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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. Chemical and mechanical recycling of shredder fluff

    SciTech Connect

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

    1992-12-01

    Each year, the secondary metals industry recovers about 55--60 million tons of prompt and obsolete scrap which is used in the production of finished steel products. The single largest source of this scrap is the obsolete automobile. The shredder industry recovers about 10--12 million ton/yr of ferrous scrap, most of which is from shredded automobiles. However, for each ton of steel recovered, over 500 lb of fluff are produced. Shredder fluff is comprised of the nonmetallic content of the automobile and other shredded materials, such as refrigerators, dryers, and dishwashers, which are commonly called white goods. The plastics content of shredder fluff is typically about 15--20% by weight and is expected to increase over the next decade due to the significant increase in the use of automotive plastics over the past 10--15 years. At present, shredder fluff is landfilled. The rapidly escalating landfilling cost, along with environmental concerns over the fate of this waste, poses a significant cost and liability to the shredder industry. Research is being carried out to identify and develop recycling technologies that will reduce the volume and the mass of shredder fluff going to landfills and to minimize its cost impact on the recycling of secondary metals. Previous research has focused on exploiting the plastics content of shredder fluff and other hydrocarbons present in fluff for secondary recycling (e.g., production of wood-products substitutes) and for quaternary recycling (e.g., energy generation). Limited work was also conducted on tertiary recycling (e.g., pyrolysis and gasification). Although the previous research has established the technical feasibility of most, if not all, of the alternatives that were examined, none have proven to be cost-effective. This paper describes some research at Argonne National Laboratory (ANL) to develop a process to recycle some of the fluff content, primarily the thermoplastics.

  5. Chemical and mechanical recycling of shredder fluff

    SciTech Connect

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

    1992-01-01

    Each year, the secondary metals industry recovers about 55--60 million tons of prompt and obsolete scrap which is used in the production of finished steel products. The single largest source of this scrap is the obsolete automobile. The shredder industry recovers about 10--12 million ton/yr of ferrous scrap, most of which is from shredded automobiles. However, for each ton of steel recovered, over 500 lb of fluff are produced. Shredder fluff is comprised of the nonmetallic content of the automobile and other shredded materials, such as refrigerators, dryers, and dishwashers, which are commonly called white goods. The plastics content of shredder fluff is typically about 15--20% by weight and is expected to increase over the next decade due to the significant increase in the use of automotive plastics over the past 10--15 years. At present, shredder fluff is landfilled. The rapidly escalating landfilling cost, along with environmental concerns over the fate of this waste, poses a significant cost and liability to the shredder industry. Research is being carried out to identify and develop recycling technologies that will reduce the volume and the mass of shredder fluff going to landfills and to minimize its cost impact on the recycling of secondary metals. Previous research has focused on exploiting the plastics content of shredder fluff and other hydrocarbons present in fluff for secondary recycling (e.g., production of wood-products substitutes) and for quaternary recycling (e.g., energy generation). Limited work was also conducted on tertiary recycling (e.g., pyrolysis and gasification). Although the previous research has established the technical feasibility of most, if not all, of the alternatives that were examined, none have proven to be cost-effective. This paper describes some research at Argonne National Laboratory (ANL) to develop a process to recycle some of the fluff content, primarily the thermoplastics.

  6. 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... plastic separated from shredder residue under the conditions described in the Voluntary Procedures for Recycling Plastics from Shredder Residue, relying principally on the regulatory provisions for excluded...

  7. 77 FR 76518 - Certain Paper Shredders, Certain Processes for Manufacturing or Relating to Same and Certain...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-28

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

  8. 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

  9. Automobile shredder residue: Process developments for recovery of recyclable constituents

    SciTech Connect

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

    1990-01-01

    The objectives of this paper are threefold: (1) to briefly outline the structure of the automobile shredder industry as a supplier of ferrous scrap, (2) to review the previous research that has been conducted for recycling automobile shredder residue (ASR), and (3) to present the results and implications of the research being conducted at ANL on the development of a process for the selective recovery and recycling of the thermoplastics content of ASR. 15 refs., 5 figs.

  10. 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.

  11. Recovery of recyclable materials from shredder residue

    SciTech Connect

    Jody, B.J.; Daniels, E.J.; Bonsignore, P.V.; Brockmeier, N.F.

    1994-01-01

    Each year, about 11 million tons of metals (ferrous and nonferrous) are recovered in the US from about 10 million discarded automobiles. The recovered metals account for about 75% of the total weight of the discarded vehicles. The balance of the material or shredder residue, which amounts to about 3 million tons annually, is currently landfilled. The residue contains a diversity of potentially recyclable materials, including polyurethane foams, iron oxides, and certain thermoplastics. This paper 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. Status of the technology is discussed and process economics reviewed.

  12. Mass balance and composition analysis of shredder residue.

    SciTech Connect

    Pomykala, J. A., Jr.; Jody, B. J.; Spangenberger, J. S.; Daniels, E. J.; Energy Systems

    2007-01-01

    The process of shredding end-of-life vehicles to recover metals results in a byproduct commonly referred to as shredder residue. The four-and-a-half million metric tons of shredder residue produced annually in the United States is presently land filled. To meet the challenges of automotive materials recycling, the U.S. Department of Energy is supporting research at Argonne National Laboratory in cooperation with the Vehicle Recycling Partnership (VRP) of the United States Council for Automotive Research (USCAR) and the American Plastics Council. This paper presents the results of a study that was conducted by Argonne to determine variations in the composition of shredder residue from different shredders. Over 90 metric tons of shredder residues were processed through the Argonne pilot plant. The contents of the various separated streams were quantitatively analyzed to determine their composition and to identify materials that should be targeted for recovery. The analysis established a reliable mass balance for the different materials in shredder residue.

  13. 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...

  14. Preparation of industrial solid waste into boiler fuel with a single horizontal shredder

    SciTech Connect

    Matthews, W.R.

    1982-01-01

    The paper describes a horizontal shredder, complete with an infeed and outfeed system that was placed in service at the Kodak Park solid waste disposal facility in Rochester, New York. This shredder has become the primary shredder for preparing solid waste for incineration in a suspension-fired boiler. Before discussing the details of this shredder installation, a brief review of the operating problems and modifications which have evolved from this experience are presented.

  15. Recycle of plastics from auto shredder residue: incentives and barriers

    SciTech Connect

    Curlee, T.R.

    1985-01-01

    Most of the work that has been done recently in the area of plastics recycling has focused on technological questions, and to a great extent this work has been successful. However, the degree to which recycling processes will be adopted by the market place will depend not only on technological developments but also on non-technological incentives and barriers to recycle. This paper focuses on waste plastics from the residue of auto shredders and discusses the incentives and barriers to the recycling of these plastics from three main perspectives: (1) the physical composition of shredder residue; (2) the private firm that operates a shredder and the firm that might utilize shredder residue in a recycling operation; and (3) society, which may or may not have an incentive to promote a level of recycle greater than the level provided by private firms. From each perspective significant incentives, as well as barriers, are identified that may have a pronounced impact on the degree to which plastics from shredder residue are ultimately disposed or recycled. 31 references, 5 tables.

  16. 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.

  17. 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.

  18. Toddlers at risk for paper shredder injury in the home: easy access and severe injury.

    PubMed

    Warren, Ramona C; Foltin, George L

    2006-02-01

    A 2-year-old girl sustained severe injury to 2 fingers from a home paper shredder. This case illustrates the risk of injury from paper shredders, which are increasingly common household items. Toddlers are at risk of finger injury and amputation. The US Consumer Product Safety Commission performed an investigation of reported injuries and the characteristics of paper shredders that might have contributed to the injuries, and we summarize their findings. PMID:16452378

  19. Low-speed shredder and waste shreddability tests

    SciTech Connect

    Darnell, G.R.; Aldrich, W.C.

    1983-04-01

    Most waste drums and large crates in the nuclear industry are or will be opened by hand, in gloveboxes, or with manipulators. The Transuranic Waste Treatment Facility (TWTF), which was being designed for the Idaho National Engineering Laboratory (INEL), was no exception. The TWTF's manipulator concept required 4 to 6 hours to open and route a crate or drum for further processing; a costly operation. An alternative method was sought. Four of the relatively new low-speed shredders were tested on simulated transuranic waste packaged in 55-gal drums and 4- x 4- x 4-ft boxes. Three of the shredders were capable of shredding these containers and their contents in 1 to 15 minutes. Two were able to shred typical TWTF waste to acceptable particle size. The test waste included concrete, 1/4-in. steel plate (carbon and stainless), 1-in. rebar, rock, glass, plastic, paper, cloth, wood, steel cable, chain, etc. The two shredders were able to shred drums even with unshreddable items inside; the unshreddable items lay on top for later recovery by a manipulator while the other waste was being shredded.

  20. PROCESSING EQUIPMENT FOR RESOURCE RECOVERY SYSTEMS. VOLUME III. FIELD TEST EVALUATION OF SHREDDERS

    EPA Science Inventory

    This report presents the results of a program to test and evaluate large-scale shredders used for the size reduction of solid waste. In all, tests were conducted on seven horizontal hammermills, one vertical hammermill, and one vertical ring shredder at six commercial sites. Both...

  1. 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.

  2. 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...

  3. 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.

  4. 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

  5. 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

  6. 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.

  7. 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

  8. Processing equipment for resource recovery systems. Volume 3: Field test evaluation of shredders

    NASA Astrophysics Data System (ADS)

    Savage, G. M.; Shiflett, G. R.

    1980-07-01

    A program to test and evaluate large scale shredders used for the size reduction of solid waste is reported. Tests were conducted on seven horizontal hammermills, one vertical hammermill, and one vertical ring shredder at six commercial sites. Both two stage size reduction and single stage size reduction were studied. Analytical relationships among the comminution parameters and the establishment of levels of performance for energy consumption and hammer wear associated with size reduction of solid waste are developed.

  9. 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

  10. 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.

  11. 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.

  12. Copper oxide nanoparticles can induce toxicity to the freshwater shredder Allogamus ligonifer.

    PubMed

    Pradhan, Arunava; Seena, Sahadevan; Pascoal, Cláudia; Cássio, Fernanda

    2012-11-01

    Increased commercialisation of nanometal-based products augments the possibility of their deposition into aquatic ecosystems; this, in turn, may pose risks to aquatic biota and associated ecological functions. Freshwater invertebrate shredders mostly use microbially-colonized plant litter as food resource and play an important role in aquatic detritus food webs. We assessed lethal effects of nanoCuO on the shredder Allogamus ligonifer (Trichoptera, Limnephilidae) by determining the concentration that induced 50% of death (LC(50)), and sublethal effects of nanoCuO on the feeding behaviour and growth of the shredder by exposing the animals to: (i) stream water supplemented with nanoCuO and microbially-colonized leaves, and (ii) stream water (without nanoCuO) and microbially-colonized leaves pre-exposed to nanoCuO. Results from acute lethal tests showed that the 96 h LC(50) of nanoCuO was very high (569 mg L(-1)). In the absence of nanoparticles, leaf consumption rate was 0.27 mg leaf DM mg(-1) animal DM d(-1) and the shredder growth rate was 56 μg animal DM mg(-1) animal DM d(-1). A significant inhibition in leaf consumption rate (up to 47%) and invertebrate growth rate (up to 46%) was observed when shredders were exposed to the higher tested sublethal concentration of nanoCuO (75 mg L(-1)) through either contaminated stream water or pre-contaminated food. The exposure to increased nanoCuO concentration via water or pre-contaminated food led to higher accumulation of copper in the larval body. Leached water-soluble ionic copper from the nanoCuO adsorbed or accumulated in the shredder (up to 10.2% of total Cu) seemed to influence the feeding behaviour and growth of the shredder. PMID:22749936

  13. 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

  14. 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

  15. 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. PMID:25323144

  16. 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. PMID:25719501

  17. Analysis of lead content in automotive shredder residue (ASR).

    PubMed

    Gonzalez-Fernandez, Oscar; Pessanha, Sofia; Queralt, Ignacio; Carvalho, Maria Luisa

    2009-09-01

    Automotive shredder residue (ASR) is a very heterogeneous waste, which could have a very high metal content on finest fractions phi<6 mm produced by the shredding of end of live vehicles. The approval of Directive 2000/53/EC and its transposition to the European Union member states requires an analytical technique for in-situ checking of the content of some metals in ASR wastes. The objective of this study is the evaluation of total Pb content in the different fractions using a rapid measurement method to easily accomplish the current legislation. An experimental Energy Dispersive X-ray Fluorescence (EDXRF) spectrometer with tri-axial geometry was used to analyse the ASR in order to test the feasibility of this analytical technique. Likewise, a correction of the intensities by the incoherent scattering (Compton) radiation was made to compensate the matrix effects. The results show that values in the smaller fractions are bigger (11,600 mg kg(-1) in the fraction <125 microm) than in the coarser fractions (4600 mg kg(-1) in the fraction between 2 and 6 mm) and that such type of instrumentation enables a fast measurement with a limit of detection of 1.1 mg kg(-1) for 1000 s measurement). PMID:19493667

  18. Auto shredder residue recycling: Mechanical separation and pyrolysis.

    PubMed

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

    2012-05-01

    Directive 2000/53/EC 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. PMID:22119051

  19. Analysis of lead content in automotive shredder residue (ASR)

    SciTech Connect

    Gonzalez-Fernandez, Oscar

    2009-09-15

    Automotive shredder residue (ASR) is a very heterogeneous waste, which could have a very high metal content on finest fractions {phi} < 6 mm produced by the shredding of end of live vehicles. The approval of Directive 2000/53/EC and its transposition to the European Union member states requires an analytical technique for in-situ checking of the content of some metals in ASR wastes. The objective of this study is the evaluation of total Pb content in the different fractions using a rapid measurement method to easily accomplish the current legislation. An experimental Energy Dispersive X-ray Fluorescence (EDXRF) spectrometer with tri-axial geometry was used to analyse the ASR in order to test the feasibility of this analytical technique. Likewise, a correction of the intensities by the incoherent scattering (Compton) radiation was made to compensate the matrix effects. The results show that values in the smaller fractions are bigger (11,600 mg kg{sup -1} in the fraction <125 {mu}m) than in the coarser fractions (4600 mg kg{sup -1} in the fraction between 2 and 6 mm) and that such type of instrumentation enables a fast measurement with a limit of detection of 1.1 mg kg{sup -1} for 1000 s measurement)

  20. 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. PMID:16647811

  1. A novel shredder for municipal solid waste (MSW): influence of feed moisture on breakage performance.

    PubMed

    Luo, Siyi; Xiao, Bo; Xiao, Lei

    2010-08-01

    A novel MSW shredder was presented but many aspects of the shredder have not been fully characterized. The feed moisture is an important factor that influences crushing performance. This paper focuses on the effect of feed moisture. The breakage of municipal solid waste (MSW) at several moisture levels (0%, 10%, 20%, 40% and 60%) was conducted with a laboratory shredder to investigate the effect of feed moisture on product size distribution and specific energy consumption under two different hydraulic pressures (40 and 60 kg/cm(2)). The results showed definite effects of feed moisture on the product size distribution and specific energy consumption: there is a tendency for the fine production in products to decrease with increasing amounts of water content in the feed; with the increasing feed moisture, specific energy shows an increasing trend; the specific energy and product size distribution under lower hydraulic pressure is more sensitive to the feed moisture than it is under higher hydraulic pressure. PMID:20219357

  2. 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. PMID:24814770

  3. 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.

  4. 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

  5. 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.

  6. Opportunities and Barriers to Resource Recovery and Recycling from Auto Shredder Residue - A CR3 Communication

    NASA Astrophysics Data System (ADS)

    Nayak, N.; Apelian, D.; Mishra, B.; Blanpain, B.

    2012-12-01

    TMS has forged cooperative agreements with several carefully selected organizations that actively work to benefit the materials science community. In this occasional series, JOM will provide an update on the activities of these organizations. This installment, by the Center for Resource Recovery & Recycling (CR3), focuses on auto shredder residue.

  7. 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.

  8. 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

  9. 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

  10. 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

  11. Immobilization of Harmful Elements in Fly Ash from Direct Combustion of Automobile Shredder Residue

    NASA Astrophysics Data System (ADS)

    Inoue, Ryo; Ariyama, Tatsuro

    A direct combustion method of automobile shredder residue at high temperature is considered to be an effective process, because the volume of residue can be reduced and many valuable metals can be recovered. However, the fly ash containing large amounts of heavy metals and fluorine are generated inevitably by this process. Therefore, the treatment for detoxification of this fly ash is significantly important. It is found in the present research that cement is effective on the immobilization of harmful elements in the fly ash. The hydrothermal treatment of the solidified mixture of fly ash, cement and water is also superior in the immobilization effect.

  12. Spring mounted foundation for a shredder on a refuse-to-energy project

    SciTech Connect

    Pai, P.H.; Vogelfanger, M.; Thomas, E.W. )

    1989-01-01

    This paper reports how vibration control is becoming an increasingly important consideration during the design process of power plants. The reasons discussed include equipment such as crushers and shredders that, by their function create high vibration levels, are used extensively, particularly in fossil and some alternative fuel plants, interest in minimizing plant costs and a layout for efficient operation may place high vibratory equipment adjacent to sensitive areas, and emphasis on improved reliability and longer maintenance life of equipment has manufacturers imposing tighter vibration limits on their equipment.

  13. 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. PMID:15219911

  14. The Influence of Shredder Feeding on Fungal Activity in a Nutrient-Enriched Stream and an Unaltered Stream

    NASA Astrophysics Data System (ADS)

    Chung, N.; Suberkopp, K.

    2005-05-01

    The effect of shredder feeding on aquatic hyphomycete communities associated with submerged leaves was studied in two southern Appalachian headwater streams in North Carolina. Coarse and fine mesh litter bags containing red maple (Acer rubrum) leaves were placed in the nutrient-enriched stream and in the reference stream and were retrieved monthly. Both shredder feeding and nutrient enrichment enhanced breakdown rates. The breakdown rates of leaves in coarse mesh bags in the reference stream (k = 0.0275) and fine mesh bags in the nutrient enriched stream (k = 0.0272) were not significantly different, suggesting that the shredding effect on litter breakdown was offset by higher fungal activity as a result of nutrient enrichment. Fungal sporulation rates and biomass (based on ergosterol concentrations) were higher in the nutrient enriched than in the reference stream, but neither fungal biomass nor sporulation rate was affected by shredder feeding. Species richness was higher in the nutrient-enriched than in the reference stream. The enrichment with nutrients altered fungal community composition more than shredder feeding.

  15. SIGNIFICANCE OF SIZE REDUCTION IN SOLID WASTE MANAGEMENT. VOLUME 3. EFFECTS OF MACHINE PARAMETERS ON SHREDDER PERFORMANCE

    EPA Science Inventory

    Hammermill shredders for size reduction of refuse were examined at three sites to determine the influence of key machine parameters on their performance. Internal machine configuration and single-versus two stage size reduction were studied. Key parameters that were investigated ...

  16. 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

  17. 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

  18. Ebullition of methane from peatlands: Does peat act as a signal shredder?

    NASA Astrophysics Data System (ADS)

    Ramirez, Jorge A.; Baird, Andy J.; Coulthard, Tom J.; Waddington, J. Michael

    2015-05-01

    Bubbling (ebullition) of greenhouse gases, particularly methane, from peatlands has been attributed to environmental forcings, such as changes in atmospheric pressure. However, observations from peat soils suggest that ebullition and environmental forcing may not always be correlated and that interactions between bubbles and the peat structure may be the cause of such decoupling. To investigate this possibility, we used a simple computer model (Model of Ebullition and Gas storAge) to simulate methane ebullition from a model peat. We found that lower porosity peat can store methane bubbles for lengthy periods of time, effectively buffering or moderating ebullition so that it no longer reflects bubble production signals. Our results suggest that peat structure may act as a "signal shredder" and needs to be taken into account when measuring and modeling ebullition.

  19. Energy recovery from automotive shredder residue through co-combustion with municipal solid waste

    SciTech Connect

    Mark, F.E.; Fisher, M.M.; Smith, K.A.

    1998-07-01

    This project was commissioned by the Association of Plastics Manufacturers in Europe (APME) and the American Plastics Council (APC) to evaluate the operational and environmental impacts associated with the co-combustion of automotive shredder residue (ASR) with municipal solid waste (MSW) in a modern, commercial waste-to-energy plant. This paper describes the shredding and combustion facilities utilized for the program, discusses study protocols and test results, and presents analytical results of ASR characterizations, raw and clean boiler gas sampling and solid residues sampling. The study concludes that cocombustion of ASR and MSW improved burnout, did not adversely impact boiler performance, stack emissions or disposal or the combustion residues (ash) and is, therefore, an environmentally sound method of recovering the energy value in ASR.

  20. 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

  1. 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

  2. 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). PMID:24934194

  3. Co-combustion of shredder residues and municipal solid waste in a Swedish municipal solid waste incinerator.

    PubMed

    Redin, L A; Hjelt, M; Marklund, S

    2001-12-01

    Incinerating automotive shredder residue (ASR) in order to increase the recovery from end of life vehicles (ELVs) is an attractive option when recycling this material. In this study, incineration combined with energy recovery, was investigated. The incineration experiments, where 20% shredder residue (SR) was burnt with conventional municipal solid waste (MSW), were conducted in a full-scale MSW horizontal grate incinerator. Measurements were made before, during and after the incineration. The results showed some minor increases in the emission levels of raw gases sampled after an electrostatic filter, but almost no significant differences when sampled after a wet scrubber. An increased level of 'non-toxic' metals was detected within the bottom ash. It was concluded that refined SR, in small quantities, is suitable to add to MSW. PMID:12201681

  4. Recycling of automobile shredder residue with a microwave pyrolysis combined with high temperature steam gasification.

    PubMed

    Donaj, Pawel; Yang, Weihong; Błasiak, Włodzimierz; Forsgren, Christer

    2010-10-15

    Presently, there is a growing need for handling automobile shredder residues--ASR or "car fluff". One of the most promising methods of treatment ASR is pyrolysis. Apart of obvious benefits of pyrolysis: energy and metals recovery, there is serious concern about the residues generated from that process needing to be recycled. Unfortunately, not much work has been reported providing a solution for treatment the wastes after pyrolysis. This work proposes a new system based on a two-staged process. The ASR was primarily treated by microwave pyrolysis and later the liquid and solid products become the feedstock for the high temperature gasification process. The system development is supported within experimental results conducted in a lab-scale, batch-type reactor at the Royal Institute of Technology (KTH). The heating rate, mass loss, gas composition, LHV and gas yield of producer gas vs. residence time are reported for the steam temperature of 1173 K. The sample input was 10 g and the steam flow rate was 0.65 kg/h. The conversion reached 99% for liquids and 45-55% for solids, dependently from the fraction. The H(2):CO mol/mol ratio varied from 1.72 solids and 1.4 for liquid, respectively. The average LHV of generated gas was 15.8 MJ/Nm(3) for liquids and 15 MJ/Nm(3) for solids fuels. PMID:20580160

  5. Efficient dehalogenation of automobile shredder residue in NaOH/ethylene glycol using a ball mill.

    PubMed

    Kameda, Tomohito; Fukuda, Yuuzou; Park, Kye-Sung; Grause, Guido; Yoshioka, Toshiaki

    2009-01-01

    We investigated the effectiveness of sodium hydroxide/ethylene glycol (NaOH/EG) for dehalogenation of automobile shredder residue (ASR) using a ball mill. Efficient dehalogenation was achieved at atmospheric pressure by combining the use of EG (196 degrees C b.p.) as a replacement solvent for NaOH with ball milling, which improved contact between ASR and OH(-) in solution. Moderate NaOH concentrations and increased ball mill rotation speeds produced high dechlorination that was not significantly affected by the weight ratio of ASR to EG. NaOH/EG dechlorination increased with temperature with an apparent activation energy of 50 kJ mol(-1) confirming that the reaction proceeded under chemical reaction control. The modified shrinking-core model was appropriate to explain the dechlorination process. Low chloro levels in our NaOH/EG-treated ASR suggested that this material could be used for feedstock recycling and the wet process may be applicable for dehalogenation of other important waste streams. PMID:18929394

  6. 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. PMID:24373677

  7. 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

  8. 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.

  9. 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

  10. 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. PMID:25690411

  11. 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. PMID:24140377

  12. 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

  13. 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.

  14. 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. PMID:20541864

  15. 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

  16. 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

  17. 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.

  18. 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

  19. 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

  20. 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

  1. 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

  2. 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. PMID:26525968

  3. 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. PMID:26482807

  4. 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

  5. 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.

  6. 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. PMID:23856312

  7. 7 CFR 58.708 - Grinders or shredders.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... AGRICULTURAL MARKETING ACT OF 1946 AND THE EGG PRODUCTS INSPECTION ACT (CONTINUED) GRADING AND INSPECTION... contamination of the cheese and to allow thorough cleaning of all parts and product contact surfaces....

  8. The Atacama Desert Cave Shredder: A Case for Conduction Thermodynamics

    NASA Astrophysics Data System (ADS)

    Titus, T. N.; Wynne, J. J.; Ruby, D.; Cabrol, N.

    2010-03-01

    In the Atacama Desert, where caves are quite dry, the interior rock temperature should be a function of only the thermal conduction through the rock, which is driven by the mean temperature at the surface. In this paper, we test this hypothesis.

  9. 78 FR 79006 - Certain Paper Shredders, Certain Processes for Manufacturing or Relating to Same and Certain...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-27

    .... Ltd. 78 FR 5496-97. The complaint alleges violations of section 337 of the Tariff Act of 1930, as... Ltd.; Jiangsu New United Office Equipments Co. Ltd.; Shenzhen Elite Business Office Equipment Co. Ltd.; Elite Business Machines Ltd.; New United Office Equipment USA, Inc.; Jiangsu Shinri Machinery Co....

  10. 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...

  11. 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.

  12. 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.

  13. 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

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

    SciTech Connect

    Coates, Gareth Rahimifard, Shahin

    2009-01-15

    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.

  15. [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.

  16. [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.

  17. 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

  18. 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...

  19. 76 FR 66913 - Procurement List Proposed Additions and Deletions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-28

    ... from the Procurement List: Products NSN: 7490-01-483-8984--Paper Shredder, Cross Cut NSN: 7490-01-483-8985--Paper Shredder, Strip Cut NSN: 7490-01-483-8990--Paper Shredder, Strip Cut NSN: 7490-01-483-8991--Paper Shredder, Cross Cut NPA: L.C. Industries for the Blind, Inc., Durham, NC Contracting...

  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. PMID:21440364

  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. 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.

  5. 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)

  6. Predicting richness effects on ecosystem function in natural communities: insights from high-elevation streams.

    PubMed

    Dangles, Olivier; Crespo-Pérez, Verónica; Andino, Patricio; Espinosa, Rodrigo; Calvez, Roger; Jacobsen, Dean

    2011-03-01

    . Despite the increased complexity of experimental and theoretical studies on the biodiversity-ecosystem functioning (B-EF) relationship, a major challenge is to demonstrate whether the observed importance of biodiversity in controlled experimental systems also persists in nature. Due to their structural simplicity and their low levels of human impacts, extreme species-poor ecosystems may provide new insights into B-EF relationships in natural systems. We address this issue using shredder invertebrate communities and organic matter decomposition rates in 24 high-altitude (3200-3900 m) Neotropical streams as a study model. We first assessed the effects of stream characteristics and shredder diversity and abundance on organic matter decomposition rates in coarse- and fine-mesh bags. We found the interaction term shredder richness x shredder abundance had the most significant impact on decomposition rates in the field, although water discharge may also play a role locally. We also examined the relative contribution of the three most abundant shredders on decomposition rates by manipulating shredder richness and community composition in a field experiment. Transgressive overyielding was detected among the three shredder species, indicating complementary resource use and/or facilitation. By integrating survey and experimental data in surface response analyses we found that observed B-EF patterns fit those predicted by a linear model that described litter decomposition rates as a function of increasing shredder richness and the relative abundance of the most efficient shredders. Finally, the validity of our approach was tested in a broader context by using two independent but comparable data sets from 49 French and Swedish streams showing more complex shredder community structure. Results revealed that richness and identity effects on decomposition rates were lost with increasing shredder community complexity. Our approach of combining experimental and empirical data

  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. Do Invertebrate Activity and Current Velocity Affect Fungal Assemblage Structure in Leaves?

    NASA Astrophysics Data System (ADS)

    Ferreira, Verónica; Graça, Manuel A. S.

    2006-02-01

    In this study we assessed the effect of current velocity and shredder presence, manipulated in artificial channels, on the structure of the fungal assemblage colonizing alder (Alnus glutinosa (L.) Gaertner) leaves incubated in coarse and fine mesh bags. Fungal sporulation rates, cumulative conidial production and number of species of aquatic hyphomycetes were higher in leaves exposed to high rather than to low current velocity. The opposite was observed regarding Simpson's index (D) on the fungal assemblage. Some species of aquatic hyphomycetes were consistently stimulated in high current channels. No effect of shredders or of mesh type was observed.

  10. 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.

  11. 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...

  12. 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.

  13. 40 CFR 63.1517 - Records

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... occurrence, measurement, maintenance, corrective action, report, or record. The most recent 2 years of...; and (3) The owner or operator may report required information on paper or on a labeled computer disk... aluminum scrap shredder is subject to visible emission observation requirements, records of all Method...

  14. 40 CFR 63.1517 - Records

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... occurrence, measurement, maintenance, corrective action, report, or record. The most recent 2 years of...; and (3) The owner or operator may report required information on paper or on a labeled computer disk... aluminum scrap shredder is subject to visible emission observation requirements, records of all Method...

  15. 40 CFR 63.1517 - Records

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... occurrence, measurement, maintenance, corrective action, report, or record. The most recent 2 years of...; and (3) The owner or operator may report required information on paper or on a labeled computer disk... aluminum scrap shredder is subject to visible emission observation requirements, records of all Method...

  16. Recycling and the automobile

    SciTech Connect

    Holt, D.J.

    1993-10-01

    This article examines the current status of automobile recycling and contains a summary of a survey which points out the major drivers and their impacts on automotive recycling. The topics of the article include computerized dismantling, polyurethane, sheet molding compound, polyester, thermoplastic polyester, recycling salvaged parts, vinyl and automotive shredder residue.

  17. SIGNIFICANCE OF SIZE REDUCTION IN SOLID WASTE MANAGEMENT. VOLUME 2

    EPA Science Inventory

    This report presents results of shredder tests using raw municipal solid waste, air-classified light fraction, and screened light fraction. The tests simulated single- and multiple-stage size reduction, using a 10-ton per hour swing hammermill and a small, high-speed fixed hammer...

  18. Argonne National Laboratory's Recycling Pilot Plant

    ScienceCinema

    Spangenberger, Jeff; Jody, Sam;

    2013-04-19

    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. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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.

  4. 7 CFR 58.726 - Cutting and grinding.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Cutting and grinding. 58.726 Section 58.726... Procedures § 58.726 Cutting and grinding. The trimmed and cleaned cheese should be cut into sections of convenient size to be handled by the grinder or shredder. The grinding and mixing of the blended lots...

  5. 7 CFR 58.726 - Cutting and grinding.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Cutting and grinding. 58.726 Section 58.726... Procedures § 58.726 Cutting and grinding. The trimmed and cleaned cheese should be cut into sections of convenient size to be handled by the grinder or shredder. The grinding and mixing of the blended lots...

  6. 7 CFR 58.726 - Cutting and grinding.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Cutting and grinding. 58.726 Section 58.726... Procedures § 58.726 Cutting and grinding. The trimmed and cleaned cheese should be cut into sections of convenient size to be handled by the grinder or shredder. The grinding and mixing of the blended lots...

  7. FERROUS METALS RECOVERY AT RECOVERY 1, NEW ORLEANS: PERFORMANCE OF THE MODIFIED SYSTEM. TEST NO. 4.05 AND TEST NO. 4.09, RECOVERY 1, NEW ORLEANS

    EPA Science Inventory

    This report documents two series of samplings and the monitoring of enery consumption and shredder hammer wear of the upgraded ferrous recovery system that produces a light ferrous product from the processing of municipal refuse at the New Orleans resource recovery project. A ser...

  8. Influence of Initial Leaf Pack Size on Estimates of Breakdown Rates in Streams

    NASA Astrophysics Data System (ADS)

    Stone, M. L.; Whiles, M. R.; McTammany, M. E.; Gallo, T. M.

    2005-05-01

    Experiments to determine the influence of leaf pack size on estimates of breakdown rates were conducted in Stony Run, a moderately hardwater stream in central Pennsylvania draining mature second-growth forest. We deployed 5-mm mesh bags containing different initial amounts (2, 5, 10, 20, and 50 g) of white oak leaves at 3 sites in Stony Run during October 2004. Bags have been retrieved monthly and were processed to determine ash-free dry mass remaining and abundance of shredder-detritivores in the bags. Breakdown rates varied from 0.018 d-1 in 50 g bags to 0.015 d-1 in 2 g bags and were strongly correlated with initial weight of leaf litter (log10 initial leaf mass vs. breakdown rate r = 0.99). Total invertebrate abundance was initially higher in heavier leaf bags, and proportion of shredders increased as leaf mass declined throughout the study. Shredder abundance was positively correlated with leaf pack size (r = 0.76) and breakdown rate (r = 0.82), which indicates that shredders were more important in determining breakdown rates than mechanical fragmentation or microbial activity. These results suggest that models of stream organic matter dynamics should incorporate distribution of natural leaf packs and higher breakdown rates associated with densely packed leaves.

  9. Chemical characteristics and methane potentials of source-separated and pre-treated organic municipal solid waste.

    PubMed

    Hansen, T L; Svärd, A; Angelidaki, I; Schmidt, J E; Jansen, J; Christensen, T H

    2003-01-01

    A research project has investigated the biogas potential of pre-screened source-separated organic waste. Wastes from five Danish cities have been pre-treated by three methods: screw press; disc screen; and shredder and magnet. This paper outlines the sampling procedure used, the chemical composition of the wastes and the estimated methane potentials. PMID:14531442

  10. 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

  11. 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.

  12. 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.

  13. Invertebrates control metals and arsenic sequestration as ecosystem engineers.

    PubMed

    Schaller, Jörg; Weiske, Arndt; Mkandawire, Martin; Dudel, E Gert

    2010-03-01

    Organic sediments are known to be a significant sink of inorganic elements in polluted freshwater ecosystems. Hence, we investigated the role of invertebrate shredders (the freshwater shrimp Gammarus pulex L.) in metal and arsenic enrichment into organic partitions of sediments in a wetland stream at former uranium mining site. Metal and metalloid content in leaf litter increased significantly during decomposition, while at the same time the carbon content decreased. During decomposition, G. pulex as a ecosystem engineer facilitated significantly the enrichment of magnesium (250%), manganese (560%), cobalt (310%), copper (200%), zinc (43%), arsenic (670%), cadmium (100%) and lead (1340%) into small particle sizes. The enrichments occur under very high concentrations of dissolved organic carbon. Small particles have high surface area that results in high biofilm development. Further, the highest amounts of elements were observed in biofilms. Therefore, invertebrate shredder like G. pulex can enhance retention of large amounts of metal and arsenic in wetlands. PMID:20132960

  14. 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.

  15. 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.

  16. Effect of Climate-Related Change in Vegetation on Leaf Litter Consumption and Energy Storage by Gammarus pulex from Continental or Mediterranean Populations

    PubMed Central

    Foucreau, Natacha; Piscart, Christophe; Puijalon, Sara; Hervant, Frédéric

    2013-01-01

    As a consequence of global warming, it is important to characterise the potential changes occurring for some functional processes through the intra-specific study of key species. Changes in species distribution, particularly when key or engineer species are affected, should contribute to global changes in ecosystem functioning. In this study, we examined the potential consequences induced by global warming on ecosystem functioning in term of organic matter recycling. We compared consumption of leaf litter by some shredder populations (Gammarus pulex) between five tree species inhabiting continental (i.e., the northern region of the Rhône River Valley) and/or Mediterranean (i.e., the southern region of the Rhône River Valley) conditions. To consider any potential adaptation of the gammarid population to vegetation in the same climate conditions, three populations of the key shredder Gammarus pulex from the northern region and three from the southern region of the Rhône River Valley were used. We experimentally compared the effects of the geographical origin of both the gammarid populations and the leaf litter species on the shredding activity and the physiological state of animals (through body triglyceride content). This study demonstrated that leaf toughness is more important than geographical origin for determining shredder leaf litter consumption. The overall consumption rate of the gammarid populations from the southern region of Rhône Valley was much higher than that of the populations from the northern region, but no clear differences between the origins of the leaf litter (i.e., continental vs. Mediterranean) were observed. The northwards shift of G. pulex populations adapted to warmer conditions might significantly modify organic matter recycling in continental streams. As gammarid populations can demonstrate local adaptations to certain leaf species as a trophic resource, changes in riparian vegetation associated with climate change might locally

  17. 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.

  18. Impacts of warming on aquatic decomposers along a gradient of cadmium stress.

    PubMed

    Batista, D; Pascoal, C; Cássio, F

    2012-10-01

    We evaluated the effects of cadmium and temperature on plant-litter decomposition by examining diversity and activity of aquatic fungi and leaf consumption by Limnephilus sp., a typical invertebrate shredder of Iberian streams. Freshly fallen leaves were immersed in a stream to allow microbial colonization, and were exposed in microcosms to a gradient of cadmium (≤11 levels, ≤35 mg L(-1)). Microcosms were kept at 15 °C, a temperature typically found in Iberian streams in autumn, and at 21 °C to simulate a warming scenario. The increase in temperature stimulated leaf decomposition by microbes, fungal reproduction and leaf consumption by the shredder. Conversely, increased cadmium concentrations inhibited fungal reproduction and diversity, and leaf consumption by the invertebrate. Cadmium concentration inhibiting 50% of fungal reproduction, microbial decomposition and leaf consumption by the shredder was higher at 15 °C than at 21 °C, suggesting that higher temperatures can lead to increased metal toxicity to aquatic decomposers. PMID:22683478

  19. 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

  20. End-of-Life Vehicles management: Italian material and energy recovery efficiency.

    PubMed

    Santini, Alessandro; Morselli, Luciano; Passarini, Fabrizio; Vassura, Ivano; Di Carlo, Salvatore; Bonino, Francesco

    2011-03-01

    Each European Member State must comply with Directive 2000/53/EC recycling and recovery targets by 2015, set to 85% and 95%, respectively. This paper reports a shredder campaign trial developed and performed in Italy at the beginning of 2008. It turns out to be the first assessment about the critical aspects belonging to the Italian End-of-Life Vehicles (ELVs) reverse supply chain involving 18 dismantling plants, a shredder plant and 630 ELV representatives of different categories of vehicles treated in Italy during 2006. This trial aims at improving the experimental knowledge related to ELVs added waste, pre-treatment, part reuse, recycling and final metal separation and car fluff disposal. Finally, the study also focuses on the calculation of the effective Italian ELV recycling rate, which results equal to 80.8%, and auto shredder residue (ASR) characterization. According to the results obtained in this work, ASR still contains up to 8% of metals and 40% of polymers that could be recovered. Moreover, physical-chemical analysis showed a Lower Heat Value of almost 20,000 kJ/kg and revealed the presence of pollutants such as heavy metals, mineral oils, PCBs and hydrocarbons. PMID:20943364

  1. 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.

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

    PubMed

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

    2011-05-01

    AV Miljø 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(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(4) (70%) and carbon dioxide (CO(2)) (29%) whereas the gas generated within the shredder waste, primarily consisted of CH(4) (27%) and nitrogen (N(2)) (71%), containing no CO(2). The results indicated that the gas composition in the shredder waste was governed by chemical reactions as well as microbial reactions. CH(4) mass balances from three individual waste cells showed that a significant part (between 15% and 67%) of the CH(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(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(4) emission from the disposal site was found to be 820 ± 202 kg CH(4)d(-1). The total emission rate through the leachate

  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. 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

  5. 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

  6. Robots remove explosive waste from flooded site

    SciTech Connect

    Not Available

    1993-10-01

    Explosive industrial waste can remain hazardous for years, making remediation extremely dangerous, particularly when using traditional methods involving people and manually operated equipment. The work is even more complex if the waste is submerged. Authorities in 1988 faced an unusual challenge when they decided to clean up a flooded area that had been used for more than 30 years as a dump for explosive materials. They devised an innovative but highly effective solution. Instead of using divers, two robots perform the cleanup while site personnel remain 600 feet away from the restricted area. The robots were developed by Sonsub Environmental Services Inc. (Houston), which is responsible for their operation. The robots initially located and cleared a small area underwater to set up a metal-processing system, which also was designed by Sonsub. The system is similar to a metal-recycling shredder. The robots then assembled the 25-foot-tall, 20-ton system 60 feet below the surface on the pit floor. A large, surface robot carried sections of the shredder to the cleared area and lowered them, while a smaller, submersible robot guided them into position. This required extreme precision by the smaller robot, which had to ensure that sections mated properly. Both robots now retrieve waste from the pit bottom and feed it into the shredder. The larger robot has a 40-foot jointed arm for lifting up to 1,000 pounds of debris, a manipulator hand for sorting through rock piles and removing small containers, and a grapple for picking up items from the pit floor.

  7. 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

  8. 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)

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Characterization of pyrolysis oils obtained from non-conventional sources

    SciTech Connect

    Houde, J. Jr.; Charland, J.P.

    1995-12-31

    Research in the field of recycling which focusses on generating oil by pyrolysis or thermal conversion has increased considerably, in recent years. CANMET has developed an application for oil for use as an additive in the manufacture of asphalt. The oil is obtained by thermal conversion of municipal sewage sludge. A program is now under way to examine oils obtained from other sources. The project characterizes pyrolysis oils from automobile shredder residue and pulp and paper mill sludge. Analytical results will be presented as well as a comparison of these oils with those obtained from tires and municipal sewage sludge.

  14. 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.

  15. The development of vehicle recycling in Europe: Sorting, shredding, and separation

    NASA Astrophysics Data System (ADS)

    Dalmijn, W. L.; de Jong, T. P. R.

    2007-11-01

    The large scale mechanical processing of end-of-life vehicles (ELVs) started in the United States and was improved in Europe. In the United States, ELV recycling focused on high volumes while in Europe, optimization of processing plants was directed at high grades and recoveries. Legislation by the European Commission (EC) and the fast-growing consumption of metals in China has created an uneven playing field and new markets, which influences the technological developments in the United States and the European Union. In the Netherlands, the EC legislation has been implemented by car dismantling and in the future, mechanical auto shredder residue processing will be added to reduce cost.

  16. 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.

  17. 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.

  18. 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.

  19. Microwave modification of sugar cane to enhance juice extraction during milling.

    PubMed

    Brodie, Graham; Harris, Gerard; Jacob, Mohan V; Sheehan, Madoc; Yin, Ling

    2011-01-01

    Sugar extraction from cane requires shredding and crushing, both of which are energy intensive activities. Cane shredders account for almost 30% of the total power requirements for the juice extraction train in a sugar mill with four mills. Shredder hammers also wear quickly during the crushing season and need to be regularly maintained or replaced. Microwave pre-treatment of other plant based materials has resulted in significant reductions in total processing energy. This paper briefly reviews the underlying structure of sugar cane and how microwave pre-treatment may interact with sugar cane. Microwave treatment reduced the strength of sugar cane samples to 20% of its untreated value. This strength reduction makes it easier to crush the cane and leads to a 320% increase in juice yield compared with untreated cane when cane samples were crushed in a press. There was also a 68% increase in Brix %, a 58% increase in total dissolved solids, a 58% reduction in diffusion time, a 39% increase in Pol%, and a 7% increase in juice purity compared with the control samples after 60 minutes of diffusion in distilled water. PMID:24428107

  20. 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

  1. Formation characteristics of PCDD and PCDF during pyrolysis processes.

    PubMed

    Weber, R; Sakurai, T

    2001-12-01

    In recent years, pyrolysis processes have become technologies developed to industrial scale and discussed as alternatives to the existing waste combustion technology. However, little information is published regarding PCDD/F formation characteristics during pyrolysis processes. Two common shredder fractions--industrial light shredder (ILS) and refrigerators (REF)--both with high chlorine and copper content were pyrolysed for this pyrolysis study using a pilot plant with a capacity of 100 kg/h. At oxygen concentrations below 2% and temperatures between 430 degrees C and 470 degrees C, considerable amounts of PCDD/F were formed during the pyrolysis. More than 90% of total TEQ was found in the oil fraction (gas phase). The PCDD/PCDF ratio and the homologue pattern differed significantly from those formed during waste incineration. Considering mono- to octachlorinated congeners, up to 400 times more PCDF were formed compared to PCDD. For the investigated pyrolysis conditions, the formation of low chlorinated congeners was highly favoured. The distribution of TEQ within the individual congeners were very similar in all investigated runs. More than 80% of total TEQ stem from 2,3,7,8-substituted T4CDF and P5CDF. The isomer pattern, however, did not show significant differences compared to the common waste incineration pattern suggesting that the basic formation routes are similar. PMID:11695624

  2. AFBC co-firing of coal and hospital wastes

    SciTech Connect

    Not Available

    1992-01-01

    During the previous report period, shredder system verification and testing was initiated at DONLEE's pilot facility located in York, Pennsylvania. General waste from the Lebanon VA Medical Center was transported to the pilot facility in York. The waste was fed into the unit starting December 18, 1991. The waste feed rate was adjusted to approximately 150 lb./hr. The stack monitoring portion of the shredder testing was conducted on January 28 and 29. The heat input was approximately 6 [times] l0[sup 6] BTU/hr. both days. On the first day, only coal and limestone were fed into the unit. On the second day, hospital waste, coal, and limestone were fed into the unit. On both days of testing, data included: coal, limestone, and ash samples and flow rates; all air flows; stack flue gas flow; combustor, cyclone, boiler, and baghouse; temperatures and pressures; stack concentration of dioxins and furans; stack concentration of heavy metals; stack concentration of HCI; stack concentration of PAH. The hospital waste feed during the second test was approximately 150 lb./hr. The PA DER requested that the final design of the Lebanon facility fire anthracite coal only. On February 4, the unit was lit off on anthracite coal. Operation on anthracite stabilized at a 1650 degree F combustor temperature. Hospital waste was fed into the unit while on anthracite without incident.

  3. AFBC co-firing of coal and hospital wastes. Quarterly technical progress report, February 15, 1992--May 15, 1992: Phase 1

    SciTech Connect

    Not Available

    1992-12-01

    During the previous report period, shredder system verification and testing was initiated at DONLEE`s pilot facility located in York, Pennsylvania. General waste from the Lebanon VA Medical Center was transported to the pilot facility in York. The waste was fed into the unit starting December 18, 1991. The waste feed rate was adjusted to approximately 150 lb./hr. The stack monitoring portion of the shredder testing was conducted on January 28 and 29. The heat input was approximately 6 {times} l0{sup 6} BTU/hr. both days. On the first day, only coal and limestone were fed into the unit. On the second day, hospital waste, coal, and limestone were fed into the unit. On both days of testing, data included: coal, limestone, and ash samples and flow rates; all air flows; stack flue gas flow; combustor, cyclone, boiler, and baghouse; temperatures and pressures; stack concentration of dioxins and furans; stack concentration of heavy metals; stack concentration of HCI; stack concentration of PAH. The hospital waste feed during the second test was approximately 150 lb./hr. The PA DER requested that the final design of the Lebanon facility fire anthracite coal only. On February 4, the unit was lit off on anthracite coal. Operation on anthracite stabilized at a 1650 degree F combustor temperature. Hospital waste was fed into the unit while on anthracite without incident.

  4. Stream Restoration Effects on an Impaired Benthic Macroinvertebrate Community in a Small Coastal Plain Stream in Johnston County, North Carolina.

    NASA Astrophysics Data System (ADS)

    Price, G. W.; Roessler, C. E.

    2005-05-01

    Pre- and post-construction benthic macroinvertebrate community data were collected from a recently restored small coastal plain stream in North Carolina. Metrics for comparing two sites, a restoration and a reference reach, included total and EPT taxa richness, total and EPT biotic indices (BIs), and EPT abundance. Initially, the restoration site scored worse than the reference site on every metric and indicated an impaired status for biological integrity, the stream's primary designated use. Two years after restoration, metric values for the restoration site have improved, while those for the reference site remained stable. EPT taxa richness has nearly doubled from 7 to 13 taxa, exceeding that of the reference site. However, BIs at the restoration site, while improving, remain worse than those of the reference site, suggesting that the restoration site community has not yet stabilized. This conclusion is supported by the lesser number of shredders found at the restoration site than the reference site. However, it is anticipated that the restoration shredder population will grow as organic matter input from maturing riparian vegetation increases. These observations suggest that stream restoration can be an effective management tool for restoring biological integrity, as measured by benthic macroinvertebrate communities.

  5. New technological developments in processing solid waste to energy

    SciTech Connect

    Sherwin, E.T.; Nollet, A.R.

    1980-01-01

    The state-of-the-art in production of energy from municipal solid waste outlining relative advantages, limitations, and economics of various systems is briefly reviewed including mass-burning versus RDF in spreader-stoker fired boilers; suspension-firing of RDF; pulverized fuel; pelletized fuels; and gaseous fuels generated by pyrolysis processes. A new system for processing solid waste for resource recovery separates the incoming waste by air-classification as the first processing step; conventional systems shred as the first processing step. This new system, originally developed to guard against shredder explosions, has the following supplemental advantages: produces a refuse-derived fuel (RDF) having higher heating values and less ash than conventional systems; and reclaims waste paper which can be used as paper-making furnish, utilizing current beneficiating and cleaning techniques. Production of paper from virgin materials requires 20 to 30 million Btu per ton of paper - versus 10 million Btu when waste paper is utilized as furnish. A new system proposed for storage, handling, and feeding refuse-derived fuel to large suspension-fired boilers is examined. This system proposes coarse shredding only of the light fraction at the solid waste processing plant; shipment in compactor trailers; storage in the same trailers; fine-shredding near the boiler; and air transport from the shredders using material handling fans injecting directly into the boilers. This system provides more efficient operation at less capital cost than systems utilized to date.

  6. 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. PMID:21149322

  7. Macroinvertebrate assemblages and secondary production in three wood-poor, second-growth, headwater streams in the Upper Peninsula of Michigan.

    NASA Astrophysics Data System (ADS)

    Entrekin, S. A.; Rosi-Marshall, E. J.; Tank, J. L.; Lamberti, G. A.

    2005-05-01

    Benthic organic matter (BOM) is retained by in-stream wood in forested streams and is often the primary food resource for aquatic macroinvertebrates. We sampled BOM and macroinvertebrates in three, forested headwater streams within the same watershed and predicted that BOM standing stocks would be high and, therefore, macroinvertebrate functional feeding groups would be dominated by shredders and gatherers. However, all streams had low annual average standing stocks of BOM (75 to 166 gAFDM m-2), and low shredder biomass (<5% of total) and gatherer biomass (<10%). Shane and Walton Creek macroinvertebrate biomass was dominated by predators (48% of total), scrapers (20%), and filterers (13%). Macroinvertebrate abundance peaked in June-July and again in November, while biomass peaked in November. In contrast, State Creek was dominated by scrapers (51%) and predators (33%), and abundance and biomass peaked in March and May, respectively. State Creek had the highest annual mean abundance (1198 individuals m-2), biomass (427 mgDM m-2), and secondary production (1000 mgDM m-2 yr-1). Macroinvertebrates in State Creek likely relied on algae and bryophytes for food and habitat. We conclude that macroinvertebrate communities in these streams are limited by BOM that was not retained in-stream because of reduced wood inputs from past logging.

  8. 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

  9. 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.

  10. POP bioaccumulation in macroinvertebrates of alpine freshwater systems.

    PubMed

    Bizzotto, E C; Villa, S; Vighi, M

    2009-12-01

    This study serves to investigate the uptake of POPs in the different trophic levels (scrapers, collectors, predators, shredders) of macroinvertebrate communities sampled from a glacial and a non-glacial stream in the Italian Alps. The presented results show that the contaminant concentrations in glacial communities are generally higher compared to those from non-glacial catchments, highlighting the importance of glaciers as temporary sinks of atmospherically transported pollutants. Moreover, the data also suggests that in mountain systems snow plays an important role in influencing macroinvertebrate contamination. The main chemical uptake process to the macroinvertebrates is considered to be bioconcentration from water, as similar contaminant profiles were observed between the different trophic levels. The role of biomagnification/bioaccumulation is thought to be absent or negligible. The enrichment of chemicals observed in the predators is likely to be related to their greater lipid content compared to that of other feeding groups. PMID:19570599

  11. The functional and physiological status of Gammarus fossarum (Crustacea; Amphipoda) exposed to secondary treated wastewater.

    PubMed

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

    2011-01-01

    Climate change scenarios predict lower flow rates during summer that may lead to higher proportions of wastewater in small and medium sized streams. Moreover, micropollutants (e.g. pharmaceuticals and other contaminants) continuously enter aquatic environments via treated wastewater. However, there is a paucity of knowledge, whether extended exposure to secondary treated wastewater disrupts important ecosystem functions, e.g. leaf breakdown. Therefore, the amphipod shredder Gammarus fossarum was exposed to natural stream water (n=34) and secondary treated wastewater (n=32) for four weeks in a semi-static test system under laboratory conditions. G. fossarum exposed to wastewater showed significant reductions in feeding rate (25%), absolute consumption (35%), food assimilation (50%), dry weight (18%) and lipid content (22%). Thus, high proportions of wastewater in the stream flow may affect both the breakdown rates of leaf material and thus the availability of energy for the aquatic food web as well as the energy budget of G. fossarum. PMID:20932616

  12. 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.

  13. 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

  14. 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. PMID:26896099

  15. Producing ground scrap tire rubber: A comparison between ambient and cryogenic technologies

    SciTech Connect

    Blumenthal, M.H.

    1996-09-01

    Prior to 1985, few, if any scrap tires were processed. The Minnesota program changed all that. The equipment first introduced to process scrap tires consisted of redesigned wood or metal shredders. The performance of these systems left much to be desired. In the past 10 years, many companies and equipment systems, designed especially for scrap tires, have come into existence. Until recently, scrap tires were typically processed by ambient systems. These systems consist of a mechanical process, which cuts and or grinds whole tire rubber into the desired sized particle at room temperatures. Historically, producing ground rubber, like all other rubber processing, was done by an ambient processes system. Within the last several years, cryogenic processing of scrap tires has been introduced for the preparation of ground rubber. In the cryogenic process, rubber is introduced into a bath of liquid nitrogen, instantly freezing the rubber. Once embrittled, the rubber is struck with an impact devise, effectively shattering the rubber.

  16. Screening of halogenated aromatic compounds in some raw material lots for an aluminium recycling plant.

    PubMed

    Sinkkonen, Seija; Paasivirta, Jaakko; Lahtiperä, Mirja; Vattulainen, Antero

    2004-05-01

    Four samples of scrap raw materials for an aluminium recycling plant were screened for the occurrence of persistent halogenated aromatic compounds. The samples contained waste from handling of electric and electronic plastics, filter dust from electronic crusher, cyclone dust from electronic crusher and light fluff from car shredder. In our screening analyses, brominated flame retardants were observed in all samples. Polybrominated diphenyl ethers (PBDE) were identified in all samples in amounts of 245-67450 ng/g. The major PBDE congeners found were decabromo- and pentabromodiphenyl ethers. 1,1-bis(2,4,6-tribromophenoxy)ethane, hexabromobenzene, ethyl-pentabromobenzene, tetrabromobisphenol-A, pentabromotoluene and dimethyl tetrabromobenzene were observed in all scrap samples. The concentrations of PCBs, PCNs (polychlorinated naphthalenes) and nona- to undecachlorinated terphenyls in some of these scrap samples were remarkably high. PMID:14987867

  17. The larva of Athripsodes genei (Rambur 1842) (Trichoptera, Leptoceridae).

    PubMed

    Waringer, Johann; Graf, Wolfram

    2014-01-01

    This paper describes the previously unknown larva of Athripsodes genei (Rambur 1842). Information on the morphology of the 5th larval instar is given and the most important diagnostic features are illustrated. In the context of existing identification keys the larva of A. genei keys together with A. albifrons (Linnaeus 1758), A. commutatus (Rostock 1874), A. leucophaeus (Rambur 1842) and Athripsodes tavaresi (Navás 1916). These species differ in the number of ventral edge setae at the 1st tibia and in the shape and colour of the submentum. With respect to zoogeography, Athripsodes genei is a (micro-)endemic of the collin and planar regions of Sardinia and Corsica (Graf et al. 2008). According to mandible morphology, A. genei is a collector-gatherer, shredder and, to a minor extent, also a predator. PMID:25283900

  18. Remediation of a uranium-contaminated quarry utilizing submersible, remotely operated vehicles. Environmental Restoration Program

    SciTech Connect

    Fleming, K.N.

    1992-10-22

    The Kerr Hollow Quarry (KHQ) Disposal Site on the Oak Ridge (Tennessee) Reservation was previously used to treat and dispose of pyrophoric and water-reactive wastes contaminated with small quantities of radioactive materials (almost exclusively uranium and uranium daughters) from processes at the Department of Energy-owned, Oak Ridge Y-12 Plant and Oak Ridge National Laboratory. This paper describes remediation techniques utilizing a small, remotely operated submarine with an attached camera to visually locate waste containers, determine whether containers have been breached, transport small containers, and direct a larger remotely operated grappling machine to move larger waste for shredding operations. Most of the solid waste is reduced under water by a metal shredder. Non-shreddable items (e. g. , gas cylinders and larger structures) are mechanically breached under water to allow the contents to fully react. The waste is then removed from the water, monitored, the material is segregated, and transported to a temporary waste storage area until disposal.

  19. Remediation of a uranium-contaminated quarry utilizing submersible, remotely operated vehicles

    SciTech Connect

    Fleming, K.N.

    1992-10-22

    The Kerr Hollow Quarry (KHQ) Disposal Site on the Oak Ridge (Tennessee) Reservation was previously used to treat and dispose of pyrophoric and water-reactive wastes contaminated with small quantities of radioactive materials (almost exclusively uranium and uranium daughters) from processes at the Department of Energy-owned, Oak Ridge Y-12 Plant and Oak Ridge National Laboratory. This paper describes remediation techniques utilizing a small, remotely operated submarine with an attached camera to visually locate waste containers, determine whether containers have been breached, transport small containers, and direct a larger remotely operated grappling machine to move larger waste for shredding operations. Most of the solid waste is reduced under water by a metal shredder. Non-shreddable items (e. g. , gas cylinders and larger structures) are mechanically breached under water to allow the contents to fully react. The waste is then removed from the water, monitored, the material is segregated, and transported to a temporary waste storage area until disposal.

  20. Maintaining competitiveness in a changing industry.

    PubMed

    1995-02-01

    The health care industry is undergoing a period of intense change. Mergers and acquisitions are common. Indemnity companies develop managed care divisions. HMOs develop PPO products. Hospitals form partnerships with medical groups. Unless government takes decisive action, (which appears unlikely), only the marketplace will eventually distinguish winners from losers. Meanwhile, these changes create anxiety for those of us trying to adapt to these changes. Change entails transition from the old to the new. Planning a smooth transition entails many decisions. Does it seem your management is always doing the wrong thing? Have you ever wondered if your own organization's actions are being sabotaged? Maybe they are. Maybe the following document is fiction, or maybe the author really did find it, crumpled and torn, behind the paper shredder. Because of the sensitive nature of the account, the author has asked for anonymity in return for supplying the story. PMID:10140220

  1. Earmarking? Yes

    NASA Astrophysics Data System (ADS)

    Schlossberg, Kenneth

    In recent years, the debate over congressional earmarking of funds for research facilities at universities has been characterized more by cliches than clear thinking. Opponents of the process quickly latched onto “Pork Barrel” as a way to condemn it, and proponents shot right back by labeling Peer Review the “Old Boys Network.” “Pork Barrel” usually refers to public works projects designed to generate political patronage. “Old Boys Network” is a way of describing business and country club connections that prevent outsiders from breaking into a lucrative economic circle. Neither has anything to do with a genuine national problem regarding the state of the nation's science research facilities or what should be done to resolve it, so I propose both cliches be sent to the shredder.

  2. Using clustering for document reconstruction

    NASA Astrophysics Data System (ADS)

    Ukovich, Anna; Zacchigna, Alessandra; Ramponi, Giovanni; Schoier, Gabriella

    2006-02-01

    In the forensics and investigative science fields there may arise the need of reconstructing documents which have been destroyed by means of a shredder. In a computer-based reconstruction, the pieces are described by numerical features, which represent the visual content of the strips. Usually, the pieces of different pages have been mixed. We propose an approach for the reconstruction which performs a first clustering on the strips to ease the successive matching, be it manual (with the help of a computer) or automatic. A number of features, extracted by means of image processing algorithms, have been selected for this aim. The results show the effectiveness of the features and of the proposed clustering algorithm.

  3. 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

  4. 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

  5. Evaluating the methane generation rate constant (k value) of low-organic waste at Danish landfills.

    PubMed

    Mou, Zishen; Scheutz, Charlotte; Kjeldsen, Peter

    2015-01-01

    The methane (CH4) generation rate constant (k value, yr(-1)) is an essential parameter when using first-order decay (FOD) landfill gas (LFG) generation models to estimate CH4 generation from landfills. Four categories of waste (street cleansing, mixed bulky, shredder, and sludge waste) with a low-organic content, as well as temporarily stored combustible waste, were sampled from four Danish landfills. Anaerobic degradation experiments were set up in duplicate for all waste samples and incubated for 405 days, while the cumulative CH4 generation was continuously monitored. Applying FOD equations to the experimental results, half-life time values (t½, yr) and k values of various waste categories were determined. In general, similar waste categories obtained from different Danish landfills showed similar results. Sludge waste had the highest k values, which were in the range 0.156-0.189 yr(-1). The combustible and street cleansing waste showed k values of 0.023-0.027 yr(-1) and 0.073-0.083 yr(-1), respectively. The lowest k values were obtained for mixed bulky and shredder wastes ranging from 0.013 to 0.017 yr(-1). Most low-organic waste samples showed lower k values in comparison to the default numeric values in current FOD models (e.g., IPCC, LandGEM, and Afvalzorg). Compared with the k values reported in the literature, this research determined low-organic waste for the first time via reliable large-scale and long-term experiments. The degradation parameters provided in this study are valuable when using FOD LFG generation models to estimate CH4 generation from modern landfills that receive only low-organic waste. PMID:25453319

  6. 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

  7. 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.

  8. 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

  9. 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

  10. Evaluating the biochemical methane potential (BMP) of low-organic waste at Danish landfills.

    PubMed

    Mou, Zishen; Scheutz, Charlotte; Kjeldsen, Peter

    2014-11-01

    The biochemical methane potential (BMP) is an essential parameter when using first order decay (FOD) landfill gas (LFG) generation models to estimate methane (CH4) generation from landfills. Different categories of waste (mixed, shredder and sludge waste) with a low-organic content and temporarily stored combustible waste were sampled from four Danish landfills. The waste was characterized in terms of physical characteristics (TS, VS, TC and TOC) and the BMP was analyzed in batch tests. The experiment was set up in triplicate, including blank and control tests. Waste samples were incubated at 55°C for more than 60 days, with continuous monitoring of the cumulative CH4 generation. Results showed that samples of mixed waste and shredder waste had similar BMP results, which was in the range of 5.4-9.1 kg CH4/ton waste (wet weight) on average. As a calculated consequence, their degradable organic carbon content (DOCC) was in the range of 0.44-0.70% of total weight (wet waste). Numeric values of both parameters were much lower than values of traditional municipal solid waste (MSW), as well as default numeric values in current FOD models. The sludge waste and temporarily stored combustible waste showed BMP values of 51.8-69.6 and 106.6-117.3 kg CH4/ton waste on average, respectively, and DOCC values of 3.84-5.12% and 7.96-8.74% of total weight. The same category of waste from different Danish landfills did not show significant variation. This research studied the BMP of Danish low-organic waste for the first time, which is important and valuable for using current FOD LFG generation models to estimate realistic CH4 emissions from modern landfills receiving low-organic waste. PMID:25106120

  11. 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

  12. 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. PMID:24810918

  13. 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

  14. 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

  15. 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.

  16. [Litter decomposition and associated macro-invertebrate functional feeding groups in a third-order stream of northern Guangdong].

    PubMed

    Yan, Ling; Zhao, Ying; Han, Cui-xiang; Tong, Xiao-li

    2007-11-01

    By placing 5 mm- and 0.1 mm mesh bags with Dracontomelon duperreanum (Anacardiaceae) and Syzygium jambos (Myrtaceae) litters in the Hengshishui Stream, a third-order stream in northern Guangdong of China, this paper studied the decomposition of the litters and the colonization of macro-invertebrates over a 101-day period. The results showed that the decomposition rate of D. duperreanum litter in 5 mm- and 0.1 mm mesh bags was 0.0247 d(-1) and 0.0151 d(-1), while that of S. jambos litter was 0.0108 d(-1) and 0.0095 d(-1), respectively, indicating that D. duperreanum litter decomposed faster than S. jambos litter, and the decomposition rates of these two kinds of litters were higher in coarse mesh bag than in fine mesh bag. Among the colonized macro-invertebrate functional feeding groups, scraper occupied the highest proportion (36%), followed by collector (33%), predator (25%), and shredder (6%). At the middle and late stages of the experiment, the total number of individuals and the numbers and densities of dominant groups of macroinvertebrates on D. duperreanum litter were significantly higher than those on S. jambos litter. It was suggested that in the subtropical medium-size streams where shredders are few or absent, scrapers play an important role in the breakdown of litter. The low decomposition rate of S. jambos litter was mainly due to its high content of polyphenols which inhibits microbial activity and makes the litter less eatable to the macro-invertebrates. PMID:18260466

  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. 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

  19. 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

  20. 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

  1. 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.

  2. 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

  3. 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

  4. 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

  5. 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.

  6. Liberation characteristics after cryogenic modification and air table separation of discarded printed circuit boards.

    PubMed

    Zhou, Cuihong; Pan, Yongtai; Lu, Maxi; Yang, Changshun

    2016-07-01

    Liberating useful materials from printed circuit boards (PCBs) is challenging because PCBs are flexible and complex in terms of materials and components. In this study, the crushing of PCBs at low-temperature was investigated. The results indicated that when the temperature was decreased to approximately -20 °C, the strength of PCBs decreased and their brittleness increased, making them easier to crush. A double roll crusher was selected to crush the PCBs. The particle size distribution and power consumption were studied under different working conditions. The results showed that the particle size of most of the lumps was in the range 15×20-25×20 mm, and that power consumption was minimal when the frequency of the crusher was 40-50 Hz. A small shredder was used for cryogenic grinding, and it was found that its power consumption strongly depended on the cooling temperature. An orthogonal experiment was conducted, which revealed that a smaller cutter gap and higher rotational speed could achieve higher yield. Furthermore, the results indicated that the air table developed to liberate PCB materials could effectively separate 2.8-0.5mm grade materials. Overall, the results of this study provide an experimental foundation for more effectively recycling discarded PCBs. PMID:26985873

  7. Automatized disassembly of electrical industrial motors

    NASA Astrophysics Data System (ADS)

    Karlsson, Bjoern; Fugger, Erwin

    1998-10-01

    Since February 1996 a large-scale European project called REMPRODUSE-Cu has been in progress. Its main objective is to provide a comprehensive approach to overcome the problems found when electromechanical systems reach the end of their useful life. How these problems could be overcome by a smarter recycling system and a smarter product design is in this project exemplified for electric motors. Today small electric motors when worn out are put in a shredder, due to problems with the disassembly. To be able to perform the disassembly in a proper way measurement and sensing as well as industrial robots will play an important part. In this paper a robotized work station for end-of-life treatment of industrial motors is presented. There are two main steps in the work. The first step is an inspection where the functionality of the motor is checked and the second step is robotized automatic disassembly for motors that can not be reused. This paper deals mainly with the second step. The robotized disassembly station consists of two industrial robots with appliances.

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

    PubMed

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

    1998-02-01

    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. PMID:9469853

  9. 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.

  10. 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

  11. Destruction and formation of dioxin-like PCBs in dedicated full scale waste incinerators.

    PubMed

    Van Caneghem, Jo; Block, Chantal; Vandecasteele, Carlo

    2014-01-01

    Destruction and formation of dioxin-like PCBs in full scale waste incinerators is studied by analysing input waste streams and boiler and fly ash of a grate furnace incinerator (GFI) incinerating MSW, of a Fluidised Bed Combustor (FBC) incinerating a mix of 50% sludge, 25% refuse derived fuel (RDF) and 25% automotive shredder residue (ASR) and of a rotary kiln incinerator (RKI) incinerating hazardous waste. The dioxin-like PCB fingerprints of the waste inputs show that PCB oils Aroclor 1242 and Aroclor 1254 late are the major dioxin-like PCB contamination source of sludge, RDF and ASR. The dioxin-like PCB fingerprints of the waste inputs are clearly different from the fingerprints of the outputs, i.e. boiler and fly ash, indicating that in full scale waste incinerators dioxin-like PCBs in the input waste are destroyed and other dioxin-like PCBs are newly formed in the post combustion zone. The dioxin-like PCB fingerprint of boiler and fly ash of all three incinerators corresponds well to the fly ash fingerprint obtained in lab scale de novo synthesis experiments, indicating that dioxin-like PCBs are mainly formed through this mechanism. The high PCB concentration in the input waste mix of the RKI does not promote the formation of dioxin-like PCBs through precursor condensation. PMID:24120013

  12. 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

  13. Waste washing pre-treatment of municipal and special waste.

    PubMed

    Cossu, Raffaello; Lai, Tiziana; Pivnenko, Kostyantyn

    2012-03-15

    Long-term pollution potential in landfills is mainly related to the quality of leachate. Waste can be conveniently treated prior to landfilling with an aim to minimizing future emissions. Washing of waste represents a feasible pre-treatment method focused on controlling the leachable fraction of residues and relevant impact. In this study, non-recyclable plastics originating from source segregation, mechanical-biological treated municipal solid waste (MSW), bottom ash from MSW incineration and automotive shredder residues (ASR) were treated and the removal efficiency of washing pre-treatment prior to landfilling was evaluated. Column tests were performed to simulate the behaviour of waste in landfill under aerobic and anaerobic conditions. The findings obtained revealed how waste washing treatment (WWT) allowed the leachability of contaminants from waste to be reduced. Removal rates exceeding 65% were obtained for dissolved organic carbon (DOC), chemical oxygen demand (COD) and Total Kjeldahl Nitrogen (TKN). A percentage decrease of approximately 60% was reached for the leachable fraction of chlorides, sulphates, fluoride and metals, as proved by a reduction in electric conductivity values (70%). PMID:21968117

  14. Improving the quality of waste-derived char by removing ash.

    PubMed

    Hwang, I H; Nakajima, D; Matsuto, T; Sugimoto, T

    2008-01-01

    This study characterized and removed ash from waste-derived char to improve the quality of char as fuel. Municipal solid waste (MSW) and automobile shredder residue (ASR) were carbonized at 450 degrees C and at 500 degrees C, respectively, in a rotary kiln with a nitrogen atmosphere for 1h. MSW and ASR char were subjected to sieving and pulverization-sieving to screen incombustibles and the ash-rich fraction, after which float-sink separation, froth floatation, and oil agglomeration were applied to remove ash from the char. The established target quality was (1) less than 30% ash content and (2) more than 20,000 kJ/kg heating value. However, the rate of combustibles recovery had to be lowered to produce a good quality of char along with a high heating value. MSW char attained the targeted quality level using froth floatation or oil agglomeration, whereas, neither separation method was able to make ASR-derived char satisfy the target. Based on the assumption that particle properties of char are determined by the weight ratio of combustibles and ash, the densities of combustibles and ash in char were estimated using the results of float-sink separation, X-ray diffraction (XRD) analysis, and elemental content. To verify the above assumption, an energy dispersive X-ray/scanning electron microscope (EDX/SEM) analyzer was used to observe char particles. PMID:17317141

  15. 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

  16. 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.

  17. 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

  18. Two-Year Comparison of a Stream Macroinvertebrate Functional Group Bioassessment Protocol for the Republic of Palau Archipelago

    NASA Astrophysics Data System (ADS)

    Olesen, A. A.; Benbow, M. E.; Holm, T.; Burky, A. J.

    2005-05-01

    Macroinvertebrate functional feeding group data was collected in 2003 and 2004 to develop a rapid bioassessment protocol for Palauan streams. One reference stream, Ngardmau, was selected to test functional group ratios and associated ecosystem attributes against streams of variable impact. In both years qualitative samples were collected using 30s dip net samples in pool habitats and benthic scouring methods in cascades with additional quantitative cascade collections for sampling technique comparisons in 2004. In the reference stream riffle habitat, filtering-gatherers dominated the community (89.92% in 2003 and 47.37% in 2004) compared to all other functional groups. Among the impacted streams, riffle functional group composition was variable compared to the reference stream. In reference pool habitats, gathering-collectors and scrapers dominated in 2003 and 2004, respectively. Scrapers dominated pool habitats of impacted streams in 2004, with some functional groups missing. Changes in ecosystem attributes followed functional group variability depending on degree of impact. Functional group ratios indicated channel stability ratio ([filtering-collectors + scrapers]/[shredders + gathering-collectors]) was lowered with increasing impact, suggesting food and/or habitat quality for filtering-collectors was degraded in riffle habitats in 2003 with no trends in 2004. By this protocol streams were determined to be degraded in 2004 relative to 2003.

  19. [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

  20. 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

  1. Enrichment of uranium in particulate matter during litter decomposition affected by Gammarus pulex L.

    PubMed

    Schaller, Jörg; Weiske, Arndt; Mkandawire, Martin; Dudel, E Gert

    2008-12-01

    Plant litter and organic matter of aquatic sediments provide a significant sink of soluble inorganic uranium species in contaminated ecosystems. The uranium content in detritus has been observed to increase significantly during decomposition. However, the influence of the decomposer community on uranium fixation remains unclear. In view of this, we investigated the influence of a shredder (the freshwater shrimp Gammarus pulex L) on uranium fixation and mobilization during the degradation of plant litter. Leaf litter from Alnus glutinosa (L.) Gaertn. with 1152 mg kg(-1) U of dry biomass (DM) and without uranium was used in a 14-day laboratory experiment. The uranium concentration in the particulate organic material (POM) at the end of experiment was 1427 mg kg(-1) DM. After 14 days of decay, the residues of the leaves show a uranium concentration of 644 mg kg(-1) DM. Uranium concentrations in the media initially increased reaching up to 63.9 microg L(-1) but finally decreased to an average value of 34.3 microg L(-1). Atthe same time, DOC levels increased from 2.43 mg L(-1) up to 11.4 mg L(-1) in the course of the experiment Hence, inorganic uranium fixation onto particulate organic matter was enhanced by the activity of G. pulex. PMID:19192788

  2. [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. PMID:22919851

  3. 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.

  4. Jointly sponsored research program. Quarterly technical progress report, April--June, 1994

    SciTech Connect

    Not Available

    1994-10-01

    Objectives, accomplishments, procedures, and results are briefly described for each of the following 18 research projects: 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 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 and interpretation of naturally and artificially matured kerogens; CROW{trademark} field demonstration with bell lumber and pole; ``B`` series pilot plant tests; In situ treatment of manufactured gas plant contaminated soils demonstration program; Development and demonstration of a wood-fired gas turbine system; NMR analysis of Mowry Formation shale from different sedimentary basins; and Acid-mine drainage prevention, control, and treatment technology development for the Stockett/Sand Coulee Area.

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

    SciTech Connect

    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.

  6. 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.

  7. The Effects of Urbanization on the Food Web of a Mid-order Stream in Rio de Janeiro, Brazil

    NASA Astrophysics Data System (ADS)

    Detweiler, A. M.; Hershey, A. E.; Moulton, T. P.; Brito, E. F.

    2005-05-01

    Stream degradation caused by point source and non-point source pollution, loss of riparian vegetation, erosion and sedimentation can alter aquatic food webs. Due to the lack of proper sewage treatment, the main polluter in urban streams of Brazil is raw sewage. The purpose of this study is to determine if sewage-derived carbon and nitrogen are incorporated into the aquatic system and how this may affect the food web. We collected food web components at four sites along an urban stream, Rio Paineiras, and a reference stream, Rio Andorinha. Samples were analyzed for natural abundance of 13C and 15N. Raw sewage signatures were distinct and enriched compared to primary sources. Riparian vegetation and CPOM samples became significantly more enriched in 15N along the urban stream, compared to the reference stream. Periphyton 15N and 13C signatures were not significantly different between streams. Fish (Astyanax hastatus and Poecilids) showed some incorporation of sewage-derived 13C and 15N, in distinct trophic groups. Macroinvertebrate Hetaerina sp. reflected some incorporation of sewage-derived 15N. We also observed a reduction in functional feeding groups in the sewage-influenced reach of Rio Paineiras. Collectors, gatherers, and shredders were absent as stream degradation increased. Downstream communities were composed mostly of fish.

  8. 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.

  9. Percentage of Impervious Surface Soil as Indicator of Urbanization Impacts in Neotropical Aquatic Insects.

    PubMed

    Fogaça, F N O; Gomes, L C; Higuti, J

    2013-10-01

    Several recent studies have shown a strong correlation between the area of impervious surface soil (IS) and the insect community structure from urban streams. This study assessed whether this relationship is observed in Neotropical streams. We examined if an increased IS reduces the diversity and simplifies the trophic structure of the community of Ephemeroptera, Plecoptera, and Trichoptera. An IS threshold was detected between 1.6 and 9.3%, in which there is a change in the community, both in taxonomic richness and trophic structure. Among the 27 genera identified, only 15 occurred in streams with IS > 9%, while 24 genera were registered in streams with IS < 2%. The trophic guilds of predators and shredders were not observed in streams with high IS, decreasing the number of guilds in these streams from 5 to 3, compared with the streams with low IS. Three hypotheses with cumulative effect have been proposed to explain such variations. Based on the IS threshold verified, the creation of a mosaic of land use, where some subbasins would be sacrificed and others would be preserved, was suggested as a mitigation measure for the impacts caused by urbanization in the Neotropical aquatic insects' fauna. PMID:23949987

  10. 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.

  11. 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

  12. The Utility of Decomposition and Associated Microbial Parameters to Assess Changes in Stream Ecosystems due to Eutrophication

    NASA Astrophysics Data System (ADS)

    Gulis, V.; Ferreira, V. J.; Graca, M. A.

    2005-05-01

    Traditional approaches to assess stream ecosystem health rely on structural parameters, e.g. a variety of biotic indices. The goal of the Europe-wide RivFunction project is to develop methodology that uses functional parameters (e.g. plant litter decomposition) to this end. Here we report on decomposition experiments carried out in Portugal in five pairs of streams that differed in dissolved inorganic nutrients. On average, decomposition rates of alder and oak leaves were 2.8 and 1.4 times higher in high nutrient streams in coarse and fine mesh bags, respectively, than in corresponding reference streams. Breakdown rate correlated better with stream water SRP concentration rather than TIN. Fungal biomass and sporulation rates of aquatic hyphomycetes associated with decomposing leaves were stimulated by higher nutrient levels. Both fungal parameters measured at very early stages of decomposition (e.g. days 7-13) correlated well with overall decomposition rates. Eutrophication had no significant effect on shredder abundances in leaf bags but species richness was higher in disturbed streams. Decomposition is a key functional parameter in streams integrating many other variables and can be useful in assessing stream ecosystem health. We also argue that because decomposition is often controlled by fungal activity, microbial parameters can also be useful in bioassessment.

  13. Does the current fungicide risk assessment provide sufficient protection for key drivers in aquatic ecosystem functioning?

    PubMed

    Zubrod, Jochen P; Englert, Dominic; Feckler, Alexander; Koksharova, Natalia; Konschak, Marco; Bundschuh, Rebecca; Schnetzer, Nadja; Englert, Katja; Schulz, Ralf; Bundschuh, Mirco

    2015-01-20

    The level of protection provided by the present environmental risk assessment (ERA) of fungicides in the European Union for fungi is unknown. Therefore, we assessed the structural and functional implications of five fungicides with different modes of action (azoxystrobin, carbendazim, cyprodinil, quinoxyfen, and tebuconazole) individually and in mixture on communities of aquatic hyphomycetes. This is a polyphyletic group of fungi containing key drivers in the breakdown of leaf litter, governing both microbial leaf decomposition and the palatability of leaves for leaf-shredding macroinvertebrates. All fungicides impaired leaf palatability to the leaf-shredder Gammarus fossarum and caused structural changes in fungal communities. In addition, all compounds except for quinoxyfen altered microbial leaf decomposition. Our results suggest that the European Union’s first-tier ERA provides sufficient protection for the tested fungicides, with the exception of tebuconazole and the mixture, while higher-tier ERA does not provide an adequate level of protection for fungicides in general. Therefore, our results show the need to incorporate aquatic fungi as well as their functions into ERA testing schemes to safeguard the integrity of aquatic ecosystems. PMID:25517729

  14. 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

  15. 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

  16. 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

  17. 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.

  18. 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 20min at 144°C without a pre-mixing/fragmenting step. In a 720L steam treatment system including pre-mixing/fragmenting paddles, only 10min at 144°C are required to sterilize IHCW proved to be sterilization challenges such as dialysis cartridges and diapers in normal conditions of rolling. PMID:26803472

  19. 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. PMID:26000755

  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. PMID:21828352

  1. Rolling tires into rubber

    SciTech Connect

    Malloy, M.G.

    1997-06-01

    For Envirotire (Lillington, North Carolina), producing quality crumb rubber this summer is all in a night`s work. The tire recycling facility has operated in Lillington, which is about an hour south of Raleigh, North Carolina, for about a year and a half, since October 1995. In the summer, the plant runs at night to save money in electricity costs by operating during off-peak hours; in the winter, daytime hours also can be off-peak. In contrast to the cryogenic systems used elsewhere to recycle tires, Envirotire`s system works on mechanical principles. Before the tires are even shredded, a worker cuts the white-walls out of the tires manually, so the white does not contaminate the black end-product. A worker places the tires manually on a conveyor, which feed them up to an initial shredder that sections them quickly into pieces. While the tires are on the conveyor, dividing strips on the conveyor mark off a place for each tire. The system takes nine new tires per minute.

  2. 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. PMID:25945636

  3. Proteomic characterization of the major arthropod associates of the carnivorous pitcher plant Sarracenia purpurea.

    PubMed

    Gotelli, Nicholas J; Smith, Aidan M; Ellison, Aaron M; Ballif, Bryan A

    2011-06-01

    The array of biomolecules generated by a functioning ecosystem represents both a potential resource for sustainable harvest and a potential indicator of ecosystem health and function. The cupped leaves of the carnivorous pitcher plant, Sarracenia purpurea, harbor a dynamic food web of aquatic invertebrates in a fully functional miniature ecosystem. The energetic base of this food web consists of insect prey, which is shredded by aquatic invertebrates and decomposed by microbes. Biomolecules and metabolites produced by this food web are actively exchanged with the photosynthesizing plant. In this report, we provide the first proteomic characterization of the sacrophagid fly (Fletcherimyia fletcheri), the pitcher plant mosquito (Wyeomyia smithii), and the pitcher-plant midge (Metriocnemus knabi). These three arthropods act as predators, filter feeders, and shredders at distinct trophic levels within the S. purpurea food web. More than 50 proteins from each species were identified, ten of which were predominantly or uniquely found in one species. Furthermore, 19 peptides unique to one of the three species were identified using an assembled database of 100 metazoan myosin heavy chain orthologs. These molecular signatures may be useful in species monitoring within heterogeneous ecosystem biomass and may also serve as indicators of ecosystem state. PMID:21538880

  4. Proteomic Characterization of the Major Arthropod Associates of the Carnivorous Pitcher Plant Sarracenia purpurea

    PubMed Central

    Gotelli, Nicholas J.; Smith, Aidan M.; Ellison, Aaron M.; Ballif, Bryan A.

    2012-01-01

    The array of biomolecules generated by a functioning ecosystem represents both a potential resource for sustainable harvest and a potential indicator of ecosystem health and function. The cupped leaves of the carnivorous pitcher plant, Sarracenia purpurea, harbor a dynamic food web of aquatic invertebrates in a fully functional miniature ecosystem. The energetic base of this food web consists of insect prey, which is shredded by aquatic invertebrates and decomposed by microbes. Biomolecules and metabolites produced by this food web are actively exchanged with the photosynthesizing plant. In this report, we provide the first proteomic characterization of the sacrophagid fly (Fletcherimyia fletcheri), the pitcher plant mosquito (Wyeomyia smithii), and the pitcher-plant midge (Metriocnemus knabi). These three arthropods act as predators, filter feeders, and shredders at distinct trophic levels within the S. purpurea food web. More than 50 proteins from each species were identified, 10 of which were predominantly or uniquely found in one species. Furthermore, 19 peptides unique to one of the three species were identified using an assembled database of 100 metazoan myosin heavy chain orthologs. These molecular signatures may be useful in species monitoring within heterogeneous ecosystem biomass and may also serve as indicators of ecosystem state. PMID:21538880

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. 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. PMID:20599249

  10. 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.

  11. Cryofracture as a tool for preprocessing retrieved buried and stored transuranic waste

    SciTech Connect

    Loomis, G.G.; Winberg, M.R.; Ancho, M.L. ); Osborne, D. )

    1992-01-01

    This paper summarizes important features of an experimental demonstration of applying the Cryofracture process to size-reduce retrieved buried and stored transuranic-contaminated wastes. By size reducing retrieved buried and stored waste, treatment technologies such as thermal treatment can be expedited. Additionally, size reduction of the waste can decrease the amount of storage space required by reducing the volume requirements of storage containers. A demonstration program was performed at the Cryofracture facility by Nuclear Remedial Technologies for the Idaho National Engineering Laboratory. Cryofracture is a size-reducing process whereby objects are frozen to liquid nitrogen temperatures and crushed in a large hydraulic press. Material s at cryogenic temperatures have low ductility and are easily size-reduced by fracturing. Six 55-gallon drums and six 2 {times} 2 {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.

  12. Cryofracture as a tool for preprocessing retrieved buried and stored transuranic waste

    SciTech Connect

    Loomis, G.G.; Winberg, M.R.; Ancho, M.L.; Osborne, D.

    1992-08-01

    This paper summarizes important features of an experimental demonstration of applying the Cryofracture process to size-reduce retrieved buried and stored transuranic-contaminated wastes. By size reducing retrieved buried and stored waste, treatment technologies such as thermal treatment can be expedited. Additionally, size reduction of the waste can decrease the amount of storage space required by reducing the volume requirements of storage containers. A demonstration program was performed at the Cryofracture facility by Nuclear Remedial Technologies for the Idaho National Engineering Laboratory. Cryofracture is a size-reducing process whereby objects are frozen to liquid nitrogen temperatures and crushed in a large hydraulic press. Material s at cryogenic temperatures have low ductility and are easily size-reduced by fracturing. Six 55-gallon drums and six 2 {times} 2 {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.

  13. 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

  14. 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.

  15. Impact of different particle size distributions on anaerobic digestion of the organic fraction of municipal solid waste.

    PubMed

    Zhang, Y; Banks, C J

    2013-02-01

    Particle size may significantly affect the speed and stability of anaerobic digestion, and matching the choice of particle size reduction equipment to digester type can thus determine the success or failure of the process. In the current research the organic fraction of municipal solid waste was processed using a combination of a shear shredder, rotary cutter and wet macerator to produce streams with different particle size distributions. The pre-processed waste was used in trials in semi-continuous 'wet' and 'dry' digesters at organic loading rate (OLR) up to 6kg volatile solids (VS) m(-3)day(-1). The results indicated that while difference in the particle size distribution did not change the specific biogas yield, the digester performance was affected. In the 'dry' digesters the finer particle size led to acidification and ultimately to process failure at the highest OLR. In 'wet' digestion a fine particle size led to severe foaming and the process could not be operated above 5kgVSm(-3)day(-1). Although the trial was not designed as a direct comparison between 'wet' and 'dry' digestion, the specific biogas yield of the 'dry' digesters was 90% of that produced by 'wet' digesters fed on the same waste at the same OLR. PMID:23167994

  16. Relationships Between Litter Processing and Impervious Surface Cover in Headwater Tributaries of the St. Johns River, Florida

    NASA Astrophysics Data System (ADS)

    Chadwick, M. A.; Dobberfuhl, D. R.; Benke, A. C.; Huryn, A. D.; Suberkropp, K.; Thiele, J. E.

    2005-05-01

    We investigated relationships between land-use and litter processing in 18 tributaries of the St. Johns River, Florida. The percent total impervious area (PTIA) of these catchments ranged from 0-66%. We measured mass loss and fungal biomass (as ergosterol) and associated macroinvertebrate biomass for 2 litter species (red maple [Acer rubrum] and sweetgum [Liquidambar styraciflua]). Processing rates ranged from 0.010-0.046d-1 for maple and 0.006-0.018d-1 for sweetgum. The fastest processing occurred at intermediate PTIA. Fungal biomass peaked at 24 days with the lowest biomass occurring in the low PTIA stream. Rates of processing were positively related to both mean macroinvertebrate biomass and taxa richness. Shredder biomass was not related to maple, but was negatively related to sweetgum processing. Scraper biomass peaked at intermediate PTIA, and was positively related to processing rates for both leaf species. We reduced correlated physicochemical, land-use and biological variables to several orthogonal variables using principle components analysis. Regression models based on these variables accounted for 70% of the variance in processing rates for both leaf species. Collectively, these results demonstrate that PTIA and other land-use indicators are associated with differences in stream ecosystem patterns and processes between low gradient, subtropical streams.

  17. Performance of a full-scale biofilter with peat and ash as a medium for treating industrial landfill leachate: a 3-year study of pollutant removal efficiency.

    PubMed

    Kängsepp, Pille; Mathiasson, Lennart

    2009-03-01

    Shredder residues of end-of-life vehicles and white goods are a complex waste stream, which nowadays most often is disposed of at industrial landfills. This paper describes the most important findings concerning the complex composition of the landfill leachate and its on-site, year-round treatment under cold-climate conditions. A 3-year investigation has confirmed that concentrations of different types of pollutants, most of them at low initial concentrations, can be simultaneously reduced in vertical-flow biofilters consisting of a mixture of peat and carbon-containing ash. For metals such as Mn, Cu, Sn, Cd, Pb, Fe and Ni the average removal was 73, 72, 66, 60, 55, 55 and 37%, respectively. An average reduction of NH(4)-N (45%), N(tot) (25%), total organic carbon (30%), dissolved organic carbon (28%) and suspended solids (38%) was also obtained. A good reduction was achieved for phenols (between 75 and 95%), polychlorinated biphenyls (between 22 and 99%), and gas chromatography-mass spectrometry amenable pollutants, considered at initial concentration above 50 microg L( -1) (between 80 and 100%). The performance of the biofilter system was good in spite of large variations of inlet concentration during the considered period. PMID:19244414

  18. Effects of wildfire on aquatic invertebrates in British Columbia streams

    NASA Astrophysics Data System (ADS)

    Heise, B. A.

    2005-05-01

    I examined the effects of the 2003 McClure fire on aquatic invertebrates in three forested streams. Two sites were sampled on Fishtrap Creek, which was extensively burned, one site was sampled on Peterson Creek, which was patchily burned, and one site sampled on Jamieson Creek, which served as the unburned control. The intensely burned areas of Fishtrap Creek had all vegetation removed around the creek, and burned the ground to the mineral soil. Random Hess samples were taken in riffles in all creeks in April 2004. Densities of mayflies, stoneflies, caddisflies and diptera varied significantly among the creeks, and were lower in the burned streams compared to the control. The lower site on Fishtrap Creek, which flowed through the most intensely burned area, had a mean of only 67 individuals per square meter, compared to a mean of 1823 in the control. As expected due to the loss of riparian vegetation, shredder densities (Nemouridae+ Leuctridae+Capniidae) were significantly reduced in the burned streams (p=0.008).

  19. Experimental investigation of sedimentation of LOCA - generated fibrous debris and sludge in BWR suppression pools

    SciTech Connect

    Souto, F.J.; Rao, D.V.

    1995-12-01

    Several tests were conducted in a 1:2.4 scale model of a Mark I suppression pool to investigate the behavior of fibrous insulation and sludge debris under LOCA conditions. NUKON{trademark} shreds, manually cut and tore up in a leaf shredder, and iron oxide particles were used to simulate fibrous and sludge debris, respectively. The suppression pool model included four downcomers fitted with pistons to simulate the steam-water oscillations during chugging expected during a LOCA. The study was conducted to provide debris settling velocity data for the models used in the BLOCKAGE computer code, developed to estimate the ECCS pump head loss due to clogging of the strainers with LOCA generated debris. The tests showed that the debris, both fibrous and particulate, remains fully mixed during chugging; they also showed that, during chugging, the fibrous debris underwent fragmentation into smaller sizes, including individual fibers. Measured concentrations showed that fibrous debris settled slower than the sludge, and that the settling behavior of each material is independent of the presence of the other material. Finally, these tests showed that the assumption of considering uniform debris concentration during strainer calculations is reasonable. The tests did not consider the effects of the operation of the ECCS on the transport of debris in the suppression pool.

  20. 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.

  1. A process to recover plastics from obsolete automobiles by using solvents at ambient pressure

    SciTech Connect

    Jody, B.J.; Daniels, E.J.; Bonsignore, P.V.; Brockmeier, N.F.

    1993-08-01

    Recycling of the metal content of obsolete vehicles has been actively pursued since the 1950s; today, obsolete automobiles are the single largest source of scrap iron. They contribute over 25% of the 36 metric tonnes (40 million short tons) of ferrous scrap recovered annually by the secondary metals industry and used in the production of finished steel products. They also contribute over one million metric tonnes (1.1 million short tons) of nonferrous metallic scrap a year for recycling. For each ton of metals recovered, about 500 lb of nonmetallic residue or waste is co-produced. Auto shredder residue (ASR) is a very heterogeneous mixture of solids and liquids. Table I lists most of the materials that are commonly present in the ASR are listed. We have developed and tested in the laboratory a three-step process to separate thermoplastics, and other potentially recyclable products, from ASR. The process involves a drying step followed by a mechanical separation step to concentrate the thermoplastics by separating the polyurethane foam and the fines, which are mostly metal oxides and other inert materials that are smaller than 0.62 cm (0.25 in.) in size. The concentrated plastics stream is then treated with organic solvents at ambient pressure and elevated temperatures to dissolve the desired plastics. The salient features of the process are described.

  2. 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.

  3. Dade County Resources Recovery Facility

    SciTech Connect

    Strong, C.R.; Portuondo, J. )

    1988-01-01

    The Dade County Resources Recovery Facility was built for the county and operated by Parsons and Whittemore from 1981 to 1985. It was permitted to process 920,000 tons per year of MSW. Trash was processed into RDF through a two shredder dry system and garbage through a wet process hydrosposal system producing 50% moisture RDF. The RDF was burned in four water tube boilers to produce superheated steam to drive 2-38.5 MW turbine generators. FP and L purchased the generated electricity. The plant ran at 18,000 tons/Wk. for a short time. By early 1985, the plant was in disrepair, the wet process had caused serious equipment erosion and corrosion, especially in the boilers and the wet process had created serious regulatory and public pressure due to odors and emissions. P and W was removed by the county in June 1985 and replaced by Montenay Power Corp. as plant operator. Mountenay has developed and presented to the county a rehabilitation plan to get the plant back to capacity by 1990. The wet process was shutdown in September 1986.

  4. Power generation opportunities for emerging waste conversion technologies

    SciTech Connect

    Anderson, C.M.; Ness, R.O. Jr.; Swanson, M.L.; Mann, M.D.

    1995-12-31

    Increasing quantities of wastes and more stringent disposal regulations combined with the public`s desire to see integrated waste management strategies have created an atmosphere of opportunity. A number of processes are being developed by the Energy and Environmental Research Center (EERC) that offer solutions to the burgeoning waste problem. In the area of solid waste processing, municipal solid wastes have been carbonized and converted into a benign, high quality slurry fuel. Pelletizing and briquetting activities have produced high-quality solid fuels. Extensive efforts have been undertaken in market development for recycled materials, specializing in tertiary recycling of plastics. The issues facing systems for the conversion of opportunity fuels to energy have been addressed for both the combustion and gasification mode, using such diverse fuels as sewage sludge, wood chips, automotive shredder residue, and sunflower hulls. Conversion of biomass to direct-use fuels has also been an ongoing concern and a major focus of the EERC. The focus of this paper will be the identification of methods for converting wastes into valuable fuels or other ``products`` and how they can be used to enhance power generation options.

  5. Evaluation and test program of a 50-ton-per-day Lantz converter. Second quarterly technical progress report

    SciTech Connect

    Not Available

    1983-04-01

    The evaluation and test program of a 50-ton-per-day Lantz converter pyrolysis process for producing pyrolytic gas from municipal solid waste was begun in September 1982 at the Marcal Paper Mills plant in Elmwood Park, New Jersey. The Lantz converter, the drier, shredder, moving floor, conveyer, char ram, boiler and other auxiliary equipment were installed and tested by the Lantz America group in a specially constructed building on the Marcal site. During the past three months the plant has been run almost every day, originally using waste paper as the feed stock and then switching to municipal solid waste. Some unexpected technical difficulties were encountered especially with the control system of the Cleaver Brooks boiler and as of this date all of the steam produced in the boiler has just been vented to the atmosphere. Thus the overall operation of the plant is still being debugged and the plant has not been run for periods of more than a few hours at a time. Hopefully a series of sustained, long time runs will be initiated next month so that both meaningful test data can be taken and the steam produced from the pyrolytic gas can be sold to Marcal.

  6. 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.

  7. 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

  8. 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

  9. 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.

  10. PCB decomposition and formation in thermal treatment plant equipment.

    PubMed

    Ishikawa, Yukari; Noma, Yukio; Yamamoto, Takashi; Mori, Yoshihito; Sakai, Shin-ichi

    2007-04-01

    In this study we investigated both the decomposition and unintentional formation of polychlorinated biphenyl congeners during combustion experiments of refuse-derived fuel (RDF) and automobile shredder residue (ASR) at several stages in thermal treatment plant equipment composed of a primary combustion chamber, a secondary combustion chamber, and other equipments for flue gas treatment. In both experiments, the unintentional formation of PCB occurred in the primary combustion chamber at the same time as the decomposition of PCB in input samples. By combusting RDF, non-ortho-PCB predominantly formed, whereas ortho-PCB and symmetric chlorinated biphenyls (e.g., #52/69, #87/108, and #151) tended to be decomposed. ASR formed the higher chlorinated biphenyls more than RDF. These by-products from ASR had no structural relation with ortho-chlorine. Lower chlorinated biphenyls appeared as predominant homologues at the final exit site, while all congeners from lower to higher chlorinated PCB were unintentionally formed as by-products in the primary combustion chamber. This result showed that the flue gas treatment equipments effectively removed higher chlorinated PCB. Input marker congeners of RDF were #11, #39, and #68, while those for ASR were #11, #101, #110/120, and #118. Otherwise, combustion marker congeners of RDF were #13/12, #35, #77, and #126, while those for ASR were #170, #194, #206, and #209. While the concentration of PCB increased significantly in the primary combustion chamber, the value of toxicity equivalency quantity for dioxin-like PCB decreased in the secondary combustion chamber and the flue gas treatment equipments. PMID:17134732

  11. A statewide outbreak of Salmonella bovismorbificans phage type 32 infection in Queensland.

    PubMed

    Stafford, Russell J; McCall, Bradley J; Neill, Annette S; Leon, Dallas S; Dorricott, Gregory J; Towner, Christopher D; Micalizzi, Gino R

    2002-01-01

    Between 30 May and 1 June 2001, 10 cases of Salmonella Bovismorbificans infection were reported to Public Health Services, Queensland Health. Investigations included enhanced surveillance, case interviews, a matched case control study, environmental audit and microbiological testing of faecal isolates (phage typing) and implicated food products. Forty-one cases of S. Bovismorbificans infection were detected, 36 cases were phage type 32. A matched case control study identified that illness was associated with consumption of food from 15 outlets of a fast food chain, Company A (matched odds ratio [MOR] 17.5, 95% CI 2.0-657.3, p = 0.004) and consumption of a particular product, Product X (MOR undefined, p < 0.001) in the week before onset of illness. Manufacturers of Product X ingredients were audited. Deficiencies were identified in equipment cleansing at the salad mixture processing plant (Manufacturer M). A swab of food residue behind the cutting wheel rim of the lettuce shredder was positive for S. Bovismorbificans phage type 32. This appears to be the first reported Australian outbreak of salmonellosis associated with a lettuce product. The investigations suggest that inadequate maintenance of cutting equipment to prepare lettuce ingredients for Product X by Manufacturer M was a key factor in this statewide outbreak. The statewide nature of this outbreak demonstrates the role of timely serovar identification of Salmonella isolates by a reference laboratory as an aid to outbreak identification, and the importance of adherence to appropriate food safety procedures in the manufacture and preparation of mass produced food items for the public. PMID:12549525

  12. 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.

  13. 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

  14. Rapid degradation of phenol by ultrasound-dispersed nano-metallic particles (NMPs) in the presence of hydrogen peroxide: A possible mechanism for phenol degradation in water.

    PubMed

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

    2016-06-15

    The present study was carried out to investigate the degradation of phenol by ultrasonically dispersed nano-metallic particles (NMPs) in an aqueous solution of phenol. Leaching liquor from automobile shredder residue (ASR) was used to obtain the NMPs. The prepared NMPs were analyzed by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and by X-ray diffraction (XRD). The SEM images show that the diameters of the NMPs were less than 50 nm. An SEM-EDX elemental analysis reveals that Fe was the most commonly found element (weight %) in the NMPs. The FTIR and XRD peaks indicate the presence of metals oxides on the surfaces of the NMPs. The results of the XPS analysis indicate that various elements (e.g., C, O, Zn, Cu, Mn, Fe) are present on the surfaces of the NMPs. The effects of the NMP dose, the initial solution pH, and of different concentrations of phenol and H2O2 on the phenol degradation characteristics were evaluated. The results of this study demonstrate that phenol degradation can be improved by increasing the amount of NMPs, whereas it is reduced with an increase in the phenol concentration. The degradation of phenol by ultrasonically dispersed NMPs followed the pseudo-first-order kinetics. The probable mechanism of phenol degradation by ultrasonically dispersed NMPs was the oxidation of phenol caused by the hydroxyl radicals produced during the reaction between H2O2 and the NMPs during the ultrasonication process. PMID:27038433

  15. 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

  16. 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

  17. 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. PMID:26068228

  18. 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.

  19. 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.

  20. 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

  1. 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

  2. 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.

  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. Hydrogenous Gas Production through Reactions among Supercritical Water, Ironmaking Sludge, and Steelmaking Slag and Recycling of Wastes from Integrated Steel Mills

    NASA Astrophysics Data System (ADS)

    Hayashi, Shoji

    Automobile Shredder Residue (ASR) and Refuse derived fuels (not carbonized and carbonized: YRDF and RDF) as carbonaceous wastes were reacted isothermally with sub-supercritical water (600-695°C, 200 atm) together with a CO2 fixation reagent Ca(OH)2 inside a closed metallic tube reactor (7cm3). Product gas mainly consisted of hydrogen gas and a little methane gas except YRDF. As a whole, gas generated more in order ASR, YRDF, and RDF. Addition of catalysis NaOH or KOH made product gas increase more. KOH was more effective to product gas than NaOH. X-ray diffraction followed that Ca(OH)2 and CaCO3 existed mainly in residues after reaction tests with a CO2 fixation reagent Ca(OH)2 or CaO. Therefore, it was supposed that an overall chemical reaction took place as shown below. BOF steelmaking slag for CO2 fixation provided maximum gas generation 1.42 times as much as molar carbon in a RDF sample with KOH. C + H2O + Ca(OH)2 = CaCO3 + 2H2 Two kinds of wastes from integrated steel mills (sludge from mill scale and activated sludge) were each reacted with supercritical water (600-650°C, 200 atm). Both sludges were effective to generate hydrogenous gas. It was found that harmful cyan in the latter sludge mostly decomposed after reaction. Also, the crushing strength after curing the steelmaking slag bearing residue briquette was not as high as that from Portland cement.

  5. 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

  6. Eutrophication downstream from small reservoirs in mountain rivers of Central Spain.

    PubMed

    Camargo, Julio A; Alonso, Alvaro; de la Puente, Marcos

    2005-09-01

    In this research we examined the hypothesis that upper reaches of rivers and streams can experience eutrophication as a consequence of deep releases from dams. Field studies were conducted in four mountain rivers (Tormes, Riaza, Eresma and Miraflores Rivers) of Central Spain. The watersheds of these rivers are underlain by siliceous rocks. A small deep-release storage reservoir is found in the upper reaches of each river. Two sampling sites, upstream and downstream from the reservoir, were established in stony riffles of each impounded river. Significant (P < 0.01) increases in conductivity and nutrient (NO3-N, NH4-N, PO4-P) concentrations downstream from the reservoirs were measured. Significant (P < 0.01) increases in periphyton chlorophyll a and ash-free dry biomass were also quantified at downstream sites. Significant (P < 0.01) correlation coefficients indicated that phosphate would play a more important role as the limiting nutrient for periphyton. Relative abundances of macroinvertebrate scrapers and collector-gatherers increased downstream from the reservoirs. Furthermore, taxon dominance, total density and total biomass of macroinvertebrates tended to be higher at downstream sites than at upstream sites. In contrast, taxon diversity and relative abundance of macroinvertebrate shredders decreased downstream from the reservoirs. It is concluded that small deep-release storage reservoirs, located in upper reaches of siliceous rivers, can act as nutrient sources, causing eutrophication downstream. Nutrients would ultimately come from land/forest runoff. The fact that terrestrial vegetation was not completely removed before filling reservoirs could also contribute to the eutrophication process. PMID:16039693

  7. 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.

  8. 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.

  9. Performance evaluation of intermediate cover soil barrier for removal of heavy metals in landfill leachate.

    PubMed

    Suzuki, Kazuyuki; Anegawa, Aya; Endo, Kazuto; Yamada, Masato; Ono, Yusaku; Ono, Yoshiro

    2008-11-01

    This pilot-scale study evaluated the use of intermediate cover soil barriers for removing heavy metals in leachate generated from test cells for co-disposed fly ash from municipal solid waste incinerators, ash melting plants, and shredder residue. Cover soil barriers were mixtures of Andisol (volcanic ash soil), waste iron powder, (grinder dust waste from iron foundries), and slag fragments. The cover soil barriers were installed in the test cells' bottom layer. Sorption/desorption is an important process in cover soil bottom barrier for removal of heavy metals in landfill leachate. Salt concentrations such as those of Na, K, and Ca in leachate were extremely high (often greater than 30 gL(-1)) because of high salt content in fly ash from ash melting plants. Concentrations of all heavy metals (nickel, manganese, copper, zinc, lead, and cadmium) in test cell leachates with a cover soil barrier were lower than those of the test cell without a cover soil barrier and were mostly below the discharge limit, probably because of dilution caused by the amount of leachate and heavy metal removal by the cover soil barrier. The cover soil barriers' heavy metal removal efficiency was calculated. About 50% of copper, nickel, and manganese were removed. About 20% of the zinc and boron were removed, but lead and cadmium were removed only slightly. Based on results of calculation of the Langelier saturation index and analyses of core samples, the reactivity of the cover soil barrier apparently decreases because of calcium carbonate precipitation on the cover soil barriers' surfaces. PMID:18842283

  10. 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

  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. 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.

  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. 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. PMID:20022623

  15. 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

  16. 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

  17. 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

  18. 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).

  19. The development and prospects of the end-of-life vehicle recycling system in Taiwan.

    PubMed

    Chen, Kuan-chung; Huang, Shih-han; Lian, I-wei

    2010-01-01

    Automobiles usually contain toxic substances, such as lubricants, acid solutions and coolants. Therefore, inappropriate handling of end-of-life vehicles (ELVs) will result in environmental pollution. ELV parts, which include metallic and non-metallic substances, are increasingly gaining recycling value due to the recent global shortage of raw materials. Hence, the establishment of a proper recycling system for ELVs will not only reduce the impact on the environment during the recycling process, but it will also facilitate the effective reuse of recycled resources. Prior to 1994, the recycling of ELVs in Taiwan was performed by related operators in the industry. Since the publishing of the "End-of-life vehicle recycling guidelines" under the authority of the Waste Disposal Act by the Environmental Protection Administration (EPA) in 1994, the recycling of ELVs in Taiwan has gradually become systematic. Subsequently, the Recycling Fund Management Board (RFMB) of the EPA was established in 1998 to collect a Collection-Disposal-Treatment Fee (recycling fee) from responsible enterprises for recycling and related tasks. Since then, the recycling channels, processing equipment, and techniques for ELVs in Taiwan have gradually become established. This paper reviews the establishment of the ELV recycling system, analyzes the current system and its performance, and provides some recommendations for future development. The reduction of auto shredder residue (ASR) is a key factor in maximizing the resource recovery rate and recycling efficiency. The RFMB needs to provide strong economic incentives to further increase the recycling rate and to encourage the automobile industry to design and market greener cars. PMID:20382516

  20. Effects of pre-treatment technologies on quantity and quality of source-sorted municipal organic waste for biogas recovery.

    PubMed

    Hansen, Trine Lund; Jansen, Jes la Cour; Davidsson, Asa; Christensen, Thomas Højlund

    2007-01-01

    Source-sorted municipal organic waste collected from different dwelling types in five Danish cities and pre-treated at three different plants was sampled and characterized several times during one year to investigate the origin of any differences in composition of the pre-treated waste introduced by city, pre-treatment technology, dwelling type or annual season. The investigated pre-treatment technologies were screw press, disc screen and shredder+magnet. The average quantity of pre-treated organic waste (biomass) produced from the incoming waste varied between the investigated pre-treatment technologies: 59%, 66% and 98% wet weight, respectively (41%, 34% and 2% reject, respectively). The pre-treatment technologies showed differences with respect to distribution of the chemical components in the waste between the biomass and the rejected material (reject), especially for dry matter, ash, collection bag material (plastic or paper) and easily degradable organic matter. Furthermore, the particle size of the biomass was related to the pre-treatment technology. The content of plastic in the biomass depended both on the actual collection bag material used in the system and the pre-treatment technology. The sampled reject consisted mostly of organic matter. For cities using plastic bags for the source-separated organic waste, the expected content of plastic in the reject was up to 10% wet weight (in some cases up to 20%). Batch tests for methane potential of the biomass samples showed only minor variations caused by the factors city, pre-treatment technology, dwelling type and season when based on the VS content of the waste (overall average 459STPm(3)/tVS). The amount of methane generated from 1t of collected waste was therefore mainly determined by the efficiency of the chosen pre-treatment technology described by the mass distribution of the incoming waste between biomass and reject. PMID:16678397

  1. 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

  2. Destroying LLW and hazardous waste on-site with the synthetica steam detoxifier

    SciTech Connect

    Galloway, T.R.; Depetris, S.S.

    1994-12-31

    The amount of hazardous waste and low level waste generated in the country is growing at a steady rate, yet the options for effectively dealing with these waste streams are becoming fewer and fewer. In this paper we discuss a new technology that holds considerable promise for dealing with LLW and hazardous waste. The Synthetica{reg_sign} Detoxifier (STD) does not use air combustion and has no flame - quite different from incineration. It carries out hazardous waste destruction by very high temperature steam reforming (i.e., 2000 to 2700{degrees}F), and is only 4 ft x 6 ft x 7.5 ft in size. Vent gases are carbon dioxide and water. Destruction and removal efficiencies (DREs) exceed 99.99% for even the most refractory organics. The capacity is from 2 to 5 drums per day, or a ton per day, depending on the type of waste being processed. The STD combined with a Heated Shredder Evaporator feed system has shown considerable success reducing the mass and volume of low level waste (up to 50 fold reduction). A list of some of the many waste streams that have been processed with the STD are presented. The STD, with its low-risk operation, small size and the fact that it is not an incinerator greatly simplifies siting and permitting in today`s environment. User advantages are that it eliminates risky transportation of hazardous and low-level wastes and terminates their liability with their generated waste for a fixed cost. Costs are less than half that for incineration of landfilling.

  3. Report: landfill alternative daily cover: conserving air space and reducing landfill operating cost.

    PubMed

    Haughey, R D

    2001-02-01

    Title 40, Part 258 of the Code of Federal Regulations, Solid Waste Disposal Facility Criteria, commonly referred to as Subtitle D, became effective on October 9, 1993. It establishes minimum criteria for solid waste disposal facility siting, design, operations, groundwater monitoring and corrective action, and closure and postclosure maintenance, while providing EPA-approved state solid waste regulatory programs flexibility in implementing the criteria. Section 258.21(a) [40 CFR 258.21(a)] requires owners or operators of municipal solid waste landfill (MSWLF) units to cover disposed solid waste with 30cm of earthen material at the end of the operating day, or at more frequent intervals, if necessary, to control disease vectors, fires, odours, blowing litter, and scavenging. This requirement is consistent with already existing solid waste facility regulations in many states. For many MSWLFs, applying daily cover requires the importation of soil which increases landfill operating costs. Daily cover also uses valuable landfill air space, reducing potential operating revenue and the landfill's operating life. 40 CFR 258.21 (b) allows the director of an approved state to approve alternative materials of an alternative thickness if the owner or operator demonstrates that the alternative material and thickness will control disease vectors, fires, odours, blowing litter, and scavenging without presenting a threat to human health and the environment. Many different types of alternative daily cover (ADC) are currently being used, including geosynthetic tarps, foams, garden waste, and auto shredder fluff. These materials use less air space than soil and can reduce operating costs. This paper discusses the variety of ADCs currently being used around the country and their applicability to different climates and operating conditions, highlighting the more unusual types of ADC, the types of demonstrations necessary to obtain approval of ADC, and the impact on landfill air space

  4. 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.

  5. 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.

  6. Relative importance of bacteria and fungi in a tropical headwater stream: leaf decomposition and invertebrate feeding preference.

    PubMed

    Wright, M S; Covich, A P

    2005-05-01

    Bacteria and fungi provide critical links between leaf detritus and higher trophic levels in forested headwater food webs, but these links in tropical streams are not well understood. We compared the roles of bacteria and fungi in the leaf decomposition process and determining feeding preference for two species of freshwater shrimp found in the Luquillo Experimental Forest, Puerto Rico, using experimental microcosms. We first tested the effects of four treatments on decomposition rates for leaves from two common riparian species, Cecropia scheberiana (Moraceae) and Dacryodes excelsa (Burseraceae), in laboratory microcosms. Treatments were designed to alter the microbial community by minimizing the presence of bacteria or fungi. The fastest decay rate was the control treatment for D. excelsa where both bacteria and fungi were present (k = -0.0073 day(-1)) compared to the next fastest rate of k = -0.0063 day(-1) for the bacterial-conditioned D. excelsa leaves. The fastest decay rate for C. scheberiana was also the control treatment (k = -0.0035 day(-1)), while the next fastest rate was for fungal-conditioned leaves (k = -0.0029 day(-1)). The nonadditive effect for leaf decomposition rates observed in the control treatments where both fungi and bacteria were present indicate that bacteria and fungi perform different functions in processing leaf litter. Additionally, leaf types differed in microbial colonization patterns. We next tested feeding preference for leaf type and microbe treatment in microcosms using two species of freshwater shrimp: Xiphocaris elongata, a shredder, and Atya lanipes, a scraper/filterer. To estimate feeding preferences of individual shrimp, we measured change in leaf surface area and the amount of particles generated during 5-day trials in 16 different two-choice combinations. X. elongata preferred D. excelsa over C. scheberiana, and leaves with microbial conditioning over leaves without conditioning. There was no clear preference for fungal

  7. 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

  8. 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

  9. 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

  10. Leaf litter quality affects aquatic insect emergence: contrasting patterns from two foundation trees.

    PubMed

    Compson, Zacchaeus G; Adams, Kenneth J; Edwards, Joeseph A; Maestas, Jesse M; Whitham, Thomas G; Marks, Jane C

    2013-10-01

    Reciprocal subsidies between rivers and terrestrial habitats are common where terrestrial leaf litter provides energy to aquatic invertebrates while emerging aquatic insects provide energy to terrestrial predators (e.g., birds, lizards, spiders). We examined how aquatic insect emergence changed seasonally with litter from two foundation riparian trees, whose litter often dominates riparian streams of the southwestern United States: Fremont (Populus fremontii) and narrowleaf (Populus angustifolia) cottonwood. P. fremontii litter is fast-decomposing and lower in defensive phytochemicals (i.e., condensed tannins, lignin) relative to P. angustifolia. We experimentally manipulated leaf litter from these two species by placing them in leaf enclosures with emergence traps attached in order to determine how leaf type influenced insect emergence. Contrary to our initial predictions, we found that packs with slow-decomposing leaves tended to support more emergent insects relative to packs with fast-decomposing leaves. Three findings emerged. Firstly, abundance (number of emerging insects m(-2) day(-1)) was 25% higher on narrowleaf compared to Fremont leaves for the spring but did not differ in the fall, demonstrating that leaf quality from two dominant trees of the same genus yielded different emergence patterns and that these patterns changed seasonally. Secondly, functional feeding groups of emerging insects differed between treatments and seasons. Specifically, in the spring collector-gatherer abundance and biomass were higher on narrowleaf leaves, whereas collector-filterer abundance and biomass were higher on Fremont leaves. Shredder abundance and biomass were higher on narrowleaf leaves in the fall. Thirdly, diversity (Shannon's H') was higher on Fremont leaves in the spring, but no differences were found in the fall, showing that fast-decomposing leaves can support a more diverse, complex emergent insect assemblage during certain times of the year. Collectively, these

  11. BioCoComb -- Gasification of biomass and co-combustion of the gas in a pulverized-coal-boiler

    SciTech Connect

    Anderl, H.; Zotter, T.; Mory, A.

    1999-07-01

    In a demonstration project supported by an European Community Thermie Fund a biomass gasifier for bark, wood chips, saw dust, etc. has been installed by Austrian Energy and Environment at the 137 MW{sub el} pulverized-coal fired power station in Zeltweg, Austria. The project title BioCoComb is an abbreviation for Preparation of Biofuel for Co-Combustion, where co-combustion means combustion together with coal in existing power plants. According to the thermal capacity of 10 MW the produced gas substitutes approx. 3% of the coal fired in the boiler. Only the coarse fraction of the biomass has to pass a shredder and is then fed together with the fine fraction without any further pretreatment into the gasifier. In the gasification process the biomass will combust in a substoichiometric atmosphere, create the necessary temperature of 820 C and partly gasify due to the lack of oxygen in the combustion chamber (autothermal operation). The gasifier uses circulating fluidized bed technology, which guarantees even relatively low temperatures in all parts of the gasifier to prevent slagging. The intense motion of the bed material also favors attrition of the biomass particles. Via a hot gas duct the produced low calorific value (LCV) gas is directly led into the furnace of the existing pulverized coal fired boiler for combustion. The gas also contains fine wood char particles, that can pass the retention cyclone and burn out in the furnace of the coal boiler. The main advantages of the BioCoComb concept are: low gas quality sufficient for co-firing; no gas cleaning or cooling; no predrying of the biomass; relatively low temperatures in the gasifier to prevent slagging; favorable effects on power plant emissions (CO{sub 2}, NO{sub x}); no severe modifications of the existing coal fired boiler; and high flexibility in arranging and integrating the main components into existing plants. The plant started its trial run in November 1997 and has been in successful commercial

  12. 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

  13. 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

  14. Metal-bearing Aerosols of Industrial Origin from Multiple Sources in South Phoenix, Arizona: Separating Similar Particle Types with Minor Element Differences Using Automated SEM Analysis of Large Populations of Particles

    NASA Astrophysics Data System (ADS)

    Anderson, J.; Hua, X.

    2009-12-01

    Particulate pollution, especially PM10, in the Greater Phoenix (Maricopa County) airshed is a long-standing problem. While much of the PM10 can be ascribed to soil dust entrained by human activity (e.g., sand and gravel mining and other construction-support activities both directly and indirectly), south-central and southwest Phoenix have a significant number of industrial sources of metal-bearing particles. Many of these particles are dominated compositionally by Fe but have minor elements such as Cu, Ba, Mn, Cr, Ni and others which can be statistically mutually exclusive when large populations are looked at with automated Scanning Electron Microscopy (SEM). Bulk aerosol chemical analysis of high-volume samples shows the presence of these elements, including the dominance of Fe at times, but there are far more potential sources than can ever by deduced by principal component analysis of the bulk sample data. Because of the potential toxic nature of these industrial particles, about which there is considerable community concern, identifying the multiple sources is a key step in mitigating the pollution. Also present in these industrial aerosols are mostly submicron particles containing Sr, Sb, V, Cd, and other elements in various combinations. While analyzing the minor element content of submicron particles, some of which are beam-sensitive, pushes the limits of automated SEM techniques, this is the only way to examine large, statistically significant particle populations in many samples on an individual-particle basis. The elemental associations in these unusual metal-bearing particles tend to be the key to source identification. Particle morphology is also important in separating particle types from different sources in these populations. For instance, one of major sources of Fe-dominant particles in southwest Phoenix is a scrap metal operation that uses a “mega-shredder”. This mega-shredder generates enough heat to melt some of the metal and produce roughly

  15. 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.