10mm portion of this fraction was upgraded from 2.5% to 31% and 76.9% with recoveries varying inversely with grade from 91.9% to 40.1%. From 63.6% to 17.1% with a recovery of 93.5% of the organic materials. A residual product of fine sand of crushed glass/stones of 99.4% purity recovered 71.3% of these.

  18. Life cycle assessment of innovative technology for energy production from automotive shredder residue.

    PubMed

    Rinaldi, Caterina; Masoni, Paolo; Salvati, Fabio; Tolve, Pietro

    2015-07-01

    Automotive Shredder Residue (ASR) is a problematic waste material remaining after shredding and recovery processes of end-of-life vehicles (ELVs). Its heterogeneous grain size and composition make difficult its recovery or disposal. Although ASR accounts for approximately 20% to 25% of the weight of an ELV, the European Union (EU)'s ELV Directive (2000/53/EC) requires that by 2015 a minimum 95% of the weight of an ELV must be reused or recovered, including a 10% weight energy recovery. The quantity of ASR is relevant: Approximately 2.4 million tons are generated in the EU each year and most of it is sent to landfills. This article describes a life cycle model of the "TEKNE-Fluff" process designed to make beneficial use of ASR that is based on the results of an experimental pilot plant for pyro-gasification, combustion, cogeneration, and emissions treatment of ASR. The goal of the research was the application of life cycle assessment (LCA) methodology to identify the environmental hot spots of the "TEKNE system" and use scenario analysis to check solutions to improve its environmental profile, supporting the design and industrialization process. The LCA was conducted based on data modeled from the experimental campaign. Moreover, different scenarios on shares of electricity and thermal energy produced by the cogeneration system and alternative treatment processes for the waste produced by the technology were compared. Despite the limitation of the research (results based on scaling up experimental data by modeling), impact assessment results are promising and sufficiently robust, as shown by Monte Carlo analysis. The TEKNE technology may become an interesting solution for the problem of ASR management: Besides representing an alternative to landfill disposal, the energy produced could avoid significant impacts on fossil resources depletion (a plant of 40,000 tons/y capacity could produce ∼ 147,000 GJ/yr, covering the annual need of ∼ 13,500 households).

  19. Life cycle assessment of innovative technology for energy production from automotive shredder residue.

    PubMed

    Rinaldi, Caterina; Masoni, Paolo; Salvati, Fabio; Tolve, Pietro

    2015-07-01

    Automotive Shredder Residue (ASR) is a problematic waste material remaining after shredding and recovery processes of end-of-life vehicles (ELVs). Its heterogeneous grain size and composition make difficult its recovery or disposal. Although ASR accounts for approximately 20% to 25% of the weight of an ELV, the European Union (EU)'s ELV Directive (2000/53/EC) requires that by 2015 a minimum 95% of the weight of an ELV must be reused or recovered, including a 10% weight energy recovery. The quantity of ASR is relevant: Approximately 2.4 million tons are generated in the EU each year and most of it is sent to landfills. This article describes a life cycle model of the "TEKNE-Fluff" process designed to make beneficial use of ASR that is based on the results of an experimental pilot plant for pyro-gasification, combustion, cogeneration, and emissions treatment of ASR. The goal of the research was the application of life cycle assessment (LCA) methodology to identify the environmental hot spots of the "TEKNE system" and use scenario analysis to check solutions to improve its environmental profile, supporting the design and industrialization process. The LCA was conducted based on data modeled from the experimental campaign. Moreover, different scenarios on shares of electricity and thermal energy produced by the cogeneration system and alternative treatment processes for the waste produced by the technology were compared. Despite the limitation of the research (results based on scaling up experimental data by modeling), impact assessment results are promising and sufficiently robust, as shown by Monte Carlo analysis. The TEKNE technology may become an interesting solution for the problem of ASR management: Besides representing an alternative to landfill disposal, the energy produced could avoid significant impacts on fossil resources depletion (a plant of 40,000 tons/y capacity could produce ∼ 147,000 GJ/yr, covering the annual need of ∼ 13,500 households). PMID

  20. Predation Risk versus Pesticide Exposure: Consequences of Fear and Loathing in the Life of Stream Shredders

    NASA Astrophysics Data System (ADS)

    Pestana, J. T.; Baird, D. J.; Soares, A. M.

    2005-05-01

    Stream invertebrates are exposed to complex stressor regimes including both biotic and abiotic factors. Species living in streams in agricultural landscapes are often subjected to episodic or continuous exposures to low levels of agrochemicals, which may approach or exceed specific substance guidelines. Sublethal effects of pesticides may result in direct effects on organisms (e.g. reduced physiological performance), which may in turn contribute to indirect effects relating to survival (e.g. increased predation risk). Here, we investigate the possibility that predator-release kairomones can act additively with low-level pesticide exposure to reduce physiological performance and survival of stream invertebrates in previously unforeseen ways. Feeding, metabolic and behavioural responses of two shredder insects, the North American stonefly Pteronarcys comstockii and the European caddisfly Sericostoma vittatum were measured under exposure to the insecticide imidacloprid at different levels of indirect predation stress using predator-release kairomones from Brown Trout (Salmo trutta). Pteronarcys feeding was measured in terms of mass of naturally conditioned alder leaf discs consumed over a 6-day and 10 -day period in animals held in cages in stream mesocosms. Pteronarcys feeding was impaired at 1 ppb in the 6-day trial and at 0,5 ppb in the 10-day trial relatively to unexposed controls. Metabolic rate was measured in the lab in terms of oxygen consumption of Pteronarcys. Animals exposed to 0.5 and 1 ppb imidacloprid showed elevated respiratory rates compared to controls. Laboratory experiments with Sericostoma, currently in progress, are examining the separate and combined effects of imidacloprid and predator kairomone on similar endpoints. These preliminary results are discussed in relation to the development of the Mechanistic Unifying Stressor Effects (MUSE) model which can be used to predict combined ecological effects of multiple stressors at the population level.

  1. Separation of polyvinyl chloride (PVC) from automobile shredder residue (ASR) by froth flotation with ozonation.

    PubMed

    Reddy, Mallampati Srinivasa; Kurose, Keisuke; Okuda, Tetsuji; Nishijima, Wataru; Okada, Mitsumasa

    2007-08-25

    The purpose of this study is to develop froth flotation to separate polyvinyl chloride (PVC) from automobile shredder residue (ASR) plastic mixtures of variable composition. Some polymers in ASR polymer mixtures have similar density and hydrophobicity with PVC and thus selective flotation of PVC from ASR polymer mixtures cannot be achieved. The present study focused on the surface modification of PVC with ozonation, and then the modified PVC can be separated from other polymers by the following froth flotation. The results of this study indicate that the selective recovery of PVC from real ASR polyethylene tetra pethelate (PET), polymethyl methacrylate (PMMA), polybutyl methacralate (PBMA), ethyl acrylate (EA), polycarbonate (PC) and rubber mixtures can be accomplished in a three-step process involving a gravity separation, ozonation and froth flotation. The rubber was removed from other heavy ASR (PVC, PET, PMMA, PBMA, EA and PC) polymers by froth flotation without mixing. It was found that ozonation process produced the desired difference in contact angle required (from 89.5 to 73.0 degrees ) for separation of PVC from other heavy ASR polymers, whereas the contact angles of other polymers was slightly decreased. The most of the load ASR, i.e. about 72.4% is floated away and 27.6% was settled down. The highest component 96.7% of PVC was recovered in the settled fraction. As a result of this research effort, the surface modification of PVC with ozonation can be efficiently useful to separate the PVC from other similar density ASR mixed polymers. PMID:17360113

  2. Recycling of a fine, heavy fluff automobile shredder residue by density and differential fragmentation.

    PubMed

    Gent, M R; Menéndez, M; Muñiz, H; Torno, S

    2015-09-01

    A compilation of the physical properties of materials which might typically occur in automobile shredder residue and an analysis of their suitability for the separation of materials in fine (<15mm) heavy fluff ASR (fhf-ASR) is presented. Differences in density and resistance to crushing of fhf-ASR materials were identified as potentially the most suitable low cost, technologically simple means for the separating this waste into its three principal components - metals, minerals (glass/stones) and organics (plastics). Results presented of laboratory scale tests demonstrate that fhf-ASR can in large part be separated into three principal components. Tests were conducted with 0.63-2.0mm and 2-10mm fractions. Recovery of plastics by density separations were conducted with water only jigs for the 2-10mm fraction and shaker tables for the 0.63-2mm fraction. Comparisons are presented of the separations of glass and stones from metals obtained by linear screening and vibratory screening of roller mill and impact mill crushing products of the high density 2-10mm fraction. Equipment used for these tests are of a laboratory or demonstrative scale. It is reasonable to anticipate that industrial scale processing would produce significantly better results. The 2-15mm fraction was found to constitute 91.6% of the fhf-ASR sampled. The metals content of the 2-10mm portion of this fraction was upgraded from 2.5% to 31% and 76.9% with recoveries varying inversely with grade from 91.9% to 40.1%. From 63.6% to 17.1% with a recovery of 93.5% of the organic materials. A residual product of fine sand of crushed glass/stones of 99.4% purity recovered 71.3% of these. PMID:26119010

  3. Pollution control and metal resource recovery for low grade automobile shredder residue: a mechanism, bioavailability and risk assessment.

    PubMed

    Singh, Jiwan; Lee, Byeong-Kyu

    2015-04-01

    Automobile shredder residue (ASR) is considered as hazardous waste in Japan and European countries due to presence of heavy metals. This study was carried on the extraction characteristics of heavy metals (Mn, Fe, Ni, and Cr) from automobile shredder residue (ASR). The effects of pH, temperature, particle size, and liquid/solid ratio (L/S) on the extraction of heavy metals were investigated. The recovery rate of Mn, Fe, Ni, and Cr increased with increasing extraction temperature and L/S ratio. The lowest pH 2, the highest L/S ratio, and the smallest particle size showed the highest recovery of heavy metals from ASR. The highest recovery rates were in the following order: Mn > Ni > Cr > Fe. Reduction of mobility factor for the heavy metals was observed in all the size fractions after the recovery. The results of the kinetic analysis for various experimental conditions supported that the reaction rate of the recovery process followed a second order reaction model (R(2) ⩾ 0.95). The high availability of water-soluble fractions of Mn, Fe, Ni, and Cr from the low grade ASR could be potential hazards to the environment. Bioavailability and toxicity risk of heavy metals reduced significantly with pH 2 of distilled water. However, water is a cost-effective extracting agent for the recovery of heavy metals and it could be useful for reducing the toxicity of ASR.

  4. Strategies for the enhancement of automobile shredder residues (ASRs) recycling: results and cost assessment.

    PubMed

    Ruffino, Barbara; Fiore, Silvia; Zanetti, Maria Chiara

    2014-01-01

    With reference to the European regulation about the management of End-of-Life Vehicles (ELVs), Directive 2000/53/EC imposes the achievement of a recycling target of 85%, and 95% of total recovery by 2015. Over the last few years many efforts have been made to find solutions to properly manage the waste coming from ELVs with the aim of complying with the targets fixed by the Directive. This paper focuses on the economical evaluation of a treatment process, that includes physical (size and density), magnetic and electrical separations, performed on the light fraction of the automobile shredder residue (ASR) with the aim of reducing the amount of waste to dispose of in a landfill and enhancing the recovery of valuable fractions as stated by the EU Directive. The afore mentioned process is able to enhance the recovery of ferrous and non-ferrous metals of an amount equal to about 1% b.w. (by weight) of the ELV weight, and to separate a high energetic-content product suitable for thermal valorization for an amount close to (but not higher than) 10% b.w. of the ELV weight. The results of the economical assessment led to annual operating costs of the treatment ranging from 300,000 €/y to 350,000 €/y. Since the considered plant treats about 13,500 metrictons of ASR per year, this would correspond to an operating cost of approximately 20-25 €/t. Taking into account the amount and the selling price of the scrap iron and of the non magnetic metal recovered by the process, thus leading to a gain of about 30 €/t per ton of light ASR treated, the cost of the recovery process is balanced by the profit from the selling of the recovered metals. On the other hand, the proposed treatment is able to achieve the fulfillment of the targets stated by Directive 2000/53/EC concerning thermal valorization and reduce the amount of waste generated from ELV shredding to landfill.

  5. Leachability of automotive shredder residues burned in a fluidized bed system.

    PubMed

    Lopes, M H; Freire, M; Galhetas, M; Gulyurtlu, I; Cabrita, I

    2009-05-01

    This paper presents the results of the study of a combustible fraction of automotive shredder residues (CASRs) and the corresponding ashes generated by combustion on a fluidized bed pilot with the aim to understand the influence of thermal treatment regarding properties for final disposal, such as landfilling. The chemical composition was evaluated and the leachability behaviour of ashes and CASR was investigated using the three more commonly used tests: the European Standard EN 12457, the US TCLP-EPA 1311 and the Dutch availability test EA NEN 7371. Different results were obtained depending on the specific conditions of the methods employed. It was found that both the CASR and the ashes contained large amounts of toxic metals and other undesirable elements, such as Cl and S. For the CASR, in addition to the leachability of organic matter above the limit set for hazardous materials, the release of heavy metals, either under alkaline and acidic conditions was significant, revealing the serious risks associated to the landfilling practices still being undertaken worldwide. Release of organic matter from ashes was insignificant, but solubility of sulphates increased and chlorides exceed the hazardous limits in the case of fly ashes. Toxic metals were found to leach from the ashes only under acidic conditions, except Pb and Cu which also leached from finer ashes at alkaline pH. Cr also leached from ashes at alkaline pH values. Both the Dutch availability and TCLP revealed much higher leaching intensities than the European Standard due to the acidity of leachants. However, it was found that ashes may be more resistant to acidification because they exhibit much higher acid neutralization capacity (ANC) than the untreated CASR. The study undertaken shows that thermal valorisation of the combustible fraction of ASR may avoid the risks associated with their landfilling; however, care has to be taken with the ashes because they also behave as hazardous residues. Although

  6. Effects of invasive European bird cherry (Prunus padus) on leaf litter processing by aquatic invertebrate shredder communities in urban Alaskan streams

    USGS Publications Warehouse

    Roon, David A.; Wipfli, Mark S.; Wurtz, Tricia L.

    2014-01-01

    European bird cherry (Prunus padus) (EBC) is an invasive ornamental tree that is spreading rapidly in riparian forests of urban Alaska. To determine how the spread of EBC affects leaf litter processing by aquatic invertebrate shredders, we conducted complementary leaf pack experiments in two streams located in Anchorage, Alaska. The first experiment contrasted invasive EBC with three native tree species—thin-leaf alder (Alnus tenuifolia), paper birch (Betula neoalaskana), and black cottonwood (Populus trichocarpa)—in one reach of Chester Creek; finding that EBC leaf litter broke down significantly faster than birch and cottonwood, but at a similar rate to alder. The second experiment contrasted EBC with alder in four reaches of Campbell and Chester creeks; finding that while EBC leaf litter broke down significantly faster than alder in Chester Creek, EBC broke down at a similar rate to alder in Campbell Creek. Although EBC sometimes supported fewer shredders by both count and mass, shredder communities did not differ significantly between EBC and native plants. Collectively, these data suggest that invasive EBC is not currently exhibiting strong negative impacts on leaf litter processing in these streams, but could if it continues to spread and further displaces native species over time.

  7. Innovative market-based policy instruments for waste management: A case study on shredder residues in Belgium.

    PubMed

    Dubois, Maarten; Hoogmartens, Rob; Van Passel, Steven; Van Acker, Karel; Vanderreydt, Ive

    2015-10-01

    In an increasingly complex waste market, market-based policy instruments, such as disposal taxes, can give incentives for sustainable progress while leaving flexibility for innovation. However, implementation of disposal taxes is often criticised by domestic waste handlers that fear to be outcompeted by competitors in other countries. The article discusses three innovative market-based instruments that limit the impact on international competitiveness: Tradable recycling credits, refunded disposal taxes and differentiated disposal taxes. All three instruments have already been implemented for distinct environmental policies in Europe. In order to illustrate how these instruments can be used for waste policy, the literature review is complemented with a case study on shredder residues from metal-containing waste streams in Belgium. The analysis shows that a conventional disposal tax remains the most efficient, simple and transparent instrument. However, if international competition is a significant issue or if political support is weak, refunded and differentiated disposal taxes can have an added value as second-best instruments. Tradable recycling credits are not an appropriate instrument for use in small waste markets with market power. In addition, refunded taxes create similar incentives, but induce lower transactions costs. PMID:26395844

  8. Mass balance for POPs in a real scale fluidized bed combustor co-incinerating automotive shredder residue.

    PubMed

    Van Caneghem, J; Block, C; Vermeulen, I; Van Brecht, A; Van Royen, P; Jaspers, M; Wauters, G; Vandecasteele, C

    2010-09-15

    The European directive 2000/53/EC implies a "reuse and recovery" rate for end-of-life vehicles (ELVs) of 95% to be reached by the year 2015. One of the options to increase the actual average European "reuse and recovery" rate of approximately 78% (EU 15, 2008) is incineration of automotive shredder residue (ASR) with energy-recovery. The mass balance and the congener fingerprints for PCDD/Fs, dioxin-like PCBs, PCBs and PAHs in a real scale fluidized bed combustor (FBC) incinerating 25% ASR with 25% refuse derived fuel (RDF) and 50% waste water treatment sludge (WWT sludge) were investigated. The PCDD/F, dioxin-like PCB, PCB and PAH concentrations in this input waste mix were more than hundred times higher than in the usual waste feed of the incinerator (30% RFD and 70% WWT sludge). In the outputs of the FBC, however, the concentrations of these POP groups were comparable or only slightly higher than in the outputs generated during the incineration of the usual waste feed. The considered POPs in the waste were destroyed efficiently and the formation of new POPs during cooling of the flue gas appeared to a large extent independent of the POP concentrations in the incinerated waste.

  9. Innovative market-based policy instruments for waste management: A case study on shredder residues in Belgium.

    PubMed

    Dubois, Maarten; Hoogmartens, Rob; Van Passel, Steven; Van Acker, Karel; Vanderreydt, Ive

    2015-10-01

    In an increasingly complex waste market, market-based policy instruments, such as disposal taxes, can give incentives for sustainable progress while leaving flexibility for innovation. However, implementation of disposal taxes is often criticised by domestic waste handlers that fear to be outcompeted by competitors in other countries. The article discusses three innovative market-based instruments that limit the impact on international competitiveness: Tradable recycling credits, refunded disposal taxes and differentiated disposal taxes. All three instruments have already been implemented for distinct environmental policies in Europe. In order to illustrate how these instruments can be used for waste policy, the literature review is complemented with a case study on shredder residues from metal-containing waste streams in Belgium. The analysis shows that a conventional disposal tax remains the most efficient, simple and transparent instrument. However, if international competition is a significant issue or if political support is weak, refunded and differentiated disposal taxes can have an added value as second-best instruments. Tradable recycling credits are not an appropriate instrument for use in small waste markets with market power. In addition, refunded taxes create similar incentives, but induce lower transactions costs.

  10. Hydrometallurgical recovery of heavy metals from low grade automobile shredder residue (ASR): An application of advanced Fenton process (AFP).

    PubMed

    Singh, Jiwan; Lee, Byeong-Kyu

    2015-09-15

    To investigate the leaching and recovery of heavy metals from low-grade automobile shredder residue (ASR), the effects of nitric acid (HNO3) and hydrogen peroxide (H2O2) concentrations, liquid/solid (L/S) ratio, leaching temperature and ASR particle size fractions on the heavy metal leaching rate were determined. The heavy metals were recovered by fractional precipitation and advanced Fenton process (AFP) at different pHs. The toxicity characteristic leaching procedure (TCLP) test was also performed in the residue remaining after heavy metal leaching to evaluate the potential toxicity of ASR. The heavy metal leaching efficiency was increased with increasing HNO3 and H2O2 concentrations, L/S ratio and temperature. The heavy metal leaching efficiencies were maximized in the lowest ASR size fraction at 303 K and L/S ratio of 100 mL/g. The kinetic study showed that the metal leaching was best represented by a second-order reaction model, with a value of R(2) > 0.99 for all selected heavy metals. The determined activation energy (kJ/mol) was 21.61, 17.10, 12.15, 34.50, 13.07 and 11.45 for Zn, Fe, Ni, Pb, Cd and Cr, respectively. In the final residue, the concentrations of Cd, Cr and Pb were under their threshold limits in all ASR size fractions. Hydrometallurgical metal recovery was greatly increased by AFP up to 99.96% for Zn, 99.97% for Fe, 95.62% for Ni, 99.62% for Pb, 94.11% for Cd and 96.79% for Cr. AFP is highly recommended for the recovery of leached metals from solution even at low concentrations. PMID:26143080

  11. Hydrometallurgical recovery of heavy metals from low grade automobile shredder residue (ASR): An application of advanced Fenton process (AFP).

    PubMed

    Singh, Jiwan; Lee, Byeong-Kyu

    2015-09-15

    To investigate the leaching and recovery of heavy metals from low-grade automobile shredder residue (ASR), the effects of nitric acid (HNO3) and hydrogen peroxide (H2O2) concentrations, liquid/solid (L/S) ratio, leaching temperature and ASR particle size fractions on the heavy metal leaching rate were determined. The heavy metals were recovered by fractional precipitation and advanced Fenton process (AFP) at different pHs. The toxicity characteristic leaching procedure (TCLP) test was also performed in the residue remaining after heavy metal leaching to evaluate the potential toxicity of ASR. The heavy metal leaching efficiency was increased with increasing HNO3 and H2O2 concentrations, L/S ratio and temperature. The heavy metal leaching efficiencies were maximized in the lowest ASR size fraction at 303 K and L/S ratio of 100 mL/g. The kinetic study showed that the metal leaching was best represented by a second-order reaction model, with a value of R(2) > 0.99 for all selected heavy metals. The determined activation energy (kJ/mol) was 21.61, 17.10, 12.15, 34.50, 13.07 and 11.45 for Zn, Fe, Ni, Pb, Cd and Cr, respectively. In the final residue, the concentrations of Cd, Cr and Pb were under their threshold limits in all ASR size fractions. Hydrometallurgical metal recovery was greatly increased by AFP up to 99.96% for Zn, 99.97% for Fe, 95.62% for Ni, 99.62% for Pb, 94.11% for Cd and 96.79% for Cr. AFP is highly recommended for the recovery of leached metals from solution even at low concentrations.

  12. Type B accident investigation board report of the July 2, 1997 curium intake by shredder operator at Building 513 Lawrence Livermore National Laboratory, Livermore, California. Final report

    SciTech Connect

    1997-08-01

    On July 2, 1997 at approximately 6:00 A.M., two operators (Workers 1 and 2), wearing approved personal protective equipment (PPE), began a shredding operation of HEPA filters for volume reduction in Building 513 (B-513) at Lawrence Livermore National Laboratory (LLNL). The waste requisitions indicated they were shredding filters containing {le} 1 {micro}Ci of americium-241 (Am-241). A third operator (Worker 3) provided support to the shredder operators in the shredding area (hot area) from a room that was adjacent to the shredding area (cold area). At Approximately 8:00 A.M., a fourth operator (Worker 4) relieved Worker 2 in the shredding operation. Sometime between 8:30 A.M. and 9:00 A.M., Worker 3 left the cold area to make a phone call and set off a hand and foot counter in Building 514. Upon discovering the contamination, the shredding operation was stopped and surveys were conducted in the shredder area. Surveys conducted on the workers found significant levels of contamination on their PPE and the exterior of their respirator cartridges. An exit survey of Worker 1 was conducted at approximately 10:05 A.M., and found contamination on his PPE, as well as on the exterior and interior of his respirator. Contamination was also found on his face, chest, back of neck, hair, knees, and mustache. A nose blow indicated significant contamination, which was later determined to be curium-244.

  13. Optimization of wet shaking table process using response surface methodology applied to the separation of copper and aluminum from the fine fraction of shredder ELVs.

    PubMed

    Jordão, Helga; Sousa, António Jorge; Carvalho, M Teresa

    2016-02-01

    With the purpose of reducing the waste generated by end-of-life vehicles (ELVs) by enhancing the recovery and recycling of nonferrous metals, an experimental study was conducted with the finest size fraction of nonferrous stream produced at an ELV shredder plant. The aim of this work was to characterize the nonferrous stream and to evaluate the efficiency of a gravity concentration process in separating light and heavy nonferrous metal particles that could be easily integrated in a ELV shredder plant (in this case study the separation explicitly addressed copper and aluminum separation). The characterization of a sample of the 0-10mm particle size fraction showed a mixture of nonferrous metals with a certain degree of impurity due to the present of contaminants such as plastics. The majority of the particles exhibited a wire shape, preventing an efficient separation of materials without prior fragmentation. The gravity concentration process selected for this study was the wet shaking table and three operating parameters of the equipment were manipulated. A full factorial design in combination with a central composite design was employed to model metals recovery. Two second order polynomial equations were successfully fitted to describe the process and predict the recovery of copper and aluminum in Cu concentrate under the conditions of the present study. The optimum conditions were determined to be 11.1° of inclination, 2.8L/min of feed water flow and 4.9L/min of wash water flow. All three final products of the wet shaking table had a content higher than 90% in relation to one of the metals, wherein a Cu concentrate product was obtained with a Cu content of 96%, and 78% of Cu recovery and 2% of Al recovery. PMID:26470828

  14. Preliminary investigation on the thermal conversion of automotive shredder residue into value-added products: Graphitic carbon and nano-ceramics.

    PubMed

    Mayyas, Mohannad; Pahlevani, Farshid; Handoko, Wilson; Sahajwalla, Veena

    2016-04-01

    Large increasing production volumes of automotive shredder residue (ASR) and its hazardous content have raised concerns worldwide. ASR has a desirable calorific value, making its pyrolysis a possible, environmentally friendly and economically viable solution. The present work focuses on the pyrolysis of ASR at temperatures between 950 and 1550°C. Despite the high temperatures, the energy consumption can be minimized as the decomposition of ASR can be completed within a short time. In this study, the composition of ASR was investigated. ASR was found to contain about 3% Ti and plastics of high calorific value such as polypropylene, polyethylene, polycarbonate and polyurethane. Based on thermogravimetric analysis (TGA) of ASR, the non-isothermal degradation kinetic parameters were determined using Coats-Redfern's and Freeman and Carroll methods. The evolved gas analysis indicated that the CH4 was consumed by the reduction of some oxides in ASR. The reduction reactions and the presence of Ti, silicates, C and N in ASR at 1550°C favor the formation of specific ceramics such as TiN and SiC. The presence of nano-ceramics along with a highly-crystalline graphitic carbon in the pyrolysis residues obtained at 1550°C was confirmed by scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and Raman imaging microscope (RIM) analyses. PMID:26876777

  15. Utilization of automotive shredder residues in a thermal process for recovery of manganese and zinc from zinc-carbon and alkaline spent batteries.

    PubMed

    Ippolito, N M; Belardi, G; Medici, F; Piga, L

    2016-05-01

    The aim of the study is the recovery by thermal treatment of manganese and zinc from a mixture of zinc-carbon and alkaline spent batteries, on the basis of the different phase change temperatures of the two metal-bearing phases. ASR (Automotive Shredder Residue), containing 68% of carbon, was added to the mixture to act as a reductant to metallic Zn of the zinc-bearing phases. The mixture was subsequently heated in different atmospheres (air, CO2 and N2) and at different temperatures (900°C, 1000°C and 1200°C) and stoichiometric excess of ASR (300%, 600% and 900%). Characterization of the mixture and of the residues of thermal treatment was carried out by chemical analysis, TGA/DTA, SEM and XRD. The results show that recovery of 99% of zinc (grade 97%) is achieved at 1000°C in N2 with a stoichiometric excess of car-fluff of 900%. This product could be suitable for production of new batteries after refining by hydrometallurgical way. Recovery of Mn around 98% in the residue of the treatment is achieved at any temperature and atmosphere tested with a grade of 57% at 900% excess of car-fluff. This residue is enriched in manganese oxide and could be used in the production of iron-manganese alloys. PMID:26777778

  16. Utilization of automotive shredder residues in a thermal process for recovery of manganese and zinc from zinc-carbon and alkaline spent batteries.

    PubMed

    Ippolito, N M; Belardi, G; Medici, F; Piga, L

    2016-05-01

    The aim of the study is the recovery by thermal treatment of manganese and zinc from a mixture of zinc-carbon and alkaline spent batteries, on the basis of the different phase change temperatures of the two metal-bearing phases. ASR (Automotive Shredder Residue), containing 68% of carbon, was added to the mixture to act as a reductant to metallic Zn of the zinc-bearing phases. The mixture was subsequently heated in different atmospheres (air, CO2 and N2) and at different temperatures (900°C, 1000°C and 1200°C) and stoichiometric excess of ASR (300%, 600% and 900%). Characterization of the mixture and of the residues of thermal treatment was carried out by chemical analysis, TGA/DTA, SEM and XRD. The results show that recovery of 99% of zinc (grade 97%) is achieved at 1000°C in N2 with a stoichiometric excess of car-fluff of 900%. This product could be suitable for production of new batteries after refining by hydrometallurgical way. Recovery of Mn around 98% in the residue of the treatment is achieved at any temperature and atmosphere tested with a grade of 57% at 900% excess of car-fluff. This residue is enriched in manganese oxide and could be used in the production of iron-manganese alloys.

  17. Preliminary investigation on the thermal conversion of automotive shredder residue into value-added products: Graphitic carbon and nano-ceramics.

    PubMed

    Mayyas, Mohannad; Pahlevani, Farshid; Handoko, Wilson; Sahajwalla, Veena

    2016-04-01

    Large increasing production volumes of automotive shredder residue (ASR) and its hazardous content have raised concerns worldwide. ASR has a desirable calorific value, making its pyrolysis a possible, environmentally friendly and economically viable solution. The present work focuses on the pyrolysis of ASR at temperatures between 950 and 1550°C. Despite the high temperatures, the energy consumption can be minimized as the decomposition of ASR can be completed within a short time. In this study, the composition of ASR was investigated. ASR was found to contain about 3% Ti and plastics of high calorific value such as polypropylene, polyethylene, polycarbonate and polyurethane. Based on thermogravimetric analysis (TGA) of ASR, the non-isothermal degradation kinetic parameters were determined using Coats-Redfern's and Freeman and Carroll methods. The evolved gas analysis indicated that the CH4 was consumed by the reduction of some oxides in ASR. The reduction reactions and the presence of Ti, silicates, C and N in ASR at 1550°C favor the formation of specific ceramics such as TiN and SiC. The presence of nano-ceramics along with a highly-crystalline graphitic carbon in the pyrolysis residues obtained at 1550°C was confirmed by scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and Raman imaging microscope (RIM) analyses.

  18. Evaluation of heavy metals in hazardous automobile shredder residue thermal residue and immobilization with novel nano-size calcium dispersed reagent.

    PubMed

    Lee, Chi-Hyeon; Truc, Nguyen Thi Thanh; Lee, Byeong-Kyu; Mitoma, Yoshiharu; Mallampati, Srinivasa Reddy

    2015-10-15

    This study was conducted to synthesize and apply a nano-size calcium dispersed reagent as an immobilization material for heavy metal-contaminated automobile shredder residues (ASR) dust/thermal residues in dry condition. Simple mixing with a nanometallic Ca/CaO/PO4 dispersion mixture immobilized 95-100% of heavy metals in ASR dust/thermal residues (including bottom ash, cavity ash, boiler and bag filter ash). The quantity of heavy metals leached from thermal residues after treatment by nanometallic Ca/CaO/PO4 was lower than the Korean standard regulatory limit for hazardous waste landfills. The morphology and elemental composition of the nanometallic Ca/CaO-treated ASR residue were characterized by field emission scanning election microscopy combined with electron dispersive spectroscopy (FE-SEM/EDS). The results indicated that the amounts of heavy metals detectable on the ASR thermal residue surface decreased and the Ca/PO4 mass percent increased. X-ray diffraction (XRD) pattern analysis indicated that the main fraction of enclosed/bound materials on ASR residue included Ca/PO4- associated crystalline complexes, and that immobile Ca/PO4 salts remarkably inhibited the desorption of heavy metals from ASR residues. These results support the potential use of nanometallic Ca/CaO/PO4 as a simple, suitable and highly efficient material for the gentle immobilization of heavy metals in hazardous ASR thermal residue in dry condition. PMID:25935297

  19. Evaluation of heavy metals in hazardous automobile shredder residue thermal residue and immobilization with novel nano-size calcium dispersed reagent.

    PubMed

    Lee, Chi-Hyeon; Truc, Nguyen Thi Thanh; Lee, Byeong-Kyu; Mitoma, Yoshiharu; Mallampati, Srinivasa Reddy

    2015-10-15

    This study was conducted to synthesize and apply a nano-size calcium dispersed reagent as an immobilization material for heavy metal-contaminated automobile shredder residues (ASR) dust/thermal residues in dry condition. Simple mixing with a nanometallic Ca/CaO/PO4 dispersion mixture immobilized 95-100% of heavy metals in ASR dust/thermal residues (including bottom ash, cavity ash, boiler and bag filter ash). The quantity of heavy metals leached from thermal residues after treatment by nanometallic Ca/CaO/PO4 was lower than the Korean standard regulatory limit for hazardous waste landfills. The morphology and elemental composition of the nanometallic Ca/CaO-treated ASR residue were characterized by field emission scanning election microscopy combined with electron dispersive spectroscopy (FE-SEM/EDS). The results indicated that the amounts of heavy metals detectable on the ASR thermal residue surface decreased and the Ca/PO4 mass percent increased. X-ray diffraction (XRD) pattern analysis indicated that the main fraction of enclosed/bound materials on ASR residue included Ca/PO4- associated crystalline complexes, and that immobile Ca/PO4 salts remarkably inhibited the desorption of heavy metals from ASR residues. These results support the potential use of nanometallic Ca/CaO/PO4 as a simple, suitable and highly efficient material for the gentle immobilization of heavy metals in hazardous ASR thermal residue in dry condition.

  20. Recovery of precious metals from low-grade automobile shredder residue: A novel approach for the recovery of nanozero-valent copper particles.

    PubMed

    Singh, Jiwan; Lee, Byeong-Kyu

    2016-02-01

    The presence of precious metals (PMs) in low-grade automobile shredder residue (ASR) makes it attractive for recycling. This study investigated the leaching and recovery characteristics of two PMs (Cu and Ag) and two heavy metals (Mn and Co) from ASR. The effects of H2O2, leaching temperature, liquid to solid (L/S) ratio, and particle size on metal leaching were determined in an aqueous solution of 0.5M nitric acid. The metal leaching rate was increased with increasing nitric acid concentration, amount of H2O2, L/S ratio and temperature. The leaching kinetics was analyzed by using a second-order reaction model. In the analysis of leaching kinetics, the metal leaching data were well fitted (R(2)⩾0.99) with the second-order reaction model. The activation energy (kJ/mol) for metal leaching was 39.6 for Cu, 17.1 for Ag, 17.3 for Mn and 29.2 for Co. Metal recovery was carried out by fractional precipitation with the addition of advanced Fenton's regent. Metal recovery efficiency was increased to 99.95% for Cu, 99.8% for Mn, 90.0% for Ag and 96.46% for Co with the advanced Fenton's regent. In particular, a novel finding of the PM recovery is that Cu can also be recovered directly from the leachate of ASR in the form of zero-valent copper (ZVC) nanoparticles (NPs). Hydrometallurgical recovery of the metals from ASR using nitric acid is highly efficient.

  1. Effects of a triazole fungicide and a pyrethroid insecticide on the decomposition of leaves in the presence or absence of macroinvertebrate shredders.

    PubMed

    Rasmussen, Jes Jessen; Monberg, Rikke Juul; Baattrup-Pedersen, Annette; Cedergreen, Nina; Wiberg-Larsen, Peter; Strobel, Bjarne; Kronvang, Brian

    2012-08-15

    Previously, laboratory experiments have revealed that freely diluted azole fungicides potentiate the direct toxic effect of pyrethroid insecticides on Daphnia magna. More ecologically relevant exposure scenarios where pesticides are adsorbed have not been addressed. In this study we exposed beech leaves (Fagus sylvatica) to the azole fungicide propiconazole (50 or 500 μg L(-1)), the pyrethroid insecticide alpha-cypermethrin (0.1 or 1 μg L(-1)) or any combination of the two for 3h. Exposed leaves were transferred to aquaria with or without an assemblage of macroinvertebrate shredders, and we studied treatment effects on rates of microbial leaf decomposition, microbial biomass (using C:N ratio as a surrogate measure) and macroinvertebrate shredding activity during 26 days post-exposure. Microbial leaf decomposition rates were significantly reduced in the propiconazole treatments, and the reduction in microbial activity was significantly correlated with loss of microbial biomass (increased C:N ratio). Macroinvertebrate shredding activity was significantly reduced in the alpha-cypermethrin treatments. In addition, the macroinvertebrate assemblage responded to the propiconazole treatments by increasing their consumption of leaf litter with lower microbial biomass, probably to compensate for the reduced nutritional quality of this leaf litter. We found no interaction between the two pesticides on macroinvertebrate shredding activity, using Independent Action as a reference model. In terms of microbial leaf decomposition rates, however, alpha-cypermethrin acted as an antagonist on propiconazole. Based on these results we emphasise the importance of considering indirect effects of pesticides in the risk assessment of surface water ecosystems.

  2. Quantitative analysis and reduction of the eco-toxicity risk of heavy metals for the fine fraction of automobile shredder residue (ASR) using H2O2.

    PubMed

    Singh, Jiwan; Yang, Jae-Kyu; Chang, Yoon-Young

    2016-02-01

    Automobile shredder residue (ASR) fraction (size <0.25mm) can be considered as hazardous due to presence of high concentrations of heavy metals. Hydrogen peroxide combined with nitric acid has been used for the recovery of heavy metals (Zn, Cu, Mn, Fe, Ni, Pb, Cd and Cr) from the fine fraction of ASR. A sequential extraction procedure has also been used to determine the heavy metal speciation in the fine fraction of ASR before and after treatment. A risk analysis of the fine fraction of ASR before and after treatment was conducted to assess the bioavailability and eco-toxicity of heavy metals. These results showed that the recovery of heavy metals from ASR increased with an increase in the hydrogen peroxide concentration. A high concentration of heavy metals was found to be present in Cbio fractions (the sum of the exchangeable and carbonate fractions) in the fine fraction of ASR, indicating high toxicity risk. The Cbio rate of all selected heavy metals was found to range from 8.6% to 33.4% of the total metal content in the fine fraction of ASR. After treatment, Cbio was reduced to 0.3-3.3% of total metal upon a treatment with 2.0% hydrogen peroxide. On the basis of the risk assessment code (RAC), the environmental risk values for heavy metals in the fine fraction of ASR reflect high risk/medium risk. However, after treatment, the heavy metals would be categorized as low risk/no risk. The present study concludes that hydrogen peroxide combined with nitric acid is a promising treatment for the recovery and reduction of the eco-toxicity risk of heavy metals in ASR.

  3. Destruction and formation of PCDD/Fs in a fluidised bed combustor co-incinerating automotive shredder residue with refuse derived fuel and wastewater treatment sludge.

    PubMed

    Van Caneghem, J; Vermeulen, I; Block, C; Van Brecht, A; Van Royen, P; Jaspers, M; Wauters, G; Vandecasteele, C

    2012-03-15

    During an eight day trial automotive shredder residue (ASR) was added to the usual waste feed of a Fluidized Bed Combustor (FBC) for waste-to-energy conversion; the input waste mix consisted of 25% ASR, 25% refuse-derived fuel (RDF) and 50% wastewater treatment (WWT) sludge. All inputs and outputs were sampled and the concentration of the 17 PCDD/Fs with TEF-values was determined in order to obtain "PCDD/F fingerprints". The ASR contained approximately 9000 ng PCDD/Fs/kg(DW), six times more than the RDF and 10 times more than the WWT sludge. The fingerprint of ASR and RDF was dominated by HpCDD and OCDD, which accounted for 90% of the total PDDD/F content, whereas the WWT sludge contained relatively more HpCDFs and OCDF (together 70%). The flue gas cleaning residue (FGCR) and fly and boiler ash contained approximately 30,000 and 2500 ng PCDD/Fs/kg(DW), respectively. The fingerprints of these outputs were also dominated by HpCDFs and OCDF. The bottom ash contained only OCDD and OCDF, in total 8 ng PCDD/Fs/kg (DW). From the comparison of the bottom ash fingerprints with the fingerprints of the other output fractions and of the inputs, it could be concluded that the PCDD/Fs in the waste were destroyed and new PCDD/Fs were formed in the post combustion process by de novo synthesis. During the ASR-co-incineration, the PCDD/F congener concentrations in the fly and boiler ash, FGCR and flue gas were 1.25-10 times higher compared to the same output fractions generated during incineration of the usual waste mix (70% RDF and 30% WWT sludge). The concentration of the higher chlorinated PCDD/Fs increased most. As these congeners have the lowest TEF-factors, the total PCDD/F output, expressed in kg TEQ/year, of the FBC did not increase significantly when ASR was co-incinerated. Due to the relatively high copper levels in the ASR, the copper concentrations in the FBCs outputs increased. As copper catalysis the de novo syntheses, this could explain the increase in PCDD

  4. Polybrominated dibenzo-p-dioxins/dibenzofurans and polybrominated diphenyl ethers in soil, vegetation, workshop-floor dust, and electronic shredder residue from an electronic waste recycling facility and in soils from a chemical industrial complex in eastern China

    SciTech Connect

    Jing Ma; Rudolf Addink; Sehun Yun; Jinping Cheng; Wenhua Wang; Kurunthachalam Kannan

    2009-10-01

    In this study, 11 2,3,7,8-substituted PBDD/Fs and 10 polybrominated diphenyl ether (PBDE) congeners were determined in electronic shredder waste, workshop-floor dust, soil, and leaves (of plants on the grounds of the facility) from a large-scale electronic wastes (e-waste) recycling facility and in surface soil from a chemical-industrial complex (comprising a coke-oven plant, a coal-fired power plant, and a chlor-alkali plant) as well as agricultural areas in eastern China. Total PBDD/F concentrations in environmental samples were in the range of 113-818 pg/g dry wt (dw) for leaves, 392-18,500 pg/g dw for electronic shredder residues, 716-80,0000 pg/g dw for soil samples, and 89,600-14,3000 pg/g dw for workshop-floor dust from the e-waste recycling facility and in a range from nondetect (ND) to 427 pg/g dw in soil from the chemical-industrial complex. The highest mean concentrations of total PBDD/Fs were found in soil samples and workshop-floor dust from the e-waste recycling facility. The dioxin-like toxic equivalent (measured as TEQ) concentrations of PBDD/Fs were greater than the TEQs of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) reported in our previous study for the same set of samples. The concentrations of PBDFs were several orders of magnitude higher than the concentrations of PBDDs in samples from the e-waste facility or from soil from the chemical-industrial complex. A significant correlation was found between the concentrations of {Sigma}PBDD/Fs and {Sigma}PBDEs (r = 0.769, p < 0.01) and between SPBDD/Fs and the previously reported SPCDD/F concentrations (r = 0.805, p < 0.01). The estimated daily human intakes of TEQs contributed by PBDD/Fs via soil/dust ingestion and dermal exposures in e-waste recycling facilities were higher than the intakes of TEQs contributed by PCDD/Fs, calculated in our previous study. 45 refs., 2 figs., 2 tabs.

  5. Viability study of automobile shredder residue as fuel.

    PubMed

    Edo, Mar; Aracil, Ignacio; Font, Rafael; Anzano, Manuela; Fullana, Andrés; Collina, Elena

    2013-09-15

    Car Fluff samples collected from a shredding plant in Italy were classified based on particle size, and three different size fractions were obtained in this way. A comparison between these size fractions and the original light fluff was made from two different points of view: (i) the properties of each size fraction as a fuel were evaluated and (ii) the pollutants evolved when each size fraction was subjected to combustion were studied. The aim was to establish which size fraction would be the most suitable for the purposes of energy recovery. The light fluff analyzed contained up to 50 wt.% fines (particle size<20 mm). However, its low calorific value and high emissions of polychlorinated dioxins and furans (PCDD/Fs), generated during combustion, make the fines fraction inappropriate for energy recovery, and therefore, landfilling would be the best option. The 50-100 mm fraction exhibited a high calorific value and low PCDD/F emissions were generated when the sample was combusted, making it the most suitable fraction for use as refuse-derived fuel (RDF). Results obtained suggest that removing fines from the original ASR sample would lead to a material product that is more suitable for use as RDF.

  6. CHARACTERIZATION OF EMISSIONS FROM THE SIMULATED OPEN-BURNING OF NON-METALLIC AUTOMOBILE SHREDDER RESIDUE

    EPA Science Inventory

    The report gives results of a study in which the open combustion of a nonmetallic waste product called "fluff" was simulated and the resulting emissions collected and characterized to gain insight into the types and quantities of these air pollutants. (NOTE: The reclamation proce...

  7. Hospital waste shredder test series at the DONLEE Pilot Test Facility

    SciTech Connect

    Hoffman, Robert; Sak, James

    1992-09-01

    This report describes the coal firing and coal and noninfectious hospital waste co-firing testing and emissions rates for the tests conducted at the DONLEE pilot plant facility during mid-December 1991 through early March 1992. The emissions obtained during these tests are in turn used to predict the emission rates for the proof-of-concept facility that is to be built at the Lebanon Veterans Affairs Medical Center. In addition, the reliability and performance of the waste shredding/feeding system were evaluated from this testing.

  8. Hospital waste shredder test series at the DONLEE Pilot Test Facility. Final report

    SciTech Connect

    Not Available

    1992-09-01

    This report describes the coal firing and coal and noninfectious hospital waste co-firing testing and emissions rates for the tests conducted at the DONLEE pilot plant facility during mid-December 1991 through early March 1992. The emissions obtained during these tests are in turn used to predict the emission rates for the proof-of-concept facility that is to be built at the Lebanon Veterans Affairs Medical Center. In addition, the reliability and performance of the waste shredding/feeding system were evaluated from this testing.

  9. Document security: a funny thing happened on the way to the shredder.

    PubMed

    McConnell, Charles R

    2003-01-01

    In these days of close attention to security of information handled electronically, there is a tendency to overlook the security of hard-copy documents, particularly patient records and employee documentation. Document security is related to growing concerns for individual privacy; guidelines are furnished for protecting employee privacy by separating retention practices for business information from personal information. Sensitive documentation requires rules and procedures for processing, retaining, accessing, storing and eventually destroying. Also, documents that are missing or incomplete sometimes present unique problems for the organization. The article provides simple rules for safeguarding employee and patient documentation. PMID:12785555

  10. An updated look at document security: from initiation to storage or shredder.

    PubMed

    McConnell, Charles R

    2014-01-01

    In these days of close attention to security of information handled electronically, there is often a tendency to overlook the security of hard-copy documents. Document security can involve many areas of business, but the health care department manager's concerns are primarily for patient records and employee documentation. Document security is closely related to growing concerns for individual privacy; guidelines are furnished for protecting employee privacy by separating retention practices for business information from personal information. Sensitive documentation requires rules and procedures for processing, retaining, accessing, storing, and eventually destroying. Also, documents that are missing or incomplete at times present unique problems for the organization. The department manager is provided with some simple rules for safeguarding employee and patient documentation. PMID:25350025

  11. An updated look at document security: from initiation to storage or shredder.

    PubMed

    McConnell, Charles R

    2014-01-01

    In these days of close attention to security of information handled electronically, there is often a tendency to overlook the security of hard-copy documents. Document security can involve many areas of business, but the health care department manager's concerns are primarily for patient records and employee documentation. Document security is closely related to growing concerns for individual privacy; guidelines are furnished for protecting employee privacy by separating retention practices for business information from personal information. Sensitive documentation requires rules and procedures for processing, retaining, accessing, storing, and eventually destroying. Also, documents that are missing or incomplete at times present unique problems for the organization. The department manager is provided with some simple rules for safeguarding employee and patient documentation.

  12. Modelling of post-fragmentation waste stream processing within UK shredder facilities.

    PubMed

    Coates, Gareth; Rahimifard, Shahin

    2009-01-01

    With the introduction of producer responsibility legislation within the UK (i.e., waste electrical and electronic equipment directive and end-of-life vehicles directive), specific recycling and recovery targets have been imposed to improve the sustainability of end-of-life products. With the introduction of these targets, and the increased investment in post-fragmentation facilities, automated material separation technologies are playing an integral role within the UK's end-of-life waste management strategy. Post-fragmentation facilities utilise a range of purification technologies that target certain material attributes (e.g., density, magnetism, volume) to isolate materials from the shredded waste stream. High ferrous prices have historically meant that UK facilities have been primarily interested in recovering iron and steel, establishing processing routes that are very effective at removing these material types, but as a consequence are extremely rigid and inflexible. With the proliferation of more exotic materials within end-of-life products, combined with more stringent recycling targets, there is therefore a need to optimise the current waste reclamation processes to better realise effort-to-value returns. This paper provides a background as to the current post-fragmentation processing adopted within the UK, and describes the development of a post-fragmentation modelling approach, capable of simulating the value-added processing that a piece of automated separation equipment can have on a fragmented waste stream. These include the modelling of the inefficiencies of the technology, the effects of material entanglement on separation, determination of typical material sizing and an appreciation for compositional value. The implementation of this approach within a software decision-support system is described, before the limitations, calibration and further validation of the approach are discussed. PMID:18472415

  13. Production and evaluation of Ighu from selected cassava varieties using a motorized shredder-a response surface analysis.

    PubMed

    Iwe, Madu O; Agiriga, Ann N

    2013-11-01

    Cassava varieties, TME419, TMS30572, and TMS98/0505, were planted and harvested at 3-month intervals of 10, 13, and 16 months, respectively. A central composite response surface design was used to study the effects of the variables cassava variety, harvesting time, and shredding aperture on selected physicochemical properties of Ighu samples. Regression models showed that the experimental variables had significant (P ≤ 0.05) effects on the hydrogen cyanide, moisture content, thickness, and width of dry Ighu. Minimum values obtainable for the physicochemical properties were 8.1195 mg/kg (10-month, 3-mm shredding aperture from TMS98/0505), 7.58% (13-month, 3-mm shredding aperture from TME419), 0.19 mm (13-month, 3-mm shredding aperture and from TMS30572), and 0.99 mm (16-month, 3-mm shredding aperture from TME419) for hydrogen cyanide, moisture content, thickness, and width, respectively. In addition, Ighu produced from 3-mm shredding aperture (TMS30572) at 10-month harvest was the most preferred of all the samples.

  14. Grazers, shredders and filtering carnivores – The evolution of feeding ecology in Drusinae (Trichoptera: Limnephilidae): insights from a molecular phylogeny

    PubMed Central

    Pauls, Steffen U.; Graf, Wolfram; Haase, Peter; Lumbsch, H. Thorsten; Waringer, Johann

    2016-01-01

    We examined the phylogenetic relationships between species and genera within the caddisfly subfamily Drusinae (Trichoptera: Limnephilidae) using sequence data from two mitochondrial loci (cytochrome oxidase 1, large subunit rRNA) and one nuclear gene (wingless). Sequence data were analysed for 28 species from five genera from the subfamily. We analysed individual and combined data sets using a Bayesian Markov Chain Monte Carlo and a Maximum Parsimony approach and compared the performance of each partition for resolving phylogenetic relationships at this level. In terms of resolution and phylogenetic utility wingless outperformed the two mitochondrial gene partitions. Using both Shimodaira-Hasegawa and expected likelihood weights tests we tested several hypotheses of relationships previously inferred based on adult morphological characters. The data did not support the generic concept, or many previously proposed species groupings, based on adult morphology. In contrast, the molecular data correlated with the morphology and feeding ecology of larvae. Using Bayesian ancestral character state reconstructions we inferred the evolution of feeding ecology and relevant larval morphological characters. Our analyses showed that within the subfamily Drusinae two derived feeding types evolved. One of these – grazing epilithic algae – is otherwise unusual in the Limnephilidae and may have promoted the high degree of diversity in the Drusinae. PMID:18171625

  15. [Testing and commercialization of a cotton stalk shredder and plow]. Technical progress report, July--September, 1995

    SciTech Connect

    Thacker, G.W.

    1995-10-23

    The paper describes plans to field test several prototypes of plows that cut cotton stalks after harvesting and plows then back into the soil to prepare the field for the next planting. Modifications to the design have been made to allow the soil to more easily slide off the plow to reduce fuel consumption. A prototype has been shipped to Australia for testing in their fields and further product development. A farm machinery manufacturer has been selected to build two full-scale preproduction prototypes. Field testing will be done at sites in California and Arizona, since both have regulations specifying that cotton stalks must be shredded.

  16. Effects of current-use fungicides and their mixtures on the feeding and survival of the key shredder Gammarus fossarum.

    PubMed

    Zubrod, J P; Baudy, P; Schulz, R; Bundschuh, M

    2014-05-01

    Fungicides are frequently applied in agriculture and are subsequently detected in surface waters in total concentrations of up to several tens of micrograms per liter. These concentrations imply potential effects on aquatic communities and fundamental ecosystem functions such as leaf litter breakdown. In this context, the present study investigates sublethal and lethal effects of organic (azoxystrobin, carbendazim, cyprodinil, quinoxyfen, and tebuconazole) and inorganic (three copper (Cu)-based substances and sulfur) current-use fungicides and their mixtures on the key leaf-shredding invertebrate Gammarus fossarum. The feeding activity of fungicide-exposed gammarids was quantified as sublethal endpoint using a static (organic fungicides; 7 d test duration) or a semi-static (inorganic fungicides; 6 d test duration with a water exchange after 3 d) approach (n=30). EC50-values of organic fungicides were generally observed at concentrations resulting in less than 20% mortality, with the exception of carbendazim. With regard to feeding, quinoxyfen was the most toxic organic fungicide, followed by cyprodinil, carbendazim, azoxystrobin, and tebuconazole. Although all tested organic fungicides have dissimilar (intended) modes of action, a mixture experiment revealed a synergistic effect on gammarids' feeding at high concentrations when using "independent action" as the reference model (∼35% deviation between predicted and observed effect). This may be explained by the presence of a synergizing azole fungicide (i.e. tebuconazole) in this mixture. Furthermore, lethal concentrations of all Cu-based fungicides assessed in this study were comparable amongst one another. However, they differed markedly in their effective concentrations when using feeding activity as the endpoint, with Cu-sulfate being most toxic, followed by Cu-hydroxide and Cu-octanoate. In contrast, sulfur neither affected survival nor the feeding activity of gammarids (up to ∼5 mg/L) but reduced Cu-sulfate's toxicity when applied in a binary mixture. Sulfur-related metabolic processes which reduce the physiological availability of Cu may explain this antagonistic effect. For both fungicide mixtures, the present study thus uncovered deviations from the appropriate reference model, while ecotoxicological effects were observed at field relevant (total) fungicide concentrations. Additionally, for more than half of the tested single substances, a potential risk for Gammarus and thus for the ecological function mediated by these organisms was evident at concentrations measured in agriculturally influenced surface waters. These results suggest that risks to the fundamental ecosystem function of leaf litter breakdown posed by fungicides may not be adequately considered during the regulation of these compounds, which makes further experimental efforts necessary. PMID:24674876

  17. Is the diet of a typical shredder related to the physical habitat of headwater streams in the Brazilian Cerrado?

    EPA Science Inventory

    Macroinvertebrates are important for processing leaf detritus in temperate streams, but studies about their role in tropical streams are scarce and often present conflicting results. We assessed the diet of Phylloicus (Trichoptera: Calamoceratidae) larvae, that is generally class...

  18. [Testing and commercialization of a cotton stalk shredder and plow]. Technical progress report, October--December 1995

    SciTech Connect

    Thacker, G.W.

    1996-01-27

    This quarterly report describes work on Task 1: Field test and sell prototype to Ellis Equipment, Ltd; Task 2: Design, build, and field test two prototypes; and Task 3: Produce and sell Pegasus to farmers. The equipment has been built to shred stalks, deeply till the soil, and prepare seedbeds for cotton plants. The equipment has been field tested in Australia and is currently being field tested in California and Arizona. Unexpected problems appeared with hard dry soils and this report describes improvements made.

  19. Automotive shredder residue (ASR): reviewing its production from end-of-life vehicles (ELVs) and its recycling, energy or chemicals' valorisation.

    PubMed

    Vermeulen, I; Van Caneghem, J; Block, C; Baeyens, J; Vandecasteele, C

    2011-06-15

    ASR is in Europe classified as hazardous waste. Both the stringent landfill legislation and the objectives/legislation related to ELV treatment of various countries, will limit current landfilling practice and impose an increased efficiency of the recovery and recycling of ELVs. The present paper situates ASR within the ELV context. Primary recovery techniques recycle up to 75% of the ELV components; the remaining 25% is called ASR. Characteristics of ASR and possible upgrading by secondary recovery techniques are reviewed. The latter techniques can produce a fuel- or fillergrade ASR, however with limitations as discussed. A further reduction of ASR to be disposed of calls upon (co-)incineration or the use of thermo-chemical processes, such as pyrolysis or gasification. The application in waste-to-energy plants, in cement kilns or in metallurgical processes is possible, with attention to the possible environmental impact: research into these impacts is discussed in detail. Pyrolysis and gasification are emerging technologies: although the sole use of ASR is debatable, its mixing with other waste streams is gradually being applied in commercial processes. The environmental impacts of the processes are acceptable, but more supporting data are needed and the advantage over (co-)incineration remains to be proven. PMID:21440364

  20. Automotive shredder residue (ASR): reviewing its production from end-of-life vehicles (ELVs) and its recycling, energy or chemicals' valorisation.

    PubMed

    Vermeulen, I; Van Caneghem, J; Block, C; Baeyens, J; Vandecasteele, C

    2011-06-15

    ASR is in Europe classified as hazardous waste. Both the stringent landfill legislation and the objectives/legislation related to ELV treatment of various countries, will limit current landfilling practice and impose an increased efficiency of the recovery and recycling of ELVs. The present paper situates ASR within the ELV context. Primary recovery techniques recycle up to 75% of the ELV components; the remaining 25% is called ASR. Characteristics of ASR and possible upgrading by secondary recovery techniques are reviewed. The latter techniques can produce a fuel- or fillergrade ASR, however with limitations as discussed. A further reduction of ASR to be disposed of calls upon (co-)incineration or the use of thermo-chemical processes, such as pyrolysis or gasification. The application in waste-to-energy plants, in cement kilns or in metallurgical processes is possible, with attention to the possible environmental impact: research into these impacts is discussed in detail. Pyrolysis and gasification are emerging technologies: although the sole use of ASR is debatable, its mixing with other waste streams is gradually being applied in commercial processes. The environmental impacts of the processes are acceptable, but more supporting data are needed and the advantage over (co-)incineration remains to be proven.

  1. Distribution of detritivores in tropical forest streams of peninsular Malaysia: role of temperature, canopy cover and altitude variability.

    PubMed

    Che Salmah, Md Rawi; Al-Shami, Salman Abdo; Abu Hassan, Ahmad; Madrus, Madziatul Rosemahanie; Nurul Huda, Abdul

    2014-07-01

    The diversity and abundance of macroinvertebrate shredders were investigated in 52 forested streams (local scale) from nine catchments (regional scale) covering a large area of peninsular Malaysia. A total of 10,642 individuals of aquatic macroinvertebrates were collected, of which 18.22% were shredders. Biodiversity of shredders was described by alpha (αaverage), beta (β) and gamma diversity (γ) measures. We found high diversity and abundance of shredders in all catchments, represented by 1,939 individuals (range 6-115 and average per site of 37.29±3.48 SE) from 31 taxa with 2-13 taxa per site (αaverage=6.98±0.33 SE) and 10-15 taxa per catchment (γ=13.33±0.55 SE). At the local scale, water temperature, stream width, depth and altitude were correlated significantly with diversity (Adj-R2=0.205). Meanwhile, dissolved oxygen, stream velocity, water temperature, stream width and altitude were correlated to shredder abundance (Adj-R2=0.242). At regional scale, however, water temperature was correlated negatively with β and γ diversity (r2=0.161 and 0.237, respectively) as well as abundance of shredders (r2=0.235). Canopy cover was correlated positively with β diversity (r2=0.378) and abundance (r2=0.266), meanwhile altitude was correlated positively with β (quadratic: r2=0.175), γ diversity (quadratic: r2=0.848) as well as abundance (quadratic: r2=0.299). The present study is considered as the first report describing the biodiversity and abundance of shredders in forested headwater streams across a large spatial scale in peninsular Malaysia. We concluded that water temperature has a negative effect while altitude showed a positive relationship with diversity and abundance of shredders. However, it was difficult to detect an influence of canopy cover on shredder diversity. PMID:23483291

  2. Distribution of detritivores in tropical forest streams of peninsular Malaysia: role of temperature, canopy cover and altitude variability

    NASA Astrophysics Data System (ADS)

    Che Salmah, Md Rawi; Al-Shami, Salman Abdo; Abu Hassan, Ahmad; Madrus, Madziatul Rosemahanie; Nurul Huda, Abdul

    2014-07-01

    The diversity and abundance of macroinvertebrate shredders were investigated in 52 forested streams (local scale) from nine catchments (regional scale) covering a large area of peninsular Malaysia. A total of 10,642 individuals of aquatic macroinvertebrates were collected, of which 18.22 % were shredders. Biodiversity of shredders was described by alpha (αaverage ), beta (β) and gamma diversity (γ) measures. We found high diversity and abundance of shredders in all catchments, represented by 1,939 individuals (range 6-115 and average per site of 37.29 ± 3.48 SE) from 31 taxa with 2-13 taxa per site (αaverage = 6.98 ± 0.33 SE) and 10-15 taxa per catchment (γ = 13.33 ± 0.55 SE). At the local scale, water temperature, stream width, depth and altitude were correlated significantly with diversity (Adj- R 2 = 0.205). Meanwhile, dissolved oxygen, stream velocity, water temperature, stream width and altitude were correlated to shredder abundance (Adj- R 2 = 0.242). At regional scale, however, water temperature was correlated negatively with β and γ diversity ( r 2 = 0.161 and 0.237, respectively) as well as abundance of shredders ( r 2 = 0.235). Canopy cover was correlated positively with β diversity ( r 2 = 0.378) and abundance ( r 2 = 0.266), meanwhile altitude was correlated positively with β (quadratic: r 2 = 0.175), γ diversity (quadratic: r 2 = 0.848) as well as abundance (quadratic: r 2 = 0.299). The present study is considered as the first report describing the biodiversity and abundance of shredders in forested headwater streams across a large spatial scale in peninsular Malaysia. We concluded that water temperature has a negative effect while altitude showed a positive relationship with diversity and abundance of shredders. However, it was difficult to detect an influence of canopy cover on shredder diversity.

  3. Distribution of detritivores in tropical forest streams of peninsular Malaysia: role of temperature, canopy cover and altitude variability

    NASA Astrophysics Data System (ADS)

    Che Salmah, Md Rawi; Al-Shami, Salman Abdo; Abu Hassan, Ahmad; Madrus, Madziatul Rosemahanie; Nurul Huda, Abdul

    2013-03-01

    The diversity and abundance of macroinvertebrate shredders were investigated in 52 forested streams (local scale) from nine catchments (regional scale) covering a large area of peninsular Malaysia. A total of 10,642 individuals of aquatic macroinvertebrates were collected, of which 18.22 % were shredders. Biodiversity of shredders was described by alpha (αaverage ), beta (β) and gamma diversity (γ) measures. We found high diversity and abundance of shredders in all catchments, represented by 1,939 individuals (range 6-115 and average per site of 37.29 ± 3.48 SE) from 31 taxa with 2-13 taxa per site (αaverage = 6.98 ± 0.33 SE) and 10-15 taxa per catchment (γ = 13.33 ± 0.55 SE). At the local scale, water temperature, stream width, depth and altitude were correlated significantly with diversity (Adj-R 2 = 0.205). Meanwhile, dissolved oxygen, stream velocity, water temperature, stream width and altitude were correlated to shredder abundance (Adj-R 2 = 0.242). At regional scale, however, water temperature was correlated negatively with β and γ diversity (r 2 = 0.161 and 0.237, respectively) as well as abundance of shredders (r 2 = 0.235). Canopy cover was correlated positively with β diversity (r 2 = 0.378) and abundance (r 2 = 0.266), meanwhile altitude was correlated positively with β (quadratic: r 2 = 0.175), γ diversity (quadratic: r 2 = 0.848) as well as abundance (quadratic: r 2 = 0.299). The present study is considered as the first report describing the biodiversity and abundance of shredders in forested headwater streams across a large spatial scale in peninsular Malaysia. We concluded that water temperature has a negative effect while altitude showed a positive relationship with diversity and abundance of shredders. However, it was difficult to detect an influence of canopy cover on shredder diversity.

  4. Distribution of detritivores in tropical forest streams of peninsular Malaysia: role of temperature, canopy cover and altitude variability.

    PubMed

    Che Salmah, Md Rawi; Al-Shami, Salman Abdo; Abu Hassan, Ahmad; Madrus, Madziatul Rosemahanie; Nurul Huda, Abdul

    2014-07-01

    The diversity and abundance of macroinvertebrate shredders were investigated in 52 forested streams (local scale) from nine catchments (regional scale) covering a large area of peninsular Malaysia. A total of 10,642 individuals of aquatic macroinvertebrates were collected, of which 18.22% were shredders. Biodiversity of shredders was described by alpha (αaverage), beta (β) and gamma diversity (γ) measures. We found high diversity and abundance of shredders in all catchments, represented by 1,939 individuals (range 6-115 and average per site of 37.29±3.48 SE) from 31 taxa with 2-13 taxa per site (αaverage=6.98±0.33 SE) and 10-15 taxa per catchment (γ=13.33±0.55 SE). At the local scale, water temperature, stream width, depth and altitude were correlated significantly with diversity (Adj-R2=0.205). Meanwhile, dissolved oxygen, stream velocity, water temperature, stream width and altitude were correlated to shredder abundance (Adj-R2=0.242). At regional scale, however, water temperature was correlated negatively with β and γ diversity (r2=0.161 and 0.237, respectively) as well as abundance of shredders (r2=0.235). Canopy cover was correlated positively with β diversity (r2=0.378) and abundance (r2=0.266), meanwhile altitude was correlated positively with β (quadratic: r2=0.175), γ diversity (quadratic: r2=0.848) as well as abundance (quadratic: r2=0.299). The present study is considered as the first report describing the biodiversity and abundance of shredders in forested headwater streams across a large spatial scale in peninsular Malaysia. We concluded that water temperature has a negative effect while altitude showed a positive relationship with diversity and abundance of shredders. However, it was difficult to detect an influence of canopy cover on shredder diversity.

  5. Recycling scheme for scrapped automobiles in Japan

    SciTech Connect

    Suzuki, Masao; Nakajima, Akira; Taya, Sadao

    1995-12-31

    Over 5 million cars are scrapped yearly in Japan. After dismantling scrapped automobiles, they are put into a shredder for differential recovery of ferrous and nonferrous metals. The residue, which is called shredder dust, runs over 1.2 million tons per year. This paper reports a entire sequence of scrapping cars in Japan with the following sections: (1) production and scrapped car management, (2) material composition, (3) dismantling, (4) shredder plant, (5) differential recovery of metals including specific gravity and newly developed color separation.

  6. Technology Manners for the 21st Century.

    ERIC Educational Resources Information Center

    Ekhaml, Leticia

    1998-01-01

    Discusses etiquette for today's technology, including paper copiers; desktop or laptop computers; fax machines; answering machines and voice mail; printers; cellular phones, pagers, and beepers; telephones; videotapes, videodisks, and CD-ROMs; paper shredders; Internet use; and magnetic boards. (LRW)

  7. Stream ecosystem integrity is impaired by logging and shifting agriculture in a global megadiversity center (Sarawak, Borneo).

    PubMed

    Jinggut, Tajang; Yule, Catherine M; Boyero, Luz

    2012-10-15

    In common with most of Borneo, the Bakun region of Sarawak is currently subject to heavy deforestation mainly due to logging and, to a lesser extent, traditional slash-and-burn farming practices. This has the potential to affect stream ecosystems, which are integrators of environmental change in the surrounding terrestrial landscape. This study evaluated the effects of both types of deforestation by using functional and structural indicators (leaf litter decomposition rates and associated detritivores or 'shredders', respectively) to compare a fundamental ecosystem process, leaf litter decomposition, within logged, farmed and pristine streams. Slash-and-burn agricultural practices increased the overall rate of decomposition despite a decrease in shredder species richness (but not shredder abundance) due to increased microbial decomposition. In contrast, decomposition by microbes and invertebrates was slowed down in the logged streams, where shredders were less abundant and less species rich. This study suggests that shredder communities are less affected by traditional agricultural farming practices, while modern mechanized deforestation has an adverse effect on both shredder communities and leaf breakdown. PMID:22922133

  8. Infectious waste feed system

    DOEpatents

    Coulthard, E. James

    1994-01-01

    An infectious waste feed system for comminuting infectious waste and feeding the comminuted waste to a combustor automatically without the need for human intervention. The system includes a receptacle for accepting waste materials. Preferably, the receptacle includes a first and second compartment and a means for sealing the first and second compartments from the atmosphere. A shredder is disposed to comminute waste materials accepted in the receptacle to a predetermined size. A trough is disposed to receive the comminuted waste materials from the shredder. A feeding means is disposed within the trough and is movable in a first and second direction for feeding the comminuted waste materials to a combustor.

  9. 7 CFR 58.318 - Butter, frozen or plastic cream melting machines.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Butter, frozen or plastic cream melting machines. 58... Service 1 Equipment and Utensils § 58.318 Butter, frozen or plastic cream melting machines. Shavers, shredders or melting machines used for rapid melting of butter, frozen or plastic cream shall be...

  10. 7 CFR 58.318 - Butter, frozen or plastic cream melting machines.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Butter, frozen or plastic cream melting machines. 58... Service 1 Equipment and Utensils § 58.318 Butter, frozen or plastic cream melting machines. Shavers, shredders or melting machines used for rapid melting of butter, frozen or plastic cream shall be...

  11. 7 CFR 58.318 - Butter, frozen or plastic cream melting machines.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Butter, frozen or plastic cream melting machines. 58... Service 1 Equipment and Utensils § 58.318 Butter, frozen or plastic cream melting machines. Shavers, shredders or melting machines used for rapid melting of butter, frozen or plastic cream shall be...

  12. 7 CFR 58.318 - Butter, frozen or plastic cream melting machines.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Butter, frozen or plastic cream melting machines. 58... Service 1 Equipment and Utensils § 58.318 Butter, frozen or plastic cream melting machines. Shavers, shredders or melting machines used for rapid melting of butter, frozen or plastic cream shall be...

  13. 7 CFR 58.318 - Butter, frozen or plastic cream melting machines.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Butter, frozen or plastic cream melting machines. 58... Service 1 Equipment and Utensils § 58.318 Butter, frozen or plastic cream melting machines. Shavers, shredders or melting machines used for rapid melting of butter, frozen or plastic cream shall be...

  14. 40 CFR Appendix A to Subpart Rrr... - General Provisions Applicability to Subpart RRR

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants for Secondary Aluminum... Applicability Determination Yes EPA retains approval authority. § 63.1(c)(1) Applicability After Standard...-minute averages for an aluminum scrap shredder. § 63.8(g)(3)-(5) Yes. § 63.9(a) Notification...

  15. 40 CFR Table 3 to Subpart Rrr of... - Summary of Monitoring Requirements for New and Existing Affected Sources and Emission Units

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Pollutants for Secondary Aluminum Production Pt. 63, Subpt. RRR, Table 3 Table 3 to Subpart RRR of Part 63... legible. Aluminum scrap shredder with fabric filter Bag leak detector or Install and operate in accordance... or Design and install in accordance with PS-1; collect data in accordance with subpart A of 40...

  16. 40 CFR Appendix A to Subpart Rrr... - General Provisions Applicability to Subpart RRR

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants for Secondary Aluminum... Applicability Determination Yes EPA retains approval authority. § 63.1(c)(1) Applicability After Standard...-minute averages for an aluminum scrap shredder. § 63.8(g)(3)-(5) Yes. § 63.9(a) Notification...

  17. Argonne National Laboratory's Recycling Pilot Plant

    ScienceCinema

    Spangenberger, Jeff; Jody, Sam

    2016-07-12

    Argonne has a Recycling Pilot Plant designed to save the non-metal portions of junked cars. Here, program managers demonstrate how plastic shredder residue can be recycled. (Currently these automotive leftovers are sent to landfills.) For more information, visit Argonne's Transportation Technology R&D Center Web site at http://www.transportation.anl.gov.

  18. Argonne National Laboratory's Recycling Pilot Plant

    SciTech Connect

    Spangenberger, Jeff; Jody, Sam

    2009-01-01

    Argonne has a Recycling Pilot Plant designed to save the non-metal portions of junked cars. Here, program managers demonstrate how plastic shredder residue can be recycled. (Currently these automotive leftovers are sent to landfills.) For more information, visit Argonne's Transportation Technology R&D Center Web site at http://www.transportation.anl.gov.

  19. Invertebrate grazers affect metal/metalloid fixation during litter decomposition.

    PubMed

    Schaller, Jörg; Brackhage, Carsten

    2015-01-01

    Plant litter and organic sediments are main sinks for metals and metalloids in aquatic ecosystems. The effect of invertebrates as key species in aquatic litter decomposition on metal/metalloid fixation by organic matter is described only for shredders, but for grazers as another important animal group less is known. Consequently, a laboratory batch experiment was conducted to examine the effect of invertebrate grazers (Lymnaea stagnalis L.) on metal/metalloid fixation/remobilization during aquatic litter decomposition. It could be shown that invertebrate grazers facilitate significantly the formation of smaller sizes of particulate organic matter (POM), as shown previously for invertebrate shredders. The metal/metalloid binding capacity of these smaller particles of POM is higher compared to leaf litter residuals. But element enrichment is not as high as shown previously for the effect by invertebrate shredders. Invertebrate grazers enhance also the mobilization of selected elements to the water, in the range also proven for invertebrate shredders but different for the different elements. Nonetheless invertebrate grazers activity during aquatic litter decomposition leads to a metal/metalloid fixation into leaf litter as part of sediment organic matter. Hence, the effect of invertebrate grazers on metal/metalloid fixation/remobilization contrasts partly with former assessments revealing the possibility of an enhanced metal/metalloid fixation.

  20. 40 CFR Table 2 to Subpart Rrr of... - Summary of Operating Requirements for New and Existing Affected Sources and Emission Units

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... scrap dryer/delacquering kiln/decoating kiln Labeling Identification, operating parameter ranges and... residence time requirements posted at scrap dryer/delacquering kiln/decoating kiln. Aluminum scrap shredder... material Operate using only unpainted aluminum chips. Scrap dryer/delacquering kiln/decoating kiln...

  1. Flood disturbance and predator-prey effects on regional gradients in species diversity.

    PubMed

    Mori, Terutaka; Saitoh, Takashi

    2014-01-01

    The effects of both abiotic factors and biotic interactions among guilds (i.e., inter-guild effects) have been suggested to be important for understanding spatial variation in species diversity; however, compared to the abiotic effects, the processes by which the inter-guild effects are mediated have been little described. Hence, we investigated stream invertebrate assemblages on Hokkaido Island, Japan, and assessed how the processes of determining regional patterns in species diversity differed among guilds (collector-filterers, collector-gatherers/shredders, scrapers, and predators) by taking both inter-guild and abiotic effects into consideration using Bayesian networks. Collector-gatherers/shredders, collector-filterers, and predators exhibited significant regional gradients in taxonomic richness. Gradients in the former two guilds can be generated by variation in flood disturbance regardless of interactions with other guilds. The gradient in predator taxonomic richness was indirectly related to the disturbance and was directly generated by bottom-up effects through their prey (collector-gatherers/shredders and collector-filterers). We found that not only environmental factors, but also inter-guild effects may be essential for forming the regional gradient in predators, unlike those for collector-gatherers/shredders and collector-filterers. The processes underlying the regional variation in taxonomic richness of the three guilds are interpreted in terms of the "more individuals" hypothesis, facilitation, and predator-prey relationships.

  2. 40 CFR Table 2 to Subpart Rrr of... - Summary of Operating Requirements for New and Existing Affected Sources and Emission Units

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... scrap dryer/delacquering kiln/decoating kiln Labeling Identification, operating parameter ranges and... residence time requirements posted at scrap dryer/delacquering kiln/decoating kiln. Aluminum scrap shredder... material Operate using only unpainted aluminum chips. Scrap dryer/delacquering kiln/decoating kiln...

  3. Headwater streams and forest management: does ecoregional context influence logging effects on benthic communities?

    USGS Publications Warehouse

    Medhurst, R. Bruce; Wipfli, Mark S.; Binckley, Chris; Polivka, Karl; Hessburg, Paul F.; Salter, R. Brion

    2010-01-01

    Effects of forest management on stream communities have been widely documented, but the role that climate plays in the disturbance outcomes is not understood. In order to determine whether the effect of disturbance from forest management on headwater stream communities varies by climate, we evaluated benthic macroinvertebrate communities in 24 headwater streams that differed in forest management (logged-roaded vs. unlogged-unroaded, hereafter logged and unlogged) within two ecological sub-regions (wet versus dry) within the eastern Cascade Range, Washington, USA. In both ecoregions, total macroinvertebrate density was highest at logged sites (P = 0.001) with gathering-collectors and shredders dominating. Total taxonomic richness and diversity did not differ between ecoregions or forest management types. Shredder densities were positively correlated with total deciduous and Sitka alder (Alnus sinuata) riparian cover. Further, differences in shredder density between logged and unlogged sites were greater in the wet ecoregion (logging × ecoregion interaction; P = 0.006) suggesting that differences in post-logging forest succession between ecoregions were responsible for differences in shredder abundance. Headwater stream benthic community structure was influenced by logging and regional differences in climate. Future development of ecoregional classification models at the subbasin scale, and use of functional metrics in addition to structural metrics, may allow for more accurate assessments of anthropogenic disturbances in mountainous regions where mosaics of localized differences in climate are common.

  4. 5 CFR 1312.29 - Destruction.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Room 096, OEOB between 8:00 a.m. and 4:30 p.m. Burn bags are not to be left in hallways. (2) NEOB... handed over to the authorized representative at the shredder room. Accountability records will...

  5. Conceptual process description of M division incinerator project

    SciTech Connect

    Thompson, T.K.

    1989-04-13

    This interoffice memorandum describes an incineration system to be used for incinerating wood. The system is comprised of a shredder and an incinerator. The entire process is described in detail. A brief study of particulates, carbon monoxide, carbon dioxide, and nitrogen oxides emission is presented.

  6. Effects of cadmium and resource quality on freshwater detritus processing chains: a microcosm approach with two insect species.

    PubMed

    Campos, Diana; Alves, Artur; Lemos, Marco F L; Correia, António; Soares, Amadeu M V M; Pestana, João L T

    2014-07-01

    Detritus processing is vital for freshwater ecosystems that depend on the leaf litter from riparian vegetation and is mediated by microorganisms and aquatic invertebrates. Shredder invertebrates transform coarse particulate organic matter into fine particulate organic matter used as food by collector species. Direct and indirect effects of contaminants can impair detritus processing and thus affect the functioning of these ecosystems. Here, we assessed the combined effects of a toxic metal (cadmium) and resource quality (leaf species) on detritus processing and shredder-collector interactions. We considered two types of leaves, alder and eucalyptus that were microbially conditioned under different Cd concentrations in the laboratory. The microbial communities present on leaves were analyzed by Denaturing Gradient Gel Electrophoresis (DGGE), and we also measured microbial respiration rates. Sericostoma vittatum (a caddisfly shredder) and Chironomus riparius (a midge collector) were also exposed to Cd and allowed to consume the corresponding alder or eucalyptus leaves. We evaluated C. riparius growth and leaf mass loss in multispecies microcosms. Cadmium exposure affected leaf conditioning and fungal diversity on both leaf species, as assessed by DGGE. Cadmium exposure also affected the mass loss of alder leaves by reductions in detritivore feeding, and impaired C. riparius growth. Chironomus riparius consumed alder leaf discs in the absence of shredders, but S. vittatum appear to promote C. riparius growth in treatments containing eucalyptus. These results show that indirect effects of contaminants along detritus-processing chains can occur through effects on shredder-collector interactions such as facilitation but they also depend on the nutritional quality of detritus and on sensitivity and feeding plasticity of detritivore species. PMID:24648031

  7. Riparian plant species loss alters trophic dynamics in detritus-based stream ecosystems.

    PubMed

    Lecerf, Antoine; Dobson, Michael; Dang, Christian K; Chauvet, Eric

    2005-12-01

    Riparian vegetation is closely connected to stream food webs through input of leaf detritus as a primary energy supply, and therefore, any alteration of plant diversity may influence aquatic ecosystem functioning. We measured leaf litter breakdown rate and associated biological parameters in mesh bags in eight headwater streams bordered either with mixed deciduous forest or with beech forest. The variety of leaf litter types in mixed forest results in higher food quality for large-particle invertebrate detritivores ('shredders') than in beech forest, which is dominated by a single leaf species of low quality. Breakdown rate of low quality (oak) leaf litter in coarse mesh bags was lower in beech forest streams than in mixed forest streams, a consequence of lower shredder biomass. In contrast, high quality (alder) leaf litter broke down at similar rates in both stream categories as a result of similar shredder biomass in coarse mesh bags. Microbial breakdown rate of oak and alder leaves, determined in fine mesh bags, did not differ between the stream categories. We found however aquatic hyphomycete species richness on leaf litter to positively co-vary with riparian plant species richness. Fungal species richness may enhance leaf litter breakdown rate through positive effects on resource quality for shredders. A feeding experiment established a positive relationship between fungal species richness per se and leaf litter consumption rate by an amphipod shredder (Gammarus fossarum). Our results show therefore that plant species richness may indirectly govern ecosystem functioning through complex trophic interactions. Integrating microbial diversity and trophic dynamics would considerably improve the prediction of the consequences of species loss.

  8. Thermal-nutritional regulation of functional groups in running water ecosystems. Informal technical progress report, June 1, 1983-April 30, 1984

    SciTech Connect

    Cummins, K.W.

    1984-05-01

    Three general areas were studied: validation of the macroinvertebrate functional feeding group method of stream ecosystem analysis; review of the functional feeding group method of analysis; and interaction between food quality and temperature in controlling growth within the shredder functional group. Demonstration that stream macroinvertebrate species belonging to different taxonomic groups share morphological - behavioral features relative to their modes of food acquisition is the basis of the functional feeding group separation. The macroinvertebrates in each functional group belong to functional units coupling nutritional resources with modes of feeding: resource + microorganisms + functional group. These units are: (1) Coarse particulate organic matter (CPOM) + aquatic hyphomycete fungi (and bacteria) + shredders; (2) fine particulate organic matter (FPOM) + bacteria + collectors (either filtering or gathering); (3) periphyton (attached algae and associated FPOM system) + scrapers and; (4) prey + predators. (Gougers, special wood-eating shredders, and piercers, forms that pierce individual filamentious algal cells have also been recognized.) The categorization of macroinvertebrate in functional groups finds its basis in both morpho-behavioral and physiological-biochemical similarities. Lipid (especially dietarily acquired polyunsaturated fatty acids) differences have been added to previously demonstrated differences in morphology (e.g. mandibular structure) and behavior (e.g. selection for leaf litter over FPOM by shredders). The quality of food in a given resource category and the ability (or lack of it) of the macroinvertebrates of a given functional group to select for it strongly influences growth, survival and fecundity. Shredders in particular show a high degree of selection for quality within the CPOM food resource category. 22 references, 1 figure, 2 tables.

  9. Design and operation of a remotely operated plutonium waste size reduction and material handling process

    SciTech Connect

    Stewart, III, J A; Charlesworth, D L

    1986-01-01

    Noncombustible /sup 238/Pu and /sup 239/Pu waste is generated as a result of normal operation and decommissioning activity at the Savannah River Plant, and is being retrievably stored there. As part of the long-term plant to process the stored waste and current waste for permanent disposal, a remote size reduction and material handling process is being cold-tested at Savannah River Laboratory. The process consists of a large, low-speed shredder and material handling system, a remote worktable, a bagless transfer system, and a robotically controlled manipulator. Initial testing of the shredder and material handling system and a cycle test of the bagless transfer system has been completed. Fabrication and acceptance testing of the Telerobat, a robotically controlled manipulator has been completed. Testing is scheduled to begin in 3/86. Design features maximizing the ability to remotely maintain the equipment were incorporated. Complete cold-testing of the equipment is scheduled to be completed in 1987.

  10. Feeding Ecology of Two Plecopterans in Low Order Andean-Patagonian Streams

    NASA Astrophysics Data System (ADS)

    Albariño, Ricardo J.; Díaz Villanueva, Verónica

    2006-05-01

    Feeding plasticity of the Andean plecopteran Klapopteryx kuscheli and Notoperla archiplatae larvae was assessed through a field experiment using enclosures. K. kuscheli has previously been described as a shredder and N. archiplatae as a scraper. Further information on gut contents from different populations supported those results. In the experiment, larvae of both species were exposed to contrasting food items: leaf litter and periphyton. Consumption, growth and the efficiency of food conversion were measured. K. kuscheli was able to feed on periphyton, though it did not grow. N. archiplatae failed to feed on leaf litter. While K. kuscheli might be considered a facultative shredder, N. archiplatae functions as a specialist scraper. The natural distribution and seasonal abundance in two small streams showed contrasting habitat use of both species. N. archiplatae inhabited high velocity runs and riffles underneath large substrates while K. kuscheli presented a higher habitat plasticity. Implications of those results for ecosystem function are discussed.

  11. Pathogenic regulation of running water macroinvertebrates

    SciTech Connect

    Cummins, K.W.; Wilzbach, M.A.

    1989-01-01

    The research during the second year focused on a large scale laboratory and field experiment on factors regulating growth and mortality of populations of the stream shredder caddisfly {ital Pycnopsyche guttifer}. This species, which is an obligate shredder feeding on leaf litter in woodland streams during its autumn-winter growth period, was selected because of the extensive pool of background data that are available, the ease with which its terrestrial eggs can be collected, and its suitability for laboratory culture and field observations. The species is univoltine and it is widely distributed in the eastern US, but did not occur naturally in the specific stream, Piney Run, MD, into which a population was introduced. 13 figs., 1 tab.

  12. Effects of an oil spill on leafpack-inhabiting macroinvertebrates in the Chariton river, Missouri

    USGS Publications Warehouse

    Poulton, B.C.; Callahan, E.V.; Hurtubise, R.D.; Mueller, B.G.

    1998-01-01

    Artificial leaf packs were used to determine the effects of an oil spill on stream macroinvertebrate communities in the Chariton River, Missouri. Plastic mesh leaf retainers with approximately 10 g of leaves from five tree species were deployed at five sites (two upstream of the spill and three downstream) immediately after the spill and one year later. Four macroinvertebrate species dominating the community at upstream sites were virtually eliminated below the spill, including the stonefly Isoperla bilineata, the caddisfly Potamyia flava, the midge Thienemanniella xena, and blackfly larvae (Simulium sp.). Density of collector and shredder functional groups, and number of shredder taxa differed between upstream sites and the two furthest downstream sites during the 1990 sample period (Kruskal-Wallis w/Bonferroni paired comparisons, experiment wise error rate = 0.05). With one exception, no differences between sites were detected in the 1991-1992 sample period, indicating that the benthic community had at least partially recovered from the oil spill after one year. The odds of obtaining a sample with a small abundance of shredders (abundance < median) in 1990 was significantly greater downstream of the spill than upstream, and the odds of obtaining a sample with a small abundance of shredders at downstream sites was greater in 1990 than in 1991-1992. A similar pattern was observed in abundance and taxa richness of the collector functional group. No significant differences between the two sampling periods were detected at upstream sites. Observed effects appeared to be associated with oil sorption and substrate coating, creating conditions unsuitable for successful colonization.

  13. Report: recycling of flame-retarded plastics from waste electric and electronic equipment (WEEE).

    PubMed

    Schlummer, Martin; Mäurer, Andreas; Leitner, Thomas; Spruzina, Walter

    2006-12-01

    Shredder residues produced in plants processing waste electric and electronic equipment are excluded from material recycling due to a variety of polymeric materials and the presence of brominated flame retardants (BFR), which might contain banned polybrominated diphenyl ethers or toxic polybrominated dioxins and furans (PBDD/F). Herein we present a technological approach to transfer a significant portion of the shredder residue into recycled polymers. The technological approach consists of a density-based enrichment of styrenics, which are subjected to a solvolysis process (CreaSolv process) in a second stage. This stage allows the elimination of non-target polymers and extraction of BFR and PBDD/F. Pilot processing of 11.5 and 50 kg shredder residues indicated a material yield of about 50% in the density stage and 70-80% in the CreaSolv process, and an effective removal of BFR additives. The recycled products were proved to comply with threshold values defined by the European directive on the restriction of hazardous substances (RoHS) and the German Chemikalienverbotsverordnung. Mechanical material properties exhibited high tensile and flexural modules as well as slight impact strength, which qualify the products for applications in new electronic equipment.

  14. The recycling dilemma for advanced materials use: Automobile materials substitution

    SciTech Connect

    Field, F.R. III; Clark, J.P. )

    1991-01-01

    This paper discusses the difficulties associated with imposing recycling imperatives upon advanced materials development by examining the case of automotive materials substitution and its impacts upon the recyclability of the automobile. Parallels are drawn between today's issues, which focus upon the recyclability of the increasing polymeric fraction in automobile shredder fluff, and the junked automobile problem of the 1960's, when the problem of abandoned automobiles became a part of the environmental and legislative agenda in the US and overseas. In the 1960's, both the source and the resolution of the junk automobile problem arose through a confluence of technological and economic factors, rather than through any set of regulatory influences. The rise of electric arc furnace steelmaking and the development of the automobile shredder were sufficient to virtually eliminate the problem - so much so that today's problems are incorrectly viewed as novelties. Today's automobile recycling problem again derives from technological and economic factors, but regulatory influences have spurred some of them. While there are no lack of technological solutions to the problem of automobile shredder fluff, none of these solutions yet provides scrap processors with the kind of profit opportunity necessary to implement them. In some ways, it is implicit in advanced materials markets that there is little to no demand for recycled forms of these materials, and, in the absence of these markets, there are few reasons to expect that the solution to today's problems will be quite so neat.

  15. The safety of non-incineration waste disposal devices in four hospitals of Tehran

    PubMed Central

    Farshad, Aliasghar; Gholami, Hamid; Farzadkia, Mahdi; Mirkazemi, Roksana; Kermani, Majid

    2014-01-01

    Background: The safe management of hospital waste is a challenge in many developing countries. Objectives: The aim of this study was to compare volatile organic compounds (VOCs) emissions and the microbial disinfectant safety in non-incineration waste disposal devices. Methods: VOC emissions and microbial infections were measured in four non-incineration waste disposal devices including: autoclave with and without a shredder, dry heat system, and hydroclave. Using NIOSH and US EPA-TO14 guidelines, the concentration and potential risk of VOCs in emitted gases from four devices were assessed. ProSpore2 biological indicators were used to assess the microbial analysis of waste residue. Results: There was a significant difference in the type and concentration of VOCs and microbial infection of residues in the four devices. Emissions from the autoclave with a shredder had the highest concentration of benzene, ethyl benzene, xylene, and BTEX, and emissions from the hydroclave had the highest concentration of toluene. The highest level of microbial infection was observed in the residues of the autoclave without a shredder. Conclusions: There is an increased need for proper regulation and control of non-incinerator devices and for monitoring and proper handling of these devices in developing countries. PMID:25000113

  16. Effects of flow scarcity on leaf-litter processing under oceanic climate conditions in calcareous streams.

    PubMed

    Martínez, Aingeru; Pérez, Javier; Molinero, Jon; Sagarduy, Mikel; Pozo, Jesús

    2015-01-15

    Although temporary streams represent a high proportion of the total number and length of running waters, historically the study of intermittent streams has received less attention than that of perennial ones. The goal of the present study was to assess the effects of flow cessation on litter decomposition in calcareous streams under oceanic climate conditions. For this, leaf litter of alder was incubated in four streams (S1, S2, S3 and S4) with different flow regimes (S3 and S4 with zero-flow periods) from northern Spain. To distinguish the relative importance and contribution of decomposers and detritivores, fine- and coarse-mesh litter bags were used. We determined processing rates, leaf-C, -N and -P concentrations, invertebrate colonization in coarse bags and benthic invertebrates. Decomposition rates in fine bags were similar among streams. In coarse bags, only one of the intermittent streams, S4, showed a lower rate than that in the other ones as a consequence of lower invertebrate colonization. The material incubated in fine bags presented higher leaf-N and -P concentrations than those in the coarse ones, except in S4, pointing out that the decomposition in this stream was driven mainly by microorganisms. Benthic macroinvertebrate and shredder density and biomass were lower in intermittent streams than those in perennial ones. However, the bags in S3 presented a greater amount of total macroinvertebrates and shredders comparing with the benthos. The most suitable explanation is that the fauna find a food substrate in bags less affected by calcite precipitation, which is common in the streambed at this site. Decomposition rate in coarse bags was positively related to associated shredder biomass. Thus, droughts in streams under oceanic climate conditions affect mainly the macroinvertebrate detritivore activity, although macroinvertebrates may show distinct behavior imposed by the physicochemical properties of water, mainly travertine precipitation, which can

  17. Trophic interactions determine the effects of drought on an aquatic ecosystem.

    PubMed

    Amundrud, Sarah L; Srivastava, Diane S

    2016-06-01

    Species interactions can be important mediators of community and ecosystem responses to environmental stressors. However, we still lack a mechanistic understanding of the indirect ecological effects of stress that arise via altered species interactions. To understand how species interactions will be altered by environmental stressors, we need to know if the species that are vulnerable to such stressors also have large impacts on the ecosystem. As predators often exhibit certain traits that are linked to a high vulnerability to stress (e.g., large body size, long generation time), as well as having large effects on communities (e.g., top-down trophic effects), predators may be particularly likely to mediate ecological effects of environmental stress. Other functional groups, like facilitators, are known to have large impacts on communities, but their vulnerability to perturbations remains undocumented. Here, we use aquatic insect communities in bromeliads to examine the indirect effects of an important stressor (drought) on community and ecosystem responses. In a microcosm experiment, we manipulated predatory and facilitative taxa under a range of experimental droughts, and quantified effects on community structure and ecosystem function. Drought, by adversely affecting the top predator, had indirect cascading effects on the entire food web, altering community composition and decomposition. We identified the likely pathway of how drought cascaded through the food web from the top-down as drought -->predator --> shredder --> decomposition. This stress-induced cascade depended on predators exhibiting both a strong vulnerability to drought and large impacts on prey (especially shredders), as well as shredders exhibiting high functional importance as decomposers. PMID:27459778

  18. Quantification of methane emissions from 15 Danish landfills using the mobile tracer dispersion method

    SciTech Connect

    Mønster, Jacob; Samuelsson, Jerker; Scheutz, Charlotte

    2015-01-15

    Highlights: • Quantification of whole landfill site methane emission at 15 landfills. • Multiple on-site source identification and quantification. • Quantified methane emission from shredder waste and composting. • Large difference between measured and reported methane emissions. - Abstract: Whole-site methane emissions from 15 Danish landfills were assessed using a mobile tracer dispersion method with either Fourier transform infrared spectroscopy (FTIR), using nitrous oxide as a tracer gas, or cavity ring-down spectrometry (CRDS), using acetylene as a tracer gas. The landfills were chosen to represent the different stages of the lifetime of a landfill, including open, active, and closed covered landfills, as well as those with and without gas extraction for utilisation or flaring. Measurements also included landfills with biocover for oxidizing any fugitive methane. Methane emission rates ranged from 2.6 to 60.8 kg h{sup −1}, corresponding to 0.7–13.2 g m{sup −2} d{sup −1}, with the largest emission rates per area coming from landfills with malfunctioning gas extraction systems installed, and the smallest emission rates from landfills closed decades ago and landfills with an engineered biocover installed. Landfills with gas collection and recovery systems had a recovery efficiency of 41–81%. Landfills where shredder waste was deposited showed significant methane emissions, with the largest emission from newly deposited shredder waste. The average methane emission from the landfills was 154 tons y{sup −1}. This average was obtained from a few measurement campaigns conducted at each of the 15 landfills and extrapolating to annual emissions requires more measurements. Assuming that these landfills are representative of the average Danish landfill, the total emission from Danish landfills were calculated at 20,600 tons y{sup −1}, which is significantly lower than the 33,300 tons y{sup −1} estimated for the national greenhouse gas inventory for

  19. Trophic interactions determine the effects of drought on an aquatic ecosystem.

    PubMed

    Amundrud, Sarah L; Srivastava, Diane S

    2016-06-01

    Species interactions can be important mediators of community and ecosystem responses to environmental stressors. However, we still lack a mechanistic understanding of the indirect ecological effects of stress that arise via altered species interactions. To understand how species interactions will be altered by environmental stressors, we need to know if the species that are vulnerable to such stressors also have large impacts on the ecosystem. As predators often exhibit certain traits that are linked to a high vulnerability to stress (e.g., large body size, long generation time), as well as having large effects on communities (e.g., top-down trophic effects), predators may be particularly likely to mediate ecological effects of environmental stress. Other functional groups, like facilitators, are known to have large impacts on communities, but their vulnerability to perturbations remains undocumented. Here, we use aquatic insect communities in bromeliads to examine the indirect effects of an important stressor (drought) on community and ecosystem responses. In a microcosm experiment, we manipulated predatory and facilitative taxa under a range of experimental droughts, and quantified effects on community structure and ecosystem function. Drought, by adversely affecting the top predator, had indirect cascading effects on the entire food web, altering community composition and decomposition. We identified the likely pathway of how drought cascaded through the food web from the top-down as drought -->predator --> shredder --> decomposition. This stress-induced cascade depended on predators exhibiting both a strong vulnerability to drought and large impacts on prey (especially shredders), as well as shredders exhibiting high functional importance as decomposers.

  20. Shifts in leaf litter breakdown along a forest-pasture-urban gradient in Andean streams.

    PubMed

    Iñiguez-Armijos, Carlos; Rausche, Sirkka; Cueva, Augusta; Sánchez-Rodríguez, Aminael; Espinosa, Carlos; Breuer, Lutz

    2016-07-01

    Tropical montane ecosystems of the Andes are critically threatened by a rapid land-use change which can potentially affect stream variables, aquatic communities, and ecosystem processes such as leaf litter breakdown. However, these effects have not been sufficiently investigated in the Andean region and at high altitude locations in general. Here, we studied the influence of land use (forest-pasture-urban) on stream physico-chemical variables (e.g., water temperature, nutrient concentration, and pH), aquatic communities (macroinvertebrates and aquatic fungi) and leaf litter breakdown rates in Andean streams (southern Ecuador), and how variation in those stream physico-chemical variables affect macroinvertebrates and fungi related to leaf litter breakdown. We found that pH, water temperature, and nutrient concentration increased along the land-use gradient. Macroinvertebrate communities were significantly different between land uses. Shredder richness and abundance were lower in pasture than forest sites and totally absent in urban sites, and fungal richness and biomass were higher in forest sites than in pasture and urban sites. Leaf litter breakdown rates became slower as riparian land use changed from natural to anthropogenically disturbed conditions and were largely determined by pH, water temperature, phosphate concentration, fungal activity, and single species of leaf-shredding invertebrates. Our findings provide evidence that leaf litter breakdown in Andean streams is sensitive to riparian land-use change, with urban streams being the most affected. In addition, this study highlights the role of fungal biomass and shredder species (Phylloicus; Trichoptera and Anchytarsus; Coleoptera) on leaf litter breakdown in Andean streams and the contribution of aquatic fungi in supporting this ecosystem process when shredders are absent or present low abundance in streams affected by urbanization. Finally, we summarize important implications in terms of managing of

  1. Shifts in leaf litter breakdown along a forest-pasture-urban gradient in Andean streams.

    PubMed

    Iñiguez-Armijos, Carlos; Rausche, Sirkka; Cueva, Augusta; Sánchez-Rodríguez, Aminael; Espinosa, Carlos; Breuer, Lutz

    2016-07-01

    Tropical montane ecosystems of the Andes are critically threatened by a rapid land-use change which can potentially affect stream variables, aquatic communities, and ecosystem processes such as leaf litter breakdown. However, these effects have not been sufficiently investigated in the Andean region and at high altitude locations in general. Here, we studied the influence of land use (forest-pasture-urban) on stream physico-chemical variables (e.g., water temperature, nutrient concentration, and pH), aquatic communities (macroinvertebrates and aquatic fungi) and leaf litter breakdown rates in Andean streams (southern Ecuador), and how variation in those stream physico-chemical variables affect macroinvertebrates and fungi related to leaf litter breakdown. We found that pH, water temperature, and nutrient concentration increased along the land-use gradient. Macroinvertebrate communities were significantly different between land uses. Shredder richness and abundance were lower in pasture than forest sites and totally absent in urban sites, and fungal richness and biomass were higher in forest sites than in pasture and urban sites. Leaf litter breakdown rates became slower as riparian land use changed from natural to anthropogenically disturbed conditions and were largely determined by pH, water temperature, phosphate concentration, fungal activity, and single species of leaf-shredding invertebrates. Our findings provide evidence that leaf litter breakdown in Andean streams is sensitive to riparian land-use change, with urban streams being the most affected. In addition, this study highlights the role of fungal biomass and shredder species (Phylloicus; Trichoptera and Anchytarsus; Coleoptera) on leaf litter breakdown in Andean streams and the contribution of aquatic fungi in supporting this ecosystem process when shredders are absent or present low abundance in streams affected by urbanization. Finally, we summarize important implications in terms of managing of

  2. Separation of non-ferrous metals from ASR by corona electrostatic separation

    NASA Astrophysics Data System (ADS)

    Kim, Yang-soo; Choi, Jin-Young; Jeon, Ho-Seok; Han, Oh-Hyung; Park, Chul-Hyun

    2016-04-01

    Automotive shredder residue (ASR), the residual fraction of approximate 25% obtained after dismantling and shredding from waste car, consists of polymers (plastics and rubber), metals (ferrous and non-ferrous), wood, glass and fluff (textile and fiber). ASR cannot be effectively separated due to its heterogeneous materials and coated or laminated complexes and then largely deposited in land-fill sites as waste. Thus reducing a pollutant release before disposal, techniques that can improve the liberation of coated (or laminated) complexes and the recovery of valuable metals from the shredder residue are needed. ASR may be separated by a series of physical processing operations such as comminution, air, magnetic and electrostatic separations. The work deals with the characterization of the shredder residue coming from an industrial plant in korea and focuses on estimating the optimal conditions of corona electrostatic separation for improving the separation efficiency of valuable non-ferrous metals such as aluminum, copper and etc. From the results of test, the maximum separation achievable for non-ferrous metals using a corona electrostatic separation has been shown to be recovery of 92.5% at a grade of 75.8%. The recommended values of the process variables, particle size, electrode potential, drum speed, splitter position and relative humidity are -6mm, 50 kV, 35rpm, 20° and less 40%, respectively. Acknowledgments This study was supported by the R&D Center for Valuable Recycling (Global-Top R&BD Program) of the Ministry of Environment. (Project No. GT-11-C-01-170-0)

  3. Effects of flow scarcity on leaf-litter processing under oceanic climate conditions in calcareous streams.

    PubMed

    Martínez, Aingeru; Pérez, Javier; Molinero, Jon; Sagarduy, Mikel; Pozo, Jesús

    2015-01-15

    Although temporary streams represent a high proportion of the total number and length of running waters, historically the study of intermittent streams has received less attention than that of perennial ones. The goal of the present study was to assess the effects of flow cessation on litter decomposition in calcareous streams under oceanic climate conditions. For this, leaf litter of alder was incubated in four streams (S1, S2, S3 and S4) with different flow regimes (S3 and S4 with zero-flow periods) from northern Spain. To distinguish the relative importance and contribution of decomposers and detritivores, fine- and coarse-mesh litter bags were used. We determined processing rates, leaf-C, -N and -P concentrations, invertebrate colonization in coarse bags and benthic invertebrates. Decomposition rates in fine bags were similar among streams. In coarse bags, only one of the intermittent streams, S4, showed a lower rate than that in the other ones as a consequence of lower invertebrate colonization. The material incubated in fine bags presented higher leaf-N and -P concentrations than those in the coarse ones, except in S4, pointing out that the decomposition in this stream was driven mainly by microorganisms. Benthic macroinvertebrate and shredder density and biomass were lower in intermittent streams than those in perennial ones. However, the bags in S3 presented a greater amount of total macroinvertebrates and shredders comparing with the benthos. The most suitable explanation is that the fauna find a food substrate in bags less affected by calcite precipitation, which is common in the streambed at this site. Decomposition rate in coarse bags was positively related to associated shredder biomass. Thus, droughts in streams under oceanic climate conditions affect mainly the macroinvertebrate detritivore activity, although macroinvertebrates may show distinct behavior imposed by the physicochemical properties of water, mainly travertine precipitation, which can

  4. Advanced process research and development to enhance metals and materials recycling.

    SciTech Connect

    Daniels, E. J.

    1997-12-05

    Innovative, cost-effective technologies that have a positive life-cycle environmental impact and yield marketable products are needed to meet the challenges of the recycling industry. Four materials-recovery technologies that are being developed at Argonne National Laboratory in cooperation with industrial partners are described in this paper: (1) dezincing of galvanized steel scrap; (2) material recovery from auto-shredder residue; (3) high-value-plastics recovery from obsolete appliances; and (4) aluminum salt cake recycling. These technologies are expected to be applicable to the production of low-cost, high-quality raw materials from a wide range of waste streams.

  5. Energy from waste via coal/waste co-firing

    SciTech Connect

    Winslow, J.; Ekmann, J.; Smouse, S.; Ramezan, M.; Harding, S.

    1996-12-31

    The paper reviews the feasibility of waste-to-energy plants using the cocombustion of coal with refuse-derived fuels. The paper discusses the types of wastes available: municipal solid wastes, plastics, tires, biomass, and specialized industrial wastes, such as waste oils, post-consumer carpet, auto shredder residues, and petroleum coke. The five most common combustion systems used in co-firing are briefly described. They are the stoker boiler, suspension-fired boilers, cyclone furnaces, fluidized bed boilers, and cement kilns. The paper also discusses the economic incentives for generating electricity from waste.

  6. Mechanism for coordination between the collector and the dismantler in a reverse supply chain

    NASA Astrophysics Data System (ADS)

    Pochampally, Kishore K.; Gupta, Surendra M.

    2005-11-01

    The growing desire of consumers to acquire the latest technology (both at home and in the workplace), along with the rapid technological development of new products, has led to a new environmental problem: waste. The only way to tackle this problem is design and implementation of reverse supply chains. Implementation of an efficient reverse supply chain requires coordination among a number of parties, such as the collector, the dismantler, the shredder, and the recycler. In this paper, we identify four different scenarios of homogeneous and heterogeneous products, and formulate some potential interactions between the collector and the dismantler, for each of those scenarios.

  7. AFBC co-firing of coal and hospital waste. Quarterly progress report, November 1, 1994--January 31, 1995

    SciTech Connect

    Stuart, J.M.

    1995-10-01

    The project objective is to design, construct, install, and start-up a circulating fluidized bed combustion system at the Lebanon, Pennsylvania Veteran`s Affairs Medical Center. The unit will co-fire coal and hospital waste providing inexpensive and efficient destruction of both general and infectious medical waste and steam generation. Progress to date on several tasks is described. These are: Task 1.A-1.D, Design; Equipment purchase and fabrication; Installation; and Shredder system verification. Other tasks to be undertaken are: Start-up; Obtaining permits; Procuring coal, limestone and ash disposal contracts; and Conducting on-year test program. Project costs are enumerated.

  8. Sink-float ferrofluid separator applicable to full scale nonferrous scrap separation

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Design and performance of a ferrofluid levitation separator for recovering nonferrous metals from shredded automobiles are reported. The scrap separator uses an electromagnet to generate a region of constant density within a pool of ferrofluid held between the magnetic poles; a saturated kerosene base ferrofluid as able to float all common industrial metals of interest. Conveyors move the scrap into the ferrofluid for separation according to density. Results of scrap mixture separation studies establish the technical feasibility of relatively pure aluminum alloy and zinc alloy fractions from shredded automobile scrap by this ferrofluid levitation process. Economic projections indicate profitable operation for shredders handling more than 300 cars per day.

  9. Release of fluorocarbons from insulation foam in home appliances during shredding.

    PubMed

    Scheutz, Charlotte; Fredenslund, Anders M; Kjeldsen, Peter; Tant, Michael

    2007-12-01

    It is a current practice that refrigerators and freezers in many countries are shredded after the end of useful lives. The shredder residue is deposited in landfills. During the shredding process a significant fraction of blowing agent (BA) in the insulation foam may be released into the atmosphere. The objective of this study is to determine the fraction of BA released from foam during shredding, by comparing the BA content in insulation foam of refrigerator units before shredding with the BA content of shredded foam. All foam samples analyzed were manufactured with trichlorofluoromethane [CFC-11 (CCl3F)] as BA. The average content of BA in the insulation foam from eight U.S. refrigerator units manufactured before 1993 was found to be 14.9% +/- 3.3% w/w. Several refrigerator units also identified as being manufactured before 1993 were stockpiled and shredded at three shredder facilities, of which one was operated in both wet and dry modes. The selected shredder facilities represent typical American facilities for shredding automobiles, refrigerators, freezers, and other iron containing waste products. Shredded material was collected and separated on location into four particle size categories: more than 32 mm, 16-32 mm, 8-16 mm, and 0-8 mm. Adjusting for sample purity, it was found that the majority (>81%) of the foam mass was shredded into particles larger than 16 mm. The smallest size fraction of foam (0-8 mm) was found to contain significantly less BA than the larger size categories, showing that up to 68% +/- 4% of the BA is released from these fine particles during the shredding process. Because only a minor fraction of the foam is shredded into particles smaller than 8 mm, this has a minor impact on the end result when calculating the total BA release from the shredding process. Comparing BA content in shredded samples from the three shredder facilities with the measured average BA content of the eight refrigerator units, it was found that on average 24

  10. Knowledge and practice of confidential data handling in the Welsh Deanery: a brief report.

    PubMed

    Jackson, L E; Lim, M W

    2011-01-01

    Recent large-scale personal data loss incidents highlighted the need for public bodies to more securely handle confidential data. We surveyed trainees from all specialties in the Welsh Deanery for their knowledge and practice. All registered trainees were invited to participate in an online anonymised survey. There were 880 completed and non-duplicated responses (52.9% response rate). Responses were analysed using Microsoft Access. Over 40% (388/880 (44.1%)) did not use formal guidelines on storage or disposal of confidential data. The majority appeared to dispose of confidential paper documents securely, that is, using shredders and white shredder bags. However, there were significant numbers of unmarked responses. Clinical documents, such as theatre lists, were taken home by 281/880 (31.9%) of trainees. The majority secured their computers (569/871 (65.3%)) by either not keeping patient identifiable data on them or using encryption. However, 302/871 (34.7%) did not adequately secure their computers. The surgical and anaesthetic specialties were least aware of formal confidentiality guidelines (95/178 (53.4%)) and 52/102 (51.0%) respectively) and least secured their computers (106/178 (59.6%) and 63/102 (61.8%) respectively). Education is needed to improve knowledge and practice of confidential data handling. This may be delivered through workshops during induction programmes or as part of European Computer Driving Licence (ECDL) modules. Training is especially indicated for the surgical and anaesthetic specialties.

  11. Using sieving and pretreatment to separate plastics during end-of-life vehicle recycling.

    PubMed

    Stagner, Jacqueline A; Sagan, Barsha; Tam, Edwin Kl

    2013-09-01

    Plastics continue to be a challenge for recovering materials at the end-of-life for vehicles. However, it may be possible to improve the recovery of plastics by exploiting material characteristics, such as shape, or by altering their behavior, such as through temperature changes, in relation to recovery processes and handling. Samples of a 2009 Dodge Challenger front fascia were shredded in a laboratory-scale hammer mill shredder. A 2 × 2 factorial design study was performed to determine the effect of sample shape (flat versus curved) and sample temperature (room temperature versus cryogenic temperature) on the size of the particles exiting from the shredder. It was determined that sample shape does not affect the particle size; however, sample temperature does affect the particle size. At cryogenic temperatures, the distribution of particle sizes is much narrower than at room temperature. Having a more uniform particle size could make recovery of plastic particles, such as these more efficient during the recycling of end-of-life vehicles. Samples of Chrysler minivan headlights were also shredded at room temperature and at cryogenic temperatures. The size of the particles of the two different plastics in the headlights is statistically different both at room temperature and at cryogenic temperature, and the particles are distributed narrowly. The research suggests that incremental changes in end-of-life vehicle processing could be effective in aiding materials recovery.

  12. Thermal-nutritional regulation of functional groups in running water ecosystems. Technical progress report, October 1, 1978-November 1, 1980

    SciTech Connect

    Cummins, K.W.

    1980-11-01

    The research encompassed three general areas: (1) characterization of stream macroinvertebrate functional feeding groups (shredders, collectors, scrapers, and predators) based on morphological and behavioral adaptations and food-source-specific growth responses of selected species; (2) demonstration of the relative importance of temperature and food quality (in which maximum quality is defined as that producing the most growth) in controlling growth rate and survivorship of stream functional groups; and (3) derivation and refinement of conceptual and quantitative models of stream ecosystem structure and function, with particular emphasis on detrital processing. Verification of the functional group concept as a tool for assessing and predicting is reflected in alterations of the relative dominance of various functional groups. Food quality can strongly influence the growth rates of shredders, collectors and scrapers and override the effects of temperature in a number of cases. Gathering collectors may select food particles by size (or at least be restricted to a limited portion of the total range available) but representative species do not appear to select for quality.

  13. Genetically modified crops and aquatic ecosystems: considerations for environmental risk assessment and non-target organism testing.

    PubMed

    Carstens, Keri; Anderson, Jennifer; Bachman, Pamela; De Schrijver, Adinda; Dively, Galen; Federici, Brian; Hamer, Mick; Gielkens, Marco; Jensen, Peter; Lamp, William; Rauschen, Stefan; Ridley, Geoff; Romeis, Jörg; Waggoner, Annabel

    2012-08-01

    Environmental risk assessments (ERA) support regulatory decisions for the commercial cultivation of genetically modified (GM) crops. The ERA for terrestrial agroecosystems is well-developed, whereas guidance for ERA of GM crops in aquatic ecosystems is not as well-defined. The purpose of this document is to demonstrate how comprehensive problem formulation can be used to develop a conceptual model and to identify potential exposure pathways, using Bacillus thuringiensis (Bt) maize as a case study. Within problem formulation, the insecticidal trait, the crop, the receiving environment, and protection goals were characterized, and a conceptual model was developed to identify routes through which aquatic organisms may be exposed to insecticidal proteins in maize tissue. Following a tiered approach for exposure assessment, worst-case exposures were estimated using standardized models, and factors mitigating exposure were described. Based on exposure estimates, shredders were identified as the functional group most likely to be exposed to insecticidal proteins. However, even using worst-case assumptions, the exposure of shredders to Bt maize was low and studies supporting the current risk assessments were deemed adequate. Determining if early tier toxicity studies are necessary to inform the risk assessment for a specific GM crop should be done on a case by case basis, and should be guided by thorough problem formulation and exposure assessment. The processes used to develop the Bt maize case study are intended to serve as a model for performing risk assessments on future traits and crops.

  14. Recent trends in automobile recycling: An energy and economic assessment

    SciTech Connect

    Curlee, T.R.; Das, S.; Rizy, C.G.; Schexanyder, S.M.

    1994-03-01

    Recent and anticipated trends in the material composition of domestic and imported automobiles and the increasing cost of landfilling the non-recyclable portion of automobiles (automobile shredder residue or ASR) pose questions about the future of automobile recycling. This report documents the findings of a study sponsored by the US Department of Energy`s Office of Environmental Analysis to examine the impacts of these and other relevant trends on the life-cycle energy consumption of automobiles and on the economic viability of the domestic automobile recycling industry. More specifically, the study (1) reviewed the status of the automobile recycling industry in the United States, including the current technologies used to process scrapped automobiles and the challenges facing the automobile recycling industry; (2) examined the current status and future trends of automobile recycling in Europe and Japan, with the objectives of identifying ``lessons learned`` and pinpointing differences between those areas and the United States; (3) developed estimates of the energy system impacts of the recycling status quo and projections of the probable energy impacts of alternative technical and institutional approaches to recycling; and (4) identified the key policy questions that will determine the future economic viability of automobile shredder facilities in the United States.

  15. Comparison of Degradative Ability, Enzymatic Activity, and Palatability of Aquatic Hyphomycetes Grown on Leaf Litter

    PubMed Central

    Suberkropp, Keller; Arsuffi, Thomas L.; Anderson, John P.

    1983-01-01

    Stream fungi have the capacity to degrade leaf litter and, through their activities, to transform it into a more palatable food source for invertebrate detritivores. The objectives of the present study were to characterize various aspects of fungal modification of the leaf substrate and to examine the effects these changes have on leaf palatability to detritivores. Fungal species were grown on aspen leaves for two incubation times. Leaves were analyzed to determine the weight loss, the degree of softening of the leaf matrix, and the concentrations of ATP and nitrogen associated with leaves. The activities of a protease and 10 polysaccharide-degrading enzymes produced by each fungus were also determined. Most fungi caused similar changes in physicochemical characteristics of the leaves. All fungi exhibited the capability to depolymerize pectin, xylan, and cellulose. Differences among fungi were found in their capabilities to produce protease and certain glycosidases. Leaf palatability was assessed by offering leaves of all treatments to larvae of two caddisfly shredders (Trichoptera). Feeding preferences exhibited by the shredders were similar and indicated that they perceived distinct differences among fungi. Two fungal species were highly consumed, some moderately and others only slightly. No relationships were found between any of the fungal characteristics measured and detritivore feeding preferences. Apparently, interspecific differences among fungi other than parameters associated with biomass or degradation of structural polysaccharides influence fungal palatability to caddisfly detritivores. PMID:16346343

  16. The leaf breakdown of Picramnia sellowii (Picramniales: Picramniaceae) as index of anthropic disturbances in tropical streams.

    PubMed

    Lopes, M P; Martins, R T; Silveira, L S; Alves, R G

    2015-11-01

    There are few studies in tropical regions exploring the use of leaf breakdown process as a functional tool to assess anthropic disturbance on aquatic ecosystems. We assessed the effects of water pollution due to human activities on the leaf breakdown rate of Picramnia sellowii in streams of the southeastern Brazil. The experiment was carried out for 60 days in three reference streams and three streams impaired by organic pollution and absence of riparian vegetation. Three litter bags were incubated in each stream containing 3 ± 0.05 g of P. sellowii leaves. The reference streams presented higher values of dissolved oxygen and lower values of nutrients, turbidity, electrical conductivity, total impermeable area and water temperature. The leaf breakdown rate (k) differed significantly between the reference (k = 0.014 ± 0.003 d-1) and impaired streams (k = 0.005 ± 0.001 d-1). The leaves incubated in the reference streams contained greater fungal biomass (measured as ergosterol concentration) and abundance of invertebrates, as well as greater presence of shredders, with k values being related to the biomass of these organisms. Overall, there were clear differences between the leaf mass loss in the reference and impaired streams. These results reinforce the negative effect of urbanization on leaf breakdown and fungal and shredder biomass. PMID:26628230

  17. Effects of anthropogenic salinization on biological traits and community composition of stream macroinvertebrates.

    PubMed

    Szöcs, Eduard; Coring, Eckhard; Bäthe, Jürgen; Schäfer, Ralf B

    2014-01-15

    Salinization of rivers resulting from industrial discharge or road-deicing can adversely affect macroinvertebrates. Trait-based approaches are a promising tool in ecological monitoring and may perform better than taxonomy-based approaches. However only little is known how and which biological traits are affected by salinization. We investigated the effects of anthropogenic salinization on macroinvertebrate communities and biological traits in the Werra River, Germany and compared the taxonomic and trait response. We found a change in macroinvertebrate community and trait composition. Communities at saline sites were characterized by the three exotic species Gammarus tigrinus, Apocorophium lacustre and Potamopyrgus antipodarum. The frequencies of trait modalities long life cycle duration, respiration by gill, ovoviviparity, shredder and multivoltinism were statistically significantly increased at saline sites. The trait-based ordination resulted in a higher explained variance than the taxonomy-based ordination, indicating a better performance of the trait-based approach, resulting in a better discrimination between saline and non-saline sites. Our results are in general agreement with other studies from Europe, indicating a trait convergence for saline streams, being dominated by the traits ovoviviparity and multivoltinism. Three further traits (respiration by gill, life cycle duration and shredders) responded strongly to salinization, but this may primarily be attributed to the dominance of a single invasive species, G. tigrinus, at the saline sites in the Werra River.

  18. Effects of hydrologic connectivity on aquatic macroinvertebrate assemblages in different marsh types

    USGS Publications Warehouse

    Kang, Sung-Ryong; King, Sammy L.

    2013-01-01

    Hydrologic connectivity can be an important driver of aquatic macroinvertebrate assemblages. Its effects on aquatic macroinvertebrate assemblages in coastal marshes, however, are relatively poorly studied. We evaluated the effects of lateral hydrologic connectivity (permanently connected ponds: PCPs; temporary connected ponds: TCPs), and other environmental variables on aquatic macroinvertebrate assemblages and functional feeding groups (FFGs) in freshwater, brackish, and saline marshes in Louisiana, USA. We hypothesized that (1) aquatic macroinvertebrate assemblages in PCPs would have higher assemblage metric values (density, biomass, Shannon-Wiener diversity) than TCPs and (2) the density and proportional abundance of certain FFGs (i.e. scrapers, shredders, and collectors) would be greater in freshwater marsh than brackish and saline marshes. The data in our study only partially supported our first hypothesis: while freshwater marsh PCPs had higher density and biomass than TCPs, assemblage metric values in saline TCPs were greater than saline PCPs. In freshwater TCPs, long duration of isolation limited access of macroinvertebrates from adjacent water bodies, which may have reduced assemblage metric values. However, the relatively short duration of isolation in saline TCPs provided more stable or similar habitat conditions, facilitating higher assemblage metric values. As predicted by our second hypothesis, freshwater PCPs and TCPs supported a greater density of scrapers, shredders, and collectors than brackish and saline ponds. Aquatic macroinvertebrate assemblages seem to be structured by individual taxa responses to salinity as well as pond habitat attributes.

  19. The leaf breakdown of Picramnia sellowii (Picramniales: Picramniaceae) as index of anthropic disturbances in tropical streams.

    PubMed

    Lopes, M P; Martins, R T; Silveira, L S; Alves, R G

    2015-11-01

    There are few studies in tropical regions exploring the use of leaf breakdown process as a functional tool to assess anthropic disturbance on aquatic ecosystems. We assessed the effects of water pollution due to human activities on the leaf breakdown rate of Picramnia sellowii in streams of the southeastern Brazil. The experiment was carried out for 60 days in three reference streams and three streams impaired by organic pollution and absence of riparian vegetation. Three litter bags were incubated in each stream containing 3 ± 0.05 g of P. sellowii leaves. The reference streams presented higher values of dissolved oxygen and lower values of nutrients, turbidity, electrical conductivity, total impermeable area and water temperature. The leaf breakdown rate (k) differed significantly between the reference (k = 0.014 ± 0.003 d-1) and impaired streams (k = 0.005 ± 0.001 d-1). The leaves incubated in the reference streams contained greater fungal biomass (measured as ergosterol concentration) and abundance of invertebrates, as well as greater presence of shredders, with k values being related to the biomass of these organisms. Overall, there were clear differences between the leaf mass loss in the reference and impaired streams. These results reinforce the negative effect of urbanization on leaf breakdown and fungal and shredder biomass.

  20. Gas production, composition and emission at a modern disposal site receiving waste with a low-organic content

    SciTech Connect

    Scheutz, Charlotte; Fredenslund, Anders M.; Nedenskov, Jonas; Samuelsson, Jerker

    2011-05-15

    AV Miljo is a modern waste disposal site receiving non-combustible waste with a low-organic content. The objective of the current project was to determine the gas generation, composition, emission, and oxidation in top covers on selected waste cells as well as the total methane (CH{sub 4}) emission from the disposal site. The investigations focused particularly on three waste disposal cells containing shredder waste (cell 1.5.1), mixed industrial waste (cell 2.2.2), and mixed combustible waste (cell 1.3). Laboratory waste incubation experiments as well as gas modeling showed that significant gas generation was occurring in all three cells. Field analysis showed that the gas generated in the cell with mixed combustible waste consisted of mainly CH{sub 4} (70%) and carbon dioxide (CO{sub 2}) (29%) whereas the gas generated within the shredder waste, primarily consisted of CH{sub 4} (27%) and nitrogen (N{sub 2}) (71%), containing no CO{sub 2}. The results indicated that the gas composition in the shredder waste was governed by chemical reactions as well as microbial reactions. CH{sub 4} mass balances from three individual waste cells showed that a significant part (between 15% and 67%) of the CH{sub 4} generated in cell 1.3 and 2.2.2 was emitted through leachate collection wells, as a result of the relatively impermeable covers in place at these two cells preventing vertical migration of the gas. At cell 1.5.1, which is un-covered, the CH{sub 4} emission through the leachate system was low due to the high gas permeability of the shredder waste. Instead the gas was emitted through the waste resulting in some hotspot observations on the shredder surface with higher emission rates. The remaining gas that was not emitted through surfaces or the leachate collection system could potentially be oxidized as the measured oxidation capacity exceeded the potential emission rate. The whole CH{sub 4} emission from the disposal site was found to be 820 {+-} 202 kg CH{sub 4} d

  1. Detrital stoichiometry as a critical nexus for the effects of streamwater nutrients on leaf litter breakdown rates.

    PubMed

    Manning, David W P; Rosemond, Amy D; Kominoski, John S; Gulis, Vladislav; Benstead, Jonathan P; Maerz, John C

    2015-08-01

    Nitrogen (N) and phosphorus (P) concentrations are elevated in many freshwater systems, stimulating breakdown rates of terrestrially derived plant litter; however, the relative importance of N and P in driving litter breakdown via microbial and detritivore processing are not fully understood. Here, we determined breakdown rates of two litter species, Acer rubrum (maple) and Rhododendron maximum (rhododendron), before (PRE) and during two years (YR1, YR2) of experimental N and P additions to five streams, and quantified the relative importance of hypothesized factors contributing to breakdown. Treatment streams received a gradient of P additions (low to high soluble reactive phosphorus [SRP]; ~10-85 µg/L) crossed with a gradient of N additions (high to low dissolved inorganic nitrogen [DIN]; ~472-96 µg/L) to achieve target molar N:P ratios ranging from 128 to 2. Litter breakdown rates increased above pre-treatment levels by an average of 1.1-2.2x for maple, and 2.7-4.9x for rhododendron in YR1 and YR2. We used path analysis to compare fungal biomass, shredder biomass, litter stoichiometry (nutrient content as C:N or C:P), discharge, and streamwater temperature as predictors of breakdown rates and compared models containing streamwater N, P or N + P and litter C:N or C:P using model selection criteria. Litter breakdown rates were predicted equally with either streamwater N or P (R2 = 0.57). In models with N or P, fungal biomass, litter stoichiometry, discharge, and shredder biomass predicted breakdown rates; litter stoichiometry and fungal biomass were most important for model fit. However, N and P effects may have occurred via subtly different pathways. Litter N content increased with fungal biomass (N-driven effects) and litter P content increased with streamwater P availability (P-driven effects), presumably via P storage in fungal biomass. In either case, the effects of N and P through these pathways were associated with higher shredder biomass and breakdown

  2. Longitudinal Distribution of the Functional Feeding Groups of Aquatic Insects in Streams of the Brazilian Cerrado Savanna.

    PubMed

    Brasil, L S; Juen, L; Batista, J D; Pavan, M G; Cabette, H S R

    2014-10-01

    We demonstrate that the distribution of the functional feeding groups of aquatic insects is related to hierarchical patch dynamics. Patches are sites with unique environmental and functional characteristics that are discontinuously distributed in time and space within a lotic system. This distribution predicts that the occurrence of species will be based predominantly on their environmental requirements. We sampled three streams within the same drainage basin in the Brazilian Cerrado savanna, focusing on waterfalls and associated habitats (upstream, downstream), representing different functional zones. We collected 2,636 specimens representing six functional feeding groups (FFGs): brushers, collector-gatherers, collector-filterers, shredders, predators, and scrapers. The frequency of occurrence of these groups varied significantly among environments. This variation appeared to be related to the distinct characteristics of the different habitat patches, which led us to infer that the hierarchical patch dynamics model can best explain the distribution of functional feeding groups in minor lotic environments, such as waterfalls. PMID:27193952

  3. Solid-phase fermentation and juice expression systems for sweet sorghum

    SciTech Connect

    Bryan, W.L.; Monroe, G.E.; Caussariel, P.M.

    1985-01-01

    Two systems to recover fermented juice from variety M 81E sweet sorghum stalks that contained about 11% fermentable sugar were compared. (a) Stalks with leaves and tops removed were chopped and inoculated with 0.2% yeast in a forage harvester, stored under anaerobic conditions for 75 hours in insulated fermentors and pressed in a screw press to recover fermented juice (5-6% ethanol). (b) Mechanically harvested sweet sorghum billets (30 cm length) without leaves or seed heads were shredded and milled in a 3-roll mill; and bagasse was inoculated with 0.2% yeast, fermented for 100 h and pressed to recover fermented juice (4 to 5% ethanol). Potential ethanol yields were 75% of theoretical for the forage harvest system and 78% for the shredder mill system, based on 95% of theoretical ethanol yield from juice expressed during milling and no loss of ethanol during fermentation, handling and pressing in the screw press. 20 references.

  4. Waste Management Facilities Cost Information Report

    SciTech Connect

    Feizollahi, F.; Shropshire, D.

    1992-10-01

    The Waste Management Facility Cost Information (WMFCI) Report, commissioned by the US Department of Energy (DOE), develops planning life-cycle cost (PLCC) estimates for treatment, storage, and disposal facilities. This report contains PLCC estimates versus capacity for 26 different facility cost modules. A procedure to guide DOE and its contractor personnel in the use of estimating data is also provided. Estimates in the report apply to five distinctive waste streams: low-level waste, low-level mixed waste, alpha contaminated low-level waste, alpha contaminated low-level mixed waste, and transuranic waste. The report addresses five different treatment types: incineration, metal/melting and recovery, shredder/compaction, solidification, and vitrification. Data in this report allows the user to develop PLCC estimates for various waste management options.

  5. Longitudinal Distribution of the Functional Feeding Groups of Aquatic Insects in Streams of the Brazilian Cerrado Savanna.

    PubMed

    Brasil, L S; Juen, L; Batista, J D; Pavan, M G; Cabette, H S R

    2014-10-01

    We demonstrate that the distribution of the functional feeding groups of aquatic insects is related to hierarchical patch dynamics. Patches are sites with unique environmental and functional characteristics that are discontinuously distributed in time and space within a lotic system. This distribution predicts that the occurrence of species will be based predominantly on their environmental requirements. We sampled three streams within the same drainage basin in the Brazilian Cerrado savanna, focusing on waterfalls and associated habitats (upstream, downstream), representing different functional zones. We collected 2,636 specimens representing six functional feeding groups (FFGs): brushers, collector-gatherers, collector-filterers, shredders, predators, and scrapers. The frequency of occurrence of these groups varied significantly among environments. This variation appeared to be related to the distinct characteristics of the different habitat patches, which led us to infer that the hierarchical patch dynamics model can best explain the distribution of functional feeding groups in minor lotic environments, such as waterfalls.

  6. MLSE and associates report: Engineering and economic analysis of processing used wood pallets, etc. to fuel

    SciTech Connect

    Smith, M.L.; Smith, M.L.; Boley, G.L.

    1993-05-01

    The pallet, real and container manufacturing industry produces nearly 500 million new units per year and uses over 9 million tons of wood, dry basis. About half of these units are returnable and are reused but eventually all the units must be disposed. With the increasing costs of landfilling and legislation to prohibit wood in landfills there is a need to utilize the wood in these units. Processing units to wood fuel is an option that can be used at many sites. Current methods to reduce pallets to small particles typically uses a primary and a secondary processor. Primary processors typically are tub mills, hammermills, shredders and crushers. Secondary processors are typically hammermills. Magnetic rolls are used to remove magnetic metals from the processed wood. Final size preparation is usually done to remove any over and under sized particles.

  7. Embryonic transcriptome of the brackishwater amphipod Gammarus chevreuxi.

    PubMed

    Truebano, Manuela; Tills, Oliver; Spicer, John I

    2016-08-01

    Environmental change can dramatically alter the development of aquatic organisms. While the effect of such change on physiological and morphological ontogenies is becoming clearer, the molecular mechanisms underpinning them are largely unexplored. Characterizing these mechanisms is often limited by the lack of molecular resources. We have applied Illumina HiSeq sequencing to RNA isolated from different developmental stages of the brackishwater amphipod Gammarus chevreuxi. Over 52.6M paired-end reads were assembled de novo into 172,081 contigs, representing 118,812 potential genes. The assembly generated constitutes a reference embryonic transcriptome for an ecologically-important aquatic shredder species. This resource will contribute to our understanding of the mechanisms underpinning the development of physiological function through functional, comparative and quantitative expression studies. It will also allow the identification of candidate biomarkers for assessing the impact of environmental stressors in estuarine systems.

  8. Trash will fuel new Columbus plant

    SciTech Connect

    Not Available

    1981-05-01

    Columbus, Ohio is building a refuse- and coal-fired 90-MW municipal electric plant that will burn 3000 tons of refuse a day. The plant will burn 80% trash and 20% low-sulfur coal (with the option of burning either all coal or all trash) because the 80-20 ratio offers the best balance between boiler corrosion and efficiency. A general obligation bond sale rather than federal or state financing is possible because of the city's good bond rating. The plant will include a fine-shredder, waste treatment facility, and a coal storage area. Pollution control will be handled by six oversized electrostatic precipitators, six mechanical dust collectors, and three 275-foot stacks. (DCK)

  9. Montenay recyclable trash improvements (RTI) project

    SciTech Connect

    Smith, D.M.; Smith, E.F.

    1998-07-01

    Municipal trash is converted to a solid fuel for an off-site boiler installation. Existing Miami-Dade Resources Recovery Facilities were modified and new processing facilities were added at a cost of $26 million dollars. This major recycling project was developed over three years, was built in 1996 and was successfully commissioned in 1997. Process machinery includes three modified shredders with a final throughput capacity of 110 tons per hour, conveyors, trommels, and raw product separation equipment. The RTI process makes commercial grade biomass fuel and two soil products. A discussion of process design and testing is presented. Other bulk material handling issues such as delivery contracts for raw trash ad remote site fuel delivery is included. Elements of the plant designs for truck tipping, rejects separation, process and storage buildings are also discussed.

  10. [Leaf litter decomposition in six Cloud Forest streams of the upper La Antigua watershed, Veracruz, Mexico].

    PubMed

    Astudillo, Manuel R; Ramírez, Alonso; Novelo-Gutiérrez, Rodolfo; Vázquez, Gabriela

    2014-04-01

    Leaf litter decomposition is an important stream ecosystem process. To understand factors controlling leaf decomposition in cloud forest in Mexico, we incubated leaf packs in different streams along a land use cover gradient for 35 days during the dry and wet seasons. We assessed relations between leaf decomposition rates (k), stream physicochemistry, and macroinvertebrates colonizing leaf packs. Physicochemical parameters showed a clear seasonal difference at all study streams. Leaves were colonized by collector-gatherer insects, followed by shredders. Assessment of factors related to k indicated that only forest cover was negatively related to leaf decomposition rates. Thus stream physicochemistry and seasonality had no impact on decomposition rates. We concluded that leaf litter decomposition at our study streams is a stable process over the year. However, it is possible that this stability is the result of factors regulating decomposition during the different seasons and streams.

  11. Upgrading mixed polyolefin waste with magnetic density separation.

    PubMed

    Bakker, E J; Rem, P C; Fraunholcz, N

    2009-05-01

    Polyolefin fractions are often end fractions resulting from the recycling of end-of-life consumer products. Polypropylene (PP) and polyethylene (PE) are present in such fractions as a mixture. For instance, the ratio of PP and PE in car scrap is 70:30 on average. However, the grade of the PP and PE should typically be better than 97% to be reused again as a high quality product. Density separation of the different polyolefins can be a solution. A promising separation technique is the inverse magnetic density separator (IMDS). This paper discusses the potential of shredder residue, one of the possible polyolefin's waste stream sources for the IMDS, in detail. Experiments with the separation of polyolefins with an IMDS prototype show both high grade and high recovery. The paper concludes with the economic opportunities of the IMDS in the recycling of polyolefins. PMID:19128952

  12. Effects of oxygen, catalyst and PVC on the formation of PCDDs, PCDFs and dioxin-like PCBs in pyrolysis products of automobile residues.

    PubMed

    Joung, Hyun-Tae; Seo, Yong-Chil; Kim, Ki-Heon; Seo, Yong-Chan

    2006-11-01

    End-of-life vehicles are dismantled to recover reusable parts and then sent to a shredding facility for steel material recovery. The residue generated from the shredding process, so-called automobile shredder residue, is now being mostly disposed in landfill, however landfill will be prohibited in the near future. More recycling and energy recovery must be made by the regulation. The most appropriate method is the thermal treatment that will produce various forms of fuels and less volume of vitrified residue. In this research, an automobile shredder residue was simulated with considering the residue from a shredding factory based on the new vehicle and thermally treated by pyrolysis or gasification to observe the yields of gas, oil and char. In the temperature range of 400-800 degrees C, the yields of gas, oil, and char were 38.7-45.8%, 12.3-18.2%, and 36.0-49.0%, respectively. The optimum pyrolyzing temperature for more oil production was around 600 degrees C. Emission characteristics of the byproducts, PCDDs, PCDFs and dioxin-like PCBs were studied at the temperature of 600 degrees C. The analysis on the concentration and distribution of the isomers in various forms of the products were completed with and without oxygen, PVC, and catalytic metals, in order to observe how the existence of oxygen, PVC, and catalytic metals affect the formation of PCDDs, PCDFs, and dioxin-like PCBs from pyrolysis or gasification process. Without PVC, no PCDDs, PCDFs and dioxin-like PCBs were found in any products. PCDFs were predominant in any conditions. Catalyst and oxygen were found to affect to form more PCDDs, PCDFs, and dioxin-like PCBs. Effects of catalyst and oxygen on the byproduct formation seemed to be similar in oil and gas while that was different in char.

  13. The effects of spatial scale on breakdown of leaves in a tropical watershed.

    PubMed

    Rezende, Renan S; Petrucio, Mauricio M; Gonçalves, José F

    2014-01-01

    The objective was to assess the effects of natural variation in the physical structure of the environment on biological communities and on the processing of Eucalyptus cloeziana and Inga laurina and to identify the controlling factors at different scales along stream order gradients. The study area consisted of 14 sampling sites distributed within a tropical watershed (1st, 2nd, 3rd and 4th order streams replicated in 4 sub-basins). Our samples consisted of 3 g of leaves of E. cloeziana (high-quality) and I. laurina (low-quality) placed in 252 bags with 10mm mesh (measured by the chemical composition of the detritus). Four samples of each leaf type were collected periodically (three times) over a period of 75-125 days and washed on a sieve to separate the invertebrates. A series of leaf disks were cut to determine ash-free dry mass, polyphenol, lignin, cellulose, total microbial biomass and fungal biomass, and the remaining material was oven-dried to determine the dry weight. We performed analyses within and between spatial scales (regional and local) to assess which watershed scale was the more import determinant of the leaf breakdown rate (k). The microbial and shredder were most influenced at the local scale (stream order). Shredders were influenced by microorganisms, with stronger interactions between them than were found to drive the k at the local scale. Moreover, differences in the overall k and abiotic variables were more strongly influenced at the regional scale (sub-basin), showing that the study scale alters the response of the studied variables. We found higher k values at higher values of water velocity, dissolved oxygen and temperature, all of which accelerate biological metabolism in response to variations on the regional scale. Watersheds with warmer microclimates and streams with higher nutrient levels and oxygen could be accelerating the ecosystem metabolism, independent of the detritus quality.

  14. Simulating food web dynamics along a gradient: quantifying human influence.

    PubMed

    Jordán, Ferenc; Gjata, Nerta; Mei, Shu; Yule, Catherine M

    2012-01-01

    Realistically parameterized and dynamically simulated food-webs are useful tool to explore the importance of the functional diversity of ecosystems, and in particular relations between the dynamics of species and the whole community. We present a stochastic dynamical food web simulation for the Kelian River (Borneo). The food web was constructed for six different locations, arrayed along a gradient of increasing human perturbation (mostly resulting from gold mining activities) along the river. Along the river, the relative importance of grazers, filterers and shredders decreases with increasing disturbance downstream, while predators become more dominant in governing eco-dynamics. Human activity led to increased turbidity and sedimentation which adversely impacts primary productivity. Since the main difference between the study sites was not the composition of the food webs (structure is quite similar) but the strengths of interactions and the abundance of the trophic groups, a dynamical simulation approach seemed to be useful to better explain human influence. In the pristine river (study site 1), when comparing a structural version of our model with the dynamical model we found that structurally central groups such as omnivores and carnivores were not the most important ones dynamically. Instead, primary consumers such as invertebrate grazers and shredders generated a greater dynamical response. Based on the dynamically most important groups, bottom-up control is replaced by the predominant top-down control regime as distance downstream and human disturbance increased. An important finding, potentially explaining the poor structure to dynamics relationship, is that indirect effects are at least as important as direct ones during the simulations. We suggest that our approach and this simulation framework could serve systems-based conservation efforts. Quantitative indicators on the relative importance of trophic groups and the mechanistic modeling of eco

  15. Effects of Habitat Characteristics and Water Quality on Macroinvertebrate Communities along the Neversink Riverin Southeastern New York, 1991-2001

    USGS Publications Warehouse

    Ernst, Anne G.; Baldigo, Barry P.; Schuler, George E.; Apse, Colin D.; Carter, James L.; Lester, Gary T.

    2008-01-01

    The Neversink River, in the Catskill Mountains of southeastern New York State, feeds the Neversink Reservoir, which diverts 85 percent of the river?s flow to New York City. Acidification of several headwater reaches has affected macroinvertebrate assemblages throughout the river system above the reservoir, and the alteration of flow conditions below the reservoir dam has affected macroinvertebrate assemblages for at least 10 kilometers downstream from the reservoir. In 1999, the U.S. Geological Survey, in cooperation with The Nature Conservancy, compiled data from 30 stream reaches to quantify the effects of acidification and of the reservoir on the structure and function of macroinvertebrate assemblages throughout the Neversink River. Acidic headwater reaches supported greater numbers of acid-tolerant chironomid taxa and fewer numbers of acid-sensitive Ephemeroptera and Trichoptera than neutral reaches, and fewer scraper individuals and more shredder individuals. The 14 reaches below the reservoir, with sharply decreased flows and altered flow patterns compared to reaches above the reservoir, supported more Chironomidae and fewer Ephemeroptera and Trichoptera than the upper reaches; they also had greater numbers of shredder individuals and fewer scraper and filterer individuals than reaches above the reservoir. Water-quality variables such as pH and aluminum concentration appear to have affected macroinvertebrate assemblages more strongly in the headwaters than below the reservoir, whereas physical-habitat variables such as mean channel width and water temperature have affected these assemblages more strongly downstream from the reservoir than in the headwaters. The water-quality changes due to acidification, combined with the decreased flows and lowered water temperatures below the reservoir, have disrupted downstream continuum of macroinvertebrate communities that would normally be observed from the headwaters to the mouth. The information presented herein

  16. Exposure pathway-dependent effects of the fungicide epoxiconazole on a decomposer-detritivore system.

    PubMed

    Feckler, Alexander; Goedkoop, Willem; Zubrod, Jochen P; Schulz, Ralf; Bundschuh, Mirco

    2016-11-15

    Shredders play a central role in the breakdown of leaf material in aquatic systems. These organisms and the ecological function they provide may, however, be affected by chemical stressors either as a consequence of direct waterborne exposure or through alterations in food-quality (indirect pathway). To unravel the biological relevance of these effect pathways, we applied a 2×2-factorial test design. Leaf material was microbially colonized for 10days in absence or presence of the fungicide epoxiconazole (15μg/L) and subsequently fed to the shredder Asellus aquaticus under exposure to epoxiconazole (15μg/L) or in fungicide-free medium over a 28-day period (n=40). Both effect pathways caused alterations in asselids' food processing, physiological fitness, and growth, although not always statistically significantly: assimilation either increased or remained at a similar level relative to the control suggesting compensatory behavior of A. aquaticus to cope with the enhanced energy demand for detoxification processes and decreased nutritional quality of the food. The latter was driven by lowered microbial biomasses and the altered composition of fatty acids associated with the leaf material. Even with increased assimilation, direct and indirect effects caused decreases in the growth and lipid (fatty acid) content of A. aquaticus with relative effect sizes between 10 and 40%. Moreover, the concentrations of two essential polyunsaturated fatty acids (i.e., arachidonic acid and eicosapentaenoic acid) were non-significantly reduced (up to ~15%) in asselids. This effect was, however, independent of the exposure pathway. Although waterborne effects were generally stronger than the diet-related effects, results suggest impaired functioning of A. aquaticus via both effect pathways. PMID:27450951

  17. Multi-trophic resilience of boreal lake ecosystems to forest fires

    USGS Publications Warehouse

    Lewis, Tyler L.; Lindberg, Mark S.; Schmutz, Joel A.; Bertram, M.R.

    2014-01-01

    Fires are the major natural disturbance in the boreal forest, and their frequency and intensity will likely increase as the climate warms. Terrestrial nutrients released by fires may be transported to boreal lakes, stimulating increased primary productivity, which may radiate through multiple trophic levels. Using a before-after-control-impact (BACI) design, with pre- and postfire data from burned and unburned areas, we examined effects of a natural fire across several trophic levels of boreal lakes, from nutrient and chlorophyll levels, to macroinvertebrates, to waterbirds. Concentrations of total nitrogen and phosphorus were not affected by the fire. Chlorophyll levels were also unaffected, likely reflecting the stable nutrient concentrations. For aquatic invertebrates, we found that densities of three functional feeding groups did not respond to the fire (filterers, gatherers, scrapers), while two groups increased (shredders, predators). Amphipods accounted for 98% of shredder numbers, and we hypothesize that fire-mediated habitat changes may have favored their generalist feeding and habitat ecology. This increase in amphipods may, in turn, have driven increased predator densities, as amphipods were the most numerous invertebrate in our lakes and are commonly taken as prey. Finally, abundance of waterbird young, which feed primarily on aquatic invertebrates, was not affected by the fire. Overall, ecosystems of our study lakes were largely resilient to forest fires, likely due to their high initial nutrient concentrations and small catchment sizes. Moreover, this resilience spanned multiple trophic levels, a significant result for ecologically similar boreal regions, especially given the high potential for increased fires with future climate change.

  18. Multi-trophic resilience of boreal lake ecosystems to forest fires.

    PubMed

    Lewis, Tyler L; Lindberg, Mark S; Schmutz, Joel A; Bertram, Mark R

    2014-05-01

    Fires are the major natural disturbance in the boreal forest, and their frequency and intensity will likely increase as the climate warms. Terrestrial nutrients released by fires may be transported to boreal lakes, stimulating increased primary productivity, which may radiate through multiple trophic levels. Using a before-after-control-impact (BACI) design, with pre- and postfire data from burned and unburned areas, we examined effects of a natural fire across several trophic levels of boreal lakes, from nutrient and chlorophyll levels, to macroinvertebrates, to waterbirds. Concentrations of total nitrogen and phosphorus were not affected by the fire. Chlorophyll a levels were also unaffected, likely reflecting the stable nutrient concentrations. For aquatic invertebrates, we found that densities of three functional feeding groups did not respond to the fire (filterers, gatherers, scrapers), while two groups increased (shredders, predators). Amphipods accounted for 98% of shredder numbers, and we hypothesize that fire-mediated habitat changes may have favored their generalist feeding and habitat ecology. This increase in amphipods may, in turn, have driven increased predator densities, as amphipods were the most numerous invertebrate in our lakes and are commonly taken as prey. Finally, abundance of waterbird young, which feed primarily on aquatic invertebrates, was not affected by the fire. Overall, ecosystems of our study lakes were largely resilient to forest fires, likely due to their high initial nutrient concentrations and small catchment sizes. Moreover, this resilience spanned multiple trophic levels, a significant result for ecologically similar boreal regions, especially given the high potential for increased fires with future climate change.

  19. Simulating food web dynamics along a gradient: quantifying human influence.

    PubMed

    Jordán, Ferenc; Gjata, Nerta; Mei, Shu; Yule, Catherine M

    2012-01-01

    Realistically parameterized and dynamically simulated food-webs are useful tool to explore the importance of the functional diversity of ecosystems, and in particular relations between the dynamics of species and the whole community. We present a stochastic dynamical food web simulation for the Kelian River (Borneo). The food web was constructed for six different locations, arrayed along a gradient of increasing human perturbation (mostly resulting from gold mining activities) along the river. Along the river, the relative importance of grazers, filterers and shredders decreases with increasing disturbance downstream, while predators become more dominant in governing eco-dynamics. Human activity led to increased turbidity and sedimentation which adversely impacts primary productivity. Since the main difference between the study sites was not the composition of the food webs (structure is quite similar) but the strengths of interactions and the abundance of the trophic groups, a dynamical simulation approach seemed to be useful to better explain human influence. In the pristine river (study site 1), when comparing a structural version of our model with the dynamical model we found that structurally central groups such as omnivores and carnivores were not the most important ones dynamically. Instead, primary consumers such as invertebrate grazers and shredders generated a greater dynamical response. Based on the dynamically most important groups, bottom-up control is replaced by the predominant top-down control regime as distance downstream and human disturbance increased. An important finding, potentially explaining the poor structure to dynamics relationship, is that indirect effects are at least as important as direct ones during the simulations. We suggest that our approach and this simulation framework could serve systems-based conservation efforts. Quantitative indicators on the relative importance of trophic groups and the mechanistic modeling of eco

  20. Structure solution with ARCIMBOLDO using fragments derived from distant homology models.

    PubMed

    Sammito, Massimo; Meindl, Kathrin; de Ilarduya, Iñaki M; Millán, Claudia; Artola-Recolons, Cecilia; Hermoso, Juan A; Usón, Isabel

    2014-09-01

    Molecular replacement, one of the general methods used to solve the crystallographic phase problem, relies on the availability of suitable models for placement in the unit cell of the unknown structure in order to provide initial phases. ARCIMBOLDO, originally conceived for ab initio phasing, operates at the limit of this approach, using small, very accurate fragments such as polyalanine α-helices. A distant homolog may contain accurate building blocks, but it may not be evident which sub-structure is the most suitable purely from the degree of conservation. Trying out all alternative possibilities in a systematic way is computationally expensive, even if effective. In the present study, the solution of the previously unknown structure of MltE, an outer membrane-anchored endolytic peptidoglycan lytic transglycosylase from Escherichia coli, is described. The asymmetric unit contains a dimer of this 194 amino acid protein. The closest available homolog was the catalytic domain of Slt70 (PDB code 1QTE). Originally, this template was used omitting contiguous spans of aminoacids and setting as many ARCIMBOLDO runs as models, each aiming to locate two copies sequentially with PHASER. Fragment trimming against the correlation coefficient prior to expansion through density modification and autotracing in SHELXE was essential. Analysis of the figures of merit led to the strategy to optimize the search model against the experimental data now implemented within ARCIMBOLDO-SHREDDER (http://chango.ibmb.csic.es/SHREDDER). In this strategy, the initial template is systematically shredded, and fragments are scored against each unique solution of the rotation function. Results are combined into a score per residue and the template is trimmed accordingly.

  1. Macroinvertebrate assemblage recovery following a catastrophic flood and debris flows in an Appalachian mountain stream

    USGS Publications Warehouse

    Snyder, C.D.; Johnson, Z.B.

    2006-01-01

    In June 1995, heavy rains caused severe flooding and massive debris flows on the Staunton River, a 3rd-order stream in the Blue Ridge Mountains (Virginia, USA). Scouring caused the loss of the riparian zone and repositioned the stream channel of the lower 2.1 km of the stream. Between 1998 and 2001, we conducted seasonal macroinvertebrate surveys at sites on the Staunton River and on White Oak Canyon Run, a reference stream of similar size and geology that was relatively unaffected by the flood. Our study was designed to determine the extent to which flood-induced changes to the stream channel and riparian habitats caused long-term changes to macroinvertebrate community structure and composition. Sites within the impacted zone of the Staunton River supported diverse stable benthic macroinvertebrate assemblages 3 y after the flood despite dramatic and persistent changes in environmental factors known to be important controls on stream ecosystem function. However, significant differences in total macroinvertebrate density and trophic structure could be attributed to the flood. In autumn, densities of most feeding guilds, including shredders, were higher at impacted-zone sites than at all other sites, suggesting higher overall productivity in the impacted zone. Higher shredder density in the impacted zone was surprising in light of expected decreases in leaf-litter inputs because of removal of riparian forests. In contrast, in spring, we observed density differences in only one feeding guild, scrapers, which showed higher densities at impacted-zone sites than at all other sites. This result conformed to a priori expectations that reduced shading in the impacted zone would lead to increased light and higher instream primary production. We attribute the seasonal differences in trophic structure to the effects of increased temperatures on food quality and to the relationship between the timing of our sampling and the emergence patterns of important taxa. ?? 2006 by The

  2. Controlled combustion tests and bottom ash analysis using household waste with varying composition

    SciTech Connect

    Hu Yanjun; Bakker, Maarten; Brem, Gerrit; Chen Guanyi

    2011-02-15

    The influence of the co-combustion of household waste with either sewage sludge, shredder fluff, electronic and electrical waste (WEEE) or PVC on the bottom ash quality and content was investigated under controlled laboratory conditions using a pot furnace. This laboratory approach avoids the interpretation problems related to large variations in input waste composition and combustion conditions that are observed in large scale MSW incinerators. The data for metals content, transfer coefficients and leaching values are presented relative to data for a base household waste composition that did not contain any of the added special wastes. The small WEEE invited direct measurement of precious metals content in the ashes, where measurement accuracy is facilitated by using only mobile phone scrap for small WEEE. The analyses were carried out for different particle size ranges that are of relevance to the recyclability of metals and minerals in the ashes. Positive correlations were found between elements content of the input waste and the bottom ashes, and also between increased levels of Cl, Mo and Cu in the input waste and their leaching in the bottom ashes. These correlations indicate that addition of PVC, small WEEE and shredder fluff in input waste can have a negative influence on the quality of the bottom ashes. Enrichment of Au and Ag occurred in the fractions between 0.15 and 6 mm. The precious metals content represents an economically interesting intrinsic value, even when the observed peak values are properly averaged over a larger volume of ashes. Overall, it has been shown that changes in quality and content of bottom ashes may be traced back to the varied input waste composition.

  3. The Effects of Spatial Scale on Breakdown of Leaves in a Tropical Watershed

    PubMed Central

    Rezende, Renan S.; Petrucio, Mauricio M.; Gonçalves, José F.

    2014-01-01

    The objective was to assess the effects of natural variation in the physical structure of the environment on biological communities and on the processing of Eucalyptus cloeziana and Inga laurina and to identify the controlling factors at different scales along stream order gradients. The study area consisted of 14 sampling sites distributed within a tropical watershed (1st, 2nd, 3rd and 4th order streams replicated in 4 sub-basins). Our samples consisted of 3 g of leaves of E. cloeziana (high-quality) and I. laurina (low-quality) placed in 252 bags with 10mm mesh (measured by the chemical composition of the detritus). Four samples of each leaf type were collected periodically (three times) over a period of 75–125 days and washed on a sieve to separate the invertebrates. A series of leaf disks were cut to determine ash-free dry mass, polyphenol, lignin, cellulose, total microbial biomass and fungal biomass, and the remaining material was oven-dried to determine the dry weight. We performed analyses within and between spatial scales (regional and local) to assess which watershed scale was the more import determinant of the leaf breakdown rate (k). The microbial and shredder were most influenced at the local scale (stream order). Shredders were influenced by microorganisms, with stronger interactions between them than were found to drive the k at the local scale. Moreover, differences in the overall k and abiotic variables were more strongly influenced at the regional scale (sub-basin), showing that the study scale alters the response of the studied variables. We found higher k values at higher values of water velocity, dissolved oxygen and temperature, all of which accelerate biological metabolism in response to variations on the regional scale. Watersheds with warmer microclimates and streams with higher nutrient levels and oxygen could be accelerating the ecosystem metabolism, independent of the detritus quality. PMID:24810918

  4. Wetland macroinvertebrates of Prentiss Bay, Lake Huron, Michigan: diversity and functional group composition

    USGS Publications Warehouse

    Merritt, R.W.; Benbow, M.E.; Hudson, P.L.

    2002-01-01

    The Great Lakes support many fish and waterbirds that depend directly or indirectly on coastal wetlands during some portion of their life cycle. It is known that macroinvertebrates make up an important part of wetland food webs and ecosystem function; however, our understanding of species distribution within and among wetlands has only recently received attention. We investigated the macroinvertebrates of a freshwater marsh (Prentiss Bay) in the Les Chenaux Island Area of Northern Lake Huron, Michigan. Macroinvertebrate taxa diversity and functional feeding group composition were compared between two habitats. A shallow depositional habitat with higher vegetation diversity and little wave action was compared to a deeper erosional habitat with fewer plant species and more wave action. A total of 83 taxa were collected over the summer of 1996, representing two phyla (Arthropoda and Mollusca) and five classes (Arachnida, Bivalvia, Malacostraca, Gastropoda and Insecta). A total of 79 genera were identified, with 92% being insects (39 families composed of at least 73 genera). Of the total, 42 insect genera were common to both habitats,while relatively fewer were collected exclusively from the erosional compared the depositional habitat. When habitats were pooled, predators comprised about 50% of the functional group taxa, while gathering collectors and shredders each were about 20%. Filtering collectors and scrapers each represented < 10%. When comparing habitats, there was a relatively higher percentage of predators and shredders in the depositional habitat, while all other functional groups were lower. These data suggest that vegetation diversity, depth and wave action affect taxa composition and functional group organization of the Prentiss Bay marsh.

  5. Aquatic insect community structure under the influence of small dams in a stream of the Mogi-Guaçu river basin, state of São Paulo.

    PubMed

    Saulino, H H L; Corbi, J J; Trivinho-Strixino, S

    2014-02-01

    The fragmentation of lotic systems caused by construction of dams has modified many aquatic communities. The objective of this study was to analyse changes in the aquatic insect community structure by discontinuity of habitat created by dams along the Ribeirão das Anhumas, a sub-basin of the Mogi-Guaçu River (state of São Paulo, Brazil). Entomofauna collection was carried out in 10 segments upstream and downstream of five dams along the longitudinal profile of the stream, with a quick sampling method using a D net (mesh 250 mm) with 2 minutes of sampling effort. The insects were sorted and identified to the lowest possible taxonomic level and analysed by the Shannon diversity index, β diversity, richness estimated by rarefaction curves and relative participation of functional feeding groups. The results showed a slight reduction in diversity in the downstream segments, as well as along the longitudinal profile of the stream. However, there were no significant differences in abundance and richness between the upstream and downstream segments, indicating that the dams did not influence these variables. Differences were observed in the functional feeding groups along the longitudinal profile. Predator and gatherer insects were dominant in all segments analysed. The feeding group of shredders was more abundant in the segment DSIII with the participation of Marilia Müller (Odontoceridae - Trichoptera), although we observed a decrease of shredders and scrapers with the decrease of the canopy cover reducing values of β diversity in the continuum of Ribeirão das Anhumas. This result demonstrated the importance of the conservation of the riparian vegetation in order to maintain the integrity of the stream. PMID:25055089

  6. Multi-trophic resilience of boreal lake ecosystems to forest fires.

    PubMed

    Lewis, Tyler L; Lindberg, Mark S; Schmutz, Joel A; Bertram, Mark R

    2014-05-01

    Fires are the major natural disturbance in the boreal forest, and their frequency and intensity will likely increase as the climate warms. Terrestrial nutrients released by fires may be transported to boreal lakes, stimulating increased primary productivity, which may radiate through multiple trophic levels. Using a before-after-control-impact (BACI) design, with pre- and postfire data from burned and unburned areas, we examined effects of a natural fire across several trophic levels of boreal lakes, from nutrient and chlorophyll levels, to macroinvertebrates, to waterbirds. Concentrations of total nitrogen and phosphorus were not affected by the fire. Chlorophyll a levels were also unaffected, likely reflecting the stable nutrient concentrations. For aquatic invertebrates, we found that densities of three functional feeding groups did not respond to the fire (filterers, gatherers, scrapers), while two groups increased (shredders, predators). Amphipods accounted for 98% of shredder numbers, and we hypothesize that fire-mediated habitat changes may have favored their generalist feeding and habitat ecology. This increase in amphipods may, in turn, have driven increased predator densities, as amphipods were the most numerous invertebrate in our lakes and are commonly taken as prey. Finally, abundance of waterbird young, which feed primarily on aquatic invertebrates, was not affected by the fire. Overall, ecosystems of our study lakes were largely resilient to forest fires, likely due to their high initial nutrient concentrations and small catchment sizes. Moreover, this resilience spanned multiple trophic levels, a significant result for ecologically similar boreal regions, especially given the high potential for increased fires with future climate change. PMID:25000757

  7. Effects of oxygen, catalyst and PVC on the formation of PCDDs, PCDFs and dioxin-like PCBs in pyrolysis products of automobile residues.

    PubMed

    Joung, Hyun-Tae; Seo, Yong-Chil; Kim, Ki-Heon; Seo, Yong-Chan

    2006-11-01

    End-of-life vehicles are dismantled to recover reusable parts and then sent to a shredding facility for steel material recovery. The residue generated from the shredding process, so-called automobile shredder residue, is now being mostly disposed in landfill, however landfill will be prohibited in the near future. More recycling and energy recovery must be made by the regulation. The most appropriate method is the thermal treatment that will produce various forms of fuels and less volume of vitrified residue. In this research, an automobile shredder residue was simulated with considering the residue from a shredding factory based on the new vehicle and thermally treated by pyrolysis or gasification to observe the yields of gas, oil and char. In the temperature range of 400-800 degrees C, the yields of gas, oil, and char were 38.7-45.8%, 12.3-18.2%, and 36.0-49.0%, respectively. The optimum pyrolyzing temperature for more oil production was around 600 degrees C. Emission characteristics of the byproducts, PCDDs, PCDFs and dioxin-like PCBs were studied at the temperature of 600 degrees C. The analysis on the concentration and distribution of the isomers in various forms of the products were completed with and without oxygen, PVC, and catalytic metals, in order to observe how the existence of oxygen, PVC, and catalytic metals affect the formation of PCDDs, PCDFs, and dioxin-like PCBs from pyrolysis or gasification process. Without PVC, no PCDDs, PCDFs and dioxin-like PCBs were found in any products. PCDFs were predominant in any conditions. Catalyst and oxygen were found to affect to form more PCDDs, PCDFs, and dioxin-like PCBs. Effects of catalyst and oxygen on the byproduct formation seemed to be similar in oil and gas while that was different in char. PMID:16740293

  8. Chlorinated and parent polycyclic aromatic hydrocarbons in environmental samples from an electronic waste recycling facility and a chemical industrial complex in China.

    PubMed

    Ma, Jing; Horii, Yuichi; Cheng, Jinping; Wang, Wenhua; Wu, Qian; Ohura, Takeshi; Kannan, Kurunthachalam

    2009-02-01

    Chlorinated polycyclic aromatic hydrocarbons (CIPAHs) are a class of halogenated contaminants found in the urban atmosphere; they have toxic potential similar to that of dioxins. Information on the sources of CIPAHs is limited. In this study, concentrations of 20 CIPAHs and 16 parent PAHs were measured in electronic wastes, workshop-floor dust, vegetation, and surface soil collected from the vicinity of an electronic waste (e-waste) recycling facility and in surface soil from a chemical industrial complex (comprising a coke-oven plant, a coal-fired power plant, and a chlor-alkali plant), and agricultural areas in central and eastern China. High concentrations of SigmaCIPAHs were found in floor dust (mean, 103 ng/g dry wt), followed in order of decreasing concentration by leaves (87.5 ng/g drywt), electronic shredder waste (59.1 ng/g dry wt), and soil (26.8 ng/g dry wt) from an e-waste recycling facility in Taizhou. The mean concentration of SigmaCIPAHs in soil from the chemical industrial complex (88 ng/g dry wt) was approximately 3-fold higher than the concentration in soil from e-waste recycling facilities. The soils from e-waste sites and industrial areas contained mean concentrations of SigmaCIPAHs 2 to 3 orders of magnitude higher than the concentrations in agricultural soils (ND-0.76 ng/g), suggesting that e-waste recycling and chlorine-chemical industries are potential emission sources of CIPAHs. The profiles of CIPAHs in soil and dust were similar to a profile that has been reported previously for fly ash from municipal solid waste incinerators (6-CIBaP was the predominant compound), but the profiles in vegetation and electronic shredder waste were different from those found in fly ash. Concentrations of 16 parent PAHs were high (150-49,700 ng/g) in samples collected from the e-waste recycling facility. Significant correlation between SigmaCIPAH and SigmaPAH concentrations suggests that direct chlorination of parent PAHs is the major pathway of formation of

  9. Effects of Eucalyptus plantations on detritus, decomposers, and detritivores in streams.

    PubMed

    Graça, Manuel A S; Pozo, Jesús; Canhoto, Cristina; Elosegi, Arturo

    2002-04-30

    retarded or suppressed fungal growth. Streams bordered by Eucalyptus had lower diversity of fungal spores (but similar spore densities) in Portugal; less consistent patterns were found in similar experiments in Spain. Eucalyptus leaves proved to be poor food for shredders. Under laboratory conditions leaves of Eucalyptus ranked low in food selection experiments using native shredders. The same shredders failed to grow and died when fed exclusively eucalypt leaves. The removal of oils from eucalypt leaves resulted in increased feeding rates, whereas the transfer of oils to alder leaves resulted in decreased feeding rates. The effect of eucalypt plantations on stream invertebrate communities is not very consistent. In nutrient-poor waters, fewer invertebrates colonized eucalypt than alder leaves, but this effect was mitigated after a microbial conditioning period in nutrient-rich waters. Portuguese streams bordered by Eucalyptus had lower numbers of invertebrates than streams surrounded by deciduous forests. In Spanish streams differences were less marked and nonexistent when looking at the composition of the communities, which change more from year to year than from site to site. Most of the eucalypt streams studied in Portugal and Spain dried up in summer, a fact that might reflect an increase in soil hydrophobity produced by Eucalyptus plantations. The very short planting-to-harvest period of eucalypt plantations results in additional impacts, such as soil loss, siltation of streams, or reduced amounts of woody debris in stream channels, which affects their capacity to retain leaf-litter, as well as the availability of habitat for invertebrates and fish. The studies by the Portuguese and Spanish research teams confirm the importance of maintaining riparian buffer strips to reduce human impact on streams and rivers. PMID:12805976

  10. Effects of Eucalyptus plantations on detritus, decomposers, and detritivores in streams.

    PubMed

    Graça, Manuel A S; Pozo, Jesús; Canhoto, Cristina; Elosegi, Arturo

    2002-04-30

    retarded or suppressed fungal growth. Streams bordered by Eucalyptus had lower diversity of fungal spores (but similar spore densities) in Portugal; less consistent patterns were found in similar experiments in Spain. Eucalyptus leaves proved to be poor food for shredders. Under laboratory conditions leaves of Eucalyptus ranked low in food selection experiments using native shredders. The same shredders failed to grow and died when fed exclusively eucalypt leaves. The removal of oils from eucalypt leaves resulted in increased feeding rates, whereas the transfer of oils to alder leaves resulted in decreased feeding rates. The effect of eucalypt plantations on stream invertebrate communities is not very consistent. In nutrient-poor waters, fewer invertebrates colonized eucalypt than alder leaves, but this effect was mitigated after a microbial conditioning period in nutrient-rich waters. Portuguese streams bordered by Eucalyptus had lower numbers of invertebrates than streams surrounded by deciduous forests. In Spanish streams differences were less marked and nonexistent when looking at the composition of the communities, which change more from year to year than from site to site. Most of the eucalypt streams studied in Portugal and Spain dried up in summer, a fact that might reflect an increase in soil hydrophobity produced by Eucalyptus plantations. The very short planting-to-harvest period of eucalypt plantations results in additional impacts, such as soil loss, siltation of streams, or reduced amounts of woody debris in stream channels, which affects their capacity to retain leaf-litter, as well as the availability of habitat for invertebrates and fish. The studies by the Portuguese and Spanish research teams confirm the importance of maintaining riparian buffer strips to reduce human impact on streams and rivers.

  11. Quantitative transfer of Escherichia coli O157:H7 to equipment during small-scale production of fresh-cut leafy greens.

    PubMed

    Buchholz, Annemarie L; Davidson, Gordon R; Marks, Bradley P; Todd, Ewen C D; Ryser, Elliot T

    2012-07-01

    Postharvest contamination and subsequent spread of Escherichia coli O157:H7 can occur during shredding, conveying, fluming, and dewatering of fresh-cut leafy greens. This study quantified E. coli O157:H7 transfer from leafy greens to equipment surfaces during simulated small-scale commercial processing. Three to five batches (22.7 kg) of baby spinach, iceberg lettuce, and romaine lettuce were dip inoculated with a four-strain cocktail of avirulent, green fluorescent protein-labeled, ampicillinresistant E. coli O157:H7 to contain ∼10(6), 10(4), and 10(2) CFU/g, and then were processed after 1 h of draining at ∼23°C or 24 h of storage at 4°C. Lettuce was shredded using an Urschel TransSlicer at two different blade and belt speeds to obtain normal (5 by 5 cm) and more finely shredded (0.5 by 5 cm) lettuce. Thereafter, the lettuce was step conveyed to a flume tank and was washed and then dried using a shaker table and centrifugal dryer. Product (25-g) and water (40-ml) samples were collected at various points during processing. After processing, product contact surfaces (100 cm(2)) on the shredder (n = 14), conveyer (n = 8), flume tank (n = 11), shaker table (n = 9), and centrifugal dryer (n = 8) were sampled using one-ply composite tissues. Sample homogenates diluted in phosphate or neutralizing buffer were plated, with or without prior 0.45- m m membrane filtration, on Trypticase soy agar containing 0.6% yeast extract supplemented with 100 ppm of ampicillin to quantify green fluorescent protein-labeled E. coli O157:H7 under UV light. During leafy green processing, ∼90% of the E. coli O157:H7 inoculum transferred to the wash water. After processing, E. coli O157:H7 populations were highest on the conveyor and shredder (P<0.05), followed by the centrifugal dryer, flume tank, and shaker table, with ∼29% of the remaining product inoculum lost during centrifugal drying. Overall, less (P<0.05) of the inoculum remained on the product after centrifugally drying

  12. Transfer of Escherichia coli O157:H7 from equipment surfaces to fresh-cut leafy greens during processing in a model pilot-plant production line with sanitizer-free water.

    PubMed

    Buchholz, Annemarie L; Davidson, Gordon R; Marks, Bradley P; Todd, Ewen C D; Ryser, Elliot T

    2012-11-01

    Escherichia coli O157:H7 contamination of fresh-cut leafy greens has become a public health concern as a result of several large outbreaks. The goal of this study was to generate baseline data for E. coli O157:H7 transfer from product-inoculated equipment surfaces to uninoculated lettuce during pilot-scale processing without a sanitizer. Uninoculated cored heads of iceberg and romaine lettuce (22.7 kg) were processed using a commercial shredder, step conveyor, 3.3-m flume tank with sanitizer-free tap water, shaker table, and centrifugal dryer, followed by 22.7 kg of product that had been dip inoculated to contain ∼10(6), 10(4), or 10(2) CFU/g of a four-strain avirulent, green fluorescent protein-labeled, ampicillin-resistant E. coli O157:H7 cocktail. After draining the flume tank and refilling the holding tank with tap water, 90.8 kg of uninoculated product was similarly processed and collected in ∼5-kg aliquots. After processing, 42 equipment surface samples and 46 iceberg or 36 romaine lettuce samples (25 g each) from the collection baskets were quantitatively examined for E. coli O157:H7 by direct plating or membrane filtration using tryptic soy agar containing 0.6% yeast extract and 100 ppm of ampicillin. Initially, the greatest E. coli O157:H7 transfer was seen from inoculated lettuce to the shredder and conveyor belt, with all equipment surface populations decreasing 90 to 99% after processing 90.8 kg of uncontaminated product. After processing lettuce containing 10(6) or 10(4) E. coli O157:H7 CFU/g followed by uninoculated lettuce, E. coli O157:H7 was quantifiable throughout the entire 90.8 kg of product. At an inoculation level of 10(2) CFU/g, E. coli O157:H7 was consistently detected in the first 21.2 kg of previously uninoculated lettuce at 2 to 3 log CFU/100 g and transferred to 78 kg of product. These baseline E. coli O157:H7 transfer results will help determine the degree of sanitizer efficacy required to better ensure the safety of fresh-cut leafy

  13. Concentrations, profiles, and estimated human exposures for polychlorinated dibenzo-p-dioxins and dibenzofurans from electronic waste recycling facilities and a chemical industrial complex in Eastern China

    SciTech Connect

    Ma, J.; Kannan, K.; Cheng, J.; Horii, Y.; Wu, Q.; Wang, W.

    2008-11-15

    Electronic shredder waste and dust from e-waste facilities, and leaves and surface soil collected in the vicinity of a large scale e-waste recycling facility in Taizhou, Eastern China, were analyzed for total dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) including 2,3,7,8-substituted congeners. We also determined PCDD/Fs in surface agricultural soils from several provinces in China for comparison with soils from e-waste facilities. Concentrations of total PCDD/Fs were high in all of the matrices analyzed and ranged from 30.9 to 11,400 pg/g for shredder waste, 3460 to 9820 pg/g dry weight for leaves, 2560 to 148,000 pg/g dry weight for workshop-floor dust, and 854 to 10200 pg/g dry weight for soils. We also analyzed surface soils from a chemical industrial complex (a coke-oven plant, a coal-fired power plant, and a chlor-alkali plant) in Shanghai. Concentrations of total PCDD/Fs in surface soil from the chemical industrial complex were lower than the concentrations found in soils from e-waste recycling plants, but higher than the concentrations found in agricultural soils. Agricultural soils from six cities in China contained low levels of total PCDD/Fs. Profiles of dioxin toxic equivalents (TEQs) of 2,3,7,8-PCDD/Fs in soils from e-waste facilities in Taizhou differed from the profiles found in agricultural soils. The estimated daily intakes of TEQs of PCDD/Fs via soil/dust ingestion and dermal exposure were 2 orders of magnitude higher in people at e-waste recycling facilities than in people at the chemical industrial site, implying greater health risk for humans from dioxin exposures at e-waste recycling facilities. The calculated TEQ exposures for e-waste workers from dust and soil ingestion alone were 2-3 orders of magnitude greater than the exposures from soils in reference locations. 37 refs., 1 fig., 2 tabs.

  14. Tracking an Escherichia coli O157:H7-contaminated batch of leafy greens through a pilot-scale fresh-cut processing line.

    PubMed

    Buchholz, Annemarie L; Davidson, Gordon R; Marks, Bradley P; Todd, Ewen C D; Ryser, Elliot T

    2014-09-01

    Cross-contamination of fresh-cut leafy greens with residual Escherichia coli O157:H7-contaminated product during commercial processing was likely a contributing factor in several recent multistate outbreaks. Consequently, radicchio was used as a visual marker to track the spread of the contaminated product to iceberg lettuce in a pilot-scale processing line that included a commercial shredder, step conveyor, flume tank, shaker table, and centrifugal dryer. Uninoculated iceberg lettuce (45 kg) was processed, followed by 9.1 kg of radicchio (dip inoculated to contain a four-strain, green fluorescent protein-labeled nontoxigenic E. coli O157:H7 cocktail at 10(6) CFU/g) and 907 kg (2,000 lb) of uninoculated iceberg lettuce. After collecting the lettuce and radicchio in about 40 bags (∼22.7 kg per bag) along with water and equipment surface samples, all visible shreds of radicchio were retrieved from the bags of shredded product, the equipment, and the floor. E. coli O157:H7 populations were quantified in the lettuce, water, and equipment samples by direct plating with or without prior membrane filtration on Trypticase soy agar containing 0.6% yeast extract and 100 ppm of ampicillin. Based on triplicate experiments, the weight of radicchio in the shredded lettuce averaged 614.9 g (93.6%), 6.9 g (1.3%), 5.0 g (0.8%), and 2.8 g (0.5%) for bags 1 to 10, 11 to 20, 21 to 30, and 31 to 40, respectively, with mean E. coli O157:H7 populations of 1.7, 1.2, 1.1, and 1.1 log CFU/g in radicchio-free lettuce. After processing, more radicchio remained on the conveyor (9.8 g; P < 0.05), compared with the shredder (8.3 g), flume tank (3.5 g), and shaker table (0.1 g), with similar E. coli O157:H7 populations (P > 0.05) recovered from all equipment surfaces after processing. These findings clearly demonstrate both the potential for the continuous spread of contaminated lettuce to multiple batches of product during processing and the need for improved equipment designs that minimize

  15. On-field investigation and process modelling of end-of-life vehicles treatment in the context of Italian craft-type authorized treatment facilities.

    PubMed

    Berzi, Lorenzo; Delogu, Massimo; Giorgetti, Alessandro; Pierini, Marco

    2013-04-01

    The present article analyses the current situation of End-of-Life-of-Vehicles (ELVs) management in Europe, with particular attention on Italian condition. Similarly to other European countries, metal recycling is the main activity of the whole system, but such situation is evolving due to the 2000/53/EC Directive, which sets out targets for Reuse, Recycling and Recovery of ELVs. Due to the relevance of the ELVs problem, in 2008 Italian Ministry of Environment subscribed a framework agreement with competent stakeholders as carmakers, dismantlers, shredders. The main result is an industrial plan to promote (amongst other objectives) technological progress for residual waste (Automotive Shredder Residue-ASR) treatment. According with Italian Trial 2006 analysis about ELVs, Reuse and Recycling rate is currently estimated to be about 81%. At the present time, dismantling plants constitute the first collection points for ELVs; for this reason, during 2009 an investigation has been done over a number of ten Authorized Treatment Facilities (ATFs) operating in Italy. The first step of the analysis was aimed to find out major practices and methods through observations of ATFs activities and interviews to operators. Furthermore, the depollution and dismantling treatments of about 70 different ELVs have been observed and timed in detail over a period of three months. The results included the identification of most relevant critical issues in ELVs treatment, such as distortions between scrapping activities and Directive's regulation, and the assessment of the time and of the resources needed to perform each operation. In the second step of the survey, a process simulation model has been built on the basis of such data. The model was aimed to include the real variability and all the uncertainties that are typical of dismantling activities; it is intended as a tool for process layout planning and for its management. Some control parameters have been introduced; these are able to

  16. The assemblage characteristics of benthic macroinvertebrates in the Yalutsangpo River, the highest major river in the world

    NASA Astrophysics Data System (ADS)

    Xu, Mengzhen; Wang, Zhaoyin; Pan, Baozhu; Yu, Guoan

    2014-09-01

    Aquatic ecosystems of highland rivers are different from those of low altitude rivers because of the specific topography and environmental parameters associated with high altitudes. Yalutsangpo, the upper course of the Brahmaputra River, is the highest major river in the world, flowing from west to east across Tibet, China and pouring into India. Macroinvertebrates were sampled from Yalutsangpo and its tributaries, the Lhasa, Niyang, and Parlong Tsangpo Rivers, from October 2009 to June 2010, to study characters of the highland aquatic ecosystem. Altogether, 110 macroinvertebrate taxa belonging to 57 families and 102 genera were identified from the basin. The biodiversity and composition of macroinvertebrate assemblages were strongly affected by altitude gradients. Local diversity represented by taxa richness and the improved Shannon-Wiener index were high at altitudes of 3,300-3,700 m, among which suitability of habitat was higher due to the better integrated environmental conditions of water temperature, dissolved oxygen, and aquatic vegetation, etc. Macroinvertebrates were grouped into shredders, scrapers, predators, collector-filterers, and collector-gatherers according to their feeding behaviors. It was found that the distributions of the functional feeding groups varied with habitat altitudes. Shredders were present at altitudes of 2,900-4,400 m, while scrapers mainly inhabited altitudes of 3,500-4,500 m, and collector-filterers preferred 3,500-4,000 m. Even though the local taxa richness was not high at each site, the taxonomic composition and density of the assemblages varied greatly among the different sites, resulting in much higher regional diversity compared to the lowland river with similar flow and substrate conditions. The regional cumulative taxa richness of Yalutsangpo decreased and more families were lost as the altitude increased. However, some families that were newly present as the altitude increased were essential for sustaining the high

  17. [Functional feeding groups of macroinvertebrates in Gaira river, Colombia].

    PubMed

    Rodríguez-Barrios, Javier; Ospina-Tórres, Rodulfo; Turizo-Correa, Rodrigo

    2011-12-01

    Tropical rivers are frequently described on their biodiversity but few studies have considered the ecological value of this richness in their food webs. We determined the trophic structure of aquatic macroinvertebrate communities (expressed in the richness and abundance of taxa and biomass proportions of different functional feeding groups) at the level of the river, stretch and microhabitats (functional units - UFs). We evaluated the spatial and temporal variation of these descriptors during wet and dry events, and selected three sites associated with different altitudinal belts. We reported 109 taxa, with 11167 individuals who contributed 107.11g of biomass. Density of macroinvertebrates was favored with increasing height, and biomass showed the opposite pattern (K-W = 10.1, d.f. = 1, p < 0.05), due to the addition of large crustaceans (Macrobrachium), and the taxa diversity was higher in the middle stretch of the river (H'=3.16). The Gaira stream runs through a mid-sized river basin, for this reason we found mainly bedrock (epilithon = 50.5%), gravel and sand (43.7%). The functional unit with more habitat and food resources that contains a higher abundance of leaf litter macroinvertebrates was foliage followed by epilithon, fine sediment and gravel-sand (K-W = 25.3, d.f. = 3, p < 0.05). The biomass values of these organisms were higher in leaves followed by gravel-sands, epilithon and sediment (K-W = 15.3, d.f. = 3, p < 0.05). Autochthonous biomass input by different functional feeding groups can be considered very low, but they define the functionality of the stream, being represented almost exclusively by shredders (Macrobrachium, 73%), present only in the lower reaches, followed by shredder Leptonema with 15%, located mostly in the upper reaches and predatory stoneflies of the genus Anacroneuria to 6.56%, which dominated in the middle stretch of stream. Excluding Macrobrachium from the analysis, there was dominance of Anacroneuria in the lower reaches

  18. Tracking an Escherichia coli O157:H7-contaminated batch of leafy greens through a pilot-scale fresh-cut processing line.

    PubMed

    Buchholz, Annemarie L; Davidson, Gordon R; Marks, Bradley P; Todd, Ewen C D; Ryser, Elliot T

    2014-09-01

    Cross-contamination of fresh-cut leafy greens with residual Escherichia coli O157:H7-contaminated product during commercial processing was likely a contributing factor in several recent multistate outbreaks. Consequently, radicchio was used as a visual marker to track the spread of the contaminated product to iceberg lettuce in a pilot-scale processing line that included a commercial shredder, step conveyor, flume tank, shaker table, and centrifugal dryer. Uninoculated iceberg lettuce (45 kg) was processed, followed by 9.1 kg of radicchio (dip inoculated to contain a four-strain, green fluorescent protein-labeled nontoxigenic E. coli O157:H7 cocktail at 10(6) CFU/g) and 907 kg (2,000 lb) of uninoculated iceberg lettuce. After collecting the lettuce and radicchio in about 40 bags (∼22.7 kg per bag) along with water and equipment surface samples, all visible shreds of radicchio were retrieved from the bags of shredded product, the equipment, and the floor. E. coli O157:H7 populations were quantified in the lettuce, water, and equipment samples by direct plating with or without prior membrane filtration on Trypticase soy agar containing 0.6% yeast extract and 100 ppm of ampicillin. Based on triplicate experiments, the weight of radicchio in the shredded lettuce averaged 614.9 g (93.6%), 6.9 g (1.3%), 5.0 g (0.8%), and 2.8 g (0.5%) for bags 1 to 10, 11 to 20, 21 to 30, and 31 to 40, respectively, with mean E. coli O157:H7 populations of 1.7, 1.2, 1.1, and 1.1 log CFU/g in radicchio-free lettuce. After processing, more radicchio remained on the conveyor (9.8 g; P < 0.05), compared with the shredder (8.3 g), flume tank (3.5 g), and shaker table (0.1 g), with similar E. coli O157:H7 populations (P > 0.05) recovered from all equipment surfaces after processing. These findings clearly demonstrate both the potential for the continuous spread of contaminated lettuce to multiple batches of product during processing and the need for improved equipment designs that minimize

  19. A hairy case: The evolution of filtering carnivorous Drusinae (Limnephilidae, Trichoptera).

    PubMed

    Vitecek, Simon; Graf, Wolfram; Previšić, Ana; Kučinić, Mladen; Oláh, János; Bálint, Miklós; Keresztes, Lujza; Pauls, Steffen U; Waringer, Johann

    2015-12-01

    The caddisfly subfamily Drusinae BANKS comprises roughly 100 species inhabiting mountain ranges in Europe, Asia Minor and the Caucasus. A 3-gene phylogeny of the subfamily previously identified three major clades that were corroborated by larval morphology and feeding ecologies: scraping grazers, omnivorous shredders and filtering carnivores. Larvae of filtering carnivores exhibit unique head capsule complexities, unknown from other caddisfly larvae. Here we assess the species-level relationships within filtering carnivores, hypothesizing that head capsule complexity is derived from simple shapes observed in the other feeding groups. We summarize the current systematics and taxonomy of the group, clarify the systematic position of Cryptothrix nebulicola, and present a larval key to filtering carnivorous Drusinae. We infer relationships of all known filtering carnivorous Drusinae and 34 additional Drusinae species using Bayesian species tree analysis and concatenated Bayesian phylogenetic analysis of 3805bp of sequence data from six gene regions (mtCOI5-P, mtCOI3-P, 16S mrDNA, CADH, WG, 28S nrDNA), morphological cladistics from 308 characters, and a total evidence analysis. All analyses support monophyly of the three feeding ecology groups but fail to fully resolve internal relationships. Within filtering carnivores, variation in head setation and frontoclypeus structure may be associated with progressive niche adaptation, with less complex species recovered at a basal position. We propose that diversification of complex setation and frontoclypeus shape represents a recent evolutionary development, hypothetically enforcing speciation and niche specificity within filtering carnivorous Drusinae. PMID:26265260

  20. Used tire recycling to produce granulates: evaluation of occupational exposure to chemical agents.

    PubMed

    Savary, Barbara; Vincent, Raymond

    2011-10-01

    Exposure was assessed in four facilities where used tires are turned into rubber granulates. Particulate exposure levels were measured using filter samples and gravimetric analysis. In parallel, volatile organic compounds (VOCs) screening was carried out using samples taken on activated carbon supports, followed by an analysis using a gas chromatograph coupled to a spectrometric detector. The exposure level medians are between 0.58 and 3.95 mg m(-3). Clogging of the textile fiber separation systems can lead to worker exposure; in this case, the measured concentrations can reach 41 mg m(-3). However, in contrast to the data in the literature, VOC levels >1 p.p.m. were not detected. The particulate mixtures deposited on the installation surfaces are complex; some of the chemical agents are toxic to humans. The results of this study indicate significant exposure to complex mixtures of rubber dust. Optimizing exhaust ventilation systems inside the shredders, with a cyclone for example, is essential for reducing the exposure of workers in this rapidly developing sector.

  1. Gammarus spp. in aquatic ecotoxicology and water quality assessment: toward integrated multilevel tests.

    PubMed

    Kunz, Petra Y; Kienle, Cornelia; Gerhardt, Almut

    2010-01-01

    The amphipod genus Gammarus is widespread and is structurally and functionally important in epigean freshwaters of the Northern Hemisphere. Its presence is crucial, because macroinvertebrate feeding is a major rate-limiting step in the processing of stream detrius. In addition, Gammarus interacts with multiple trophic levels bu functioning as prey, predator, herbivore, detritivore, and shredder. Such a broad span of ecosystem participation underlines the importance of Gammarus to pollutants and other disturbances may render it a valuable indicator for ecosystem health. This review summarizes the vast number of studies conducted with Gammarus spp. for evaluating aquatic ecotoxicology endpoints and examines the suitability of this native invertabrate species for the assessment of stream ecosystem health in the Northern Hemisphere. Numerous papers have been published on how pollutants affect gammarind behavior (i.e., mating, predator avoidance), reproduction, development, feeding activity, population structure, as well as the consequences of pollution on host-parasite, predator-prey, or native-invasive species interactions. Some biochemical and molecular biomarkers have already been established, such as the measurement of vitellogenin-like proteins, metallothioneins, alkali-labile phosphates (in proteins), and lipogenic enzyme activities for assessing endocrine distribution and detoxification mechanisms.

  2. The Nature of Diamonds

    NASA Astrophysics Data System (ADS)

    Harlow, George E.

    1997-10-01

    The paragon of physical perfection and a sparkling example of Earth's forces at work, the diamond has fascinated all realms of society, from starlets to scientists. The Nature of Diamonds is a comprehensive look at nature's most coveted gem. A handsome, large-format book, The Nature of Diamonds is an authoritative and richly-illustrated tribute to the diamond. Leading geologists, gemologists, physicists, and cultural observers cover every facet of the stone, from its formation in the depths of the Earth, its ascent to the surface, and its economic, regal, social, and technological roles. Cutting-edge research takes the reader to the frontiers of diamond exploration and exploitation, from the Arctic wastes to the laboratories where diamonds are created for massive road shredders that rip up and then re-create superhighways. Here also is an overview of cutting, from the rough stones in Roman rings to the highly-faceted stones we see today, and a glimpse into the business of diamonds. Finally, The Nature of Diamonds chronicles scientific and cultural history and explores the diamond as both a sacred and a social symbol, including a picture history of betrothal rings. Wide-ranging illustrations explain the geology of diamonds, chart the history of mining from its origins in India and Brazil through the diamond rush in South Africa and today's high-tech enterprises, and capture the brilliance and beauty of this extraordinary gem. _

  3. A Stream Multimetric Macroinvertebrate Index (MMI) for the Sand Hills Ecoregion of the Southeastern Plains, USA.

    PubMed

    Kosnicki, Ely; Sefick, Stephen A; Paller, Michael H; Jerrell, Miller S; Prusha, Blair A; Sterrett, Sean C; Tuberville, Tracey D; Feminella, Jack W

    2016-10-01

    A macroinvertebrate multimetric index is an effective tool for assessing the biological integrity of streams. However, data collected under a single protocol may not be available for an entire region. We sampled macroinvertebrates from the full extent of the Sand Hills ecoregion Level IV of the Southeastern Plains with a standard protocol during the summers of 2010-2012. We evaluated the performance of 94 metrics through a series of screening criteria and built 48 macroinvertebrate multimetric indexs with combinations of the best performing metrics, representing richness, habit, functional feeding guild, sensitivity, and community composition. A series of narrative-response tests for each macroinvertebrate multimetric index was used to find the best performing macroinvertebrate multimetric index which we called the Sand Hills macroinvertebrate multimetric index. The Sand Hills macroinvertebrate multimetric index consisted of the measures Biotic Index, % Shredder taxa, Clinger taxa(2)/total taxa, Plecoptera and Trichoptera richness, and Tanytarsini taxa(2)/Chironomidae taxa. Comparison of the Sand Hills macroinvertebrate multimetric index with existing assessment tools calculated with our data indicated that the Sand Hills macroinvertebrate multimetric index performs at a high level with regard to identifying degraded sites and in its response to stress gradients. PMID:27581726

  4. Executive summary of the Cryofracture demonstration program

    SciTech Connect

    Loomis, G.; Osborne, D.; Ancho, M.

    1991-09-01

    This report provides an executive summary of the Cryofracture demonstration program performed at Nuclear Remedial Technologies Corporation under contract to EG G Idaho, Inc., for the Department of Energy (DOE). Cryofracture is a size-reducing process whereby objects are frozen whereby objects are frozen to liquid nitrogen temperatures and crushed in a large hydraulic press. Material at the cryogenic temperatures have low ductility and are easily size reduced by fracturing. The main application being investigated for the DOE is for retrieved buried and stored transuranic (TRU) waste. Six 55-gallon drums and six 2 ft {times} 2 ft {times} 8 ft boxes containing simulated waste with tracers were subjected to the Cryofracture process. Data was obtained on (a) cool-down time, (b) yield strength of the containers, (c) size distribution of the waste before and after the Cryofracture process, (d) volume reduction of the waste, and (e) sampling of air and surface dusts for spread of tracers to evaluate potential contamination spread. The Cryofracture process was compared to conventional shredders and detailed cost estimates were established for construction of a Cryofracture facility at the Idaho National Engineering Laboratory. Although cost estimates for conventional shredding are higher for Cryofracture, the potential for fire and explosion during conventional shredding would incur additional costs to preclude these events. These additional costs are unknown and would require considerable research and development. 4 refs., 6 figs., 7 tabs.

  5. Ecosystem monitoring at global baseline sites.

    PubMed

    Bruns, D A; Wiersma, G B; Rykiel, E J

    1991-04-01

    Integrated ecosystem and pollutant monitoring is being conducted at prototype global baseline sites in remote areas of the Noatak National Preserve, Alaska, the Wind River Mountains, Wyoming, and Torres del Paine National Park, Chile. A systems approach has been used in the design of these projects. This approach includes: (1) evaluation of source-receptor relationships, (2) multimedia (i.e., air, water, soil, biota) monitoring of key contaminant pathways within the environment, (3) the use of selected ecosystem parameters to detect anthropogenic influence, and (4) the application of a systems conceptual framework as a heuristic tool.Initial short-term studies of air quality (e.g. SO2, NO2) plus trace metal concentrations in mosses generally indicate pristine conditions at all three of the above sites as expected although trace metals in mosses were higher at the Wyoming site. Selected ecosystem parameters for both terrestrial (e.g. litter decomposition) and aquatic (e.g. shredders, a macroinvertebrate functional feeding group) habitats at the Wyoming site reflected baseline conditions when compared to other studies.Plans also are being made to use U.S. Department of Energy Research Parks for global change monitoring. This will involve cross-site analyses of existing ecological databases and the design of a future monitoring network based on a systems approach as outlined in this paper.

  6. [Relationships of Syzygium jambos and Dracontomelon duperreanum leaf tannin concentration and leaf litter breakdown with the colonization of benthonic invertebrates].

    PubMed

    Guan, Zhao-Ying; Zhao, Ying; Tong, Xiao-Li

    2009-10-01

    An investigation was made on the dynamic changes of tannin concentration in Syzygium jambos and Dracontomelon duperreanum leaves over a 105-day period of leaf litter decomposition in a second-order stream in Longdong Reservoir, Guangzhou. The initial tannin concentration in S. jambos leaves (0.191 g x g(-1) DM) was higher than that in D. duperreanum leaves (0.057 g x g(-1) DM). In the first week of leaf litter decomposition, the tannin concentration in D. duperreanum and S. jambos leaves decreased by 45% and 22% respectively. 21 days after, the decline in tannin concentration slowed down, but the decomposition rate increased, with the leaves of D. duperreanum decomposed faster than those of S. jambos (k value was 0.038 d(-1) and 0.013 d(-1), respectively). The average density of benthonic invertebrate colonized on D. duperreanum leaves (287.9 ind x g(-1) leaf mass) was significantly higher than that on S. jambos leaves (26.2 ind x g(-1) leaf mass) (P < 0.05). A continual increase of benthonic invertebrate's abundance was observed during leaf litter decomposition, which could be attributed to the rapid decrease of leaf tannin concentration. The slower breakdown of S. jambos leaf litter was likely because of the high tannin concentration in S. jambos leaves, which inhibited benthonic invertebrate, especially the shredder's colonization.

  7. Life-cycle assessment of selected management options for air pollution control residues from waste incineration.

    PubMed

    Fruergaard, Thilde; Hyks, Jiri; Astrup, Thomas

    2010-09-15

    Based on available technology and emission data seven selected management options for air-pollution-control (APC) residues from waste incineration were evaluated by life-cycle assessment (LCA) using the EASEWASTE model. Scenarios were evaluated with respect to both non-toxicity impact categories (e.g. global warming) and toxicity related impact categories (e.g. ecotoxicity and human toxicity). The assessment addressed treatment and final placement of 1 tonne of APC residue in seven scenarios: 1) direct landfilling without treatment (baseline), 2) backfilling in salt mines, 3) neutralization of waste acid, 4) filler material in asphalt, 5) Ferrox stabilization, 6) vitrification, and 7) melting with automobile shredder residues (ASR). The management scenarios were selected as examples of the wide range of different technologies available worldwide while at the same time using realistic technology data. Results from the LCA were discussed with respect to importance of: energy consumption/substitution, material substitution, leaching, air emissions, time horizon aspects for the assessment, and transportation distances. The LCA modeling showed that thermal processes were associated with the highest loads in the non-toxicity categories (energy consumption), while differences between the remaining alternatives were small and generally considered insignificant. In the toxicity categories, all treatment/utilization options were significantly better than direct landfilling without treatment (lower leaching), although the thermal processes had somewhat higher impacts than the others options (air emissions). Transportation distances did not affect the overall ranking of the management alternatives.

  8. Characterisation of polycyclic aromatic hydrocarbons in flue gas and residues of a full scale fluidized bed combustor combusting non-hazardous industrial waste.

    PubMed

    Van Caneghem, J; Vandecasteele, C

    2014-11-01

    This paper studies the fate of PAHs in full scale incinerators by analysing the concentration of the 16 EPA-PAHs in both the input waste and all the outputs of a full scale Fluidized Bed Combustor (FBC). Of the analysed waste inputs i.e. Waste Water Treatment (WWT) sludge, Refuse Derived Fuel (RDF) and Automotive Shredder Residue (ASR), RDF and ASR were the main PAH sources, with phenanthrene, fluoranthene and pyrene being the most important PAHs. In the flue gas sampled at the stack, naphthalene was the only predominant PAH, indicating that the PAHs in FBC's combustion gas were newly formed and did not remain from the input waste. Of the other outputs, the boiler and fly ash contained no detectable levels of PAHs, whereas the flue gas cleaning residue contained only low concentrations of naphthalene, probably adsorbed from the flue gas. The PAH fingerprint of the bottom ash corresponded rather well to the PAH fingerprint of the RDF and ASR, indicating that the PAHs in this output, in contrast to the other outputs, were mainly remainders from the PAHs in the waste inputs. A PAH mass balance showed that the total PAH input/output ratio of the FBC ranged from about 100 to about 2600 depending on the waste input composition and the obtained combustion conditions. In all cases, the FBC was clearly a net PAH sink. PMID:25002370

  9. Physical analyses of compost from composting plants in Brazil.

    PubMed

    Barreira, L P; Philippi Junior, A; Rodrigues, M S; Tenório, J A S

    2008-01-01

    Nowadays the composting process has shown itself to be an alternative in the treatment of municipal solid wastes by composting plants. However, although more than 50% of the waste generated by the Brazilian population is composed of matter susceptible to organic composting, this process is, still today, insufficiently developed in Brazil, due to low compost quality and lack of investments in the sector. The objective of this work was to use physical analyses to evaluate the quality of the compost produced at 14 operative composting plants in the Sao Paulo State in Brazil. For this purpose, size distribution and total inert content tests were done. The results were analyzed by grouping the plants according to their productive processes: plants with a rotating drum, plants with shredders or mills, and plants without treatment after the sorting conveyor belt. Compost quality was analyzed considering the limits imposed by the Brazilian Legislation and the European standards for inert contents. The size distribution tests showed the influence of the machinery after the sorting conveyer on the granule sizes as well as the inert content, which contributes to the presence of materials that reduce the quality of the final product. PMID:17855069

  10. ARCIMBOLDO_LITE: single-workstation implementation and use.

    PubMed

    Sammito, Massimo; Millán, Claudia; Frieske, Dawid; Rodríguez-Freire, Eloy; Borges, Rafael J; Usón, Isabel

    2015-09-01

    ARCIMBOLDO solves the phase problem at resolutions of around 2 Å or better through massive combination of small fragments and density modification. For complex structures, this imposes a need for a powerful grid where calculations can be distributed, but for structures with up to 200 amino acids in the asymmetric unit a single workstation may suffice. The use and performance of the single-workstation implementation, ARCIMBOLDO_LITE, on a pool of test structures with 40-120 amino acids and resolutions between 0.54 and 2.2 Å is described. Inbuilt polyalanine helices and iron cofactors are used as search fragments. ARCIMBOLDO_BORGES can also run on a single workstation to solve structures in this test set using precomputed libraries of local folds. The results of this study have been incorporated into an automated, resolution- and hardware-dependent parameterization. ARCIMBOLDO has been thoroughly rewritten and three binaries are now available: ARCIMBOLDO_LITE, ARCIMBOLDO_SHREDDER and ARCIMBOLDO_BORGES. The programs and libraries can be downloaded from http://chango.ibmb.csic.es/ARCIMBOLDO_LITE. PMID:26327382

  11. Performance Analysis of Weld Hardfacings Used in the Sugar/Alcohol Industry

    NASA Astrophysics Data System (ADS)

    Lima, Aldemi Coelho; Ferraresi, Valtair Antonio; Reis, Ruham Pablo

    2014-05-01

    The increasing demand for biofuel has pushed the sugar/alcohol industry to expansion, especially in Brazil. In this industry, the costs linked to equipment wear are significant. Abrasive wear is particularly present, especially in shredder knives, which are produced/repaired by weld hardfacings. In this case, FCAW has become a common choice. Considering the lack of results based on real-work wear conditions in such sector, this study compares the performance of weld hardfacings in laboratory and in industry. Three types of FCAW wires (FeCrC alloys) are assessed and compared to a SMAW electrode. The performance of the hardfacings is determined in terms of wear resistance and related to the microstructures produced. The laboratory test did not replicate the industry conditions. The FeCrC + Nb hardfacings had the best performance in laboratory (similar to the SMAW deposits), but the worst in industry. The FeCrC and FeCrC + Ti hardfacings, respectively, were the worst in laboratory and the best in industry (similar to the SMAW deposits). Spalling was decisive for poor hardfacing performance. The absence of cracks in the FeCrC + Ti hardfacings was crucial for their superior industry performance. A test combining abrasion and impact would better represent the wear really acting on the parts.

  12. New developments in the processing of the non ferrous metal fraction of car scrap

    SciTech Connect

    Dalmijn, W.L.; Houwelingen, J.A. van

    1995-12-31

    The processing of scrap and scrap cars starts with size reduction by a hammermill, or shredder. After the liberation the magnetic fraction is removed. The remaining nonmagnetic fraction mixed with other materials is screened and each fraction is processed separately. The increased use of plastic has a negative effect on the recovery of metals and waste production. At Huron Valley, Belleville Michigan, USA, the non-ferrous fraction from 5 million obsolete cars per year, containing 200,000 tons of non-ferrous metal, is processed. Aluminium is recovered with a heavy medium separation process and concentrated with eddy current separators. The remaining heavy non-ferrous fraction is concentrated by a new combination of eddy current separation and image processing. After this separation process the zinc fraction is melted and refined and the copper, brass, stainless steel and other high-quality concentrates are sold to the secondary industries. The recycling of car scrap has become an important source of metals and materials for the secondary materials processing industry.

  13. The relative importance of diet-related and waterborne effects of copper for a leaf-shredding invertebrate.

    PubMed

    Zubrod, J P; Englert, D; Rosenfeldt, R R; Wolfram, J; Lüderwald, S; Wallace, D; Schnetzer, N; Schulz, R; Bundschuh, M

    2015-10-01

    Copper (Cu) exposure can increase leaf-associated fungal biomass, an important food component for leaf-shredding macroinvertebrates. To test if this positive nutritional effect supports the physiological fitness of these animals and to assess its importance compared to waterborne toxicity, we performed a 24-day-bioassay in combination with a 2×2 factorial design using the amphipod shredder Gammarus fossarum and a field-relevant Cu concentration of 25 μg/L (n = 65). Waterborne toxicity was negligible, while gammarids fed leaves exposed to Cu during microbial colonization exhibited a near-significant impairment in growth (∼30%) and a significantly reduced lipid content (∼20%). These effects appear to be governed by dietary uptake of Cu, which accumulated in leaves as well as gammarids and likely overrode the positive nutritional effect of the increased fungal biomass. Our results suggest that for adsorptive freshwater contaminants dietary uptake should be evaluated already during the registration process to safeguard the integrity of detritus-based ecosystems.

  14. Ecotoxicity and fungal deterioration of recycled polypropylene/wood composites: effect of wood content and coupling.

    PubMed

    Sudár, András; López, María J; Keledi, Gergely; Vargas-García, M Carmen; Suárez-Estrella, Francisca; Moreno, Joaquín; Burgstaller, Christoph; Pukánszky, Béla

    2013-09-01

    Recycled polypropylene (rPP) was recovered from an industrial shredder and composites were prepared with a relatively wide range of wood content and with two coupling agents, a maleated PP (MAPP) and a maleated ethylene-propylene-diene elastomer (MAEPDM). The mechanical properties of the composites showed that the coupling agents change structure only slightly, but interfacial adhesion quite drastically. The durability of the materials was determined by exposing them to a range of fungi and, ecotoxicity was studied on the aquatic organism Vibrio fischeri. The composites generally exhibit low acute toxicity, with values below the levels considered to have direct ecotoxic effect on aquatic ecosystems (<2 toxic units). Their toxicity to V. fischeri depended on the presence of the coupling agents with larger E50 values in 24-h aqueous extracts from composites containing MAPP or MAEPDM in comparison to composites without any coupling agent. Evaluation of resistance against fungal colonization and deterioration proved that wood facilitates fungal colonization. Fungi caused slight mass loss (below 3%) but it was not correlated with substantial deterioration in material properties. MAPP seems to be beneficial in the retention of mechanical properties during fungal attack. rPP/wood composites can be considered non-ecotoxic and quite durable, but the influence of wood content on resistance to fungal attack must be taken into account for materials intended for applications requiring long-term outdoor exposure. PMID:23769467

  15. Jointly sponsored research program. Quarterly technical progress report, October--December 1993

    SciTech Connect

    Deans, H.A.

    1994-05-01

    This is a progress report on work performed by Western Research Institute for the U.S. DOE, Morgantown Energy Technology Center in the period October- December 1993. Tasks addressed include: development and demonstration of a practical electric downhole steam generator for thermal recovery of heavy oil and tar; wetting behavior of selected crude oil/brine/rock systems; coal gasification, power generation, and product market study; the impact of leachate from clean coal technology waste on the stability of clay liners; investigation of coprocessing of heavy oil, automobile shredder residue, and coal; injection into coal seams for simultaneous CO{sub 2} mitigation and enhanced recovery of coalbed methane; optimization of carbonizer operations in the FMC coke process; chemical sensor and field screening technology development; demonstration of the koppelman {open_quotes}series c{close_quotes} process using a batch test unit with Powder River Basin coal as feed; remote chemical sensor development; market assessment and technical feasibility study of PFBC ash use; solid-state NMR analysis and interpretation of naturally and artificially matured kerogens; Crow{trademark} field demonstration with bell lumber and pole; {open_quotes}B{close_quotes} series pilot plant tests; in situ treatment of manufactured gas plant contaminated soils demonstration program.

  16. ARCIMBOLDO_LITE: single-workstation implementation and use.

    PubMed

    Sammito, Massimo; Millán, Claudia; Frieske, Dawid; Rodríguez-Freire, Eloy; Borges, Rafael J; Usón, Isabel

    2015-09-01

    ARCIMBOLDO solves the phase problem at resolutions of around 2 Å or better through massive combination of small fragments and density modification. For complex structures, this imposes a need for a powerful grid where calculations can be distributed, but for structures with up to 200 amino acids in the asymmetric unit a single workstation may suffice. The use and performance of the single-workstation implementation, ARCIMBOLDO_LITE, on a pool of test structures with 40-120 amino acids and resolutions between 0.54 and 2.2 Å is described. Inbuilt polyalanine helices and iron cofactors are used as search fragments. ARCIMBOLDO_BORGES can also run on a single workstation to solve structures in this test set using precomputed libraries of local folds. The results of this study have been incorporated into an automated, resolution- and hardware-dependent parameterization. ARCIMBOLDO has been thoroughly rewritten and three binaries are now available: ARCIMBOLDO_LITE, ARCIMBOLDO_SHREDDER and ARCIMBOLDO_BORGES. The programs and libraries can be downloaded from http://chango.ibmb.csic.es/ARCIMBOLDO_LITE.

  17. Cost and Productivity of Multi-Product Processing for Small Diameter Trees : Final Report.

    SciTech Connect

    Lambert, Michael B.; Howard, James O.; Hermann, Steven E.

    1987-09-01

    This project evolved from an effort by the land manager, the United States Forest Service, to economically deal with thousands of acres of thick (doghair) Douglas-fir and hemlock forests on Washington's Olympic Peninsula. These forests are very densely stocked and the trees are small. Until this effort, there has been no reasonable way to get enough product from the sites to justify managing them. And, even this project required some special agreements between the landowner and the investigator to be viable. This report describes the in-woods processing system now working in doghair stands on the Quilcene District. As whole trees arrive at the landing, they are sorted by a Cat 225 shovel-type loader. Sawlogs are trimmed, limbed, bucked, and decked for transportation on conventional log trucks. Chip grade trees are passed through a prototype, multi-stem debarker/delimber and then chipped by a Morbark 23'' Chiparvester. Clean chips are transported in regular highway chip vans. All other materials, not sold as logs or clean chips, are processed by a prototype shredder, and taken from the site as hogfuel. 7 ref., 15 figs., 11 tabs.

  18. Biomass of macroinvertebrates and physicochemical characteristics of water in an Andean urban wetland of Colombia.

    PubMed

    Rivera-Usme, J J; Pinilla, G A; Rangel-Churio, J O; Castro, M I; Camacho-Pinzón, D L

    2015-01-01

    Aquatic macroinvertebrates (AMI) play an important role in the ecology of wetlands, either by their job as regulators of the cycles of matter, as for their energy storage function represented in their biomass, which is transferred to higher trophic levels. To answer the question of how biomass of different AMI trophic guilds is related with physicochemical variables in the wetland Jaboque (Bogotá, Colombia), four samplings were achieved between April 2009 and January 2010, according to periods of rain and drought in the region. The AMI biomass values obtained were rated as of intermediate rank. No temporal but spatial significant differences were found. Apparently these spatial differences appear to be associated with variations in anthropogenic pressure, which differs in each area of the wetland. In dry months (January and August), biomass was greater and dominated by detritivores. We observed a positive relationship between the specific conductance of water and the biomass of predators and detritivores and between water temperature and the biomass of detritivores and shredders. These relationships suggest that the physical and chemical variables influence the distribution, abundance, and biomass of functional groups. The physical and chemical conditions of water exhibited spatiotemporal fluctuations related to changes in the concentration of organic matter and nutrients, which presumably were related to the affluents discharges and the high impact of local human populations.

  19. Responses of freshwater plants and invertebrates to acidification

    SciTech Connect

    Hendrey, G.R.; Yan, N.D.; Baumgartner, K.J.

    1980-01-01

    Acidic, oligotrophic, clear waters often have strong similarities among their biota. In the phytoplankton, Dinophyceae, and to a lesser extent Chrysophyceae tend to dominate. Production of 25 Canadian Shield lakes (pH 6.1-7.1) ranged from 25 to 240 mg C m/sup -2/ d/sup -1/. Both biomass and production appear to be controlled by the supply and bio-availability of phosphorus rather than pH per se. We found little evidence of possible C limitation in acidified lakes. There does not appear to be a direct relationship between (H/sup +/) and biomass density in lakes, as illustrated by whole-lake manipulations of (H/sup +/) and total phosphorus (TP). These studies, however, do not examine effects of acidification on the whole lake-watershed system. It is suggested that watershed acidification processes such as leaching of Al may reduce TP loading to lakes. Zooplankton community biomass appears to be reduced at low pH and small-bodied forms may dominate. Among the zoobenthos, biomass does appear to be reduced in some lakes but not others. Various studies found shredders; collectors and scrapers to be reduced more than raptorial species. We hypothesize that removal of fish predation on benthos allows a relative increase in the invertebrate predators, reduction of herbivores (chironomids are relatively abundant) and the subsequent increase in benthic algae observed in many waters.

  20. Anaerobic co-digestion of sewage sludge with shredded grass from public green spaces.

    PubMed

    Hidaka, Taira; Arai, Sayuri; Okamoto, Seiichiro; Uchida, Tsutomu

    2013-02-01

    Adding greenery from public spaces to the co-digestion process with sewage sludge was evaluated by shredding experiments and laboratory-scale batch and continuous mesophilic anaerobic fermentation experiments. The ratio of the shredded grass with 20mm or less in length by a commercially available shredder was 93%. The methane production was around 0.2NL/gVS-grass in the batch experiment. The continuous experiment fed with sewage sludge and shredded grass was stably operated for 81days. The average methane production was 0.09NL/gVS-grass when the TS ratio of the sewage sludge and the grass was 10:1. This value was smaller than those of other reports using grass silage, but the grass species in this study were not managed, and the collected grass was just shredded and not ensiled before feeding to the reactor for simple operation. The addition of grass to a digester can improve the carbon/nitrogen ratio, methane production and dewaterability.

  1. Vegetative Regeneration Capacities of Five Ornamental Plant Invaders After Shredding

    NASA Astrophysics Data System (ADS)

    Monty, Arnaud; Eugène, Marie; Mahy, Grégory

    2015-02-01

    Vegetation management often involves shredding to dispose of cut plant material or to destroy the vegetation itself. In the case of invasive plants, this can represent an environmental risk if the shredded material exhibits vegetative regeneration capacities. We tested the effect of shredding on aboveground and below-ground vegetative material of five ornamental widespread invaders in Western Europe that are likely to be managed by cutting and shredding techniques: Buddleja davidii (butterfly bush, Scrophulariaceae), Fallopia japonica (Japanese knotweed, Polygonaceae), Spiraea × billardii Hérincq (Billard's bridewort, Rosaceae), Solidago gigantea (giant goldenrod, Asteraceae), and Rhus typhina L. (staghorn sumac, Anacardiaceae). We looked at signs of vegetative regeneration and biomass production, and analyzed the data with respect to the season of plant cutting (spring vs summer), the type of plant material (aboveground vs below-ground), and the shredding treatment (shredded vs control). All species were capable of vegetative regeneration, especially the below-ground material. We found differences among species, but the regeneration potential was generally still present after shredding despite a reduction of growth rates. Although it should not be excluded in all cases (e.g., destruction of giant goldenrod and staghorn sumac aboveground material), the use of a shredder to destroy woody alien plant material cannot be considered as a general management option without significant environmental risk.

  2. Comparison of steam sterilization conditions efficiency in the treatment of Infectious Health Care Waste.

    PubMed

    Maamari, Olivia; Mouaffak, Lara; Kamel, Ramza; Brandam, Cedric; Lteif, Roger; Salameh, Dominique

    2016-03-01

    Many studies show that the treatment of Infectious Health Care Waste (IHCW) in steam sterilization devices at usual operating standards does not allow for proper treatment of Infectious Health Care Waste (IHCW). Including a grinding component before sterilization allows better waste sterilization, but any hard metal object in the waste can damage the shredder. The first objective of the study is to verify that efficient IHCW treatment can occur at standard operating parameters defined by the contact time-temperature couple in steam treatment systems without a pre-mixing/fragmenting or pre-shredding step. The second objective is to establish scientifically whether the standard operation conditions for a steam treatment system including a step of pre-mixing/fragmenting were sufficient to destroy the bacterial spores in IHCW known to be the most difficult to treat. Results show that for efficient sterilization of dialysis cartridges in a pilot 60L steam treatment system, the process would require more than 20 min at 144°C without a pre-mixing/fragmenting step. In a 720L steam treatment system including pre-mixing/fragmenting paddles, only 10 min at 144°C are required to sterilize IHCW proved to be sterilization challenges such as dialysis cartridges and diapers in normal conditions of rolling.

  3. Circulating fluidized-bed boiler makes inroads for waste recycling

    SciTech Connect

    1995-09-01

    Circulating fluidized-bed (CFB) boilers have ben used for years in Scandinavia to burn refuse-derived fuel (RDF). Now, Foster Wheeler Power Systems, Inc., (Clinton, N.J.) is bringing the technology to the US. Touted as the world`s largest waste-to-energy plant to use CFB technology, the Robbins (III.) Resource Recovery Facility will have the capacity to process 1,600 tons/d of municipal solid waste (MSW) when it begins operation in early 1997. The facility will have two materials-separation and RDF-processing trains, each with dual trommel screens, magnetic and eddy current separators, and shredders. About 25% of the incoming MSW will be sorted and removed for recycling, while 75% of it will be turned into fuel, with a heat value of roughly 6,170 btu/lb. Once burned in the twin CFB boilers the resulting steam will be routed through a single turbine generator to produce 50,000 mW of electric power.

  4. Variable role of aquatic macroinvertebrates in initial breakdown of seasonal leaf litter inputs to a cold-desert river

    USGS Publications Warehouse

    Nelson, S.M.; Andersen, D.C.

    2007-01-01

    We used coarse-mesh and fine-mesh leafpacks to examine the importance of aquatic macroinvertebrates in the breakdown of floodplain tree leaf litter that seasonally entered a sand-bedded reach of the sixth-order Yampa River in semiarid Colorado. Leafpacks were positioned off the easily mobilized channel bed, mimicking litter trapped in debris piles. Organic matter (OM) loss was fastest for leaves collected from the floodplain and placed in the river in spring (k = 0.029/day) and slowest for leaves collected and placed in the river in winter (0.006/day). Macroinvertebrates were most abundant in winter and spring leaves, but seemed important to processing only in spring, when exclusion by fine mesh reduced OM loss by 25% and nitrogen loss by 65% in spring leaves. Macroinvertebrates seemed to have little role in processing of autumn, winter, or summer leaves over the 50-day to 104-day monitoring periods. Desiccation during bouts of low discharge and sediment deposition on leaves limited invertebrate processing in summer and autumn, whereas processing of winter leaves, which supported relatively large numbers of shredders, might have been restricted by ice formation and low water temperatures. These results were consistent with the concept that microbial processing dominates in higher-order rivers, but suggested that macroinvertebrate processing can be locally important in higher-order desert rivers in seasons or years with favorable discharge and water quality conditions.

  5. Environmental impact of incineration of calorific industrial waste: rotary kiln vs. cement kiln.

    PubMed

    Vermeulen, Isabel; Van Caneghem, Jo; Block, Chantal; Dewulf, Wim; Vandecasteele, Carlo

    2012-10-01

    Rotary kiln incinerators and cement kilns are two energy intensive processes, requiring high temperatures that can be obtained by the combustion of fossil fuel. In both processes, fossil fuel is often substituted by high or medium calorific waste to avoid resource depletion and to save costs. Two types of industrial calorific waste streams are considered: automotive shredder residue (ASR) and meat and bone meal (MBM). These waste streams are of current high interest: ASR must be diverted from landfill, while MBM can no longer be used for cattle feeding. The environmental impact of the incineration of these waste streams is assessed and compared for both a rotary kiln and a cement kiln. For this purpose, data from an extensive emission inventory is applied for assessing the environmental impact using two different modeling approaches: one focusing on the impact of the relevant flows to and from the process and its subsystems, the other describing the change of environmental impact in response to these physical flows. Both ways of assessing emphasize different aspects of the considered processes. Attention is paid to assumptions in the methodology that can influence the outcome and conclusions of the assessment. It is concluded that for the incineration of calorific wastes, rotary kilns are generally preferred. Nevertheless, cement kilns show opportunities in improving their environmental impact when substituting their currently used fuels by more clean calorific waste streams, if this improvement is not at the expense of the actual environmental impact.

  6. Full scale treatment of ASR wastes in a modified rotary kiln.

    PubMed

    Mancini, G; Viotti, P; Luciano, A; Raboni, M; Fino, D

    2014-11-01

    A plant, designed for the thermo-valorisation of tyres, was specifically modified in order to treat Automobile Shredder Residue (ASR). Results from two full-scale combustion experiments, carried out on large ASR feeding lots (thousands of tons) indicate the proposed technology as a potential route to help the fulfilling of impending 95% reuse and recovery target set by the End of life Vehicle (ELV) Directive (January 2015). The paper describes the main operational troubleshot occurred during the first experiment (emissions at the stack out of regulatory limits and problems of clogging on the conveyer belt) and the consequent upgrading solutions (pre-treatment, introduction of waste double low-flow screw feeder and a cyclone prior to the main fan, modification of rotatory kiln inlet) adopted to allow, during the second long-term experiment, a continuous basis operation of the plant in full compliance with the discharge limit to the atmosphere. Characterization of both ASR and combustion residues allowed to quantify a 18% of combustion residues as not dangerous waste while only the 2% as hazardous one. A pre-treatment for the reduction of fines in the ASR was recommended in order to achieve the required energy recovery efficiency.

  7. Concentrations of metals associated with mining waste in sediments, biofilm, benthic macroinvertebrates, and fish from the Coeur d'Alene River Basin, Idaho

    USGS Publications Warehouse

    Farag, A.M.; Woodward, D.F.; Goldstein, J.N.; Brumbaugh, W.; Meyer, J.S.

    1998-01-01

    Arsenic, Cd, Cu, Pb, Hg, and Zn were measured in sediments, biofilm, benthic macroinvertebrates, and fish from the Coeur d'Alene (CDA) River to characterize the pathway of metals transfer between these components. Metals enter the CDA Basin via tributaries where mining activities have occurred. In general, the ranking of food-web components from the greatest to smallest concentrations of metals was as follows: biofilm (the layer of abiotic and biotic material on rock surfaces) and sediments > invertebrates > whole fish. Elevated Pb was documented in invertebrates, and elevated Cd and Zn were documented in sediment and biofilm approximately 80 km downstream to the Spokane River. The accumulation of metals in invertebrates was dependent on functional feeding group and shredders-scrapers that feed on biofilm accumulated the largest concentrations of metals. Although the absolute concentrations of metals were the largest in biofilm and sediments, the metals have accumulated in fish approximately 50 km downstream from Kellogg, near the town of Harrison. While metals do not biomagnify between trophic levels, the metals in the CDA Basin are bioavailable and do biotransfer. Trout less than 100 mm long feed exclusively on small invertebrates, and small invertebrates accumulate greater concentrations of metals than large invertebrates. Therefore, early-lifestage fish may be exposed to a larger dose of metals than adults.

  8. Emissions of PCDD/Fs, PBDD/Fs, dioxin like-PCBs and PAHs from a cement plant using a long-term monitoring system.

    PubMed

    Conesa, Juan A; Ortuño, Nuria; Abad, Esteban; Rivera-Austrui, Joan

    2016-11-15

    The aim of the present work was to assess the emission of different persistent organic pollutants from a cement plant over a period of one year, under normal operational conditions. Thus, a long-term sampling device was installed in the clinker kiln stack of the cement plant. The factory uses petroleum coke as primary fuel, but also alternative fuels such as solid recovered fuel (SRF), automotive shredder residue (ASR), sewage sludge, waste tires, and meat and bone meal (MBM) wastes, with an energy substitution level of about 40%. Both PCDD/Fs (together with dl-PCBs) and PBDD/Fs were continuously sampled, with a total of ten samples collected in 2-4week periods. Also, PAHs were sampled during one-week periods, in order to evaluate their emissions in three different samples. The emission levels throughout the year were much lower than the set legal limits in all substances, being <10pgI-TEQ/Nm(3) in the case of PCDD/Fs. The data obtained allowed calculation of updated emission factors for the cement sector, which were 8.5ng I-TEQ/ton clinker for PCDD/Fs and 3.2ng WHO-TEQ/ton clinker for PCBs. With respect to the congener distribution, 2,3,7,8-TCDF accounts for 60 to 68% of the total toxicity for PCDD/Fs, and in PBDD/F emissions, a clear predominance of octa-substituted species (both dioxin and furan) was found. PMID:27405517

  9. Environmental impact of incineration of calorific industrial waste: rotary kiln vs. cement kiln.

    PubMed

    Vermeulen, Isabel; Van Caneghem, Jo; Block, Chantal; Dewulf, Wim; Vandecasteele, Carlo

    2012-10-01

    Rotary kiln incinerators and cement kilns are two energy intensive processes, requiring high temperatures that can be obtained by the combustion of fossil fuel. In both processes, fossil fuel is often substituted by high or medium calorific waste to avoid resource depletion and to save costs. Two types of industrial calorific waste streams are considered: automotive shredder residue (ASR) and meat and bone meal (MBM). These waste streams are of current high interest: ASR must be diverted from landfill, while MBM can no longer be used for cattle feeding. The environmental impact of the incineration of these waste streams is assessed and compared for both a rotary kiln and a cement kiln. For this purpose, data from an extensive emission inventory is applied for assessing the environmental impact using two different modeling approaches: one focusing on the impact of the relevant flows to and from the process and its subsystems, the other describing the change of environmental impact in response to these physical flows. Both ways of assessing emphasize different aspects of the considered processes. Attention is paid to assumptions in the methodology that can influence the outcome and conclusions of the assessment. It is concluded that for the incineration of calorific wastes, rotary kilns are generally preferred. Nevertheless, cement kilns show opportunities in improving their environmental impact when substituting their currently used fuels by more clean calorific waste streams, if this improvement is not at the expense of the actual environmental impact. PMID:22739430

  10. Longitudinal variation in the composition of the benthic macroinvertebrate fauna of a typical North coast Jamaican river.

    PubMed

    Hyslop, Eric J; Hunte-Brown, Meshagae

    2012-03-01

    Benthic macroinvertebrate fauna plays a major role in river ecosystems, especially those of tropical islands. Since there is no information on the distribution of benthic invertebrates along a Jamaican river, we report here on the composition of the benthic fauna of the Buff Bay river, on the Northern coast of Jamaica. A total of 14 samples were collected from five sites, using kick nets and a Surber sampler, between May 1997 and October 1998. We also examined the applicability of the rhithron/potamon model, and some of the premises of the River Continuum Concept (RCC) in relation to the distribution of invertebrate taxa. The results showed a total of 38 taxa of identified invertebrates. A group of dominant taxa, composed mainly of immature stages of insects, occurred at all sites. Two notable characteristics of the river were the absence of a true potamonic fauna and the low representation of the shredder functional feeding group in the community We conclude that, while there was minor variation in the composition of the benthic macroinvertebrate fauna among the sites, this was a response to local conditions within the river system. The characteristics of the community did not conform to either of the models.

  11. Full scale treatment of ASR wastes in a modified rotary kiln.

    PubMed

    Mancini, G; Viotti, P; Luciano, A; Raboni, M; Fino, D

    2014-11-01

    A plant, designed for the thermo-valorisation of tyres, was specifically modified in order to treat Automobile Shredder Residue (ASR). Results from two full-scale combustion experiments, carried out on large ASR feeding lots (thousands of tons) indicate the proposed technology as a potential route to help the fulfilling of impending 95% reuse and recovery target set by the End of life Vehicle (ELV) Directive (January 2015). The paper describes the main operational troubleshot occurred during the first experiment (emissions at the stack out of regulatory limits and problems of clogging on the conveyer belt) and the consequent upgrading solutions (pre-treatment, introduction of waste double low-flow screw feeder and a cyclone prior to the main fan, modification of rotatory kiln inlet) adopted to allow, during the second long-term experiment, a continuous basis operation of the plant in full compliance with the discharge limit to the atmosphere. Characterization of both ASR and combustion residues allowed to quantify a 18% of combustion residues as not dangerous waste while only the 2% as hazardous one. A pre-treatment for the reduction of fines in the ASR was recommended in order to achieve the required energy recovery efficiency. PMID:25103234

  12. Novel synthesis and applications of Thiomer solidification for heavy metals immobilization in hazardous ASR/ISW thermal residue.

    PubMed

    Baek, Jin Woong; Mallampati, Srinivasa Reddy; Park, Hung Suck

    2016-03-01

    The present paper reports the novel synthesis and application of Thiomer solidification for heavy metal immobilization in hazardous automobile shredder residues and industrial solid waste (ASR/ISW) thermal residues. The word Thiomer is a combination of the prefix of a sulfur-containing compound "Thio" and the suffix of "Polymer" meaning a large molecule compound of many repeated subunits. To immobilize heavy metals, either ASR/ISW thermal residues (including bottom and fly ash) was mixed well with Thiomer and heated at 140°C. After Thiomer solidification, approximately 91-100% heavy metal immobilization was achieved. The morphology and mineral phases of the Thiomer-solidified ASR/ISW thermal residue were characterized by field emission-scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray diffraction (XRD), which indicated that the amounts of heavy metals detectable on the ASR/ISW thermal residue surface decreased and the sulfur mass percent increased. XRD indicated that the main fraction of the enclosed/bound materials on the ASR/ISW residue contained sulfur associated crystalline complexes. The Thiomer solidified process could convert the heavy metal compounds into highly insoluble metal sulfides and simultaneously encapsulate the ASR/ISW thermal residue. These results show that the proposed method can be applied to the immobilization of ASR/ISW hazardous ash involving heavy metals. PMID:26777552

  13. Providing solutions to energy and environmental problems. Quarterly report, January 1--March 31, 1997

    SciTech Connect

    Not Available

    1997-09-01

    Summaries are presented for the following tasks: Development and demonstration of a practical electric downhole steam generator for thermal recovery of heavy oil and tar; Wetting behavior of selected crude oil/brine/rock systems; Coal gasification, power generation and product market study; Impact of leachate from Clean Coal Technology waste on the stability of clay liners; Investigation of coprocessing heavy oil, automobile shredder residue, and coal; Injection into coal seams for simultaneous CO{sub 2} mitigation and enhanced recovery of coalbed methane; Optimization of carbonizer operations in the FMC coke process; Chemical sensor and field screening technology development; Demonstration of the Koppelman Series C process using a batch test unit with Powder River Basin coal as feed; Remote chemical sensor development; Market assessment and technical feasibility study of PFBC ash use; Solid state NMR analysis of naturally and artificially matured kerogens; Contained recovery of oily wastes field demonstration with Bell Lumber and Pole; B Series pilot plant tests; In-situ treatment of manufactured gas plant contaminated soils; Development and demonstration of a wood-fired gas turbine system; Solid state NMR analysis of Mowry Formation shale from different sedimentary basins; Acid mine drainage prevention, control, and treatment development for the Stockett/Sand Coulee Area; PERF dispersion modeling project, Phase 2; Field testing of the TaBoRR Process using the asphalt and dry bottoms configurations; and Validation of a new soil VOC sampler.

  14. [Feeding habits of immature individuals of Ephemeroptera, Plecoptera, and Trichoptera from middle reaches of a tropical mountain stream].

    PubMed

    Guzmán-Soto, Cristian José; Tamarís-Turizo, Cesar Enrique

    2014-04-01

    Morphological and behavioral aspects of insects allow their grouping in trophic guilds and represent their dependence on food resources. We determined the feeding habits of immature organisms of Ephemeroptera, Plecoptera, and Trichoptera (EPT) from the middle reaches of Gaira stream (Sierra Nevada de Santa Marta, Colombia), using gut content analysis. We identified 13 EPT genera, but only ten were analyzed for a total of 100 organisms. We describe six food items: animal parts (AP), vascular plant tissue (VPT), microalgae (M), fungi (F), coarse particulate organic matter (CPOM) and fine particulate organic matter (FPOM). Baetodes was determined to be a collector-scraper, since FPOM represented 46.6% of food content, followed by F (38.4%). Chimarra, Leptohyphes, Lachlania, and Thraulodes were categorized as collectors with average proportions of FPOM 86.8%, 93.1%, 93.1% and 93.7%, respectively. Phylloicus, Smicridea and Leptonema were main consumers of VPT and CPOM with proportions of 76.3%, 54.6%, and 62.4%, respectively; while ratios of FPOM were 22.3%, 38.8%, and 32.9%, respectively. While all are detritivores, Phylloicus is functionally classified as shredders and Smicridea and Leptonema as collectors. Atopsyche and Anacroneuria were the only taxa in which AP were observed in high proportions, 57.9% and 58.2%, respectively, for that reason they were classified as predators. The organisms examined consume a wide variability of resources. PMID:25189077

  15. The Source of Bacteria Involved in the Break-Down of Gammarus Pulex Faecal Pellets Using Image Analysis

    NASA Astrophysics Data System (ADS)

    Joyce, P.; Wotton, R.

    2005-05-01

    Bacteria survive passage through the gut of aquatic animals and are implicated in the break-down of POM (such as faecal pellets) in aquatic systems. There is evidence that bacteria that survive gut passage are the cause of the initial break-down of faecal pellets, rather than colonisation by bacteria from the environment. Gammarus is the dominant shredder in lowland permeable catchments ("chalk streams") in England and feeds on allochthonous detritus such as fallen leaves. Gammarus faecal pellets could form important pathways for transfer of organic matter in chalk streams. We incubated Gammarus faecal pellets for 80 days in stream water using combinations of treatments (autoclaving the stream water or pellets; fresh non-autoclaved stream water or pellets; reducing bacterial activity using Gentamicin; combinations of these treatments) to assess the role of surviving and colonising bacteria on the break-down process. Break-down was measured using image analysis. Results show that treatments with fresh pellets show much higher levels of break-down than fully autoclaved controls, treatments with fresh stream water but autoclaved pellets, or treatments with Gentamicin. Bacteria surviving gut passage therefore seem to play a greater role in faecal pellet break-down than those colonising from the environment.

  16. Scrap automotive electronics: A mini-review of current management practices.

    PubMed

    Cucchiella, Federica; D'Adamo, Idiano; Rosa, Paolo; Terzi, Sergio

    2016-01-01

    End-of-life vehicles, together with waste from electric and electronic equipment, are known as an important source of secondary raw materials. For many years, their recovery has allowed the restoring of great amounts of metals for new cars production. This article provides a comprehensive mini-review on the end-of-life vehicles recycling topic between 2000 and 2014, with a particular focus on automotive electronics recycling. In fact, in the last years, experts focused their attention on a better exploitation of automotive shredder residue fraction, but not sufficiently on eventual electronic scraps embedded in it. Hence, studies assessing the value embedded in these scraps are rarely available in literature, causing an important gap in both recycling policies and research. The fact that, at present, the management of electronic control units (the most valuable component among automotive electronic equipment) is, as yet, off the radar in both end-of-life vehicles and waste from electric and electronic equipment Directives demonstrates the theory. Of course, their recycling would not contribute in a relevant way to reach the weighted-based recycling and recovery targets characterising current regulations, but would be very important under a critical raw materials recovery view. Results coming from the literature analysis confirm these assumptions. PMID:26467318

  17. Effects of stream acidification on fungal biomass in decaying beech leaves and leaf palatability.

    PubMed

    Dangles, O; Chauvet, E

    2003-02-01

    We examined the effect of surface water acidification on rates of decomposition, ergosterol concentrations (as a measure of fungal biomass), and palatability to shredders of common beech leaves (Fagus sylvatica L.) in five mountain streams (pH 4.7-7.1). Leaf decomposition was significantly faster in the circumneutral streams (pH 6.4-7.1; k > or = 0.00175 d(-1)), when compared to acidic streams (pH 4.7-4.9; k < or = 0.00100 d(-1)). Fungal biomass showed no particular trend along the acidification gradient except that it peaked earlier in the stream closest to neutrality. Leaf palatability, measured as the feeding activity of the leaf-shredding amphipod Gammarus fossarum Koch, varied with the exposure time in the streams. Except for the higher palatability of leaves exposed during 6 weeks at the highest pH, patterns among streams were mostly similar. These results suggest that reduced processing rates in the most acidic streams were not related to differences in fungal biomass associated with decomposing leaves and that microbial conditioning was only slightly delayed by acidification. Possible effects of low pH and related variables (Ca, Al) on microbial decomposition and detritivorous macroinvertebrates are discussed to clarify the inhibition of beech leaf decomposition in the studied systems.

  18. Ecology of Ephemeroptera, Plecoptera and Trichoptera (Insecta) in Rivers of the Gunung Jerai Forest Reserve: Diversity and Distribution of Functional Feeding Groups

    PubMed Central

    Hamid, Suhaila Ab; Md Rawi, Che Salmah

    2014-01-01

    A field study was performed to describe the functional feeding groups (FFGs) of Ephemeroptera, Plecoptera and Trichoptera (EPT) in the Tupah, Batu Hampar and Teroi Rivers in the Gunung Jerai Forest Reserve (GJFR), Kedah, Malaysia. Twenty-nine genera belonging to 19 families were identified. The EPTs were classified into five FFGs: collector-gatherers (CG), collector-filterers (CF), shredders (SH), scrapers (SC) and predators (P). In this study, CG and CF were the dominant groups inhabiting all three rivers. Ephemeroptera dominated these rivers due to their high abundance, and they were also the CG (90.6%). SC were the lowest in abundance among all groups. Based on the FFGs, the Teroi River was suitable for CG, whereas the Tupah and Batu Hampar Rivers were suitable for CG and CF. The distribution of FFGs differed among the rivers (CG, χ2 = 23.6, p = 0.00; SH, χ2 = 10.02, p = 0.007; P, χ2 = 25.54, p = 0.00; CF, χ2 = 21.95, p = 0.00; SC, χ2 = 9.31, p = 0.01). These findings indicated that the FFGs found in rivers of the GJFR represent high river quality. PMID:25210588

  19. Scrap automotive electronics: A mini-review of current management practices.

    PubMed

    Cucchiella, Federica; D'Adamo, Idiano; Rosa, Paolo; Terzi, Sergio

    2016-01-01

    End-of-life vehicles, together with waste from electric and electronic equipment, are known as an important source of secondary raw materials. For many years, their recovery has allowed the restoring of great amounts of metals for new cars production. This article provides a comprehensive mini-review on the end-of-life vehicles recycling topic between 2000 and 2014, with a particular focus on automotive electronics recycling. In fact, in the last years, experts focused their attention on a better exploitation of automotive shredder residue fraction, but not sufficiently on eventual electronic scraps embedded in it. Hence, studies assessing the value embedded in these scraps are rarely available in literature, causing an important gap in both recycling policies and research. The fact that, at present, the management of electronic control units (the most valuable component among automotive electronic equipment) is, as yet, off the radar in both end-of-life vehicles and waste from electric and electronic equipment Directives demonstrates the theory. Of course, their recycling would not contribute in a relevant way to reach the weighted-based recycling and recovery targets characterising current regulations, but would be very important under a critical raw materials recovery view. Results coming from the literature analysis confirm these assumptions.

  20. Ecological studies of a regulated stream: Huntington River, Emery County, Utah

    SciTech Connect

    Winget, R.N.

    1984-04-30

    A 36.9 x 10/sup 6/ m/sup 3/ reservoir constructed on Huntington River, Emery County, Utah, resulted in changes in physical habitat, water quality, temperature, and flow regime. The greatest changes in physical habitat resulted from: (1) sediment additions from dam and road construction plus erosion of reservoir basin during filling; and (2) changing stream flow from a spring high runoff regime to a moderated flow regime. Elimination of spring nutrient concentration peaks and overall reduction of total dissolved nutrient availability in the river plus moderate reductions in pH were the most apparent water quality changes below the reservoir. Water temperature changes were an increased diurnal and seasonal constancy, summer depression, and winter elevation, generally limited to a 10-12 km reach below the dam. Physical and chemical changes altered macroinvertebrate community structure, with changes greatest near the dam and progressively less as distance downstream increased. Below the dam: (1) more environmentally tolerant taxa increased their dominance; (2) relative numbers of smaller sized individuals increased in relation to larger individuals; and (3) filter feeding, collector/gatherers, and scapers gained an advantage over shredders. Macroinvertebrate taxa with small instar larvae present from late summer to early fall were negatively impacted by the unnaturally high July and August flows. The reservoir became a physical barrier to downstream larval drift and upcanyon and downcanyon immigration of adults, resulting in reduced numbers of several species above and below the reservoir. 50 references, 12 figures, 3 tables.

  1. Jointly sponsored research program quarterly technical progress report, January--March 1994

    SciTech Connect

    Not Available

    1994-08-01

    Progress reports are presented for the following tasks: Development and demonstration of a practical electric downhole steam generator for thermal recovery of heavy oil and tar; wetting behavior of selected crude oil/brine/rock systems; coal gasification, power generation, and product market study; impact of leachate from clean coal technology waste on the stability of clay liners; investigation of coprocessing of heavy oil, automobile shredder residue, and coal; injection into coal seams for simultaneous CO{sub 2} mitigation and enhanced recovery of coalbed methane; optimization of carbonizer operations in the FMC coke process; chemical sensor and field screening technology development; demonstration of the Koppelman ``Series C`` Power River Basin coal as feed; remote chemical sensor development; market assessment and technical feasibility study of PFBC ash use; solid-state NMR analysis and interpretation of naturally and artificially matured kerogens; Crow{trademark} field demonstration with Bell Lumber and Pole; ``B`` series pilot plant tests; and in-situ treatment of manufactured gas plant contaminated soils demonstration program.

  2. Characterisation of polycyclic aromatic hydrocarbons in flue gas and residues of a full scale fluidized bed combustor combusting non-hazardous industrial waste.

    PubMed

    Van Caneghem, J; Vandecasteele, C

    2014-11-01

    This paper studies the fate of PAHs in full scale incinerators by analysing the concentration of the 16 EPA-PAHs in both the input waste and all the outputs of a full scale Fluidized Bed Combustor (FBC). Of the analysed waste inputs i.e. Waste Water Treatment (WWT) sludge, Refuse Derived Fuel (RDF) and Automotive Shredder Residue (ASR), RDF and ASR were the main PAH sources, with phenanthrene, fluoranthene and pyrene being the most important PAHs. In the flue gas sampled at the stack, naphthalene was the only predominant PAH, indicating that the PAHs in FBC's combustion gas were newly formed and did not remain from the input waste. Of the other outputs, the boiler and fly ash contained no detectable levels of PAHs, whereas the flue gas cleaning residue contained only low concentrations of naphthalene, probably adsorbed from the flue gas. The PAH fingerprint of the bottom ash corresponded rather well to the PAH fingerprint of the RDF and ASR, indicating that the PAHs in this output, in contrast to the other outputs, were mainly remainders from the PAHs in the waste inputs. A PAH mass balance showed that the total PAH input/output ratio of the FBC ranged from about 100 to about 2600 depending on the waste input composition and the obtained combustion conditions. In all cases, the FBC was clearly a net PAH sink.

  3. Redefining recycling: Everything is a product

    SciTech Connect

    Quinn, B.

    1995-10-01

    Texas-based Chaparral Steel has redefined recycling, not only in its environmental responses, but in the managerial direction of the company itself. Through Project STAR (Systems and Technology for Advanced Recycling), Chaparral has reduced its resources consumption, enhanced its by-products value and reduced waste in areas ranging from mill scale and solvents to water and energy. Chaparral represents an industry rooted in recycling. Steel is the world`s most recycled material, and electric-arc furnace (EAF) steelmakers rely on recycled material as their primary raw resource. In 1994, the entire US EAF industry produced 35 million tons of steel. Chaparral, one of the largest EAF steelmakers, produced 1.41 million tons that same year, with much of its raw material provided by its on-site automobile shredder. Along with steel, the industry produces huge amounts of waste. Chaparral initiated Project STAR in conjunction with an adjacent cement plant owned and operated by Chaparral`s parent company, Texas Industries, Inc. (TXI). The project mission was to develop synergies between the two facilities to reduce or eliminate hazardous waste generation, create new products, conserve energy and resources and protect the environment. The challenge was to apply technologies that would achieve both environmental and economic objectives that address a number of different waste streams, including hazardous waste.

  4. Impacts of urban landuse on macroinvertebrate communities in southeastern Wisconsin streams

    USGS Publications Warehouse

    Stepenuck, K.F.; Crunkilton, R.L.; Wang, L.

    2002-01-01

    Macroinvertebrates were used to assess the impact of urbanization on stream quality across a gradient of watershed imperviousness in 43 southeastern Wisconsin streams. The percentage of watershed connected imperviousness was chosen as the urbanization indicator to examine impact of urban land uses on macroinvertebrate communities. Most urban land uses were negatively correlated with the Shannon diversity index, percent of pollution intolerant Ephemeroptera, Plecoptera, and Trichoptera individuals, and generic richness. Nonurban land uses were positively correlated with these same metrics. The Hilsenhoff biotic index indicated that stream quality declined with increased urbanization. Functional feeding group metrics varied across a gradient of urbanization, suggesting changes in stream quality. Proportions of collectors and gatherers increased, while proportions of filterers, scrapers, and shredders decreased with increased watershed imperviousness. This study demonstrated that urbanization severely degraded stream macroinvertebrate communities, hence stream quality. Good stream quality existed where imperviousness was less than 8 percent, but less favorable assessments were inevitable where imperviousness exceeded 12 to 20 percent. Levels of imperviousness between 8 and 12 percent represented a threshold where minor increases in urbanization were associated with sharp declines in stream quality.

  5. Hydraulic performance of a full-scale peat and ash biofilter in treatment of industrial landfill leachate.

    PubMed

    Kängsepp, Pille; Mathiasson, Lennart; Dahlblom, Peter; Hogland, William

    2009-08-01

    The purpose of this study was to evaluate the hydraulic performance of a full-scale on-site vertical-flow biofilter, consisting of a mixture of peat and carbon-containing ash, and a 500 m(3) equalization pond prior to the filter-system. The treatment plant was constructed to clean up leachate from an industrial mono-landfill that contained shredder residues of end-of-life vehicles and white goods. With the limited storage capacity of the equalization pond, peak loading rates exceeded up to five to six times the designed daily hydraulic load limit of the biofilter system. Such relatively short overloading events did not negatively affect the purification efficiency. To provide the designed annual irrigation rate on the biofilter of 97 m(3) day(- 1) (or 133 mm day(-1)), with large seasonal variations in precipitation, a relatively large pond would be needed. Calculations showed that a storage volume of about 23 000 m(3) would be sufficient for annual leachate volumes up to about 35 000 m(3). A combination of sprinkler and drip irrigation with straw insulation of the latter made it possible to run the plant continuously even when the ambient air temperature was below zero for more than a month at a time. The grain size distribution of the biofilter medium was noticeably changed after 4 years of usage due to the loading of suspended solids from the leachate and decomposition of the peat, causing reduced hydraulic conductivity. PMID:19423574

  6. Conversion of microwave pyrolysed ASR's char using high temperature agents.

    PubMed

    Donaj, Pawel; Blasiak, Wlodzimierz; Yang, Weihong; Forsgren, Christer

    2011-01-15

    Pyrolysis enables to recover metals and organic feedstock from waste conglomerates such as: automotive shredder residue (ASR). ASR as well as its pyrolysis solid products, is a morphologically and chemically varied mixture, containing mineral materials, including hazardous heavy metals. The aim of the work is to generate fundamental knowledge on the conversion of the organic residues of the solid products after ASR's microwave pyrolysis, treated at various temperatures and with two different types of gasifying agent: pure steam or 3% (v/v) of oxygen. The research is conducted using a lab-scale, plug-flow gasifier, with an integrated scale for analysing mass loss changes over time of experiment, serving as macro TG at 950, 850 and 760 °C. The reaction rate of char decomposition was investigated, based on carbon conversion during gasification and pyrolysis stage. It was found in both fractions that char conversion rate decreases with the rise of external gas temperature, regardless of the gasifying agent. No significant differences between the reaction rates undergoing with steam and oxygen for char decomposition has been observed. This abnormal char behaviour might have been caused by the inhibiting effects of ash, especially alkali metals on char activity or due to deformation of char structure during microwave heating. PMID:20940079

  7. Vegetative regeneration capacities of five ornamental plant invaders after shredding.

    PubMed

    Monty, Arnaud; Eugène, Marie; Mahy, Grégory

    2015-02-01

    Vegetation management often involves shredding to dispose of cut plant material or to destroy the vegetation itself. In the case of invasive plants, this can represent an environmental risk if the shredded material exhibits vegetative regeneration capacities. We tested the effect of shredding on aboveground and below-ground vegetative material of five ornamental widespread invaders in Western Europe that are likely to be managed by cutting and shredding techniques: Buddleja davidii (butterfly bush, Scrophulariaceae), Fallopia japonica (Japanese knotweed, Polygonaceae), Spiraea × billardii Hérincq (Billard's bridewort, Rosaceae), Solidago gigantea (giant goldenrod, Asteraceae), and Rhus typhina L. (staghorn sumac, Anacardiaceae). We looked at signs of vegetative regeneration and biomass production, and analyzed the data with respect to the season of plant cutting (spring vs summer), the type of plant material (aboveground vs below-ground), and the shredding treatment (shredded vs control). All species were capable of vegetative regeneration, especially the below-ground material. We found differences among species, but the regeneration potential was generally still present after shredding despite a reduction of growth rates. Although it should not be excluded in all cases (e.g., destruction of giant goldenrod and staghorn sumac aboveground material), the use of a shredder to destroy woody alien plant material cannot be considered as a general management option without significant environmental risk. PMID:25387455

  8. A Stream Multimetric Macroinvertebrate Index (MMI) for the Sand Hills Ecoregion of the Southeastern Plains, USA

    NASA Astrophysics Data System (ADS)

    Kosnicki, Ely; Sefick, Stephen A.; Paller, Michael H.; Jerrell, Miller S.; Prusha, Blair A.; Sterrett, Sean C.; Tuberville, Tracey D.; Feminella, Jack W.

    2016-10-01

    A macroinvertebrate multimetric index is an effective tool for assessing the biological integrity of streams. However, data collected under a single protocol may not be available for an entire region. We sampled macroinvertebrates from the full extent of the Sand Hills ecoregion Level IV of the Southeastern Plains with a standard protocol during the summers of 2010-2012. We evaluated the performance of 94 metrics through a series of screening criteria and built 48 macroinvertebrate multimetric indexs with combinations of the best performing metrics, representing richness, habit, functional feeding guild, sensitivity, and community composition. A series of narrative-response tests for each macroinvertebrate multimetric index was used to find the best performing macroinvertebrate multimetric index which we called the Sand Hills macroinvertebrate multimetric index. The Sand Hills macroinvertebrate multimetric index consisted of the measures Biotic Index, % Shredder taxa, Clinger taxa2/total taxa, Plecoptera and Trichoptera richness, and Tanytarsini taxa2/Chironomidae taxa. Comparison of the Sand Hills macroinvertebrate multimetric index with existing assessment tools calculated with our data indicated that the Sand Hills macroinvertebrate multimetric index performs at a high level with regard to identifying degraded sites and in its response to stress gradients.

  9. Stream invertebrate community functional responses to deposited sediment

    USGS Publications Warehouse

    Rabeni, C.F.; Doisy, K.E.; Zweig, L.D.

    2005-01-01

    We investigated functional responses of benthic invertebrates to deposited sediment in four Missouri USA streams. In each stream, invertebrates were sampled along continuums of deposited sediment (particles <2 mm in size) from 0 to 100% surface cover in reaches of fairly homogeneous substrate composition, current velocity, and water depths. Correlations, graphical representations, and the cumulative response curves of feeding and habit groups provided strong empirical support for distinct community functional changes due to deposited sediment. Feeding groups were more sensitive to deposited sediment than habit groups. Densities of all the feeding groups decreased significantly with increasing deposited sediment, while relative densities of gatherers increased significantly. Taxa richness also decreased significantly for all the feeding groups except for the shredders. Increases in deposited sediment were related to significant density decreases for only the clingers and sprawlers in the habit group, resulting in significant increases in the relative densities of both burrowers and climbers. Clingers, sprawlers, and swimmers also showed significant decreases in taxa richness. ?? Eawag, 2005.

  10. Model institutional infrastructures for recycling of photovoltaic modules

    SciTech Connect

    Moscowitz, P.D.; Reaven, J.; Fthenakis, V.M.

    1996-07-01

    This paper describes model approaches to designing an institutional infrastructure for the recycling of decommissioned photovoltaic modules; more detailed discussion of the information presented in this paper is contained in Reaven et al., (1996)[1]. The alternative approaches are based on experiences in other industries, with other products and materials. In the aluminum, scrap iron, and container glass industries, where recycling is a long-standing, even venerable practice, predominantly private, fully articulated institutional infrastructures exist. Nevertheless, even in these industries, arrangements are constantly evolving in response to regulatory changes, competition, and new technological developments. Institutional infrastructures are less settled for younger large- scale recycling industries that target components of the municipal solid waste (MSW) stream, such as cardboard and newspaper, polyethylene terephthalate (PET) and high-density polyethylene (HDPE) plastics, and textiles. In these industries the economics, markets, and technologies are rapidly changing. Finally, many other industries are developing projects to ensure that their products are recycled (and recyclable) e.g., computers, non-automotive batteries, communications equipment, motor and lubrication oil and oil filters, fluorescent lighting fixtures, automotive plastics and shredder residues, and bulk industrial chemical wastes. The lack of an an adequate recycling infrastructure, attractive end-markets, and clear the economic incentives, can be formidable impediments to a self- sustaining recycling system.

  11. Direct and indirect effects of an invasive omnivore crayfish on leaf litter decomposition.

    PubMed

    Carvalho, Francisco; Pascoal, Cláudia; Cássio, Fernanda; Sousa, Ronaldo

    2016-01-15

    Invasive alien species (IAS) can disrupt important ecological functions in aquatic ecosystems; however, many of these effects are not quantified and remain speculative. In this study, we assessed the effects of the invasive crayfish Procambarus clarkii (Girard, 1852) on leaf litter decomposition (a key ecosystem process) and associated invertebrates using laboratory and field manipulative experiments. The crayfish had significant impacts on leaf decomposition due to direct consumption of leaf litter and production of fine particulate organic matter, and indirectly due to consumption of invertebrate shredders. The invertebrate community did not appear to recognize P. clarkii as a predator, at least in the first stages after its introduction in the system; but this situation might change with time. Overall, results suggested that the omnivore invader P. clarkii has the potential to affect detritus-based food webs through consumption of basal resources (leaf litter) and/or consumers. Recognizing that this IAS is widespread in Europe, Asia and Africa, and may attain high density and biomass in aquatic ecosystems, our results are important to develop strategies for improving stream ecosystem functioning and to support management actions aiming to control the invasive omnivore P. clarkii. PMID:26437346

  12. Effects of surface mining on the aquatic insects of Bear Creek, Boyd County, Kentucky

    SciTech Connect

    Adkins, D.A.

    1981-01-01

    The effects of surface mining on the aquatic insect community of Bear Creek, Boyd County, Kentucky, were examined. Sampling stations were established above the mine, near the mine and below the mine and selected biological and physiochemical factors were examined at these stations. Station 3 (above mine) had a higher pH, higher alkalinity, lower mineral hardness, less siltation and less ferric hydroxide deposition than either Station 2 (at mine) or Station 1 (below mine). The greatest number of specimens (81%) was collected at Station 3. There were 19 mayfly and stonefly taxa represented at Station 3. The Shannon-Weaver diversity index was significantly higher (P < 0.05) at Station 3 than at either Station 1 or Station 2. Examination of trophic relationships showed that shredders (chew and mine vascular plant tissue) were the most abundant group at Station 3, which may have been due to less ferric hydroxide deposition and thereby more vascular plant tissue available. Station 2 (at mine) had the least number of taxa collected, the lowest Shannon-Weaver diversity index value and predators were the most important (Importance Value) trophic group. Station 1 (below mine) was intermediate between Station 2 and Station 3, i.e., it seemed to be a recovery zone where the number of taxa collected began to increase and the physiochemical parameter values began to approach those of Station 3.

  13. [Impacts of urbanization on the water quality and macrobenthos community structure of the tributaries in middle reach of Qiantang River, East China].

    PubMed

    Liu, Dong-Xiao; Yu, Hai-Yan; Liu, Shuo-Ru; Hu, Zun-Ying; Yu, Jian; Wang, Bei-Xin

    2012-05-01

    The 59 1st-3rd order tributaries in the middle reach of Qiantang River are negatively affected by different intensities of urbanization. In April 2010, an investigation was conducted on the water bodies' physical and chemical properties and macrobenthos communities of the tributaries, with the relationships between the tributaries' water quality and biological communities and the percentage of ground surface impervious area (PIA), an indicator of urbanization intensity. The Spearman correlation analysis showed that the water bodies' NH(4+)-N, PO4(3-)-P, TP, COD(Mn), conductivity, width, depth, and fine sand/silt ratio were positively correlated with PIA, and negatively correlated with forest land area. The fitted nonlinear regression equations revealed that all the test macro-benthic invertebrate's parameters had significant relationships with PIA, of which, the total number of taxa, Shannon diversity index, richness index, EPT (%), predators (%), shredders (%), filterers (%) and scrapers (%) were negatively correlated to PIA but positively correlated to forest land area, and the BI, collectors (%), tolerance taxa (%) and oligochaeta (%) were positively correlated to the PIA. Our study indicated that under the impact of urbanization, these tributaries presented the common features of degradation, i. e., high concentrations of nitrogen and phosphorus, degradation of physical habitat, disappearance of pollution-sensitive macro-benthic invertebrate species, and dramatic increase of pollution-tolerant species individuals.

  14. Effects of fungicides on decomposer communities and litter decomposition in vineyard streams.

    PubMed

    Fernández, Diego; Voss, Katharina; Bundschuh, Mirco; Zubrod, Jochen P; Schäfer, Ralf B

    2015-11-15

    Large amounts of fungicides are applied globally and partly enter freshwater ecosystems. A few laboratory studies examined their effects on decomposer communities and the ecosystem process of litter decomposition (LD), whereas the field situation remains largely unknown. We conducted a field study with 17 stream sites in a German vineyard area where fungicides represent the dominant pest control agent. Passive samplers were used to monitor 15 fungicides and 4 insecticides in streams and their toxicity was described using the toxic unit approach, whereas sediment samples were taken to characterise total copper concentrations. Microbial and leaf-shredding invertebrate community composition and related LD rates were assessed at each site. The structure of microbial and shredder communities as well as fungal biomass changed along the fungicide toxicity gradient. The changes in microbial endpoints were associated with a reduction of microbial LD rate of up to 40% in polluted streams. By contrast, neither the invertebrate LD rate nor in-situ measured gammarid feeding rates correlated with fungicide toxicity, but both were negatively associated with sediment copper concentrations. A subsequent laboratory experiment employing field fungicide concentrations suggested that the microbial community changes are causal. Overall, our results suggest that fungicides can affect LD under field conditions.

  15. Longitudinal Changes in Physical Habitat and Macroinvertebrate Assemblages Along a Neotropical Stream Continuum

    NASA Astrophysics Data System (ADS)

    Colon-Gaud, C.; Whiles, M. R.

    2005-05-01

    Information on the structure and function of upland Neotropical streams is lacking compared to many other regions. We examined habitat characteristics and macroinvertebrate assemblages along an 8-km stretch of a stream originating on the continental divide in central Panama in order to examine patterns along a stream continuum. Wetted width and discharge ranged from 1 m and 18 L/s, respectively in the uppermost headwaters to 12 m and 1,580 L/s, respectively at the lowest reach examined. Percent substrate composition showed a decrease in fine particle sizes from upper headwater reaches (38%) to the lowest reach (10%). A total of 61 macroinvertebrate taxa were identified along the continuum, with more taxa present in lower reaches (45) compared to headwaters (28), but responses of individual groups varied. Trichoptera, Ephemeroptera, and Diptera richness increased from headwaters to the lowest site, whereas Hemiptera and Coleoptera richness decreased along the gradient. Collector-gatherers and predators were the dominant functional groups (~70% of total abundance) and changed little across sites. Shredder abundance was highest in headwaters (15% of total), while scrapers (20%) and collector/filterers (11%) peaked in the lower reaches. These patterns suggest that upland streams in this region follow basic tenets of the River Continuum Concept.

  16. Influence of operational conditions, waste input and ageing on contaminant leaching from waste incinerator bottom ash: a full-scale study.

    PubMed

    Hyks, Jiri; Astrup, Thomas

    2009-08-01

    Leaching of metals and Cl from fresh, naturally aged, and lab-scale aged bottom ashes generated during full-scale incineration experiments with different operational conditions (OC) and waste input (WI) was assessed. Although significant differences in the bulk contents of the generated bottom ashes were observed between the individual experiments, addition of 5.5 wt.% PVC, 11.1 wt.% chromated-copper-arsenate impregnated wood, 14.2 wt.% automotive shredder residue, 1.6 wt.% shoes, and 0.5 wt.% batteries to the normal municipal solid waste received at the incinerator (in six individual experiments) had no significant effect on metal leaching from the bottom ash. Likewise, changes in OC (furnace oxygen level and air distribution) could not be correlated to changes in leaching. The effects on metal leaching from ageing were generally larger than the effects from changes in OC and WI. Ash ageing caused a significant decrease in leaching of Cu, Zn, and Pb while leaching of Sb and particularly Cr increased. For Cl, a clear correlation between the bulk contents and leaching was observed for bottom ash generated in experiments with changes in WI. Comparison of leaching data obtained in this study with leaching from "typical" aged Danish bottom ash revealed no significant differences when the typical variations in leaching data over time and between different Danish incinerators were accounted. Generally, this indicates that metal leaching from bottom ash is not sensitive to limited changes in WI and OC as suggested in this paper, only Cl(-) leaching appeared to be affected. PMID:19595431

  17. Full-scale incineration-system demonstration at the Naval Battalion Construction Center, Gulfport, Mississippi. Volume 6. Soil excavation. Final report, Sep 86-Feb 89

    SciTech Connect

    Deiro, S.W.

    1991-07-01

    During the third phase of the NCBC Demonstration Project, 1,006 20 by 20-foot plots were excavated from a depth of 3 inches up to as much as 51 inches. The total soil excavated from these plots was approximately 15,000 cu. d. The equipment used in the soil excavation task were a bulldozer, front-end loader, dump truck, asphalt mill (planer), and track hoe. Air monitoring was performed at all times during excavation to minimize the possibility of movement of contaminated dust offsite. Immediately after the excavation of a plot, a bottom-of-hole sample was taken from the plot and shipped to an analytical laboratory for 2,3,7,8-TCDD analysis. As the soil was excavated, it was placed in one of three soil storage tents located near the incinerator. A material handler, using a front-end loader, transferred the soil from the storage tents to the weigh hopper/shredder unit where it was weighed, shredded into small pieces, and dropped onto a covered feed conveyor. The covered conveyor belt carried the soil to the feed hopper where the auger fed the soil into the rotary kiln incinerator. The soil in the rotary kiln was subjected to a minimum temperature of 1,450 F for 20 to 40 minutes to volatilize the organics. At the outlet of the kiln, the burned solids (ash) fell into a water quench tank, while the gases and submicron particulate flowed upward through the cyclones and crossover duct to the Secondary Combustion Chamber.

  18. Exposure and nontarget effects of transgenic Bt corn debris in streams.

    PubMed

    Jensen, Peter D; Dively, Galen P; Swan, Christopher M; Lamp, William O

    2010-04-01

    Corn (Zea mays L.) transformed with a gene from the bacterium Bacillus thuringiensis (Bt) comprises 49% of all corn in the United States. The input of senesced corn tissue expressing the Bt gene may impact stream-inhabiting invertebrates that process plant debris, especially trichopteran species related to the target group of lepidopteran pests. Our goal was to assess risk associated with transgenic corn debris entering streams. First, we show the input of corn tissue after harvest was extended over months in a stream. Second, using laboratory bioassays based on European corn borer [Ostrinia nubilalis (Hübner)], we found no bioactivity of Cry1Ab protein in senesced corn tissue after 2 wk of exposure to terrestrial or aquatic environments. Third, we show that Bt near-isolines modify growth and survivorship of some species of invertebrates. Of the four nontarget invertebrate species fed Bt near-isolines, growth of two closely related trichopterans was not negatively affected, whereas a tipulid crane fly exhibited reduced growth rates, and an isopod exhibited reduced growth and survivorship on the Cry1Ab near-isoline but not on the stacked Cry1Ab + Cry3Bb1 near-isoline. Because of lack of evidence of bioactivity of Bt after 2 wk and because of lack of nontarget effects on the stacked near-isoline, we suggest that tissue-mediated differences, and not the presence of the Cry1Ab protein, caused the different responses among the species. Overall, our results provide evidence that adverse effects to aquatic nontarget shredders involve complex interactions arising from plant genetics and environment that cannot be ascribed to the presence of Cry1Ab proteins.

  19. Influence of operational conditions, waste input and ageing on contaminant leaching from waste incinerator bottom ash: a full-scale study.

    PubMed

    Hyks, Jiri; Astrup, Thomas

    2009-08-01

    Leaching of metals and Cl from fresh, naturally aged, and lab-scale aged bottom ashes generated during full-scale incineration experiments with different operational conditions (OC) and waste input (WI) was assessed. Although significant differences in the bulk contents of the generated bottom ashes were observed between the individual experiments, addition of 5.5 wt.% PVC, 11.1 wt.% chromated-copper-arsenate impregnated wood, 14.2 wt.% automotive shredder residue, 1.6 wt.% shoes, and 0.5 wt.% batteries to the normal municipal solid waste received at the incinerator (in six individual experiments) had no significant effect on metal leaching from the bottom ash. Likewise, changes in OC (furnace oxygen level and air distribution) could not be correlated to changes in leaching. The effects on metal leaching from ageing were generally larger than the effects from changes in OC and WI. Ash ageing caused a significant decrease in leaching of Cu, Zn, and Pb while leaching of Sb and particularly Cr increased. For Cl, a clear correlation between the bulk contents and leaching was observed for bottom ash generated in experiments with changes in WI. Comparison of leaching data obtained in this study with leaching from "typical" aged Danish bottom ash revealed no significant differences when the typical variations in leaching data over time and between different Danish incinerators were accounted. Generally, this indicates that metal leaching from bottom ash is not sensitive to limited changes in WI and OC as suggested in this paper, only Cl(-) leaching appeared to be affected.

  20. Incinerator performance: effects of changes in waste input and furnace operation on air emissions and residues.

    PubMed

    Astrup, Thomas; Riber, Christian; Pedersen, Anne Juul

    2011-10-01

    Waste incineration can be considered a robust technology for energy recovery from mixed waste. Modern incinerators are generally able to maintain relatively stable performance, but changes in waste input and furnace operation may affect emissions. This study investigated how inorganic air emissions and residue composition at a full-scale incinerator were affected by known additions of specific waste materials to the normal municipal solid waste (MSW) input. Six individual experiments were carried out (% ww of total waste input): NaCl (0.5%), shoes (1.6%), automobile shredder waste (14%), batteries (0.5%), poly(vinyl chloride) (5.5%) and chromate-cupper-arsenate impregnated wood (11%). Materials were selected based on chemical composition and potential for being included or excluded from the waste mix. Critical elements in the waste materials were identified based on comparison with six experiments including 'as-large-as-possible' changes in furnace operation (oxygen levels, air supply and burnout level) only using normal MSW as input. The experiments showed that effects from the added waste materials were significant in relation to: air emissions (in particular As, Cd, Cr, Hg, Sb), element transfer coefficients, and residue composition (As, Cd, Cl, Cr, Cu, Hg, Mo, Ni, Pb, S, Sb, Zn). Changes in furnace operation could not be directly linked to changes in emissions and residues. The results outlined important elements in waste which should be addressed in relation to waste incinerator performance. Likely ranges of element transfer coefficients were provided as the basis for sensitivity analysis of life-cycle assessment (LCA) results involving waste incinerator technologies.

  1. Quantification of the nitrogen cycle in a prairie stream

    USGS Publications Warehouse

    Dodds, Walter K.; Evans-White, Michelle A.; Gerlanc, Nicole M.; Gray, Lawrence; Gudder, Dolly A.; Kemp, Melody J.; Lopez, Amanda L.; Stagliano, David; Strauss, Eric A.; Tank, Jennifer L.; Whiles, Matt R.; Wollheim, Wilfred M.

    2000-01-01

    Nitrogen (N) was added for 35 days in the form of 15NH4Cl to Kings Creek on Konza Prairie, Kansas. Standing stocks of N in key compartments (that is, nutrients, detritus, organisms) were quantified, and the amount of labeled N entering the compartments was analyzed. These data were used to calculate turnover and flux rates of N cycling through the food web, as well as nutrient transformation rates. Inorganic N pools turned over much more rapidly in the water column of this stream than in pelagic systems where comparable measurements have been made. As with other systems, the mass of ammonium was low but it was the key compartment mediating nutrient flux through the ecosystem, whereas dissolved organic N, the primary component of N flux through the system, is not actively cycled. Nitrification was also a significant flux of N in the stream, with rates in the water column and surface of benthos accounting for approximately 10% of the total ammonium uptake. Primary consumers assimilated 67% of the inorganic N that entered benthic algae and microbes. Predators acquired 23% of the N that consumers obtained. Invertebrate collectors, omnivorous crayfish (Orconectes spp.), and invertebrate shredders dominated the N flux associated with primary consumers. Mass balance calculations indicated that at least 23% of the 309 mg of 15N added during the 35 days of release was retained within the 210-m stream reach during the release. Overall, the rates of turnover of N in organisms and organic substrata were significantly greater when C:N was low. This ratio may be a surrogate for biological activity with regard to N flux in streams.

  2. On the ASR and ASR thermal residues characterization of full scale treatment plant.

    PubMed

    Mancini, G; Viotti, P; Luciano, A; Fino, D

    2014-02-01

    In order to obtain 85% recycling, several procedures on Automotive Shredder Residue (ASR) could be implemented, such as advanced metal and polymer recovery, mechanical recycling, pyrolysis, the direct use of ASR in the cement industry, and/or the direct use of ASR as a secondary raw material. However, many of these recovery options appear to be limited, due to the possible low acceptability of ASR based products on the market. The recovery of bottom ash and slag after an ASR thermal treatment is an option that is not usually considered in most countries (e.g. Italy) due to the excessive amount of contaminants, especially metals. The purpose of this paper is to provide information on the characteristics of ASR and its full-scale incineration residues. Experiments have been carried out, in two different experimental campaigns, in a full-scale tyre incineration plant specifically modified to treat ASR waste. Detailed analysis of ASR samples and combustion residues were carried out and compared with literature data. On the basis of the analytical results, the slag and bottom ash from the combustion process have been classified as non-hazardous wastes, according to the EU waste acceptance criteria (WAC), and therefore after further tests could be used in future in the construction industry. It has also been concluded that ASR bottom ash (EWC - European Waste Catalogue - code 19 01 12) could be landfilled in SNRHW (stabilized non-reactive hazardous waste) cells or used as raw material for road construction, with or without further treatment for the removal of heavy metals. In the case of fly ash from boiler or Air Pollution Control (APC) residues, it has been found that the Cd, Pb and Zn concentrations exceeded regulatory leaching test limits therefore their removal, or a stabilization process, would be essential prior to landfilling the use of these residues as construction material.

  3. Top-down and bottom-up processes in grassland and forested streams.

    PubMed

    Nyström, Per; McIntosh, Angus R; Winterbourn, Michael J

    2003-08-01

    The influence of predatory fish on the structure of stream food webs may be altered by the presence of forest canopy cover, and consequent differences in allochthonous inputs and primary production. Eight sites containing introduced brown trout ( Salmo trutta) and eight sites that did not were sampled in the Cass region, South Island, New Zealand. For each predator category, half the sites were located in southern beech (Nothofagus) forest patches (range of canopy cover, 65-90%) and the other half were in tussock grassland. Food resources used by two dominant herbivores-detritivores were assessed using stable isotopes. (13)C/(12)C ratios were obtained for coarse particulate organic matter (CPOM), fine particulate organic matter (FPOM), algal dominated biofilm from rocks, and larvae of Deleatidium (Ephemeroptera) and Olinga (Trichoptera). Total abundance and biomass of macroinvertebrates did not differ between streams with and without trout, but were significantly higher at grassland sites than forested sites. However, taxon richness and species composition differed substantially between trout and no-trout sites, irrespective of whether streams were located in forest or not. Trout streams typically contained more taxa, had low biomass of predatory invertebrates and large shredders, but a high proportion of consumers with cases or shells. The standing stock of CPOM was higher at forested sites, but there was less FPOM and more algae at sites with trout, regardless of the presence or absence of forest cover. The stable carbon isotope range for biofilm on rocks was broad and encompassed the narrow CPOM and FPOM ranges. At trout sites, carbon isotope ratios of Deleatidium, the most abundant invertebrate primary consumer, were closely related to biofilm values, but no relationship was found at no-trout sites where algal biomass was much lower. These results support a role for both bottom-up and top-down processes in controlling the structure of the stream communities

  4. Assessing water source and channel type as factors affecting benthic macroinvertebrate and periphyton assemblages in the highly urbanized Santa Ana River Basin, California

    USGS Publications Warehouse

    Burton, C.A.; Brown, L.R.; Belitz, K.

    2005-01-01

    The Santa Ana River basin is the largest stream system in Southern California and includes a densely populated coastal area. Extensive urbanization has altered the geomorphology and hydrology of the streams, adversely affecting aquatic communities. We studied macroinvertebrate and periphyton assemblages in relation to two categorical features of the highly engineered hydrologic system-water source and channel type. Four water sources were identified-natural, urban-impacted groundwater, urban runoff, and treated wastewater. Three channel types were identified-natural, channelized with natural bottom, and concrete-lined. Nineteen sites, covering the range of these two categorical features, were sampled in summer 2000. To minimize the effects of different substrate types among sites, artificial substrates were used for assessing macroinvertebrate and periphyton assemblages. Physical and chemical variables and metrics calculated from macroinvertebrate and periphyton assemblage data were compared among water sources and channel types using analysis of variance and multiple comparison tests. Macroinvertebrate metrics exhibiting significant (P < 0.05) differences between water sources included taxa and Ephemeroptera-Plecoptera-Trichoptera richness, relative richness and abundance of nonchironomid dipterans, orthoclads, oligochaetes, and some functional-feeding groups such as parasites and shredders. Periphyton metrics showing significant differences between water sources included blue-green algae biovolume and relative abundance of nitrogen heterotrophic, eutrophic, motile, and pollution-sensitive diatoms. The relative abundance of trichopterans, tanytarsini chironomids, noninsects, and filter feeders, as well as the relative richness and abundance of diatoms, were significantly different between channel types. Most physical variables were related to channel type, whereas chemical variables and some physical variables (e.g., discharge, velocity, and channel width) were

  5. Growth and reproductive ecology of the eastern brook trout, Salvelinus fontinalis, in streams of differing vulnerability to acidic atmospheric deposition

    SciTech Connect

    Light, R.W.

    1983-01-01

    Three naturally infertile streams of differing vulnerability to acidic atmospheric deposition were studied to determine the status of their brook trout, Salvelinus fontinalis, populations and associated benthic communities. Of the three streams, Upper Three Runs was judged to be the least fertile, followed by Little Fishing Creek, with Roaring Run being the most fertile. The median weighted pH of acidic deposition impacting the watersheds was 3.8 for Upper Three Runs and 4.0 for Little Fishing Creek and Roaring Run. Brook trout from Roaring Run grew at a similar rate to those from Little Fishing Creek, with trout from Upper Three Runs showing the slowest growth. Roaring Run brook trout also had the highest relative condition of the three streams. Brook trout from Roaring Run and Little Fishing Creek generally matured one year later (age group II) than those from Upper Three Runs. Early maturity may be selected for in Upper Three Runs due to small annual increases in fecundity in higher age groups. Although the data were limited, there was a trend for brook trout from Upper Three Runs to produce fewer and larger ova. Roaring Run had higher volumes of benthos during fall and summer, and higher numbers during fall. Roaring Run and Little Fishing Creek had more, larger crayfish present, which added significantly to the volume of benthos in these streams. Qualitatively, Upper Three Runs had more shredders and fewer scrapers on a volume basis than the other two streams. On a per fish basis, the drift available to the fish in Roaring Run was always highest in volume, and highest in number during fall and spring. The brook trout from Roaring Run therefore had an advantage over those in the other two streams, by having a higher drift available per fish.

  6. Benthic macroinvertebrates along the soil/water interface of the HUMEX lake 1989-1991

    SciTech Connect

    Hargeby, A.; Petersen, R.C. Jr.; Kullberg, A.; Svensson, M. )

    1992-01-01

    The taxonomic composition, abundance, and size distribution of benthic macroinvertebrates were studied at the soil/water interface two years before and the first year after the start of artificial acidification of a small catchment and its humic lake. The macroinvertebrate assemblage consisted mainly of predators; dragonflies (Odonata), damselflies (Zygoptera), net-building caddisflies (Polycentropodidae), diving beetles (Dytiscidae), and water bugs (Hemiptera). It is suggested that benthic and planktonic microcrustaceans are important prey for damselflies and that intraguild predation is important for the structure of the community. The typical bog tarn assemblage did not include snails, mussels, or macrocrustaceans, which are algae and detritus feeders known to be affected by low pH. The only potential herbivores on filaments algae and shredders of coarse detritus were case building caddisflies and the ephemeropteran Leptophlebia vespertina, which were all found in low numbers. If the artificial acidification will eliminate these macroinvertebrates, it will have little impact on attached filaments algae, and on processing of coarse detritus. Although there was a general similarity in taxonomic structure on the two sides, significantly higher numbers of dytiscids (Acilius sulcatus and Ilybius spp.) were consistently found on the experimental side than on the control side through the three years of study. The first year after acidification, the number of Zygoptera was lower on the experimental side than on the control side. The abundance on the control side in this year was, however, also higher than in the previous two years. The size distribution of Coenagrion hastulatum, the dominating zygopteran, showed no difference between lake sides. Significant difference between years indicate, however, that size distribution could be used to detect altered growth conditions. 20 refs., 5 figs., 4 tabs.

  7. On the ASR and ASR thermal residues characterization of full scale treatment plant.

    PubMed

    Mancini, G; Viotti, P; Luciano, A; Fino, D

    2014-02-01

    In order to obtain 85% recycling, several procedures on Automotive Shredder Residue (ASR) could be implemented, such as advanced metal and polymer recovery, mechanical recycling, pyrolysis, the direct use of ASR in the cement industry, and/or the direct use of ASR as a secondary raw material. However, many of these recovery options appear to be limited, due to the possible low acceptability of ASR based products on the market. The recovery of bottom ash and slag after an ASR thermal treatment is an option that is not usually considered in most countries (e.g. Italy) due to the excessive amount of contaminants, especially metals. The purpose of this paper is to provide information on the characteristics of ASR and its full-scale incineration residues. Experiments have been carried out, in two different experimental campaigns, in a full-scale tyre incineration plant specifically modified to treat ASR waste. Detailed analysis of ASR samples and combustion residues were carried out and compared with literature data. On the basis of the analytical results, the slag and bottom ash from the combustion process have been classified as non-hazardous wastes, according to the EU waste acceptance criteria (WAC), and therefore after further tests could be used in future in the construction industry. It has also been concluded that ASR bottom ash (EWC - European Waste Catalogue - code 19 01 12) could be landfilled in SNRHW (stabilized non-reactive hazardous waste) cells or used as raw material for road construction, with or without further treatment for the removal of heavy metals. In the case of fly ash from boiler or Air Pollution Control (APC) residues, it has been found that the Cd, Pb and Zn concentrations exceeded regulatory leaching test limits therefore their removal, or a stabilization process, would be essential prior to landfilling the use of these residues as construction material. PMID:24290536

  8. Baseline Assessment of Fish Communities, Benthic Macroinvertebrate Communities, and Stream Habitat and Land Use, Big Thicket National Preserve, Texas, 1999-2001

    USGS Publications Warehouse

    Moring, J. Bruce

    2003-01-01

    The Big Thicket National Preserve comprises 39,300 hectares in the form of nine preserve units connected by four stream corridor units (with two more corridor units proposed) distributed over the lower Neches and Trinity River Basins of southeastern Texas. Fish and benthic macroinvertebrate data were collected at 15 stream sites (reaches) in the preserve during 1999?2001 for a baseline assessment and a comparison of communities among stream reaches. The fish communities in the preserve were dominated by minnows (family Cyprinidae) and sunfishes (family Centrarchidae). Reaches with smaller channel sizes generally had higher fish species richness than the larger reaches in the Neches River and Pine Island Bayou units of the preserve. Fish communities in geographically adjacent reaches were most similar in overall community structure. The blue sucker, listed by the State as a threatened species, was collected in only one reach?a Neches River reach a few miles downstream from the Steinhagen Lake Dam. Riffle beetles (family Elmidae) and midges (family Chironomidae) dominated the aquatic insect communities at the 14 reaches sampled for aquatic insects in the preserve. The Ephemeroptera, Plecoptera and Trichoptera (EPT) Index, an index sensitive to water-quality degradation, was smallest at the Little Pine Island Bayou near Beaumont reach that is in a State 303(d)-listed stream segment on Little Pine Island Bayou. Trophic structure of the aquatic insect communities is consistent with the river continuum concept with shredder and scraper insect taxa more abundant in reaches with smaller stream channels and filter feeders more abundant in reaches with larger channels. Aquatic insect community metrics were not significantly correlated to any of the stream-habitat or land-use explanatory variables. The percentage of 1990s urban land use in the drainage areas upstream from 12 bioassessment reaches were negatively correlated to the reach structure index, which indicates less

  9. Comparison of macroinvertebrate-derived stream quality metrics between snag and riffle habitats

    USGS Publications Warehouse

    Stepenuck, K.F.; Crunkilton, R.L.; Bozek, Michael A.; Wang, L.

    2008-01-01

    We compared benthic macroinvertebrate assemblage structure at snag and riffle habitats in 43 Wisconsin streams across a range of watershed urbanization using a variety of stream quality metrics. Discriminant analysis indicated that dominant taxa at riffles and snags differed; Hydropsychid caddisflies (Hydropsyche betteni and Cheumatopsyche spp.) and elmid beetles (Optioservus spp. and Stenemlis spp.) typified riffles, whereas isopods (Asellus intermedius) and amphipods (Hyalella azteca and Gammarus pseudolimnaeus) predominated in snags. Analysis of covariance indicated that samples from snag and riffle habitats differed significantly in their response to the urbanization gradient for the Hilsenhoff biotic index (BI), Shannon's diversity index, and percent of filterers, shredders, and pollution intolerant Ephemeroptera, Plecoptera, and Trichoptera (EPT) at each stream site (p ??? 0.10). These differences suggest that although macroinvertebrate assemblages present in either habitat type are sensitive to detecting the effects of urbanization, metrics derived from different habitats should not be intermixed when assessing stream quality through biomonitoring. This can be a limitation to resource managers who wish to compare water quality among streams where the same habitat type is not available at all stream locations, or where a specific habitat type (i.e., a riffle) is required to determine a metric value (i.e., BI). To account for differences in stream quality at sites lacking riffle habitat, snag-derived metric values can be adjusted based on those obtained from riffles that have been exposed to the same level of urbanization. Comparison of nonlinear regression equations that related stream quality metric values from the two habitat types to percent watershed urbanization indicated that snag habitats had on average 30.2 fewer percent EPT individuals, a lower diversity index value than riffles, and a BI value of 0.29 greater than riffles. ?? 2008 American Water

  10. Are insect repellents toxic to freshwater insects? A case study using caddisflies exposed to DEET.

    PubMed

    Campos, Diana; Gravato, Carlos; Quintaneiro, Carla; Koba, Olga; Randak, Tomas; Soares, Amadeu M V M; Pestana, João L T

    2016-04-01

    Stream ecosystems face ever-increasing pressures by the presence of emergent contaminants, such as, personal care products. N, N-diethyl-3-methylbenzamide (DEET) is a synthetic insect repellent that is being found in surface waters environments in concentrations up to 33.4 μg/L. Information concerning DEET's toxicity in the aquatic environment is still limited and focused only on its acute effects on model species. Our main objective was to assess the effects of DEET exposure to a caddisfly non-target species using sub-lethal endpoints. For that, we chose Sericostoma vittatum, an important shredder in Portuguese freshwaters that has been already used in different ecotoxicological assays. Besides acute tests, S. vittatum were exposed during 6 days to a gradient of DEET concentrations (8, 18 and 40.5 mg/L) to assess effects on feeding behaviour and biochemical responses, such as, lipid peroxidation levels (LPO), catalase and acetylcholinesterase (AChE) activities, and also assess effects on energy reserves and consumption. Acute tests revealed a 48 h-LC50 of 80.12 mg/L and DEET exposure caused feeding inhibition with a LOEC of 36.80 mg/L. Concerning the biochemical responses, DEET caused no effects in LPO nor on catalase activity. A non-significant decrease in AChE activity was observed. Regarding energetic reserves, exposure to DEET caused a significant reduction in S. vittatum carbohydrates levels. These results add important information for the risk assessment of insect repellents in the aquatic environment and suggest that reported environmental concentrations of DEET are not toxic to non-target freshwater insects. PMID:26855222

  11. The impact of cattle access on ecological water quality in streams: Examples from agricultural catchments within Ireland.

    PubMed

    Conroy, E; Turner, J N; Rymszewicz, A; O'Sullivan, J J; Bruen, M; Lawler, D; Lally, H; Kelly-Quinn, M

    2016-03-15

    Unrestricted cattle access to rivers and streams represent a potentially significant localised pressure on freshwater systems. However there is no consensus in the literature on the occurrence and extent of impact and limited research has examined the effects on aquatic biota in the humid temperate environment examined in the present study. Furthermore, this is one of the first times that research consider the potential for cattle access impacts in streams of varying water quality in Northern Europe. We investigated the effects of cattle access on macroinvertebrate communities and deposited fine sediment levels, in four rivers of high/good and four rivers of moderate water quality status which drain, low gradient, calcareous grassland catchments in Ireland. We assessed the temporal variability in macroinvertebrates communities across two seasons, spring and autumn. Site specific impacts were evident which appeared to be influenced by water quality status and season. All four high/good water status rivers revealed significant downstream changes in community structure and at least two univariate metrics (total richness and EPT richness together with taxon, E and EPT abundance). Two of the four moderate water status rivers showed significant changes in community structure, abundance and richness metrics and functional feeding groups driven in the main by downstream increases in collectors/gatherers, shredders and burrowing taxa. These two moderate water status rivers had high or prolonged livestock activity. In view of these findings, the potential for some of these sites to achieve at least high/good water quality status, as set out in the EU Water Framework Directive, may be compromised. The results presented highlight the need for additional research to further define the site specific factors and livestock management practices, under different discharge conditions, that increase the risk of impact on aquatic ecology due to these cattle-river interactions.

  12. A hairy case: The evolution of filtering carnivorous Drusinae (Limnephilidae, Trichoptera)

    PubMed Central

    Kučinić, Mladen; Oláh, János; Bálint, Miklós; Previšić, Ana; Keresztes, Lujza; Pauls, Steffen U.; Waringer, Johann

    2016-01-01

    The caddisfly subfamily Drusinae BANKS comprises roughly 100 species inhabiting mountain ranges in Europe, Asia Minor and the Caucasus. A 3–gene phylogeny of the subfamily previously identified three major clades that were corroborated by larval morphology and feeding ecologies: scraping grazers, omnivorous shredders and filtering carnivores. Larvae of filtering carnivores exhibit unique head capsule complexities, unknown from other caddisfly larvae. Here we assess the species-level relationships within filtering carnivores, hypothesizing that head capsule complexity is a derived state based on the simple shapes observed in the other feeding groups. We summarize the current taxonomy of the group, describe Drusus krpachi sp. nov., and D. puskasi sp. nov., and present a larval key to filtering carnivorous Drusinae. We infer relationships of all known filtering carnivorous Drusinae and 34 additional Drusinae species using Bayesian species tree analysis and concatenated Bayesian phylogenetic analysis of 3805 bp of sequence data from six gene regions (mtCOI5-P, mtCOI3-P, 16S mrDNA, CADH, WG, 28S nrDNA), morphological cladistics from 308 characters, and a total evidence analysis. All analyses support monophyly of the three feeding ecology groups but fail to fully resolve internal relationships. Within filtering carnivores, variation in head setation and frontoclypeus structure may be associated with progressive niche adaptation, with less complex species recovered at a basal position. We propose that diversification of complex setation and frontoclypeus shape represents a recent evolutionary development, hypothetically enforcing speciation and niche specificity within filtering carnivorous Drusinae. PMID:26265260

  13. The Carolina Bay Restoration Project - Status Report II 2000-2004.

    SciTech Connect

    Barton, Christopher

    2006-07-13

    A Wetlands Mitigation Bank was established at SRS in 1997 as a compensatory alternative for unavoidable wetland losses. Prior to restoration activities, 16 sites included in the project were surveyed for the SRS Site Use system to serve as a protective covenant. Pre-restoration monitoring ended in Fall 2000, and post restoration monitoring began in the Winter/Spring of 2001. The total interior harvest in the 16 bays after harvesting the trees was 19.6 ha. The margins in the opencanopy, pine savanna margin treatments were thinned. Margins containing areas with immature forested stands (bay 5184 and portions of bay 5011) were thinned using a mechanical shredder in November 2001. Over 126 hectares were included in the study areas (interior + margin). Planting of two tree species and the transplanting of wetland grass species was successful. From field surveys, it was estimated that approximately 2700 Nyssa sylvatica and 1900 Taxodium distichum seedlings were planted in the eight forested bays resulting in an average planting density of ≈ 490 stems ha-1. One hundred seedlings of each species per bay (where available) were marked to evaluate survivability and growth. Wetland grass species were transplanted from donor sites on SRS to plots that ranged in size from 100 – 300 m2, depending on wetland size. On 0.75 and 0.6 meter centers, respectively, 2198 plugs of Panicum hemitomon and 3021 plugs Leersia hexandra were transplanted. New shoots originating from the stumps were treated with a foliar herbicide (Garlon® 4) during the summer of 2001 using backpack sprayers. Preliminary information from 2000-2004 regarding the hydrologic, vegetation and faunal response to restoration is presented in this status report. Post restoration monitoring will continue through 2005. A final report to the Mitigation Bank Review Team will be submitted in mid-2006.

  14. The Carolina Bay Restoration Project - Final Report 2000-2006.

    SciTech Connect

    Barton, Christopher

    2007-12-15

    A Wetlands Mitigation Bank was established at SRS in 1997 as a compensatory alternative for unavoidable wetland losses. Prior to restoration activities, 16 sites included in the project were surveyed for the SRS Site Use system to serve as a protective covenant. Pre-restoration monitoring ended in Fall 2000, and post restoration monitoring began in the Winter/Spring of 2001. The total interior harvest in the 16 bays after harvesting the trees was 19.6 ha. The margins in the opencanopy, pine savanna margin treatments were thinned. Margins containing areas with immature forested stands (bay 5184 and portions of bay 5011) were thinned using a mechanical shredder in November 2001. Over 126 hectares were included in the study areas (interior + margin). Planting of two tree species and the transplanting of wetland grass species was successful. From field surveys, it was estimated that approximately 2700 Nyssa sylvatica and 1900 Taxodium distichum seedlings were planted in the eight forested bays resulting in an average planting density of ≈ 490 stems ha-1. One hundred seedlings of each species per bay (where available) were marked to evaluate survivability and growth. Wetland grass species were transplanted from donor sites on SRS to plots that ranged in size from 100 – 300 m2, depending on wetland size. On 0.75 and 0.6 meter centers, respectively, 2198 plugs of Panicum hemitomon and 3021 plugs Leersia hexandra were transplanted. New shoots originating from the stumps were treated with a foliar herbicide (Garlon® 4) during the summer of 2001 using backpack sprayers. Preliminary information from 2000-2004 regarding the hydrologic, vegetation and faunal response to restoration is presented in this status report.

  15. A Characterization and Evaluation of Coal Liquefaction Process Streams

    SciTech Connect

    G. A. Robbins; R. A. Winschel; S. D. Brandes

    1998-06-09

    CONSOL characterized 38 process strea m samples from HTI Run PB- 04, in which Black Thunder Mine Coal, Hondo vacuum resid, autom obile shredder residue (ASR), and virgin plastics were used as liquefaction feedstocks with dispersed catalyst. A paper on kinetic modeling of resid reactivity was presented at the DOE Coal Lique -faction and Solid Fuels Contractors Review Conference, September 3- 4, 1997, i n Pittsburgh, PA. The paper, "The Reactivity of Direct Coal Liquefaction Resids", i s appended (Appendix 1). Three papers on characterization of samples from coal/ resid/ waste p lastics co- liquefaction were presented or submitted for presen tation at conferences. Because of their similarity, only one of the papers is appended to this report. The paper, "Characterization o f Process Samples From Co- Liquefaction of Coal and Waste Polymers", (Appendix 2) was presented at the DOE Coal Liquefaction and Solid Fuels C ontractors Review Conference, September 3- 4, 1997, in Pittsburgh, PA. The paper, "Characterization of Process Stream Samples From Bench- Scale Co -Liquefaction Runs That Utilized Waste Polymers as Feedstocks" was presented at the 214th National Meeting of the Ameri can Chemical Society, September 7- 11, 1997, in Las Vegas, NV. The paper, "Characterization of Process Oils from Coal/ Waste Co- Liquefaction" wa s submitted for presentation at the 14th Japan/ U. S. Joint Technical Meeting on Coa l Liquefaction and Materials for Coal Liquefaction on October 28, 1997, in Tokyo, Japan. A joint Burns and Roe Services Corp. and CONSOL pap er on crude oil assays of product oils from HTI Run PB- 03 was presented at the DOE Coal Liquefaction and Solid Fuel s Contractors Review Conference, September 3- 4, 1997, in Pittsburgh, PA. The paper , "Characterization of Liquid Products from All- Slurry Mode Liquefaction", is appende d (Appendix 3).

  16. Strategies of Gammarus pulex L. to cope with arsenic--Results from speciation analyses by IC-ICP-MS and XAS micro-mapping.

    PubMed

    Schaller, Jörg; Koch, Iris; Caumette, Guilhem; Nearing, Michelle; Reimer, Kenneth J; Planer-Friedrich, Britta

    2015-10-15

    The invertebrate shredder Gammarus pulex L. is a key species for aquatic carbon turnover via litter decomposition and can thrive in high-arsenic (As) environments. To understand their strategies for coping with increased As concentrations while fulfilling their ecosystem functions, we analyzed the As concentration and speciation in their aquatic habitat and in leaves with heterotrophic biofilms as their natural food source. We also followed the As distribution and speciation on the cuticle and within the body of G. pulex by X-ray absorption spectroscopic imaging. Half of the total As on G. pulex was found to be associated with the cuticle but was not taken up. Removing this externally bound As yielded only arsenate in the wash solution which reflects the speciation of the surrounding aquatic phase and shows that this As does not undergo any biotransformation. The major pathway into the organism is suggested to be incorporation via food intake, but only very low amounts of As were taken up or translocated from the gut system to other tissues. In one of the main food sources, leaves, 68% arsenate and 29% monomethylarsenate were found. After ingestion into the gut system, up to 23% of the more toxic arsenite was seen, but a substantial share was methylated to dimethylarsenate (46-56%). Little arsenate and arsenite were found in the adjacent tissues. Besides 76-80% mono- and di-methylarsenate, 10-21% of the As was complexed as As(III)-S species. G. pulex plays an important role in As cycling and our results indicate that As translocation from the gut to other tissues is minimized, but a transformation to other As-species occurred.

  17. Global pressures, specific responses: effects of nutrient enrichment in streams from different biomes

    NASA Astrophysics Data System (ADS)

    Artigas, Joan; García-Berthou, Emili; Bauer, Delia E.; Castro, Maria I.; Cochero, Joaquín; Colautti, Darío C.; Cortelezzi, Agustina; Donato, John C.; Elosegi, Arturo; Feijoó, Claudia; Giorgi, Adonis; Gómez, Nora; Leggieri, Leonardo; Muñoz, Isabel; Rodrigues-Capítulo, Alberto; Romaní, Anna M.; Sabater, Sergi

    2013-03-01

    We assessed the effects of nutrient enrichment on three stream ecosystems running through distinct biomes (Mediterranean, Pampean and Andean). We increased the concentrations of N and P in the stream water 1.6-4-fold following a before-after control-impact paired series (BACIPS) design in each stream, and evaluated changes in the biomass of bacteria, primary producers, invertebrates and fish in the enriched (E) versus control (C) reaches after nutrient addition through a predictive-BACIPS approach. The treatment produced variable biomass responses (2-77% of explained variance) among biological communities and streams. The greatest biomass response was observed for algae in the Andean stream (77% of the variance), although fish also showed important biomass responses (about 9-48%). The strongest biomass response to enrichment (77% in all biological compartments) was found in the Andean stream. The magnitude and seasonality of biomass responses to enrichment were highly site specific, often depending on the basal nutrient concentration and on windows of ecological opportunity (periods when environmental constraints other than nutrients do not limit biomass growth). The Pampean stream, with high basal nutrient concentrations, showed a weak response to enrichment (except for invertebrates), whereas the greater responses of Andean stream communities were presumably favored by wider windows of ecological opportunity in comparison to those from the Mediterranean stream. Despite variation among sites, enrichment globally stimulated the algal-based food webs (algae and invertebrate grazers) but not the detritus-based food webs (bacteria and invertebrate shredders). This study shows that nutrient enrichment tends to globally enhance the biomass of stream biological assemblages, but that its magnitude and extent within the food web are complex and are strongly determined by environmental factors and ecosystem structure.

  18. Variability in ecosystem structure and functioning in a low order stream: Implications of land use and season.

    PubMed

    Englert, Dominic; Zubrod, Jochen P; Schulz, Ralf; Bundschuh, Mirco

    2015-12-15

    Human activity can degrade the habitat quality for aquatic communities, which ultimately impacts the functions these communities provide. Disentangling the complex interaction between environmental and anthropogenic parameters as well as their alteration both along the stream channel, over the seasons, and finally their impact in the aquatic ecosystem represents a fundamental challenge for environmental scientists. Therefore, the present study investigates the implications of successive land uses (i.e., vineyard, urban area, highway and wastewater treatment plant (WWTP)) on structural and functional endpoints related to the ecosystem process of leaf litter breakdown during a winter and summer season in a five km stretch of a second-order stream in southern Germany. This sequence of the different land uses caused, among others, a downstream decline of the ecological status from "high" to "bad" judged based on the SPEARpesticides index together with significant shifts in the macroinvertebrate community composition, which coincided with substantial impairments (up to 100%) in the macroinvertebrate-mediated leaf decomposition. These effects, seem to be mainly driven by alterations in water quality rather than morphological modifications of the stream's habitat since the key shredder Gammarus was not in direct contact with the local habitat during in situ bioassays but showed similar response patterns than the other endpoints. While the relative effect size for most endpoints deviated considerably (sometimes above 2-fold) among seasons, the general response pattern pointed to reductions in energy supply for local and downstream communities. Although the present study focused on a single low-order stream with the main purpose of describing the impact of different land uses on various levels of biological organization, which limits the direct transferability and thus applicability of results to other stream ecosystems, the findings point to the need to develop adequate

  19. Impact of water abstraction on storage and breakdown of coarse organic matter in mountain streams.

    PubMed

    Arroita, Maite; Aristi, Ibon; Díez, Joserra; Martinez, Miren; Oyarzun, Gorka; Elosegi, Arturo

    2015-01-15

    Water abstraction is a prevalent impact in streams and rivers, which is likely to increase in the near future. Because abstraction reduces discharge, the dimensions of the wetted channel and water depth and velocity, it can have strong influence on stream ecosystem functioning. Although the impacts of large dams on stream and river ecosystems are pretty well known, the effects of diversion schemes associated with low dams are still poorly understood. Furthermore, the remote location of many diversion schemes and the lack of collaboration by power companies often make it difficult to know the volume of water diverted and its environmental consequences. To assess the impact of water abstraction on the storage and breakdown of coarse particulate organic matter in streams we compared reaches upstream and downstream from five low dams that divert water to hydropower plants in mountain streams in N Spain. We measured the storage of organic matter and the breakdown of alder leaves in winter and spring, and calculated the results at the patch (i.e., per square meter of bed) and at the reach scale (i.e., per lineal meter of channel). Water diversion significantly reduced discharge, and the width and depth of the wetted channel, but did not affect water quality. Diversion significantly reduced the storage and breakdown of organic matter in winter but not in spring. The number of shredders colonizing litter bags was also significantly reduced. The results point to an important effect of water abstraction on the storage and breakdown of organic matter in streams at least in some periods, which could affect downstream reaches, global carbon fluxes, and associated ecosystem services. PMID:25039020

  20. Incinerator performance: effects of changes in waste input and furnace operation on air emissions and residues.

    PubMed

    Astrup, Thomas; Riber, Christian; Pedersen, Anne Juul

    2011-10-01

    Waste incineration can be considered a robust technology for energy recovery from mixed waste. Modern incinerators are generally able to maintain relatively stable performance, but changes in waste input and furnace operation may affect emissions. This study investigated how inorganic air emissions and residue composition at a full-scale incinerator were affected by known additions of specific waste materials to the normal municipal solid waste (MSW) input. Six individual experiments were carried out (% ww of total waste input): NaCl (0.5%), shoes (1.6%), automobile shredder waste (14%), batteries (0.5%), poly(vinyl chloride) (5.5%) and chromate-cupper-arsenate impregnated wood (11%). Materials were selected based on chemical composition and potential for being included or excluded from the waste mix. Critical elements in the waste materials were identified based on comparison with six experiments including 'as-large-as-possible' changes in furnace operation (oxygen levels, air supply and burnout level) only using normal MSW as input. The experiments showed that effects from the added waste materials were significant in relation to: air emissions (in particular As, Cd, Cr, Hg, Sb), element transfer coefficients, and residue composition (As, Cd, Cl, Cr, Cu, Hg, Mo, Ni, Pb, S, Sb, Zn). Changes in furnace operation could not be directly linked to changes in emissions and residues. The results outlined important elements in waste which should be addressed in relation to waste incinerator performance. Likely ranges of element transfer coefficients were provided as the basis for sensitivity analysis of life-cycle assessment (LCA) results involving waste incinerator technologies. PMID:21930520

  1. The impact of cattle access on ecological water quality in streams: Examples from agricultural catchments within Ireland.

    PubMed

    Conroy, E; Turner, J N; Rymszewicz, A; O'Sullivan, J J; Bruen, M; Lawler, D; Lally, H; Kelly-Quinn, M

    2016-03-15

    Unrestricted cattle access to rivers and streams represent a potentially significant localised pressure on freshwater systems. However there is no consensus in the literature on the occurrence and extent of impact and limited research has examined the effects on aquatic biota in the humid temperate environment examined in the present study. Furthermore, this is one of the first times that research consider the potential for cattle access impacts in streams of varying water quality in Northern Europe. We investigated the effects of cattle access on macroinvertebrate communities and deposited fine sediment levels, in four rivers of high/good and four rivers of moderate water quality status which drain, low gradient, calcareous grassland catchments in Ireland. We assessed the temporal variability in macroinvertebrates communities across two seasons, spring and autumn. Site specific impacts were evident which appeared to be influenced by water quality status and season. All four high/good water status rivers revealed significant downstream changes in community structure and at least two univariate metrics (total richness and EPT richness together with taxon, E and EPT abundance). Two of the four moderate water status rivers showed significant changes in community structure, abundance and richness metrics and functional feeding groups driven in the main by downstream increases in collectors/gatherers, shredders and burrowing taxa. These two moderate water status rivers had high or prolonged livestock activity. In view of these findings, the potential for some of these sites to achieve at least high/good water quality status, as set out in the EU Water Framework Directive, may be compromised. The results presented highlight the need for additional research to further define the site specific factors and livestock management practices, under different discharge conditions, that increase the risk of impact on aquatic ecology due to these cattle-river interactions. PMID

  2. Variability in ecosystem structure and functioning in a low order stream: Implications of land use and season.

    PubMed

    Englert, Dominic; Zubrod, Jochen P; Schulz, Ralf; Bundschuh, Mirco

    2015-12-15

    Human activity can degrade the habitat quality for aquatic communities, which ultimately impacts the functions these communities provide. Disentangling the complex interaction between environmental and anthropogenic parameters as well as their alteration both along the stream channel, over the seasons, and finally their impact in the aquatic ecosystem represents a fundamental challenge for environmental scientists. Therefore, the present study investigates the implications of successive land uses (i.e., vineyard, urban area, highway and wastewater treatment plant (WWTP)) on structural and functional endpoints related to the ecosystem process of leaf litter breakdown during a winter and summer season in a five km stretch of a second-order stream in southern Germany. This sequence of the different land uses caused, among others, a downstream decline of the ecological status from "high" to "bad" judged based on the SPEARpesticides index together with significant shifts in the macroinvertebrate community composition, which coincided with substantial impairments (up to 100%) in the macroinvertebrate-mediated leaf decomposition. These effects, seem to be mainly driven by alterations in water quality rather than morphological modifications of the stream's habitat since the key shredder Gammarus was not in direct contact with the local habitat during in situ bioassays but showed similar response patterns than the other endpoints. While the relative effect size for most endpoints deviated considerably (sometimes above 2-fold) among seasons, the general response pattern pointed to reductions in energy supply for local and downstream communities. Although the present study focused on a single low-order stream with the main purpose of describing the impact of different land uses on various levels of biological organization, which limits the direct transferability and thus applicability of results to other stream ecosystems, the findings point to the need to develop adequate

  3. Development of a local-scale urban stream assessment method using benthic macroinvertebrates: An example from the Santa Clara Basin, California

    USGS Publications Warehouse

    Carter, J.L.; Purcell, A.H.; Fend, S.V.; Resh, V.H.

    2009-01-01

    Research that explores the biological response to urbanization on a site-specific scale is necessary for management of urban basins. Recent studies have proposed a method to characterize the biological response of benthic macroinvertebrates along an urban gradient for several climatic regions in the USA. Our study demonstrates how this general framework can be refined and applied on a smaller scale to an urbanized basin, the Santa Clara Basin (surrounding San Jose, California, USA). Eighty-four sampling sites on 14 streams in the Santa Clara Basin were used for assessing local stream conditions. First, an urban index composed of human population density, road density, and urban land cover was used to determine the extent of urbanization upstream from each sampling site. Second, a multimetric biological index was developed to characterize the response of macroinvertebrate assemblages along the urban gradient. The resulting biological index included metrics from 3 ecological categories: taxonomic composition ( Ephemeroptera, Plecoptera, and Trichoptera), functional feeding group (shredder richness), and habit ( clingers). The 90th-quantile regression line was used to define the best available biological conditions along the urban gradient, which we define as the predicted biological potential. This descriptor was then used to determine the relative condition of sites throughout the basin. Hierarchical partitioning of variance revealed that several site-specific variables (dissolved O2 and temperature) were significantly related to a site's deviation from its predicted biological potential. Spatial analysis of each site's deviation from its biological potential indicated geographic heterogeneity in the distribution of impaired sites. The presence and operation of local dams optimize water use, but modify natural flow regimes, which in turn influence stream habitat, dissolved O2, and temperature. Current dissolved O2 and temperature regimes deviate from natural

  4. Direct liquefaction proof-of-concept program. Finaltopical report, Bench Run 4 (227-95)

    SciTech Connect

    Comolli, A.G.; Pradhan, V.R.; Lee, T.L.K.

    1997-03-01

    This report presents the results of bench-scale work, Bench Run PB-04, conducted under the DOE Proof of Concept-Bench Option Program in direct coal liquefaction at Hydrocarbon Technologies, Inc. in Lawrenceville, New Jersey. The Bench Run PB-04 was the fifth of the nine runs planned in the POC Bench Option Contract between the U.S. DOE and Hydrocarbon Technologies, Inc. Bench Run PB-04 had multiple goals. These included the evaluation of the effects of dispersed slurry catalyst system on the performance of direct liquefaction of a subbituminous Wyoming Black Thunder mine coal under extinction recycle (454{degrees}C+ recycle) condition; another goal was to investigate the effects of the combined processing of automobile shredder residue (auto-fluff) with coal and other organic waste materials. PB-04 employed a two-stage, back-mixed, slurry reactor system with an interstage V/L separator and an in-line fixed-bed hydrotreater. The HTI`s newly modified P/Fe catalyst was very effective for direct liquefaction and coprocessing of Black Thunder mine subbituminous coal with Hondo resid and auto-fluff; during `coal-only` liquefaction mode, over 93% maf coal conversion was obtained with about 90% residuum conversion and as high as 67% light distillate (C{sub 4}-975 F) yield, while during `coprocessing` mode of operation, distillate yields varied between 58 and 69%; the residuum conversions varied between 74 and 89% maf. Overall, it is concluded, based upon the yield data available from PB-04, that auto-effective as MSW plastics in improving coal hydroconversion process performance. Auto-fluff did not increase light distillate yields nor decrease light gas make and chemical hydrogen consumption in coal liquefaction, as was observed to occur with MSW plastics.

  5. Direct liquefaction proof-of-concept program: Bench Run 05 (227-97). Final report

    SciTech Connect

    Comolli, A.G.; Pradhan, V.R.; Lee, T.L.K.; Karolkiewicz, W.F.; Popper, G.

    1997-04-01

    This report presents the results Bench Run PB-05, conducted under the DOE Proof of Concept - Bench Option Program in direct coal liquefaction at Hydrocarbon Technologies, Inc. in Lawrenceville, New Jersey. Bench Run PB-05 was the fifth of the nine runs planned in the POC Bench Option Contract between the U.S. DOE and included the evaluation of the effect of using dispersed slurry catalyst in direct liquefaction of a high volatile bituminous Illinois No. 6 coal and in combined coprocessing of coal with organic wastes, such as heavy petroleum resid, MSW plastics, and auto-shredder residue. PB-05 employed a two-stage, back-mixed, slurry reactor system with an interstage V/L separator and an in-line fixed-bed hydrotreater. Coprocessing of waste plastics with Illinois No. 6 coal did not result in the improvement observed earlier with a subbituminous coal. In particular, decreases in light gas yield and hydrogen consumption were not observed with Illinois No. 6 coal as they were with Black Thunder Mine coal. The higher thermal severity during PB-05 is a possible reason for this discrepancy, plastics being more sensitive to temperatures (cracking) than either coal or heavy resid. The ASR material was poorer than MSW plastics in terms of increasing conversions and yields. HTI`s new dispersed catalyst formulation, containing phosphorus-promoted iron gel, was highly effective for the direct liquefaction of Illinois No. 6 coal under the reaction conditions employed; over 95% coal conversion was obtained, along with over 85% residuum conversion and over 73% distillate yields.

  6. Mass balance for POPs in hazardous and municipal solid waste incinerators.

    PubMed

    Van Caneghem, J; Block, C; Van Brecht, A; Wauters, G; Vandecasteele, C

    2010-02-01

    The amount of different persistent organic pollutants (POPs) in the input of waste incinerators was compared to that in the output. Three cases were considered: a rotary kiln incinerating hazardous waste, a grate furnace incinerating municipal solid waste (MSW) and the same grate furnace co-incinerating plastics of waste of electrical and electronic equipment (WEEE) and automotive shredder residue (ASR) with MSW. The mass balance for PCBs in the rotary kiln indicates that these POPs are destroyed effectively during incineration. The grate furnace can be a sink or source of PCDD/Fs and PCBs depending on the concentrations in the incinerated waste. In order to compare the total amount of POPs in input and output, a methodology was developed whereby the amount of POPs was weighed according to minimal risk doses (MRDs) or cancer potency factors. For both incinerators the PCDD/Fs, PCBs and polyaromatic hydrocarbons (PAHs) are the main contributors to total weighed POP output. In MSW, the PCDD/Fs, PBDD/Fs and polybrominated diphenylethers (PBDEs) are the main contributors to the weighed POP input. The ratios of the weighed POP-input over -output clearly indicate that the rotary kiln incinerating hazardous waste is a weighed POP sink. The grate furnace incinerating MSW is a weighed POP sink or source depending on the POP-concentrations in the waste, but the difference between output and input is rather limited. When e.g. ASR and plastics of WEEE, containing high concentrations of PBDEs and PCBs, are co-incinerated in the grate furnace, it is clearly a weighed POP sink.

  7. On the relative importance of pool morphology and woody debris to distributions of shrimp in a Puerto Rican headwater stream

    USGS Publications Warehouse

    Pyron, M.; Covich, A.P.; Black, R.W.

    1999-01-01

    In this paper, we report the sizes and distributional orientation of woody debris in a headwater rainforest stream in the Luquillo Experimental Forest (LEF), Puerto Rico. We also provide results of a 4-month study of a wood addition experiment designed to increase cover for benthic macroinvertebrates (freshwater shrimp). We added branch-sized woody debris to 20 pools in three streams. We trapped four species of freshwater shrimp (two species of benthic detritivores and two predatory shrimp species) during each of the 4 months following wood additions. An analysis of pool morphology (maximum depth, surface area and volume) provided a useful predictor of shrimp abundances. In general, numbers of shrimps increased with sizes of stream pools. A repeated measures ANOVA demonstrated no effect of woody debris additions on total numbers of shrimp per pool area. Two detritivore species (Atya lanipes, a filter feeder and Xiphocaris elongata, a shredder) decreased in abundance with increased woody debris and there was no statistical relationship between woody debris additions and predators (Macrobrachium carcinus and M. crenulatum). Small woody debris additions may have altered flow velocities that were important to filter-feeding Atya at the microhabitat scale, although the overall velocities within pools were not altered by wood additions. Lower numbers of Atya and Xiphocaris in two of the three streams may result from the occurrence of two predaceous fishes (American eel and mountain mullet) and more predatory Macrobrachium in these streams. One likely interpretation of the results of this study is that the stream pools in these study reaches had sufficient habitat structure provided by numerous rock crevices (among large rocks and boulders) to provide refuge from predators. Addition of woody debris did not add significantly to the existing structure. These results may not apply to stream channels with sand and gravel substrata where crevices and undercut banks are lacking

  8. Riparian forest composition affects stream litter decomposition despite similar microbial and invertebrate communities.

    PubMed

    Kominoski, John S; Marczak, Laurie B; Richardson, John S

    2011-01-01

    Cross-boundary flows of energy and nutrients link biodiversity and functioning in adjacent ecosystems. The composition of forest tree species can affect the structure and functioning of stream ecosystems due to physical and chemical attributes, as well as changes in terrestrial resource subsidies. We examined how variation in riparian canopy composition (coniferous, deciduous, mixed) affects adjacent trophic levels (invertebrate and microbial consumers) and decomposition of organic matter in small, coastal rainforest streams in southwestern British Columbia. Breakdown rates of higher-quality red alder (Alnus rubra) litter were faster in streams with a greater percentage of deciduous than coniferous riparian canopy, whereas breakdown rates of lower-quality western hemlock (Tsuga heterophylla) litter were independent of riparian forest composition. When invertebrates were excluded using fine mesh, breakdown rates of both litter species were an order of magnitude less and were not significantly affected by riparian forest composition. Stream invertebrate and microbial communities were similar among riparian forest composition, with most variation attributed to leaf litter species. Invertebrate taxa richness and shredder biomass were higher in A. rubra litter; however, taxa evenness was greatest for T. heterophylla litter and both litter species in coniferous streams. Microbial community diversity (determined from terminal restriction fragment length polymorphisms) was unaffected by riparian forest or litter species. Fungal allele richness was higher than bacterial allele richness, and microbial communities associated with lower-quality T. heterophylla litter had higher diversity (allele uniqueness and richness) than those associated with higher-quality A. rubra litter. Percent variation in breakdown rates was mostly attributed to riparian forest composition in the presence of invertebrates and microbes; however, stream consumer biodiversity at adjacent trophic levels

  9. Hartree-Fock values of energies, interaction constants, and atomic properties for excited states with 3 d N4 s0 and 3 d n4 s2 configurations of the negative ions, neutral atoms, and first four positive ions of the transition elements

    NASA Astrophysics Data System (ADS)

    Snyder, C. D.; Jastram, J. D.; Hitt, N. P.; Woffod, J.; Rice, K. C.

    2012-12-01

    Global climate-change models predict warmer stream temperatures, but there have been few studies that document such effects on stream communities. In Shenandoah National Park, Virginia, long-term temperature records indicate that stream temperatures show an increasing trend over the last 20 years and especially over the last 10 years. Stream temperatures have increased apparently due to atmospheric warming (i.e., stream temperatures are strongly correlated with regional air temperature patterns). Across 14 monitored stream sites, the median increase in maximum annual water temperature was 0.32oC per year for the 10-yr period between 2000 and 2009, and all 14 sites had positive trend slopes. Moreover, in contrast to water-chemistry trends, temperature trends showed no spatial structure and were consistent throughout the park. The observed warming is consistent with global warming projections, but other factors, including the North Atlantic Oscillation and forest defoliation due to gypsy moth (Lepidoptera: Lymantriidae), also may have contributed to warming trends. We summarized benthic macroinvertebrate community composition and structure from samples collected at 24 stream sites over the last 20 years and evaluated temporal patterns in the context of observed temperature trends. We found that a substantial amount of temporal variation in both taxonomic composition and community structure could be explained by temperature trends, even after accounting for water-chemistry changes. We observed significant declines in community diversity as well as a decline in the abundance of several stonefly (Plecoptera) taxa, a cold-water-dependent taxonomic group. We hypothesize that temperature-induced changes in the diversity and composition of macroinvertebrate communities could cascade to other faunal groups and other parts of the watershed. For instance, reduced abundances of stoneflies, an important component of the shredder functional group, may lead to reduced export of

  10. Long-term impacts on macroinvertebrates downstream of reclaimed mountaintop mining valley fills in Central Appalachia.

    PubMed

    Pond, Gregory J; Passmore, Margaret E; Pointon, Nancy D; Felbinger, John K; Walker, Craig A; Krock, Kelly J G; Fulton, Jennifer B; Nash, Whitney L

    2014-10-01

    Recent studies have documented adverse effects to biological communities downstream of mountaintop coal mining and valley fills (VF), but few data exist on the longevity of these impacts. We sampled 15 headwater streams with VFs reclaimed 11-33 years prior to 2011 and sampled seven local reference sites that had no VFs. We collected chemical, habitat, and benthic macroinvertebrate data in April 2011; additional chemical samples were collected in September 2011. To assess ecological condition, we compared VF and reference abiotic and biotic data using: (1) ordination to detect multivariate differences, (2) benthic indices (a multimetric index and an observed/expected predictive model) calibrated to state reference conditions to detect impairment, and (3) correlation and regression analysis to detect relationships between biotic and abiotic data. Although VF sites had good instream habitat, nearly 90 % of these streams exhibited biological impairment. VF sites with higher index scores were co-located near unaffected tributaries; we suggest that these tributaries were sources of sensitive taxa as drifting colonists. There were clear losses of expected taxa across most VF sites and two functional feeding groups (% scrapers and %shredders) were significantly altered. Percent VF and forested area were related to biological quality but varied more than individual ions and specific conductance. Within the subset of VF sites, other descriptors (e.g., VF age, site distance from VF, the presence of impoundments, % forest) had no detectable relationships with biological condition. Although these VFs were constructed pursuant to permits and regulatory programs that have as their stated goals that (1) mined land be reclaimed and restored to its original use or a use of higher value, and (2) mining does not cause or contribute to violations of water quality standards, we found sustained ecological damage in headwaters streams draining VFs long after reclamation was completed.

  11. Long-Term Impacts on Macroinvertebrates Downstream of Reclaimed Mountaintop Mining Valley Fills in Central Appalachia

    NASA Astrophysics Data System (ADS)

    Pond, Gregory J.; Passmore, Margaret E.; Pointon, Nancy D.; Felbinger, John K.; Walker, Craig A.; Krock, Kelly J. G.; Fulton, Jennifer B.; Nash, Whitney L.

    2014-10-01

    Recent studies have documented adverse effects to biological communities downstream of mountaintop coal mining and valley fills (VF), but few data exist on the longevity of these impacts. We sampled 15 headwater streams with VFs reclaimed 11-33 years prior to 2011 and sampled seven local reference sites that had no VFs. We collected chemical, habitat, and benthic macroinvertebrate data in April 2011; additional chemical samples were collected in September 2011. To assess ecological condition, we compared VF and reference abiotic and biotic data using: (1) ordination to detect multivariate differences, (2) benthic indices (a multimetric index and an observed/expected predictive model) calibrated to state reference conditions to detect impairment, and (3) correlation and regression analysis to detect relationships between biotic and abiotic data. Although VF sites had good instream habitat, nearly 90 % of these streams exhibited biological impairment. VF sites with higher index scores were co-located near unaffected tributaries; we suggest that these tributaries were sources of sensitive taxa as drifting colonists. There were clear losses of expected taxa across most VF sites and two functional feeding groups (% scrapers and %shredders) were significantly altered. Percent VF and forested area were related to biological quality but varied more than individual ions and specific conductance. Within the subset of VF sites, other descriptors (e.g., VF age, site distance from VF, the presence of impoundments, % forest) had no detectable relationships with biological condition. Although these VFs were constructed pursuant to permits and regulatory programs that have as their stated goals that (1) mined land be reclaimed and restored to its original use or a use of higher value, and (2) mining does not cause or contribute to violations of water quality standards, we found sustained ecological damage in headwaters streams draining VFs long after reclamation was completed.

  12. Evaluating water quality impacts on macroinvertebrates below a copper-silver mine using functional feeding groups as bioindicators

    SciTech Connect

    MacLellan, D.; Volosin, J.; Cardwell, R.

    1995-12-31

    Biological monitoring of metal sensitive taxa for the past nine years from two stream systems downstream of a copper/silver mine in Montana have not disclosed any adverse impacts or degradation in either stream system. The program was designed to determine whether potential non-point sources of pollution from the mining activities were adversely affecting the health of biological communities in local streams. As an alternative method of data analysis, densities of the taxa representing six functional feeding groups of benthic macroinvertebrates (i.e., filterer-collectors, scrapers, predators, collector-gatherers, shredders, and omnivores) were evaluated for statistical differences between target and reference locations using a three-way analysis of variance (ANOVAS) using study locations, seasons, and years as factors. A non-parametric trend analysis was also performed to check for long-term trends in each system. Benthic macroinvertebrates (e.g., mayflies and stoneflies) have been collected over the past nine years during the spring, summer and fall. Samples have been collected at five locations in two stream systems and have been identified to family, genus and/or species level. Following identification, taxa were assigned to the appropriate functional feeding group. In both systems, the dominant feeding group was collector-gathers, followed by predators. The ANOVAs did not reveal consistent significant differences between reference and target locations. Therefore, differences in functional feeding group densities appear to have been random or attributable to long-term habitat changes. Long-term trends were observed in taxa representing different feeding groups, with some increasing and some decreasing over the 9-year life of the monitoring program.

  13. Habitat Restoration and Monitoring in Urban Streams: The Case of Tryon Creek in Portland, OR

    NASA Astrophysics Data System (ADS)

    Rios Touma, B. P.; Prescott, C.; Axtell, S.; Kondolf, G. M.

    2013-12-01

    Habitat enhancement in urban streams can be important for threatened species but challenging, because of altered catchment hydrology and urban encroachment on floodplains and channel banks. In Portland (OR) restoration actions have been undertaken at the watershed scale (e.g.: storm water management, protection of sites with high watershed value) to improve water quality, and at reach scale, when water quality and quantity are adequate, to increase habitat heterogeneity and stabilize banks. To evaluate reach-scale restoration projects in the Tryon Creek watershed, we sampled benthic macroinvertebrates and conducted habitat quality surveys pre-project and over 4 years post- project. Species sensitive to pollution and diversity of trophic groups increased after restoration. Although taxonomical diversity increased after restoration, but was still low compared to reference streams. We found no significant changes in trait proportions and functional diversity. Functional diversity, proportion of shredders and semivoltine invertebrates were significantly higher in reference streams than the restored stream reaches. We hypothesized that inputs of coarse particulate organic matter and land use at watershed scale may explain the differences in biodiversity between restored and reference stream reaches. Variables such as substrate composition, canopy cover or large wood pieces did not change from pre- to post-project, so could not explain the changes in the community. This may have been partly attributable to insensitivity of the visual estimate methods used, but likely also reflects an importance influence of watershed variables on aquatic biota - suggesting watershed actions may be more effective for the ecological recovery of streams. For future projects, we recommend multihabitat benthic sampling supported by studies of channel geomorphology to better understand stream response to restoration actions.

  14. Use of leaf litter breakdown and macroinvertebrates to evaluate gradient of recovery in an acid mine impacted stream remediated with an active alkaline doser.

    PubMed

    Johnson, Kelly S; Thompson, Peter C; Gromen, Lori; Bowman, Jen

    2014-07-01

    The spatial congruence of chemical and biological recovery along an 18-km acid mine impaired stream was examined to evaluate the efficacy of treatment with an alkaline doser. Two methods were used to evaluate biological recovery: the biological structure of the benthic macroinvertebrate community and several ecosystem processing measures (leaf litter breakdown, microbial respiration rates) along the gradient of improved water chemistry. We found that the doser successfully reduced the acidity and lowered dissolved metals (Al, Fe, and Mn), but downstream improvements were not linear. Water chemistry was more variable, and precipitated metals were elevated in a 3-5-km "mixing zone" immediately downstream of the doser, then stabilized into a "recovery zone" 10-18 km below the doser. Macroinvertebrate communities exhibited a longitudinal pattern of recovery, but it did not exactly match the water chemistry gradient Taxonomic richness (number of families) recovered about 6.5 km downstream of the doser, while total abundance and % EPT taxa recovery were incomplete except at the most downstream site, 18 km away. The functional measures of ecosystem processes (leaf litter breakdown, microbial respiration of conditioned leaves, and shredder biomass) closely matched the measures of community structure and also showed a more modest longitudinal trend of biological recovery than expected based on pH and alkalinity. The measures of microbial respiration had added diagnostic value and indicated that biological recovery downstream of the doser is limited by factors other than habitat and acidity/alkalinity, perhaps episodes of AMD and/or impaired energy/nutrient inputs. A better understanding of the factors that govern spatial and temporal variations in acid mine contaminants, especially episodic events, will improve our ability to predict biological recovery after remediation.

  15. Metal/metalloid accumulation/remobilization during aquatic litter decomposition in freshwater: a review.

    PubMed

    Schaller, Jörg; Brackhage, Carsten; Mkandawire, Martin; Dudel, E Gert

    2011-11-01

    The focus of this article is to combine two main areas of research activities in freshwater ecosystems: the effect of inorganic pollutants on freshwater ecosystems and litter decomposition as a fundamental ecological process in streams. The decomposition of plant litter in aquatic systems as a main energy source in running water ecosystems proceeds in three distinct temporal stages of leaching, conditioning and fragmentation. During these stages metals and metalloids may be fixed by litter, its decay products and the associated organisms. The global-scale problem of contaminated freshwater ecosystems by metals and metalloids has led to many investigations on the acute and chronic toxicity of these elements to plants and animals as well as the impact on animal activity under laboratory conditions. Where sorption properties and accumulation/remobilization potential of metals in sediments and attached microorganisms are quite well understood, the combination of both research areas concerning the impact of higher trophic levels on the modification of sediment sorption conditions and the influence of metal/metalloid pollution on decomposition of plant litter mediated by decomposer community, as well as the effect of high metal load during litter decay on organism health under field conditions, has still to be elucidated. So far it was found that microbes and invertebrate shredder (species of the genera Gammarus and Asellus) have a significant influence on metal fixation on litter. Not many studies focus on the impact of other functional groups affecting litter decay (e.g. grazer and collectors) or other main processes in freshwater ecosystems like bioturbation (e.g. Tubifex, Chironomus) on metal fixation/release. PMID:21907393

  16. Long-term impacts on macroinvertebrates downstream of reclaimed mountaintop mining valley fills in Central Appalachia.

    PubMed

    Pond, Gregory J; Passmore, Margaret E; Pointon, Nancy D; Felbinger, John K; Walker, Craig A; Krock, Kelly J G; Fulton, Jennifer B; Nash, Whitney L

    2014-10-01

    Recent studies have documented adverse effects to biological communities downstream of mountaintop coal mining and valley fills (VF), but few data exist on the longevity of these impacts. We sampled 15 headwater streams with VFs reclaimed 11-33 years prior to 2011 and sampled seven local reference sites that had no VFs. We collected chemical, habitat, and benthic macroinvertebrate data in April 2011; additional chemical samples were collected in September 2011. To assess ecological condition, we compared VF and reference abiotic and biotic data using: (1) ordination to detect multivariate differences, (2) benthic indices (a multimetric index and an observed/expected predictive model) calibrated to state reference conditions to detect impairment, and (3) correlation and regression analysis to detect relationships between biotic and abiotic data. Although VF sites had good instream habitat, nearly 90 % of these streams exhibited biological impairment. VF sites with higher index scores were co-located near unaffected tributaries; we suggest that these tributaries were sources of sensitive taxa as drifting colonists. There were clear losses of expected taxa across most VF sites and two functional feeding groups (% scrapers and %shredders) were significantly altered. Percent VF and forested area were related to biological quality but varied more than individual ions and specific conductance. Within the subset of VF sites, other descriptors (e.g., VF age, site distance from VF, the presence of impoundments, % forest) had no detectable relationships with biological condition. Although these VFs were constructed pursuant to permits and regulatory programs that have as their stated goals that (1) mined land be reclaimed and restored to its original use or a use of higher value, and (2) mining does not cause or contribute to violations of water quality standards, we found sustained ecological damage in headwaters streams draining VFs long after reclamation was completed

  17. Leaf breakdown in streams differing in catchment land use

    USGS Publications Warehouse

    Paul, M.J.; Meyer, J.L.; Couch, C.A.

    2006-01-01

    1. The impact of changes in land use on stream ecosystem function is poorly understood. We studied leaf breakdown, a fundamental process of stream ecosystems, in streams that represent a range of catchment land use in the Piedmont physiographic province of the south-eastern United States. 2. We placed bags of chalk maple (Acer barbatum) leaves in similar-sized streams in 12 catchments of differing dominant land use: four forested, three agricultural, two suburban and three urban catchments. We measured leaf mass, invertebrate abundance and fungal biomass in leaf bags over time. 3. Leaves decayed significantly faster in agricultural (0.0465 day-1) and urban (0.0474 day-1) streams than in suburban (0.0173 day-1) and forested (0.0100 day-1) streams. Additionally, breakdown rates in the agricultural and urban streams were among the fastest reported for deciduous leaves in any stream. Nutrient concentrations in agricultural streams were significantly higher than in any other land-use type. Fungal biomass associated with leaves was significantly lower in urban streams; while shredder abundance in leaf bags was significantly higher in forested and agricultural streams than in suburban and urban streams. Storm runoff was significantly higher in urban and suburban catchments that had higher impervious surface cover than forested or agricultural catchments. 4. We propose that processes accelerating leaf breakdown in agricultural and urban streams were not the same: faster breakdown in agricultural streams was due to increased biological activity as a result of nutrient enrichment, whereas faster breakdown in urban streams was a result of physical fragmentation resulting from higher storm runoff. ?? 2006 The Authors.

  18. Leaf litter decomposition of native and introduced tree species of contrasting quality in headwater streams: how does the regional setting matter?

    PubMed

    Casas, J Jesús; Larrañaga, Aitor; Menéndez, Margarita; Pozo, Jesús; Basaguren, Ana; Martínez, Aingeru; Pérez, Javier; González, José M; Mollá, Salvador; Casado, Carmen; Descals, Enrique; Roblas, Neftalí; López-González, J Antonio; Valenzuela, J Luis

    2013-08-01

    Terrestrial plant litter is important in sustaining stream food webs in forested headwaters. Leaf litter quality often decreases when native species are replaced by introduced species, and a lower quality of leaf litter inputs may alter litter decomposition at sites afforested with non-native species. However, since detritivore composition and resource use plasticity may depend on the prevalent litter inputs, the extent of the alteration in decomposition can vary between streams. We tested 2 hypotheses using 2 native and 3 introduced species of tree differing in quality in 4 Iberian regions with contrasting vegetational traits: 1) decomposition rates of all plant species would be higher in regions where streams normally receive litter inputs of lower rather than higher quality; 2) a higher resource-use plasticity of detritivores in regions vegetated with plants of lower litter quality will cause a greater evenness in decomposition rates among plant species compared to regions where streams normally receive higher-quality plant litter inputs. Results showed a highly consistent interspecific ranking of decomposition rates across regions driven by litter quality, and a significant regional effect. Hypothesis 1 was supported: decomposition rates of the five litter types were generally higher in streams from regions vegetated with species producing leaf litter of low quality, possibly due to the profusion of caddisfly shredders in their communities. Hypothesis 2 was not supported: the relative differences in decomposition rates among leaf litter species remained essentially unaltered across regions. Our results suggest that, even in regions where detritivores can be comparatively efficient using resources of low quality, caution is needed particularly when afforestation programs introduce plant species of lower litter quality than the native species.

  19. Impact of water abstraction on storage and breakdown of coarse organic matter in mountain streams.

    PubMed

    Arroita, Maite; Aristi, Ibon; Díez, Joserra; Martinez, Miren; Oyarzun, Gorka; Elosegi, Arturo

    2015-01-15

    Water abstraction is a prevalent impact in streams and rivers, which is likely to increase in the near future. Because abstraction reduces discharge, the dimensions of the wetted channel and water depth and velocity, it can have strong influence on stream ecosystem functioning. Although the impacts of large dams on stream and river ecosystems are pretty well known, the effects of diversion schemes associated with low dams are still poorly understood. Furthermore, the remote location of many diversion schemes and the lack of collaboration by power companies often make it difficult to know the volume of water diverted and its environmental consequences. To assess the impact of water abstraction on the storage and breakdown of coarse particulate organic matter in streams we compared reaches upstream and downstream from five low dams that divert water to hydropower plants in mountain streams in N Spain. We measured the storage of organic matter and the breakdown of alder leaves in winter and spring, and calculated the results at the patch (i.e., per square meter of bed) and at the reach scale (i.e., per lineal meter of channel). Water diversion significantly reduced discharge, and the width and depth of the wetted channel, but did not affect water quality. Diversion significantly reduced the storage and breakdown of organic matter in winter but not in spring. The number of shredders colonizing litter bags was also significantly reduced. The results point to an important effect of water abstraction on the storage and breakdown of organic matter in streams at least in some periods, which could affect downstream reaches, global carbon fluxes, and associated ecosystem services.

  20. Hydrological cycle effects on the aquatic community in a Neotropical stream of the Andean piedmont during the 2007-2010 ENSO events.

    PubMed

    Ríos-Pulgarín, M I; Barletta, M; Mancera-Rodriguez, N J

    2016-07-01

    shredder and collector-gatherer macroinvertebrates was observed. Differentiated responses recorded in the community were based on adaptive strategies for the local hydrological regime that enable fast recovery under conditions such as ENSO phenomena. Composition changes according to adaptations to different hydrological scenarios and the predominance of generalists' trophic guilds and species with plasticity in their habits and their ranges of environmental tolerance were found, supporting the habitat templet model. PMID:26864787

  1. The Design and Construction of the Advanced Mixed Waste Treatment Facility

    SciTech Connect

    Harrop, G.

    2003-02-27

    The Advanced Mixed Treatment Project (AMWTP) privatized contract was awarded to BNFL Inc. in December 1996 and construction of the main facility commenced in August 2000. The purpose of the advanced mixed waste treatment facility is to safely treat plutonium contaminated waste, currently stored in drums and boxes, for final disposal at the Waste Isolation Pilot Plant (WIPP). The plant is being built at the Idaho National Engineering and Environmental Laboratory. Construction was completed in 28 months, to satisfy the Settlement Agreement milestone of December 2002. Commissioning of the related retrieval and characterization facilities is currently underway. The first shipment of pre-characterized waste is scheduled for March 2003, with AMWTP characterized and certified waste shipments from June 2003. To accommodate these challenging delivery targets BNFL adopted a systematic and focused construction program that included the use of a temporary structure to allow winter working, proven design and engineering principles and international procurement policies to help achieve quality and schedule. The technology involved in achieving the AMWTP functional requirements is primarily based upon a BNFL established pedigree of plant and equipment; applied in a manner that suits the process and waste. This technology includes the use of remotely controlled floor mounted and overhead power manipulators, a high power shredder and a 2000-ton force supercompactor with the attendant glove box suite, interconnections and automated material handling. The characterization equipment includes real-time radiography (RTR) units, drum and box assay measurement systems, drum head space gas sampling / analysis and drum venting, drum coring and sampling capabilities. The project adopted a particularly stringent and intensive pre-installation testing philosophy to ensure that equipment would work safely and reliably at the required throughput. This testing included the complete off site

  2. The presence and leachability of antimony in different wastes and waste handling facilities in Norway.

    PubMed

    Okkenhaug, G; Almås, Å R; Morin, N; Hale, S E; Arp, H P H

    2015-11-01

    well as from the vent of WEEE sorting facility. The WEEE vent had the highest Sb concentration (from <100 to 2200 ng m(-3)), which were orders of magnitude higher than the air surrounding the combustible shredder (from 25 to 217 ng m(-3)), and the incinerator chimney (from <30 to 100 ng m(-3)). From these results, it seems evident that Sb from waste is not an environmental concern in Norway, and that Sb is mostly readily recovered from plastic and bottom ash.

  3. Macroinvertebrate Community Structure Along the Longitudinal Gradient of an Agriculturally Impacted Stream

    PubMed

    Delong; Brusven

    1998-05-01

    / Lapwai Creek, an agriculturally impacted stream in northern Idaho, was sampled seasonally over a two-year period to determine if macroinvertebrate community composition changed along the longitudinal gradient and if changes followed predictions of the river continuum concept. Possible relationships between changes in food resource availability and community structure were also examined. Benthic invertebrates were collected at eight locations along the longitudinal gradient of Lapwai Creek using a Hess sampler. Random skewer analysis suggested there was no longitudinal gradient for either number of individuals or functional feeding group composition. Cluster analysis revealed that all locations, excluding a site receiving outflow from a small, eutrophic reservoir, had a similar community structure, further suggesting that invertebrate community composition remained consistent along the longitudinal gradient of the stream. The community was dominated at all sites, excluding the site below the reservoir, by functionalgrazers. Shredders were rare throughout Lapwai Creek, even in areas where healthy riparian vegetation still remained. Studies of other streams within the drainage basin show that many species found in the upper reaches of these streams, where agricultural impacts are low, were absent throughout the length of Lapwai Creek. Data collected concurrently with macroinvertebrates indicated that the input, storage, and transport of particulate organic matter was low throughout the stream, whereas periphyton abundance was high. The absence of longitudinal changes, despite flowing through three distinct geomorphological regions, and the grouping of all sites except one by cluster analysis for both dominant taxa and functional feeding groups suggest that agricultural alteration has influenced community structure of Lapwai Creek, resulting in a relatively homogeneous assemblage of macroinvertebrates capable of tolerating agricultural nonpoint source pollution

  4. Thermal process of fluff: preliminary tests on a full-scale treatment plant.

    PubMed

    Mancini, G; Tamma, R; Viotti, P

    2010-01-01

    Until only recently fluff has been largely disposed of in controlled landfill sites. However, in Europe environmental regulations, including the EU Landfill Directive 1999/31/EC and ELV (End of Life Vehicle) Directive 2000/53/EC, have dramatically increased the pressure on all stakeholders to develop alternative solutions. As increasingly stringent legislation forces Shredder Residues (SR) to be diverted from landfilling, newly developed technologies will be in a position to compete for the market value of disposing of the waste. However, the fluff waste stream is so variable that it cannot be automatically assumed that processes developed for one type of fluff will prove to be suitable for other fluff streams. This situation has contributed towards convincing stakeholders to withhold investment funds or delay taking decisions as to how best to proceed; as a consequence, very few technologies have been fully developed on a commercial basis. It is of particular interest therefore that commercial alternatives to be used in dealing with this complex waste stream should be identified. The present paper illustrates the findings of a full-scale thermal treatment performed on SR samples obtained from various shredding plants. The outcome of the study provides an important contribution towards assessing the feasibility and reliability of the process, thus constituting a basic prerequisite for process performance evaluation. The full-scale plant, designed for the thermo-valorization of tyres, was purpose-modified to allow for fluff combustion. Three different fluff compositions (car fluff with different percentage of shredding, whites and 100% car fluff) were taken into consideration. Both the raw samples and solid products were thoroughly characterized. Combustion emissions were continuously analyzed during the test period, alternatively operating for tyre and fluff combustion. Classification of combustion residues for landfill disposal was carried out indicating only 2

  5. Trophic analysis of three species of Marilia (Trichoptera: Odontoceridae) from the neotropics.

    PubMed

    Reynaga, María Celina; Rueda Martín, Paola Alejandra

    2014-06-01

    primarily assigned to the functional group of shredders and secondarily to the collector-gatherer class. They inhabit sandy bottoms of mountain streams, have strong scoop-shaped mouthparts and show a diet dominated by leaf litter and fine particulate material. We concluded that the functional group assignment to the genus level for Marilia is not recommended, and further studies at species level are necessary.

  6. Effects of Debris Flows on Stream Ecosystems of the Klamath Mountains, Northern California

    NASA Astrophysics Data System (ADS)

    Cover, M. R.; Delafuente, J. A.; Resh, V. H.

    2006-12-01

    We examined the long-term effects of debris flows on channel characteristics and aquatic food webs in steep (0.04-0.06 slope), small (4-6 m wide) streams. A large rain-on-snow storm event in January 1997 resulted in numerous landslides and debris flows throughout many basins in the Klamath Mountains of northern California. Debris floods resulted in extensive impacts throughout entire drainage networks, including mobilization of valley floor deposits and removal of vegetation. Comparing 5 streams scoured by debris flows in 1997 and 5 streams that had not been scoured as recently, we determined that debris-flows decreased channel complexity by reducing alluvial step frequency and large woody debris volumes. Unscoured streams had more diverse riparian vegetation, whereas scoured streams were dominated by dense, even-aged stands of white alder (Alnus rhombiflia). Benthic invertebrate shredders, especially nemourid and peltoperlid stoneflies, were more abundant and diverse in unscoured streams, reflecting the more diverse allochthonous resources. Debris flows resulted in increased variability in canopy cover, depending on degree of alder recolonization. Periphyton biomass was higher in unscoured streams, but primary production was greater in the recently scoured streams, suggesting that invertebrate grazers kept algal assemblages in an early successional state. Glossosomatid caddisflies were predominant scrapers in scoured streams; heptageniid mayflies were abundant in unscoured streams. Rainbow trout (Oncorhynchus mykiss) were of similar abundance in scoured and unscoured streams, but scoured streams were dominated by young-of-the-year fish while older juveniles were more abundant in unscoured streams. Differences in the presence of cold-water (Doroneuria) versus warm-water (Calineuria) perlid stoneflies suggest that debris flows have altered stream temperatures. Debris flows have long-lasting impacts on stream communities, primarily through the cascading effects of

  7. Functional feeding groups of aquatic insect families in Latin America: a critical analysis and review of existing literature.

    PubMed

    Ramírez, Alonso; Gutiérrez-Fonseca, Pablo E

    2014-04-01

    Aquatic macroinvertebrates are involved in numerous processes within aquatic ecosystems. They often have important effects on ecosystem processes such as primary production (via grazing), detritus breakdown, and nutrient mineralization and downstream spiraling. The functional feeding groups (FFG) classification was developed as a tool to facilitate the incorporation of macroinvertebrates in studies of aquatic ecosystems. This classification has the advantage of combining morphological characteristics (e.g., mouth part specialization) and behavioral mechanisms (e.g., way of feeding) used by macroinvertebrates when consuming resources. Although recent efforts have greatly advanced our ability to identify aquatic macroinvertebrates, there is limited information on FFG assignment. Furthermore, there has been some variation in the use of the FFG classification, in part due to an emphasis on using gut content analysis to assign FFG, which is more appropriate for assigning trophic guilds. Thus, the main goals of this study are to (1) provide an overview of the value of using the FFG classification, (2) make an initial attempt to summarize available information on FFG for aquatic insects in Latin America, and (3) provide general guidelines on how to assign organisms to their FFGs. FFGs are intended to reflect the potential effects of organisms in their ecosystems and the way they consume resources. Groups include scrapers that consume resources that grow attached to the substrate by removing them with their mouth parts; shredders that cut or chew pieces of living or dead plant material, including all plant parts like leaves and wood; collectors-gatherers that use modified mouth parts to sieve or collect small particles (< 1 mm) accumulated on the stream bottom; filterers that have special adaptations to remove particles directly from the water column; and predators that consume other organisms using different strategies to capture them. In addition, we provide details on

  8. Influence of dietary carbon on mercury bioaccumulation in streams of the Adirondack Mountains of New York and the Coastal Plain of South Carolina, USA

    USGS Publications Warehouse

    Riva-Murray, Karen; Bradley, Paul M.; Chasar, Lia C.; Button, Daniel T.; Brigham, Mark E.; Eikenberry, Barbara C. Scudder; Journey, Celeste A.; Lutz, Michelle A.

    2013-01-01

    We studied lower food webs in streams of two mercury-sensitive regions to determine whether variations in consumer foraging strategy and resultant dietary carbon signatures accounted for observed within-site and among-site variations in consumer mercury concentration. We collected macroinvertebrates (primary consumers and predators) and selected forage fishes from three sites in the Adirondack Mountains of New York, and three sites in the Coastal Plain of South Carolina, for analysis of mercury (Hg) and stable isotopes of carbon (δ13C) and nitrogen (δ15N). Among primary consumers, scrapers and filterers had higher MeHg and more depleted δ13C than shredders from the same site. Variation in δ13C accounted for up to 34 % of within-site variation in MeHg among primary consumers, beyond that explained by δ15N, an indicator of trophic position. Consumer δ13C accounted for 10 % of the variation in Hg among predatory macroinvertebrates and forage fishes across these six sites, after accounting for environmental aqueous methylmercury (MeHg, 5 % of variation) and base-N adjusted consumer trophic position (Δδ15N, 22 % of variation). The δ13C spatial pattern within consumer taxa groups corresponded to differences in benthic habitat shading among sites. Consumers from relatively more-shaded sites had more enriched δ13C that was more similar to typical detrital δ13C, while those from the relatively more-open sites had more depleted δ13C. Although we could not clearly attribute these differences strictly to differences in assimilation of carbon from terrestrial or in-channel sources, greater potential for benthic primary production at more open sites might play a role. We found significant variation among consumers within and among sites in carbon source; this may be related to within-site differences in diet and foraging habitat, and to among-site differences in environmental conditions that influence primary production. These observations suggest that different

  9. Functional feeding groups of aquatic insect families in Latin America: a critical analysis and review of existing literature.

    PubMed

    Ramírez, Alonso; Gutiérrez-Fonseca, Pablo E

    2014-04-01

    Aquatic macroinvertebrates are involved in numerous processes within aquatic ecosystems. They often have important effects on ecosystem processes such as primary production (via grazing), detritus breakdown, and nutrient mineralization and downstream spiraling. The functional feeding groups (FFG) classification was developed as a tool to facilitate the incorporation of macroinvertebrates in studies of aquatic ecosystems. This classification has the advantage of combining morphological characteristics (e.g., mouth part specialization) and behavioral mechanisms (e.g., way of feeding) used by macroinvertebrates when consuming resources. Although recent efforts have greatly advanced our ability to identify aquatic macroinvertebrates, there is limited information on FFG assignment. Furthermore, there has been some variation in the use of the FFG classification, in part due to an emphasis on using gut content analysis to assign FFG, which is more appropriate for assigning trophic guilds. Thus, the main goals of this study are to (1) provide an overview of the value of using the FFG classification, (2) make an initial attempt to summarize available information on FFG for aquatic insects in Latin America, and (3) provide general guidelines on how to assign organisms to their FFGs. FFGs are intended to reflect the potential effects of organisms in their ecosystems and the way they consume resources. Groups include scrapers that consume resources that grow attached to the substrate by removing them with their mouth parts; shredders that cut or chew pieces of living or dead plant material, including all plant parts like leaves and wood; collectors-gatherers that use modified mouth parts to sieve or collect small particles (< 1 mm) accumulated on the stream bottom; filterers that have special adaptations to remove particles directly from the water column; and predators that consume other organisms using different strategies to capture them. In addition, we provide details on

  10. Critical working tasks and determinants of exposure to bioaerosols and MVOC at composting facilities.

    PubMed

    Persoons, Renaud; Parat, Sylvie; Stoklov, Muriel; Perdrix, Alain; Maitre, Anne

    2010-09-01

    Airborne bioaerosols and Microbial Volatile Organic Compounds (MVOC) concentrations were simultaneously monitored at a composting facility and the main determinants of atmospheric concentrations were characterised, in order to help protect workers from potential adverse health effects. Microorganisms and MVOC were sampled during various process stages and working tasks, both on site at the two units (green waste and biowaste), and at the border of the composting facility. Ambient monitorings were performed at sampling points deemed representative of occupational exposures for critical working tasks, and additional individual samplings were done on workers for MVOC. A linear regression model was used to estimate the determinants explaining exposure variability to bioaerosols and volatile compounds. Bioaerosol concentrations ranging from 10(2) to 1.8x10(5)cfu/m(3) were observed, with peak exposures in the shredding and waste sieving phases. Shredder and siever adjustments, cleaning and maintenance of aeration systems/composting containers were associated with the highest bioaerosols ambient concentrations. MVOC concentration profiles were highly variable depending on the composting unit. Shredding/rotting phases were associated with the highest levels at respectively green waste/biowaste units. Terpenoids and alcohols were the most predominant compounds, and total MVOC levels reached up to 40mg/m(3). Individual and ambient MVOC concentrations did not show significant differences. "Season", "waste turning", "process stage" and "sampling location" were the main determinants of bioaerosols and MVOC concentrations variability. Moderate or no correlation was found between microorganisms and volatile organic compounds concentrations. The high bioaerosol and MVOC levels observed as well as the potential of additive irritative effects resulting from these exposures justify the wearing of personal protective equipments for the associated working tasks. On the other hand, low

  11. The presence and leachability of antimony in different wastes and waste handling facilities in Norway.

    PubMed

    Okkenhaug, G; Almås, Å R; Morin, N; Hale, S E; Arp, H P H

    2015-11-01

    well as from the vent of WEEE sorting facility. The WEEE vent had the highest Sb concentration (from <100 to 2200 ng m(-3)), which were orders of magnitude higher than the air surrounding the combustible shredder (from 25 to 217 ng m(-3)), and the incinerator chimney (from <30 to 100 ng m(-3)). From these results, it seems evident that Sb from waste is not an environmental concern in Norway, and that Sb is mostly readily recovered from plastic and bottom ash. PMID:26449571

  12. Characterization of water quality and biological communities, Fish Creek, Teton County, Wyoming, 2007-2011

    USGS Publications Warehouse

    Eddy-Miller, Cheryl A.; Peterson, David A.; Wheeler, Jerrod D.; Edmiston, C. Scott; Taylor, Michelle L.; Leemon, Daniel J.

    2013-01-01

    relative abundance of Ephemeroptera, Plecoptera, and Trichoptera, which tend to be intolerant of water-quality degradation, decreased from April/May to August; the same time period saw a corresponding increase in Diptera and noninsects, particularly Oligochaeta (worms) that are more tolerant. Seasonal changes in macroinvertebrate functional feeding groups were significantly different. The relative abundance of gatherer-collector and scraper feeding groups decreased from April/May to August, accompanied by an increase in filterer-collector and shredders feeding groups. Seasonal changes in feeding groups might be due to the seasonal shift in aquatic plant communities, as indicated by comparison with other streams in the area that had fewer aquatic macrophytes than Fish Creek. Statistical tests of macroinvertebrate metrics indicated few differences between years or biological sampling sites on Fish Creek, although the site farthest upstream sometimes was different not only in terms of macroinvertebrates but also in streamflow, water quality, and aquatic plants. Potential effects of contributions of additional nutrients to the Fish Creek ecosystem beyond the conditions sampled during the study period are not known. However, because virtually all of the detectable dissolved nitrate commonly was consumed by aquatic plants in August (leaving dissolved nitrate less than the reporting level in water samples), it is possible that increased nutrient contributions could cause increased growth of aquatic plants. Additional long-term monitoring of the stream, with concurrent data analysis and interpretation would be needed to determine the effects of additional nutrients on the aquatic plant community and on higher levels of the food chain.