WorldWideScience

Sample records for as recycling process

  1. Continental moisture recycling as a Poisson process

    Directory of Open Access Journals (Sweden)

    H. F. Goessling

    2013-04-01

    Full Text Available On their journey across large land masses, water molecules experience a number of precipitation-evaporation cycles (recycling events. We derive analytically the frequency distributions of recycling events for the water molecules contained in a given air parcel. Given the validity of certain simplifying assumptions, continental moisture recycling is shown to develop either into a Poisson distribution or a geometric distribution. We distinguish two cases: in case (A recycling events are counted since the water molecules were last advected across the ocean-land boundary. In case (B recycling events are counted since the water molecules were last evaporated from the ocean. For case B we show by means of a simple scale analysis that, given the conditions on Earth, realistic frequency distributions may be regarded as a mixture of a Poisson distribution and a geometric distribution. By contrast, in case A the Poisson distribution generally appears as a reasonable approximation. This conclusion is consistent with the simulation results of an earlier study where an atmospheric general circulation model equipped with water vapor tracers was used. Our results demonstrate that continental moisture recycling can be interpreted as a Poisson process.

  2. Continental moisture recycling as a Poisson process

    OpenAIRE

    2013-01-01

    On their journey across large land masses, water molecules experience a number of precipitation-evaporation cycles (recycling events). We derive analytically the frequency distributions of recycling events for the water molecules contained in a given air parcel. Given the validity of certain simplifying assumptions, continental moisture recycling is shown to develop either into a Poisson distribution or a geometric distribution. We distinguish two cases: in case (A) recycling events a...

  3. Continental moisture recycling as a Poisson process

    OpenAIRE

    2013-01-01

    On their journey over large land masses, water molecules experience a number of precipitation–evaporation cycles (recycling events). We derive analytically the frequency distributions of recycling events for the water molecules contained in a given air parcel. Given the validity of certain simplifying assumptions, the frequency distribution of recycling events is shown to develop either into a Poisson distribution or a geometric distribution. We distingu...

  4. The siderulgical process as way of recycling plastic residues

    Directory of Open Access Journals (Sweden)

    M.A. Diez

    2012-06-01

    Full Text Available The development of new recycling ways to allow therecovery of plastics from municipal wastes is of greatinterest in order to keep as many options open,especially when the co-processing with raw materialscan be performed in consolidate industrial processes.In this context, integrated steel plants can beconsidered as an option for those wastes withtechnical limitations for conventional mechanicalrecycling. The combination of the blast furnace routeand coke plant in the steel industry provide a wayto expand feedstock recycling with severalenvironmental benefits such as saving fossil fuels,reducing landfill of the wastes and reducing solidparticles, SO2 and CO2 emissions. This paper is anattempt to compile some relevant advances in theserecycling routes.

  5. The proof of the pudding: urban recycling in North America as a process of ecological modernisation.

    NARCIS (Netherlands)

    Scheinberg, A.

    2003-01-01

    This essay analyses the history of the development of municipal recycling in the United States between 1970 and 1996 as a case of Ecological Modernisation. Using the framework of Ecological Modernisation Theory (EMT), the essay examines the predecessor institutions to modern recycling, showing how e

  6. Comminution and sizing processes of concrete block waste as recycled aggregates.

    Science.gov (United States)

    Gomes, P C C; Ulsen, C; Pereira, F A; Quattrone, M; Angulo, S C

    2015-11-01

    Due to the environmental impact of construction and demolition waste (CDW), recycling is mandatory. It is also important that recycled concrete aggregates (RCA) are used in concrete to meet market demands. In the literature, the influence of RCAs on concrete has been investigated, but very limited studies have been conducted on how the origin of concrete waste and comminution processes influence RCA characteristics. This paper aims to investigate the influence of three different comminution and sizing processes (simple screening, crushing and grinding) on the composition, shape and porosity characteristics of RCA obtained from concrete block waste. Crushing and grinding implies a reduction of RCA porosity. However, due to the presence of coarse quartz rounded river pebbles in the original concrete block mixtures, the shape characteristics deteriorated. A large amount of powder (<0.15 mm) without detectable anhydrous cement was also generated.

  7. Development of tailored ceramic microstructures using recycled marble processing residue as pore-former

    Science.gov (United States)

    Domopoulou, A.; Spiliotis, X.; Charalampides, G.; Baklavaridis, A.; Papapolymerou, G.; Karayannis, V.

    2016-06-01

    Recycling of marble processing residue is significant since marble processing constitutes an important industrial sector. Therefore, the sustainable management and the valorisation, in an economically profitable manner, of this industrial by-product should be considered. In this work, the potential use of marble residue as pore-former into clayey mixtures for the production of lightweight, porous and thermal insulating ceramics is investigated. Four samples consisting of clayey ceramic body incorporating up to 50 wt.% fine marble residue powder were produced. The final ceramic products were produced upon firing (sintering) at 950oC. Porosity and thermal conductivity measurements were carried out in order to assess the thermal insulating behavior of the produced sintered ceramics. The porosity of the sintered ceramics increases substantially by increasing the marble residue admixture loading. This, in turn, leads to a decrease in thermal conductivity. Consequently, the marble residue can be successfully employed as pore-forming agent, in order to improve the insulating behavior of the ceramic materials.

  8. CHALLENGES FOR PROCESS INDUSTRIES IN RECYCLING

    Institute of Scientific and Technical Information of China (English)

    Lothar Reh

    2006-01-01

    Increasing population and individual wealth have led to a higher demand for energy and raw material resources as well as for steady improvement of processing technology in view of efficient use of resources and avoiding emissions in production and recycling processes. Present situation and future trend of recycling processing are discussed by examples from the aluminium and steel industries, recycling of cars and post-consumer municipal recovery.The importance of more intense observance of thermodynamic laws and of a 4E strategy "Economy, Energy, Environment and Education" is outlined.

  9. Survey of metallurgical recycling processes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Pemsler, J.P.

    1979-03-01

    In the year 2000, the US will consume about 3.2 x 10/sup 15/ Btu to produce the seven major nonferrous metals Al, Cu, Zn, Pb, Ni, Mg, and Ti. Of this amount, 82% will be used in the production of Al. It is projected that 0.6 x 10/sup 15/ Btu will be saved by the recycle of secondary metals. Major opportunities for increasing the extent of recycle and thereby increasing the energy savings are discussed. An inherent feature in the energistics of recycle is that physical processes such as magnetic separation, density separations, melting, and in some instances vaporization are far less energy intensive than are chemical processes associated with dissolution and electrowinning. It is in the domain of scrap of complex composition and physical form, difficult to handle by existing technology, that opportunities exist for new chemical recycle technology. Recycle of scrap metal of adequate grade is currently achieved through pyrometallurgical processes which, in many cases, are not very energy intensive as compared with hydrometallurgical processes. Preliminary flowsheets are presented for the recovery of value metals from batteries considered for use in vehicular propulsion and load leveling applications. The battery types examined are lead/acid, nickel/zinc, nickel/iron, zinc/chlorine, lithium-aluminum/iron sulfide, and sodium/sulfur. A flow sheet has been outlined for an integrated hydrometallurgical process to treat low-grade copper scrap. A fully integrated hydrometallurgical process is outlined, and costs and energy consumption are derived, for recovering zinc metal from electric furnace flue dusts. Costs and energy are high and the process does not appear to warrant development at this time. Improvement in the recycle of magnesium is associated primarily with improved recycle in the Al industry where Mg is an important alloy additive. Ni and Ti recycle are associated with improved collection and sorting of stainless steel and specialty alloys.

  10. Recycling as moral behaviour

    DEFF Research Database (Denmark)

    Thøgersen, John

    of Reasoned Action (TRA) with regard to understanding recycling behaviour. Further, examples of misleading policy conclusions are discussed suggested that within the framework of cognitive psychology, Schwartz's model of altruistic behaviour offers a more satisfying starting point for understanding recycling...... of the balance of costs and benefits. Rather, they are a function of the person's moral beliefs, i.e., beliefs in what is the right or wrong thing to do. The paper gives a brief review of the literature with the intention of uncovering problems and shortcomings in the framework of the SEU-model and the Theory...

  11. Scientific Opinion on the safety evaluation of the process “INTERSEROH Step 1” used to recycle polypropylene cratesfor use as food contact material

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2012-10-01

    Full Text Available

    The EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF provides a scientific opinion dealing with the safety evaluation of the recycling process “INTERSEROH Step 1” with the EC register number RECYC069. The process recycles pre-washed damaged food contact re-usable polypropylene crates (RPC which have been used in a closed and controlled product loop into new recycled polypropylene crates. Through this process, cleaned damaged crates are firstly ground into flakes, which are further blended with virgin polypropylene (PP or used up to 100% to manufacture new recycled crates. The Panel considered that repeated grinding and injection moulding of PP crates which is part of the recycling process, under conditions described by the applicant, is not of safety concern. The Panel concluded that the input of the process “INTERSEROH Step 1” originates from a product loop which is in a closed and controlled chain designed to ensure that only materials and articles which have been intended for food contact are used and that any contamination can be ruled out when run under the conditions described by the applicant. The recycling process “INTERSEROH Step 1” is therefore able to produce recycled PP suitable for manufacturing PP crates intended to be used in contact with whole fruits and vegetables as requested by the applicant.

  12. The Role of Sub- and Supercritical CO2 asProcessing Solvent” for the Recycling and Sample Preparation of Lithium Ion Battery Electrolytes

    Directory of Open Access Journals (Sweden)

    Sascha Nowak

    2017-03-01

    Full Text Available Quantitative electrolyte extraction from lithium ion batteries (LIB is of great interest for recycling processes. Following the generally valid EU legal guidelines for the recycling of batteries, 50 wt % of a LIB cell has to be recovered, which cannot be achieved without the electrolyte; hence, the electrolyte represents a target component for the recycling of LIBs. Additionally, fluoride or fluorinated compounds, as inevitably present in LIB electrolytes, can hamper or even damage recycling processes in industry and have to be removed from the solid LIB parts, as well. Finally, extraction is a necessary tool for LIB electrolyte aging analysis as well as for post-mortem investigations in general, because a qualitative overview can already be achieved after a few minutes of extraction for well-aged, apparently “dry” LIB cells, where the electrolyte is deeply penetrated or even gellified in the solid battery materials.

  13. CHARACTERIZATION AND PROCESSING OF SCALES FROM THE MECHANICAL DESCALING OF CARBON STEELS FOR RECYCLING AS COATING PIGMENTS

    Directory of Open Access Journals (Sweden)

    Anderson de Oliveira Fraga

    2014-10-01

    Full Text Available The large volume of solid wastes generated as scales in Steel Mills accounts to circa 1% to 2% of the total steel production and has led to studies aiming the recycling of scales, usually resulting in products of low added value. In this study, scales from the mechanical descaling of SAE 1045 steel were characterized by SEM and by quantitative X-Ray diffraction (Rietveld method, as well as by differential thermal analysis, aiming to develop its pretreatment for the further use as lamellar pigments in anticorrosive coatings of high added value. Aspect ratios between 1:50 and 1:100 were obtained by the processing of scales, which allows the replacement of other micaceous iron oxides.

  14. Claus recycle with double combustion process

    Energy Technology Data Exchange (ETDEWEB)

    El-Bishtawi, Ribhi; Haimour, No' man [University of Jordan, Amman 11942 (Jordan)

    2004-12-15

    A new modification is developed on conventional Claus process to increase the overall sulfur recovery as well as to decrease the costs. The modification combines both oxygen enrichment and recycling. The process is simulated and studied for various N{sub 2}/O{sub 2} ratios with and without using SURE double combustion technique. The predictions show that using pure oxygen in combustion, condensing water vapor in a condenser following the first sulfur condenser and recycling the effluent gas to combine it with fresh acid gas feed leads to large savings in the production cost and to a clean environment. However, it leads to a high adiabatic flame temperature which exceeds the maximum allowable temperature of the furnace material of construction as well as its refractory. To avoid these effects, it is necessary to use SURE double combustion technique. The oxygen flow rate to the first combustion stage should not exceed 78% O{sub 2}.

  15. Scrap tyre recycling process with molten zinc as direct heat transfer and solids separation fluid: A new reactor concept.

    Science.gov (United States)

    Riedewald, Frank; Goode, Kieran; Sexton, Aidan; Sousa-Gallagher, Maria J

    2016-01-01

    Every year about 1.5 billion tyres are discarded worldwide representing a large amount of solid waste, but also a largely untapped source of raw materials. The objective of the method was to prove the concept of a novel scrap tyre recycling process which uses molten zinc as the direct heat transfer fluid and, simultaneously, uses this media to separate the solids products (i.e. steel and rCB) in a sink-float separation at an operating temperature of 450-470 °C. This methodology involved: •construction of the laboratory scale batch reactor,•separation of floating rCB from the zinc,•recovery of the steel from the bottom of the reactor following pyrolysis.

  16. Processing solid propellants for recycling

    Energy Technology Data Exchange (ETDEWEB)

    Whinnery, L.L.; Griffiths, S.K.; Handrock, J.L.; Lipkin, J.

    1994-05-01

    Rapid evolution in the structure of military forces worldwide is resulting in the retirement of numerous weapon systems. Many of these systems include rocket motors containing highly energetic propellants based on hazardous nitrocellulose/nitroglycerin (NC/NG) mixtures. Even as the surplus quantities of such material increases, however, current disposal methods -- principally open burning and open detonation (OB/OD) -- are coming under close scrutiny from environmental regulators. Environmentally conscious alternatives to disposal of propellant and explosives are thus receiving renewed interest. Recycle and reuse alternatives to OB/OD appear particularly attractive because some of the energetic materials in the inventories of surplus weapon systems represent potentially valuable resources to the commercial explosives and chemical industries. The ability to reclaim such resources is therefore likely to be a key requirement of any successful technology of the future in rocket motor demilitarization. This document consists of view graphs from the poster session.

  17. A biotechnological process for treatment and recycling poultry wastes manure as a feed ingredient

    Energy Technology Data Exchange (ETDEWEB)

    El Jalil, M.H. [Faculty of Sciences, Kenitra (Morocco). Biology Dept.; Hassan II Inst. of Agronomy and Veterinary Medicine, Rabat-Instituts (Morocco); Faid, M. [Hassan II Inst. of Agronomy and Veterinary Medicine, Rabat-Instituts (Morocco); Elyachioui, M. [Faculty of Sciences, Kenitra (Morocco)

    2001-07-01

    Poultry wastes manure was diluted by adding the same amount of water 50-50 (w/v). They were then mixed with 10% molasses. The mixture was inoculated with a starter culture of Lactobacillus plantarum and Pediococcus acidolactici, and incubated at 30{sup o}C for 10 days. Changes in nutritional quality and biochemical properties (pH, total nitrogen, total volatile nitrogen, non protein nitrogen, carbohydrates and ash) were determined for the raw and the transformed product. In parallel, microbiological analyses, including standard plant count, enterobacteria and enterococci, were performed. Results indicated that the product obtained from the wastes fermentation showed low counts of enterobacteria and enterococci. Chemical determinations showed a net decrease of the pH to around 4.0 and the growth curve of the lactic acid bacteria showed the success of the acidification process. The total nitrogen was conserved in the product and the total volatile nitrogen was totally eliminated. The product was used for substituting some protein sources in a conventional formula used in laying feeding of three lots. Two formulae containing, respectively, 20% and 40% of the product was compared to the control (0%). The food consumption and laying performances were monitored for 30 days. The nutritional test indicted that the incorporation of the poultry manure silage of up to 40% gave laying performances similar to those obtained with the conventional formula. These results show that it is possible to transform poultry manure by controlled fermentation and that the product has an added value as a feed ingredient. (Author)

  18. Flows of engineered nanomaterials through the recycling process in Switzerland

    Energy Technology Data Exchange (ETDEWEB)

    Caballero-Guzman, Alejandro; Sun, Tianyin; Nowack, Bernd, E-mail: nowack@empa.ch

    2015-02-15

    Highlights: • Recycling is one of the likely end-of-life fates of nanoproducts. • We assessed the material flows of four nanomaterials in the Swiss recycling system. • After recycling, most nanomaterials will flow to landfills or incineration plants. • Recycled construction waste, plastics and textiles may contain nanomaterials. - Abstract: The use of engineered nanomaterials (ENMs) in diverse applications has increased during the last years and this will likely continue in the near future. As the number of applications increase, more and more waste with nanomaterials will be generated. A portion of this waste will enter the recycling system, for example, in electronic products, textiles and construction materials. The fate of these materials during and after the waste management and recycling operations is poorly understood. The aim of this work is to model the flows of nano-TiO{sub 2}, nano-ZnO, nano-Ag and CNT in the recycling system in Switzerland. The basis for this study is published information on the ENMs flows on the Swiss system. We developed a method to assess their flow after recycling. To incorporate the uncertainties inherent to the limited information available, we applied a probabilistic material flow analysis approach. The results show that the recycling processes does not result in significant further propagation of nanomaterials into new products. Instead, the largest proportion will flow as waste that can subsequently be properly handled in incineration plants or landfills. Smaller fractions of ENMs will be eliminated or end up in materials that are sent abroad to undergo further recovery processes. Only a reduced amount of ENMs will flow back to the productive process of the economy in a limited number of sectors. Overall, the results suggest that risk assessment during recycling should focus on occupational exposure, release of ENMs in landfills and incineration plants, and toxicity assessment in a small number of recycled inputs.

  19. Direction of CRT waste glass processing: electronics recycling industry communication.

    Science.gov (United States)

    Mueller, Julia R; Boehm, Michael W; Drummond, Charles

    2012-08-01

    Cathode Ray Tube, CRT, waste glass recycling has plagued glass manufacturers, electronics recyclers and electronics waste policy makers for decades because the total supply of waste glass exceeds demand, and the formulations of CRT glass are ill suited for most reuse options. The solutions are to separate the undesirable components (e.g. lead oxide) in the waste and create demand for new products. Achieving this is no simple feat, however, as there are many obstacles: limited knowledge of waste glass composition; limited automation in the recycling process; transportation of recycled material; and a weak and underdeveloped market. Thus one of the main goals of this paper is to advise electronic glass recyclers on how to best manage a diverse supply of glass waste and successfully market to end users. Further, this paper offers future directions for academic and industry research. To develop the recommendations offered here, a combination of approaches were used: (1) a thorough study of historic trends in CRT glass chemistry; (2) bulk glass collection and analysis of cullet from a large-scale glass recycler; (3) conversations with industry members and a review of potential applications; and (4) evaluation of the economic viability of specific uses for recycled CRT glass. If academia and industry can solve these problems (for example by creating a database of composition organized by manufacturer and glass source) then the reuse of CRT glass can be increased.

  20. Scientific Opinion on the safety evaluation of the process “INTERSEROH Step 2” used to recycle polypropylene crates for use as food contact material

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2013-07-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the recycling process “INTERSEROH Step 2”, EU register number RECYC070. The process recycles pre-washed damaged food contact re-usable polypropylene crates (RPC or parts of crates which have been used in a closed and controlled product loop into new recycled crates. Through this process, pre-washed damaged RPC and parts of crates are ground into flakes. The flakes are compounded, extruded into pellets then used up to 100 % for the production of new recycled PP crates by injection moulding. The Panel considered that repeated grinding and injection moulding of PP crates which is part of the recycling process, under conditions described by the applicant, is not of safety concern. The Panel concluded that the input of the process “INTERSEROH Step 2” originates from a product loop which is in a closed and controlled chain designed to ensure that only materials and articles which have been intended for food contact are used and that any contamination can be ruled out when run under the conditions described by the applicant. The recycling process “INTERSEROH Step 2” is therefore able to produce recycled PP suitable for manufacturing PP crates intended to be used in contact with whole fruits and vegetables at room temperature or below.

  1. Scientific Opinion on the safety evaluation of the process “CO.N.I.P.” used to recycle polypropylene and polyethylene crates for use as food contact material

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2013-04-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the recycling process “CO.N.I.P.”, EC register number RECYC040. The process recycles single use food contact polypropylene (PP and high-density polyethylene (HDPE crates which have been used in a closed and controlled product loop into new recycled crates. Through this process, single use crates are firstly ground into flakes which may be used as such or further processed by extrusion or densification into granules. Recycled flakes or granules are used with or without blending with PP or HDPE offcuts or scrap to manufacture new recycled PP and HDPE crates by injection moulding. The Panel concluded that the input of the process “CO.N.I.P.” originates from a product loop which is in a closed and controlled chain ensuring that only materials and articles which have been intended for food contact are used and that any contamination can be ruled out when run under the conditions described by the applicant. The recycling process “CO.N.I.P.” is therefore able to produce recycled PP and HDPE suitable for manufacturing PP and HDPE crates intended to be used in contact with whole fruits and vegetables at room temperature or below as requested by the applicant.

  2. Scientific Opinion on the safety evaluation of the process “Schoeller Arca Systems”, used to recycle polypropylene and high-density polyethylene crates for use as food contact material

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2013-04-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the recycling process “Schoeller Arca Systems”, EC register number RECYC075. The process recycles damaged food contact re-usable polypropylene (PP and high-density polyethylene (HDPE crates which have been used in a closed and controlled product loop into new recycled crates. Through this process, damaged crates are firstly ground into flakes which are further blended with virgin PP or HDPE or used at 100 % to manufacture new recycled PP and HDPE crates. The CEF Panel concluded that the input of the process “Schoeller Arca Systems” originates from a product loop which is in a closed and controlled chain ensuring that only materials and articles which have been intended for food contact are used and that any contamination can be ruled out when run under the conditions described by the applicant. The Panel considered that the repeated grinding and injection moulding of PP and HDPE crates, which is part of the recycling process, under conditions described by the applicant, is not of safety concern. Therefore the recycling process “Schoeller Arca Systems” is able to produce recycled PP and HDPE suitable for manufacturing crates intended to be used in contact at room temperature or below with meat, whole fruits and vegetables as requested by the applicant.

  3. Supercritical Water Process for the Chemical Recycling of Waste Plastics

    Science.gov (United States)

    Goto, Motonobu

    2010-11-01

    The development of chemical recycling of waste plastics by decomposition reactions in sub- and supercritical water is reviewed. Decomposition reactions proceed rapidly and selectively using supercritical fluids compared to conventional processes. Condensation polymerization plastics such as PET, nylon, and polyurethane, are relatively easily depolymerized to their monomers in supercritical water. The monomer components are recovered in high yield. Addition polymerization plastics such as phenol resin, epoxy resin, and polyethylene, are also decomposed to monomer components with or without catalysts. Recycling process of fiber reinforced plastics has been studied. Pilot scale or commercial scale plants have been developed and are operating with sub- and supercritical fluids.

  4. Flows of engineered nanomaterials through the recycling process in Switzerland.

    Science.gov (United States)

    Caballero-Guzman, Alejandro; Sun, Tianyin; Nowack, Bernd

    2015-02-01

    The use of engineered nanomaterials (ENMs) in diverse applications has increased during the last years and this will likely continue in the near future. As the number of applications increase, more and more waste with nanomaterials will be generated. A portion of this waste will enter the recycling system, for example, in electronic products, textiles and construction materials. The fate of these materials during and after the waste management and recycling operations is poorly understood. The aim of this work is to model the flows of nano-TiO2, nano-ZnO, nano-Ag and CNT in the recycling system in Switzerland. The basis for this study is published information on the ENMs flows on the Swiss system. We developed a method to assess their flow after recycling. To incorporate the uncertainties inherent to the limited information available, we applied a probabilistic material flow analysis approach. The results show that the recycling processes does not result in significant further propagation of nanomaterials into new products. Instead, the largest proportion will flow as waste that can subsequently be properly handled in incineration plants or landfills. Smaller fractions of ENMs will be eliminated or end up in materials that are sent abroad to undergo further recovery processes. Only a reduced amount of ENMs will flow back to the productive process of the economy in a limited number of sectors. Overall, the results suggest that risk assessment during recycling should focus on occupational exposure, release of ENMs in landfills and incineration plants, and toxicity assessment in a small number of recycled inputs.

  5. Leaching Behavior of Al, Co and W from the Al-Alloying Treated WC-Co Tool as a New Recycling Process for WC Hard Scrap

    Directory of Open Access Journals (Sweden)

    Jaeryeong Lee

    2016-07-01

    Full Text Available The Al-alloying treated tungsten carbide (WC-Co tool was subjected to grinding using a jaw crusher and planetary mill followed by three wet chemical treatment steps to establish an effective recycling process for WC scraps, especially those generated as bulky and hard scrap. This alloyed WC tool was readily ground to a powder of 1 mm or less and divided into two portions that were 150 µm in size. The wet chemical treatments enabled us to recover W to 69.44% from the under-sized 150 µm and also obtain WC powders from the over-sized 150 µm with a high purity of 98.9% or more.

  6. Fate of antibiotics during municipal water recycling treatment processes.

    Science.gov (United States)

    Le-Minh, N; Khan, S J; Drewes, J E; Stuetz, R M

    2010-08-01

    Municipal water recycling processes are potential human and environmental exposure routes for low concentrations of persistent antibiotics. While the implications of such exposure scenarios are unknown, concerns have been raised regarding the possibility that continuous discharge of antibiotics to the environment may facilitate the development or proliferation of resistant strains of bacteria. As potable and non-potable water recycling schemes are continuously developed, it is imperative to improve our understanding of the fate of antibiotics during conventional and advanced wastewater treatment processes leading to high-quality water reclamation. This review collates existing knowledge with the aim of providing new insight to the influence of a wide range of treatment processes to the ultimate fate of antibiotics during conventional and advanced wastewater treatment. Although conventional biological wastewater treatment processes are effective for the removal of some antibiotics, many have been reported to occur at 10-1000 ng L(-1) concentrations in secondary treated effluents. These include beta-lactams, sulfonamides, trimethoprim, macrolides, fluoroquinolones, and tetracyclines. Tertiary and advanced treatment processes may be required to fully manage environmental and human exposure to these contaminants in water recycling schemes. The effectiveness of a range of processes including tertiary media filtration, ozonation, chlorination, UV irradiation, activated carbon adsorption, and NF/RO filtration has been reviewed and, where possible, semi-quantitative estimations of antibiotics removals have been provided.

  7. Rubber Recycling: Chemistry, Processing, and Applications

    NARCIS (Netherlands)

    Myhre, M.; Saiwari, S.; Dierkes, W.K.; Noordermeer, J.W.M.

    2012-01-01

    For both environmental and economic reasons, there is broad interest in recycling rubber and in the continued development of recycling technologies. The use of postindustrial materials is a fairly well-established and documented business. Much effort over the past decade has been put into dealing wi

  8. Scaling up of manufacturing processes of recycled carpet based composites

    Science.gov (United States)

    Lakshminarayanan, Krishnan

    2011-12-01

    In this work, feasibility of recycling post-consumer carpets using a modified vacuum assisted resisted molding process into large-scale components was successfully demonstrated. The scale up also included the incorporation of nano-clay films in the carpet composites. It is expected that the films will enhance the ability of the composite to withstand environmental degradation and also serve as a fire retardant. Low-cost resins were used to fabricate the recycled carpet-based composites. The scale up in terms of process was achieved by manufacturing composites without a hot press and thereby saving additional equipment cost. Mechanical and physical properties were evaluated. Large-scale samples demonstrated mechanical properties that were different from results from small samples. Acoustic tests indicate good sound absorption of the carpet composite. Cost analysis of the composite material based on the cost of the raw materials and the manufacturing process has been presented.

  9. Sustainable commercial nanocrystalline cellulose manufacturing process with acid recycling.

    Science.gov (United States)

    Sarma, Saurabh Jyoti; Ayadi, Mariem; Brar, Satinder Kaur; Berry, Richard

    2017-01-20

    Nanocrystalline cellulose (NCC) is a biomaterial having potential applications in a wide range of industries. It is industrially produced by concentrated acid hydrolysis of cellulosic materials. In this process, the sulfuric acid rich liquor can be concentrated and reused. However, removal of sugar monomers and oligomers is necessary for such recycling. Membrane and ion exchange technology can be employed to remove sugars; however, such technologies are not efficient in meeting the quality required to recycle the acid solution. As a part of the present study, activated carbon (AC) has been evaluated as an adsorbent for sugar removal from the acidic solution generated during commercial nanocrystalline cellulose manufacturing process. Almost complete removal of sugar can be achieved by this approach. The maximum sugar removal observed during this study was 3.4g/g of AC. Based on this finding, a sustainable method has been proposed for commercial nanocrystalline cellulose manufacturing.

  10. Recycling and surface erosion processes in contemporary tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    McCracken, G.M.

    1979-03-01

    A number of global models have recently had considerable success in describing recycling. These are briefly reviewed. It is shown that large gas concentrations can build up in the walls and that these concentrations are seriously affected by erosion and deposition processes and by deliberate gettering with titanium. Finally, the measurement of the concentration of hydrogen in probes is discussed as a means of measuring plasma edge characteristics.

  11. Scientific Opinion on the safety assessment of the process “Petra Polimeri” used to recycle polypropylene trays and insert trays for use as food contact material

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2014-07-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the recycling process “Petra Polimeri”, EC register number RECYC089. The process recycles polypropylene (PP trays and inserts trays which have been used for the transport, storage and display of whole, fresh fruits and vegetables at room temperature or below. Trays are returned by consumers and collected in specific containers at the point of sale and insert trays originate from a closed loop of distributors. After collection, trays and insert trays are sorted separately. Through this process, sorted trays and/or insert trays are ground into flakes, which are washed, dried and extruded into granules. This recycled material is used up to 30 % with virgin PP to manufacture new trays and insert trays intended for transport, storage and display of whole, fresh fruits and vegetables. The Panel considered the specific use of the recycled trays and insert trays and the management of the input material as a critical process step. The Panel concluded that exposure of consumers to potential contaminants is unlikely and that the recycled PP obtained from the process Petra Polimeri is not of safety concern when i made with collected trays from specific containers at the point of sale along with a communication and/or insert trays from the retailer, trays and insert trays being collected and sorted separately; the sorting being positive and manual, and leading to more than 99.9 % PP trays and insert trays, and when ii intended to be used up to 30 % with virgin PP to manufacture new recycled trays and/or insert trays for contact with whole, fresh fruits and vegetables at room temperature or below.

  12. Recycling of the Granite Quarries and Municipal Incinerator Wastes for the Processing of New Materials as Porcelainized Stoneware

    Directory of Open Access Journals (Sweden)

    Hernández-Crespo, M. S.

    2000-12-01

    Full Text Available In the 1980s started in the ceramic sector the material conception of porcelainized stoneware, a product with versatile and modern characteristics similar to those of the natural stone, depicting improved properties to the marble and granite. Porcelanized stoneware is a compact ceramic material, very hard and homogeneous, generally not fully vitreous (unglazed in its surface, obtained by fast firing from compositions enriched in kaolinite, which contain a large quantity of fluxes. The raw materials for body are a mixture that contains an adequate relationship of kaolinitic clays, feldspars and quartz. Such material is characterized by its low or almost zero porosity, being adequated to sustain heavy and high traffic intensity for uses in and outside of buildings with wide range of aspects, desings and colors. By considering the chemistry and mineralogical composition of the granite and incinerator wastes, this paper describes their use in the processing of construction materials, specifically, in a new type of stoneware flooring and covering materials. According to the most of the physical and mechanical properties here determined, these "Modified Porcelainized Stoneware" (MPS materials are close to the conventional porcelainized stoneware and glass ceramics products.

    Hacia la década de los años 80 se inicia en el sector cerámico la concepción del gres porcelánico, material de características modernas y versátiles semejantes a las de la piedra natural, pero que incluso supera en utilidad y prestaciones al mármol y al granito. El gres porcelánico es un material cerámico compacto, muy duro y homogéneo, no vidriado en su superficie, obtenido por cocción rápida de composiciones ricas en caolinita y una gran cantidad de fundentes; es decir, de una mezcla cerámica que contiene una relación adecuada de arcillas de tipo caolinítico, feldespatos y cuarzo. Dicho material se caracteriza por su baja o casi nula porosidad; es ideal

  13. A closed loop process for recycling spent lithium ion batteries

    Science.gov (United States)

    Gratz, Eric; Sa, Qina; Apelian, Diran; Wang, Yan

    2014-09-01

    As lithium ion (Li-ion) batteries continue to increase their market share, recycling Li-ion batteries will become mandatory due to limited resources. We have previously demonstrated a new low temperature methodology to separate and synthesize cathode materials from mixed cathode materials. In this study we take used Li-ion batteries from a recycling source and recover active cathode materials, copper, steel, etc. To accomplish this the batteries are shredded and processed to separate the steel, copper and cathode materials; the cathode materials are then leached into solution; the concentrations of nickel, manganese and cobalt ions are adjusted so NixMnyCoz(OH)2 is precipitated. The precipitated product can then be reacted with lithium carbonate to form LiNixMnyCozO2. The results show that the developed recycling process is practical with high recovery efficiencies (∼90%), and 1 ton of Li-ion batteries has the potential to generate 5013 profit margin based on materials balance.

  14. Optimization of biodiesel production process using recycled vegetable oil

    Science.gov (United States)

    Lugo, Yarely

    Petro diesel toxic emissions and its limited resources have created an interest for the development of new energy resources, such as biodiesel. Biodiesel is traditionally produced by a transesterification reaction between vegetable oil and an alcohol in the presence of a catalyst. However, this process is slow and expensive due to the high cost of raw materials. Low costs feedstock oils such as recycled and animal fats are available but they cannot be transesterified with alkaline catalysts due to high content of free fatty acids, which can lead to undesirable reactions such as saponification. In this study, we reduce free fatty acids content by using an acid pre-treatment. We compare sulfuric acid, hydrochloric acid and ptoluenesulfonic acid (PTSA) to pre-treat recycled vegetable oil. PTSA removes water after 60 minutes of treatment at room temperature or within 15 minutes at 50°C. The pretreatment was followed by a transesterification reaction using alkaline catalyst. To minimize costs and accelerate reaction, the pretreatment and transesterification reaction of recycle vegetable oil was conducted at atmospheric pressure in a microwave oven. Biodiesel was characterized using a GC-MS method.

  15. Economic considerations of battery recycling based on the Recytec process

    Science.gov (United States)

    Ammann, Pierre

    The Recytec process is successfully operated on a continuous industrial base since autumn 1994. All the products are regularly re-used without any problems and environmental limits are fully respected. The European Community Battery Directive is valid since many years and only a few countries like Switzerland and The Netherlands have implemented it in national guidelines. In the meantime, battery producers have accepted the necessity of the recycling of mercury-free batteries in order to prevent the contamination of municipal waste streams by other heavy metals, such as zinc and cadmium. Recycling processes like the Recytec process are considered by the battery producers as highly expensive and they are looking for cheaper alternatives. Steel works are confronted with a market change and have to produce less quantities of better quality steels with more stringent environmental limits. The electric arc furnace (EAF), one of the chosen battery destruction techniques, is producing 20% of the European steel. Even if the battery mixes contain only mercury-free batteries, the residual mercury content and the zinc concentration will be too high to insure a good steel quality, if all collected batteries will be fed in EAF. In Waelz kilns (production of zinc oxide concentrates for zinc producers) the situation is the same with regard to the residual mercury concentration and environmental limits. Sorting technologies for the separation of battery mixes into the different battery chemistries will presently fail because the re-users of these sorted mercury-free batteries are not able to accept raw waste batteries but they are interested in some fractions of them. This means that in any case pretreatment is an unavoidable step before selective reclamation of waste batteries. The Recytec process is the low-cost partner in a global strategy for battery recycling. This process is very flexible and will be able to follow, with slight and inexpensive adaptations of the equipment

  16. Processing and Validation of Whey-Protein-Coated Films and Laminates at Semi-Industrial Scale as Novel Recyclable Food Packaging Materials with Excellent Barrier Properties

    Directory of Open Access Journals (Sweden)

    E. Bugnicourt

    2013-01-01

    Full Text Available A biopolymer coating for plastic films was formulated based on whey protein, and its potential to replace current synthetic oxygen barrier layers used in food packaging such as ethylene vinyl alcohol copolymers (EVOH was tested. The whey-coating application was performed at semi-industrial scale. High barrier to oxygen with transmission rate down to ranges of 1 cm3 (STP m−2 d−1 bar−1 at and 50% relative humidity (r.h. but interesting humidity barrier down to ranges of 3 g m−2 d−1 (both normalized to 100 μm thickness were reached, outperforming most existing biopolymers. Coated films were validated for storing various food products showing that the shelf life and sensory attributes were maintained similar to reference packaging films while complying with food safety regulations. The developed whey coating could be enzymatically removed within 2 hours and is therefore compatible with plastic recycling operations to allow multilayer films to become recyclable by separating the other combined layers. A life cycle assessment was performed showing a significant reduction in the environmental impact of the packaging thanks in particular to the possibility of recycling materials as opposed to incinerating those containing EVOH or polyamide (PA, but due to the use of biosourced raw materials.

  17. The role of recycle oil in direct coal liquefaction process development

    Energy Technology Data Exchange (ETDEWEB)

    Burke, F.P.

    1995-08-01

    It has long been recognized that use of a recycle oil is a convenient and perhaps necessary feature of a practical direct coal liquefaction process. The recycle oil performs a number of important functions. It serves as a vehicle to convey coal into the liquefaction reactor and products from the reactor. It is a medium for mass and heat transfer among the solid, liquid, and gaseous components of the reactor inventory. It can act as a reactant or intermediate in the liquefaction process. Therefore, the nature of the recycle oil can have a determining effect on process configuration and performance, and the characterization of recycle oil composition and chemistry has been the subject of considerable interest. This paper discusses recycle oil characterization and its influence on the industrial development of coal liquefaction technology,

  18. Serbia: A new process for waste rubber and plastic recycling

    Directory of Open Access Journals (Sweden)

    Ozren Ocic

    2010-02-01

    Full Text Available This paper intends to describe a new technological process for waste rubber and plastic recycling up to the commercial components in safe environmental friendly way. Researches and all relevant technical-technological data related to this process are checked at constructed pilot plant. The future construction of these units for waste rubber and plastic recycling will allow interested parties to achieve the environmental effectiveness and economic efficiency.

  19. Revealing Invisible Water: Moisture Recycling as an Ecosystem Service.

    Science.gov (United States)

    Keys, Patrick W; Wang-Erlandsson, Lan; Gordon, Line J

    2016-01-01

    An ecosystem service is a benefit derived by humanity that can be traced back to an ecological process. Although ecosystem services related to surface water have been thoroughly described, the relationship between atmospheric water and ecosystem services has been mostly neglected, and perhaps misunderstood. Recent advances in land-atmosphere modeling have revealed the importance of terrestrial ecosystems for moisture recycling. In this paper, we analyze the extent to which vegetation sustains the supply of atmospheric moisture and precipitation for downwind beneficiaries, globally. We simulate land-surface evaporation with a global hydrology model and track changes to moisture recycling using an atmospheric moisture budget model, and we define vegetation-regulated moisture recycling as the difference in moisture recycling between current vegetation and a hypothetical desert world. Our results show that nearly a fifth of annual average precipitation falling on land is from vegetation-regulated moisture recycling, but the global variability is large, with many places receiving nearly half their precipitation from this ecosystem service. The largest potential impacts for changes to this ecosystem service are land-use changes across temperate regions in North America and Russia. Likewise, in semi-arid regions reliant on rainfed agricultural production, land-use change that even modestly reduces evaporation and subsequent precipitation, could significantly affect human well-being. We also present a regional case study in the Mato Grosso region of Brazil, where we identify the specific moisture recycling ecosystem services associated with the vegetation in Mato Grosso. We find that Mato Grosso vegetation regulates some internal precipitation, with a diffuse region of benefit downwind, primarily to the south and east, including the La Plata River basin and the megacities of Sao Paulo and Rio de Janeiro. We synthesize our global and regional results into a generalized

  20. Revealing Invisible Water: Moisture Recycling as an Ecosystem Service.

    Directory of Open Access Journals (Sweden)

    Patrick W Keys

    Full Text Available An ecosystem service is a benefit derived by humanity that can be traced back to an ecological process. Although ecosystem services related to surface water have been thoroughly described, the relationship between atmospheric water and ecosystem services has been mostly neglected, and perhaps misunderstood. Recent advances in land-atmosphere modeling have revealed the importance of terrestrial ecosystems for moisture recycling. In this paper, we analyze the extent to which vegetation sustains the supply of atmospheric moisture and precipitation for downwind beneficiaries, globally. We simulate land-surface evaporation with a global hydrology model and track changes to moisture recycling using an atmospheric moisture budget model, and we define vegetation-regulated moisture recycling as the difference in moisture recycling between current vegetation and a hypothetical desert world. Our results show that nearly a fifth of annual average precipitation falling on land is from vegetation-regulated moisture recycling, but the global variability is large, with many places receiving nearly half their precipitation from this ecosystem service. The largest potential impacts for changes to this ecosystem service are land-use changes across temperate regions in North America and Russia. Likewise, in semi-arid regions reliant on rainfed agricultural production, land-use change that even modestly reduces evaporation and subsequent precipitation, could significantly affect human well-being. We also present a regional case study in the Mato Grosso region of Brazil, where we identify the specific moisture recycling ecosystem services associated with the vegetation in Mato Grosso. We find that Mato Grosso vegetation regulates some internal precipitation, with a diffuse region of benefit downwind, primarily to the south and east, including the La Plata River basin and the megacities of Sao Paulo and Rio de Janeiro. We synthesize our global and regional results

  1. FY 1999 development of a technology to recycle fabric products. Development of a technology to recover 'waste selvages' generated from weaving process and recycle them as fabric products; 1999 nendo sen'i seihin recycle gijutsu kaihatsu seika hokokusho. Seishoku no sai ni hasseisuru 'sutemimi' wo sairiyo shita orimono seihin gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    The development was made of technology to recover 'waste selvages' generated from the weaving process and recycle them as weaving yarn for bath/toiletry products such as bath mats and toilet mats. The FY 1999 results were summarized. Based on the results of the study made in the previous year, research was conducted using a rapier loom made by Saurer Co. to study the effect of change in selvage fabric on the tangling condition of waste yarn. As a result, it was confirmed that 'waste selvage standard' and 'tangling yarn threading chart' were the most suitable. As to the development of technique for winding 'waste selvages,' safety, operability and efficiency were confirmed of the exclusive winding device which moves associated with the waste selvage roller on the yarn supply side. As to the development of technique for sizing, twisting and heat-processing of 'waste selvages,' favorable results were obtained in the test on the sizing of 'waste selvage' in the dyeing process and the heating processing technique using fused yarn. Good results were also obtained in the test using an exclusive double twister on the twisting condition, strength and uniformity of 'waste selvages.' Also in the development of the winding machine corresponding to coarse yarn and the weaving technique corresponding to coarse yarn, the results obtained were favorable. (NEDO)

  2. Ribosome recycling: An essential process of protein synthesis.

    Science.gov (United States)

    Kiel, Michael C; Kaji, Hideko; Kaji, Akira

    2007-01-01

    A preponderance of textbooks outlines cellular protein synthesis (translation) in three basic steps: initiation, elongation, and termination. However, researchers in the field of translation accept that a vital fourth step exists; this fourth step is called ribosome recycling. Ribosome recycling occurs after the nascent polypeptide has been released during the termination step. Despite the release of the polypeptide, ribosomes remain bound to the mRNA and tRNA. It is only during the fourth step of translation that ribosomes are ultimately released from the mRNA, split into subunits, and are free to bind new mRNA, thus the term "ribosome recycling." This step is essential to the viability of cells. In bacteria, it is catalyzed by two proteins, elongation factor G and ribosome recycling factor, a near perfect structural mimic of tRNA. Eukaryotic organelles such as mitochondria and chloroplasts possess ribosome recycling factor and elongation factor G homologues, but the nature of ribosome recycling in eukaryotic cytoplasm is still under investigation. In this review, the discovery of ribosome recycling and the basic mechanisms involved are discussed so that textbook writers and teachers can include this vital step, which is just as important as the three conventional steps, in sections dealing with protein synthesis.

  3. PRETREATMENT AND FRACTIONATION OF CORN STOVER BY AMMONIA RECYCLE PERCOLATION PROCESS. (R831645)

    Science.gov (United States)

    Corn stover was pretreated with aqueous ammonia in a flow-through column reactor,a process termed as Ammonia Recycle Percolation (ARP). The aqueous ammonia causesswelling and efficient delignification of biomass at high temperatures. The ARPprocess solubilizes abou...

  4. Recycling of cellulases in a continuous process for production of bioethanol

    DEFF Research Database (Denmark)

    Haven, Mai Østergaard

    The focus of the work presented in this thesis is recycling of commercial enzymes in a continuous process for production of bioethanol from biomass. To get a deeper understanding of the factors affecting the potential for enzyme recycling, the interactions between enzymes and biomass......, the adsorption and desorption as well as stability and recovery of activity was investigated. More knowledge on these factors have enabled a process adapted for enzyme recycling. The driver being that enzyme consumption remains a major cost when producing bioethanol from lignocellulosic biomass. Unlike previous...

  5. Current and Prospective Li-Ion Battery Recycling and Recovery Processes

    Science.gov (United States)

    Heelan, Joseph; Gratz, Eric; Zheng, Zhangfeng; Wang, Qiang; Chen, Mengyuan; Apelian, Diran; Wang, Yan

    2016-10-01

    The lithium ion (Li-ion) battery industry has been growing exponentially since its initial inception in the late 20th century. As battery materials evolve, the applications for Li-ion batteries have become even more diverse. To date, the main source of Li-ion battery use varies from consumer portable electronics to electric/hybrid electric vehicles. However, even with the continued rise of Li-ion battery development and commercialization, the recycling industry is lagging; approximately 95% of Li-ion batteries are landfilled instead of recycled upon reaching end of life. Industrialized recycling processes are limited and only capable of recovering secondary raw materials, not suitable for direct reuse in new batteries. Most technologies are also reliant on high concentrations of cobalt to be profitable, and intense battery sortation is necessary prior to processing. For this reason, it is critical that a new recycling process be commercialized that is capable of recovering more valuable materials at a higher efficiency. A new technology has been developed by the researchers at Worcester Polytechnic Institute which is capable of recovering LiNi x Mn y Co z O2 cathode material from a hydrometallurgical process, making the recycling system as a whole more economically viable. By implementing a flexible recycling system that is closed-loop, recycling of Li-ion batteries will become more prevalent saving millions of pounds of batteries from entering the waste stream each year.

  6. Process for the production of ultrahigh purity silane with recycle from separation columns

    Science.gov (United States)

    Coleman, Larry M. (Inventor)

    1982-01-01

    Tri- and dichlorosilanes formed by hydrogenation in the course of the reaction of metallurgical silicon, hydrogen and recycle silicon tetrachloride are employed as feed into a separation column arrangement of sequential separation columns and redistribution reactors which processes the feed into ultrahigh purity silane and recycle silicon tetrachloride. A slip stream is removed from the bottom of two sequential columns and added to the recycle silicon tetrachloride process stream causing impurities in the slip streams to be subjected to reactions in the hydrogenation step whereby waste materials can be formed and readily separated.

  7. Modelling production processes in a vehicle recycling plant.

    Science.gov (United States)

    Simic, Vladimir; Dimitrijevic, Branka

    2012-09-01

    The European Directive on end-of-life vehicles (ELVs) fundamentally changed the business philosophy of the European vehicle recycling system, which was exclusively profit-oriented. As the dominant participants of this system, vehicle recycling plants (VRPs) are especially affected by its implementation. For VRPs to successfully respond to the prescribed eco-efficiency quotas, investment will be needed to procure modern sorting equipment as well as to achieve full transformation of their production process. However, before VRPs decide to make this very important investment decision, it is necessary to determine the adequacy of such a decision in detail. Consequently, the following questions become unavoidable: Can modernly equipped VRPs conduct profitable business? Are eco-efficiency quotas actually attainable? How will the new changes in vehicle design influence VRPs? To provide answers to these essential questions, a production planning model of a modernly equipped VRP was first developed and then tested extensively using real data. Based on the answers provided by the proposed model testing analysis it was concluded that VRP transformation is not only necessary but completely justified and that the final success of the ELV Directive is realistic.

  8. Car plastic fuel tanks: closed loop recycling process, design and lifecycle assessment (RECAFUTA)

    Energy Technology Data Exchange (ETDEWEB)

    Yernaux, J-M. [SOLVAY SA, Research and Technology, Brussels (Belgium)

    2001-07-01

    A cooperative European Union-sponsored project to recycle high density plastic material from used automobile fuel tanks back into the original application is discussed. The goal of the project was to introduce 40 per cent of regenerate into new plastic fuel tanks. The project involved the development of design-for-recycling guidelines, development of a process for efficient recovery of the material by using super-critical carbon dioxide directly in the extruder, development of a process for upgrading the recycled material, and life cycle assessment to determine the reliability of the recycling process by comparing it to other alternatives such as landfilling or energy recovery. The project was recently completed and international validation tests are currently underway. The feasibility of upgrading the laboratory extrusion facility to industrial scale is in the process of being evaluated, concurrently with the development of an appropriate business plan. 7 figs.

  9. A Membrane Process for Recycling Die Lube from Wastewater Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Eric S. Peterson; Jessica Trudeau; Bill Cleary; Michael Hackett; William A. Greene

    2003-04-01

    An active-surface membrane technology was used to separate a die lube manufacturing wastewater stream consisting of various oils, hydrocarbons, heavy metals, and silicones. The ultrafiltration membranes reduced organics from initial oil and grease contents by 20–25X, carbon oxygen demand (COD) by 1.5 to 2X, and total organic carbon (TOC) by 0.6, while the biological oxygen demand (BOD) remained constant. The active-surface membranes were not fouled as badly as non-active-surface systems and the active-surface membrane flux levels were consistently higher and more stable than those of the non-active-surface membranes tested. Field testing demonstrated that the rotary microfilter can concentrate the die lube, i.e. remove the glycerin component, and produce a die lube suitable for recycling. The recycling system operated for six weeks with only seven cleaning cycles and no mechanical or electrical failures. Test data and quality records indicate that the die casting scrap was reduced from 8.4 to 7.8%. There is no doubt that this test yielded tremendous results. This separation process presents significant opportunities that can be evaluated further.

  10. A Membrane Process for Recycling Die Lube from Wastewater Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, E. S. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Trudeau, J. [Metaldyne, Inc., Twinsburg, OH (United States); Cleary, B. [Metaldyne, Inc., Twinsburg, OH (United States); Hackett, M. [Metaldyne, Inc., Twinsburg, OH (United States); Greene, W. A. [SpinTek FIltrations, LLC, Los Alamitos, CA (United States)

    2003-04-30

    An active-surface membrane technology was used to separate a die lube manufacturing wastewater stream consisting of various oils, hydrocarbons, heavy metals, and silicones. The ultrafiltration membranes reduced organics from initial oil and grease contents by 20-25X, carbon oxygen demand (COD) by 1.5 to 2X, and total organic carbon (TOC) by 0.6, while the biological oxygen demand (BOD) remained constant. The active-surface membranes were not fouled as badly as non-active-surface systems and the active-surface membrane flux levels were consistently higher and more stable than those of the non-active-surface membranes tested. Field testing demonstrated that the rotary microfilter can concentrate the die lube, i.e. remove the glycerin component, and produce a die lube suitable for recycling. The recycling system operated for six weeks with only seven cleaning cycles and no mechanical or electrical failures. Test data and quality records indicate that the die casting scrap was reduced from 8.4 to 7.8%. There is no doubt that this test yielded tremendous results. This separation process presents significant opportunities that can be evaluated further.

  11. Microbial carbon recycling: an underestimated process controlling soil carbon dynamics

    Science.gov (United States)

    Basler, A.; Dippold, M.; Helfrich, M.; Dyckmans, J.

    2015-07-01

    The mean residence times (MRT) of different compound classes of soil organic matter (SOM) do not match their inherent recalcitrance to decomposition. One reason for this is the stabilisation within the soil matrix, but recycling, i.e. the reuse of "old" organic material to form new biomass may also play a role as it uncouples the residence times of organic matter from the lifetime of discrete molecules in soil. We analysed soil sugar dynamics in a natural 30 years old labelling experiment after a~wheat-maize vegetation change to determine the extent of recycling and stabilisation in plant and microbial derived sugars: while plant derived sugars are only affected by stabilisation processes, microbial sugars may be subject to both, stabilisation and recycling. To disentangle the dynamics of soil sugars, we separated different density fractions (free particulate organic matter (fPOM), light occluded particulate organic matter (≤1.6 g cm-3; oPOM1.6), dense occluded particulate organic matter (≤2 g cm-3; oPOM2) and mineral-associated organic matter (>2 g cm-3; Mineral)) of a~silty loam under long term wheat and maize cultivation. The isotopic signature of sugars was measured by high pressure liquid chromatography coupled to isotope ratio mass spectrometry (HPLC/IRMS), after hydrolysis with 4 M Trifluoroacetic acid (TFA). While apparent mean residence times (MRT) of sugars were comparable to total organic carbon in the bulk soil and mineral fraction, the apparent MRT of sugars in the oPOM fractions were considerably lower than those of the total carbon of these fractions. This indicates that oPOM formation was fuelled by microbial activity feeding on new plant input. In the bulk soil, mean residence times of the mainly plant derived xylose (xyl) were significantly lower than those of mainly microbial derived sugars like galactose (gal), rhamnose (rha), fucose (fuc), indicating that recycling of organic matter is an important factor regulating organic matter dynamics

  12. Recycled poly(ethylene terephthalate) for direct food contact applications: challenge test of an inline recycling process.

    Science.gov (United States)

    Franz, R; Welle, F

    2002-05-01

    Of all the plastics used for packaging, due to its low diffusivity and chemical inertness, poly(ethylene terephthalate) (PET) is one of the favoured candidate plastics for closed-loop recycling for new packaging applications. In the work reported here, a PET-recycling process was investigated with respect to its cleaning efficiency and compliance of the PET recyclate with food law. The key technology of the investigated PET-recycling process to remove contaminants consists of a predecontamination-extruder combination. At the end of the recycling process, there is either a pelletizing system or downstream equipment to produce preforms or flat sheets. Therefore, the process has two process options, an inline production of PET preforms and a batch option producing PET pellets. In the case of possible misuse of PET bottles by the consumer, the inline process produces higher concentrations in the bottle wall of the recyclate containing preforms. Owing to the dilution of the PET output material by large amounts of uncontaminated PET, the batch option is the less critical process in terms of consumer protection. Regarding an appropriate testing procedure for the evaluation of a bottle-to-bottle recycling process, both process options have their own specific requirements with respect to the design of a challenge test. A novel challenge test approach to the inline mode of a recycling process is presented here.

  13. Lead-acid battery recycling and the new Isasmelt process

    Energy Technology Data Exchange (ETDEWEB)

    Ramus, K. (Britannia Refined Metals Ltd., Northfleet (United Kingdom)); Hawkins, P. (Britannia Refined Metals Ltd., Northfleet (United Kingdom))

    1993-01-29

    The recovery of lead/acid batteries has long been practised for economic reasons. More recently, battery recovery has also been influenced by environmental concerns, both in the general community and within the recycling plants. These influences will probably increase in the future. With these factors in mind, Britannia Refined Metals Ltd. introduced new technology for battery recycling at its Northfleet, UK operations in 1991. A process description of the Britannia Refined Metals Secondary Lead Operation, the reasons for selecting an Engitec CX battery breaking plant in combination with an Isasmelt Paste Smelting Furnace, and commissioning and current operation of the plant are discussed. (orig.)

  14. Development of a recycling process for tantalum from capacitor scraps

    Science.gov (United States)

    Mineta, Kunio; Okabe, Toru H.

    2005-02-01

    A process based on oxidation treatment at elevated temperature, followed by mechanical separation and chemical treatment, was investigated to develop an effective process for recycling tantalum from capacitor scraps. By this process, tantalum oxide powder, free of SiO2 or other impurities, was recovered from capacitor scrap. Tantalum powder with 99 mass% purity was recovered by magnesiothermic reduction of the obtained tantalum oxide powder.

  15. Designing and examining e-waste recycling process: methodology and case studies.

    Science.gov (United States)

    Li, Jinhui; He, Xin; Zeng, Xianlai

    2017-03-01

    Increasing concerns on resource depletion and environmental pollution have largely obliged electrical and electronic waste (e-waste) should be tackled in an environmentally sound manner. Recycling process development is regarded as the most effective and fundamental to solve the e-waste problem. Based on global achievements related to e-waste recycling in the past 15 years, we first propose a theory to design an e-waste recycling process, including measuring e-waste recyclability and selection of recycling process. And we summarize the indicators and tools in terms of resource dimension, environmental dimension, and economic dimension, to examine the e-waste recycling process. Using the sophisticated experience and adequate information of e-waste management, spent lithium-ion batteries and waste printed circuit boards are chosen as case studies to implement and verify the proposed method. All the potential theory and obtained results in this work can contribute to future e-waste management toward best available techniques and best environmental practices.

  16. Theoretical Foundation of Carbonation Pellet Process for Ferrous Sludge Recycling

    Institute of Scientific and Technical Information of China (English)

    HU Chang-qing; HAN Tao; ZHANG Yu-zhu; ZHANG Zhi-xia

    2011-01-01

    For the recycling of ferrous sludge from steel industry,the carbonation pellet process should be considered as a "green" process,since no impurities are added as well as CO2 can be sequestrated and consumed.Through the thermodynamic calculation,the carbonation reaction can occur spontaneously and is an exothermic reaction.Based on the kinetic analysis through unreacted core model,the interfacial chemical reaction was the rate controlling step in the initial fast stage of carbonation,and the CO2 diffusion through the CaCO3 product layer was the rate controlling step in the following extremely slow stage.For the carbonation bonded mechanism,the pellet strength was gained by the formation and growing of CaCO3 product layer.Since the interfacial chemical reaction was the critical stage of the entire carbonation process,the emphasizes should be focused on the improvement of sorbent activity and the optimization of process parameters,such as pore structure,pore surface area,and total pressure,CO2 partial pressure,reaction temperature,etc to accelerate the reaction rate and to improve the quality of carbonation pellets.

  17. Optimisation of the steel plant dust recycling process

    Science.gov (United States)

    Popescu, Darius-Alexandru; Hepuť, Teodor; Puťan, Vasile

    2016-06-01

    The widespread use of oxygen in the EAF steel-making process led to the increase of furnace productivity and reduction of specific energy consumption. Following the increase of the metal bath temperature, the brown smoke exhaust process is intensified, which requires mandatory gas treatment. The steel plant dust resulting from the treatment of waste gases is a manufacturing waste which must be recycled in the steel plant. Due to the fineness of the waste, when conducting the researches we processed it through pelletization. The processing of this waste aims not only its granulometric composition, but also the chemical composition (mainly the zinc content). After processing the data, we choose the optimal waste recycling technology based on the resistance of pellets and final content of zinc.

  18. Polybrominated diphenyl ethers in indoor air during waste TV recycling process

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Jie [School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Lin, Kuangfei; Deng, Jingjing; Fu, Xiaoxu [State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai 200237 (China); Xu, Zhenming, E-mail: zmxu@sjtu.edu.cn [School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China)

    2015-02-11

    Graphical abstract: - Highlights: • Air in the workshops was seriously contaminated by TV recycling activities. • PBDEs profiles and levels varied with particulate matters and different workshops. • Equilibrium between gas-particle partitioning was disrupted by recycling process. • The highest occupational exposure concentrations occurred during heating process. - Abstract: Recycling process for waste TV sets mainly consists of dismantling, printed wiring board (PWB) heating, PWB recycling, and plastic crushing in formal recycling plant. Polybrominated diphenyl ethers (PBDEs) contained in waste TV sets are released to indoor air. Air samples at 4 different workshops were collected to measure the PBDEs concentrations in both gaseous and particulate phases. The mean concentrations of ∑PBDEs in indoor air were in the range of 6780–2,280,000 pg/m{sup 3}. The highest concentration in gaseous phase (291,000 pg/m{sup 3}) was detected in the PWB heating workshop. The ∑{sub 12}PBDEs concentrations in PM{sub 2.5} and PM{sub 10} at the 4 workshops ranged in 6.8–6670 μg/g and 32.6–6790 μg/g, respectively. The gas-particle partitioning of PBDEs was disrupted as PBDEs were continuously released during the recycling processes. Occupational exposure assessment showed that only the exposure concentration of BDE-47 (0.118 μg/kg/day) through inhalation in the PWB heating workshop for workers without facemask exceeded the reference dose (0.1 μg/kg/day), posing a health hazard to workers. All the results demonstrated that recycling of TV sets was an important source of PBDEs emission, and PBDEs emission pollution was related to the composition of TV sets, interior dust, and recycling process.

  19. Recycling of mill scale in sintering process

    Directory of Open Access Journals (Sweden)

    El-Hussiny N.A.

    2011-01-01

    Full Text Available This investigation deals with the effect of replacing some amount of Baharia high barite iron ore concentrate by mill scale waste which was characterized by high iron oxide content on the parameters of the sintering process., and investigation the effect of different amount of coke breeze added on sintering process parameters when using 5% mill scale waste with 95% iron ore concentrate. The results of this work show that, replacement of iron ore concentrate with mill scale increases the amount of ready made sinter, sinter strength and productivity of the sinter machine and productivity at blast furnace yard. Also, the increase of coke breeze leads to an increase the ready made sinter and productivity of the sintering machine at blast furnace yard. The productivity of the sintering machine after 5% decreased slightly due to the decrease of vertical velocity.

  20. Polybrominated diphenyl ethers in indoor air during waste TV recycling process.

    Science.gov (United States)

    Guo, Jie; Lin, Kuangfei; Deng, Jingjing; Fu, Xiaoxu; Xu, Zhenming

    2015-01-01

    Recycling process for waste TV sets mainly consists of dismantling, printed wiring board (PWB) heating, PWB recycling, and plastic crushing in formal recycling plant. Polybrominated diphenyl ethers (PBDEs) contained in waste TV sets are released to indoor air. Air samples at 4 different workshops were collected to measure the PBDEs concentrations in both gaseous and particulate phases. The mean concentrations of ∑PBDEs in indoor air were in the range of 6780-2,280,000 pg/m(3). The highest concentration in gaseous phase (291,000 pg/m(3)) was detected in the PWB heating workshop. The ∑12PBDEs concentrations in PM2.5 and PM10 at the 4 workshops ranged in 6.8-6670 μg/g and 32.6-6790 μg/g, respectively. The gas-particle partitioning of PBDEs was disrupted as PBDEs were continuously released during the recycling processes. Occupational exposure assessment showed that only the exposure concentration of BDE-47 (0.118 μg/kg/day) through inhalation in the PWB heating workshop for workers without facemask exceeded the reference dose (0.1 μg/kg/day), posing a health hazard to workers. All the results demonstrated that recycling of TV sets was an important source of PBDEs emission, and PBDEs emission pollution was related to the composition of TV sets, interior dust, and recycling process.

  1. Recycling high density tungsten alloy powder by oxidization-reduction process

    Institute of Scientific and Technical Information of China (English)

    张兆森; 陈立宝; 贺跃辉; 黄伯云

    2002-01-01

    The processes of directly recycling high density tungsten alloy by oxidation-reduction technique were investigated. The particle size of recycled powder is fine, and the shape of powder particle is regular when the final reduction temperature is 850℃, in which the average size of the tungsten alloy particles reduced is about 1.5μm. The average size of the alloy particles increase to 6μm and 9μm when increasing the reduction temperature to 900℃ and 950℃, respectively. However, if the reduction temperature is higher than 900℃, the surface feature of powder is complicated. Increasing reduction temperature from 900℃ to 950℃, the content of oxygen of recycled powder decreases from 0.2314% to 0.1700%, and powder particles grow slightly. It has been also found that the chemical composition of the recycled alloy powder is the same as the initial powder.

  2. Water recycle treatment system for use in metal processing

    Energy Technology Data Exchange (ETDEWEB)

    Hewitt, D.E.; Dando, T.J.

    1976-08-10

    A water recycle treatment system is described comprising two main treatment sub-systems for treatment of contaminated water from a plurality of concentrated solutions and rinse baths to separate out the impurities therein. A first sub-system treats less concentrated solutions used for the rinse baths by channeling the flow therefrom to a first neutralizing tank which provides for pH control to produce a mixed output solution having a substantially constant pH factor, which is filtered to remove gross particles, the filtered solution being cooled in a holding tank and passed through a reverse osmosis process and carbon bed to produce clean water. The second sub-system treats highly concentrated solutions obtained from a plurality of chemical processes, mixes them in a second neutralizing tank which is utilized to produce a substantially constant pH output, which is fed to an evaporator to precipitate the metals and salts in sludge and also forms a water vapor output. The reverse osmosis waste is fed back into the second neutralizing tank and processed as noted above.

  3. Modeling Regional Recycling and Remanufacturing Processes: From Micro to Macro

    OpenAIRE

    Joyce Cooper; Randall Jackson; Nancey Green Leigh

    2008-01-01

    This paper reports progress in modeling recycling and remanufacturing processes within metropolitan regional economies at the micro and macro levels. The paper presents interim results from a multi-year, inter-institutional research project funded by the National Science Foundation. We identify a number of issues that have arisen from an in-depth industry level analysis of obsolete and waste products generated in the Seattle, WA and Atlanta, GA metro regions from waste electronics (e-waste) a...

  4. Estimated costs of implementation of membrane processes for on-site greywater recycling.

    Science.gov (United States)

    Humeau, P; Hourlier, F; Bulteau, G; Massé, A; Jaouen, P; Gérente, C; Faur, C; Le Cloirec, P

    2011-01-01

    Greywater reuse inside buildings is a possible way to preserve water resources and face up to water scarcity. This study is focused on a technical-economic analysis of greywater treatment by a direct nanofiltration (NF) process or by a submerged membrane bioreactor (SMBR) for on-site recycling. The aim of this paper is to analyse the cost of recycled water for two different configurations (50 and 500 inhabitants) in order to demonstrate the relevance of the implementation of membrane processes for greywater recycling, depending on the production capacity of the equipment and the price of drinking water. The first step was to define a method to access the description of the cost of producing recycled water. The direct costs were defined as a sum of fixed costs due to equipment, maintenance and depreciation, and variable costs generated by chemical products and electricity consumptions. They were estimated from an experimental approach and from data found in literature, enabling operating conditions for greywater recycling to be determined. The cost of treated water by a SMBR unit with a processing capacity of 500 persons is close to 4.40 euros m(-3), while the cost is 4.81 euros m(-3) with a NF process running in the same conditions. These costs are similar to the price of drinking water in some European countries.

  5. Simulation of cutting process in the cable recycling system

    Science.gov (United States)

    Li, Yang; Luo, Zhen; Song, Kailei; Ao, Sansan; Wang, Rui

    2011-05-01

    The utilization of Waste Electrical and Electronic Equipment is a hot spot in environmental protection field presently and the resource utilization of cable wastes is an important subject. An enormous amount of electrical cable is disposed of as scrap each year. In order to recycle the valuable copper wires, cable granulator technique is used widely. However, one of the shortcomings of this technique is it has serious tool wear. In order to better understand the reason for tool wear, this paper simulates the stress and strain distribution in the cutting tool and copper during the cutting process in cable granulator by finite element method. The result shows that a tensile stress region, which is the main reason for blade tipping, appeared in the upper blade. Besides, the tensile stress in the right side of upper blade is higher than that in the left side. Therefore, in order to extend the life of cutter, we suggest using different materials in different stress zone to manufacture cutting tool. After the cutter was worn out, the right side of the blade can be renovated using material with well tensile performance through overlaying welding, as well as the left side of the blade can be renovated by material with high red hardness, high wear resistance, and high compression strength through overlaying welding. This method can reduce the consumption of precious metals and raise the utilization rate of materials.

  6. Recycled Concrete as Aggregate for Structural Concrete Production

    Directory of Open Access Journals (Sweden)

    Mirjana Malešev

    2010-04-01

    Full Text Available A comparative analysis of the experimental results of the properties of fresh and hardened concrete with different replacement ratios of natural with recycled coarse aggregate is presented in the paper. Recycled aggregate was made by crushing the waste concrete of laboratory test cubes and precast concrete columns. Three types of concrete mixtures were tested: concrete made entirely with natural aggregate (NAC as a control concrete and two types of concrete made with natural fine and recycled coarse aggregate (50% and 100% replacement of coarse recycled aggregate. Ninety-nine specimens were made for the testing of the basic properties of hardened concrete. Load testing of reinforced concrete beams made of the investigated concrete types is also presented in the paper. Regardless of the replacement ratio, recycled aggregate concrete (RAC had a satisfactory performance, which did not differ significantly from the performance of control concrete in this experimental research. However, for this to be fulfilled, it is necessary to use quality recycled concrete coarse aggregate and to follow the specific rules for design and production of this new concrete type.

  7. Improvement of Bearing Capacity in Recycled Aggregates Suitable for Use as Unbound Road Sub-Base

    Directory of Open Access Journals (Sweden)

    Laura Garach

    2015-12-01

    Full Text Available Recycled concrete aggregates and mixed recycled aggregates are specified as types of aggregates with lower densities, higher water absorption capacities, and lower mechanical strength than natural aggregates. In this paper, the mechanical behaviour and microstructural properties of natural aggregates, recycled concrete aggregates and mixed recycled aggregates were compared. Different specimens of unbound recycled mixtures demonstrated increased resistance properties. The formation of new cement hydrated particles was observed, and pozzolanic reactions were discovered by electronon microscopy in these novel materials. The properties of recycled concrete aggregates and mixed recycled aggregates suggest that these recycled materials can be used in unbound road layers to improve their mechanical behaviour in the long term.

  8. Recycling of construction debris as aggregate in the Mid-Atlantic Region, USA

    Science.gov (United States)

    Robinson, G.R.; Menzie, W.D.; Hyun, H.

    2004-01-01

    Reclaimed asphalt pavement (RAP) and portland cement concrete (RPCC) are abundant and available substitutes for natural aggregate in many areas. This paper presents an overview of factors that affect recycled aggregate cost, availability, and engineering performance, and the results of a survey of business practices in the Mid-Atlantic region. For RAP, processing costs are less than those for virgin natural aggregate. Use of efficient asphalt pavement stripping technology, on-site reclamation, and linked two-way transport of asphalt debris and processed asphalt paving mix between asphalt mix plants and paving sites has led to extensive recycling of asphalt pavement in the Mid-Atlantic region of the US. Most of the sites that recycle asphalt pavement (RAP) are located in or near urban areas close to important transportation corridors. RPCC is a viable aggregate source in urban settings where unit costs for processed aggregate from RPCC and natural aggregate are comparable. Disposal fees charged at RPCC recycling sites help defray processing costs and the significantly lower tipping fees at recycling sites versus landfill disposal sites encourage recycling of construction debris as aggregate. Construction contractors and construction debris recycling centers, many of which have the ability to crush and process concrete debris at the job site, produce most RPCC. Production of RPCC aggregate from construction debris that is processed on site using portable equipment moved to the construction site eliminates transportation costs for aggregate and provides an economic incentive for RPCC use. Processing costs, quality and performance issues, and lack of large quantities where needed limit RPCC use. Most RPCC suppliers in the Mid-Atlantic area are located in counties with population densities greater than 400 people/km2 (1036 people/mile2) and that have high unit-value costs and limited local availability of natural aggregate. ?? 2004 Published by Elsevier B.V.

  9. Reading as functional coordination: not recycling but a novel synthesis

    Directory of Open Access Journals (Sweden)

    Thomas eLachmann

    2014-09-01

    Full Text Available The Functional Coordination approach describes the processes involved in learning to read as a form of procedural learning in which pre-existing skills, mainly from the visual and auditory domain, are (1 recruited, (2 modified and (3 coordinated to create the procedures for reading text, which form the basis of subsequent (4 automatization. In this context, we discuss evidence relating to the emerging prevalence of analytic processing in letter perception. We argue that the process of learning to read does not have to lead to a loss of perceptual skill as consequence of a cultural recycling; learning to read just leads to a novel synthesis of functions, which are coordinated for reading and then automatized as a package over several years. Developmental dyslexia is explained within this framework as a Functional Coordination Deficit (Lachmann, 2002, since the coordination level is assumed to be most liable to manifest deficiencies. This is because, at this level, the greatest degree of fine tuning of complex functions is required. Thus, developmental dyslexia is not seen as a consequence of a deficient automatization per se, but of automatization of abnormally developed functional coordination.

  10. Reading as functional coordination: not recycling but a novel synthesis.

    Science.gov (United States)

    Lachmann, Thomas; van Leeuwen, Cees

    2014-01-01

    The Functional Coordination approach describes the processes involved in learning to read as a form of procedural learning in which pre-existing skills, mainly from the visual, and auditory domain, are (1) recruited, (2) modified, and (3) coordinated to create the procedures for reading text, which form the basis of subsequent (4) automatization. In this context, we discuss evidence relating to the emerging prevalence of analytic processing in letter perception. We argue that the process of learning to read does not have to lead to a loss of perceptual skill as consequence of a "cultural recycling"; learning to read just leads to a novel synthesis of functions, which are coordinated for reading and then automatized as a package over several years. Developmental dyslexia is explained within this framework as a Functional Coordination Deficit (Lachmann, 2002), since the coordination level is assumed to be most liable to manifest deficiencies. This is because, at this level, the greatest degree of fine tuning of complex functions is required. Thus, developmental dyslexia is not seen as a consequence of a deficient automatization per se, but of automatization of abnormally developed functional coordination.

  11. Applying decision-making tools to national e-waste recycling policy: an example of Analytic Hierarchy Process.

    Science.gov (United States)

    Lin, Chun-Hsu; Wen, Lihchyi; Tsai, Yue-Mi

    2010-05-01

    As policy making is in essence a process of discussion, decision-making tools have in many cases been proposed to resolve the differences of opinion among the different parties. In our project that sought to promote a country's performance in recycling, we used the Analytic Hierarchy Process (AHP) to evaluate the possibilities and determine the priority of the addition of new mandatory recycled waste, also referred to as Due Recycled Wastes, from candidate waste appliances. The evaluation process started with the collection of data based on telephone interviews and field investigations to understand the behavior of consumers as well as their overall opinions regarding the disposal of certain waste appliances. With the data serving as background information, the research team then implemented the Analytic Hierarchy Process using the information that formed an incomplete hierarchy structure in order to determine the priority for recycling. Since the number of objects to be evaluated exceeded the number that the AHP researchers had suggested, we reclassified the objects into four groups and added one more level of pair-wise comparisons, which substantially reduced the inconsistency in the judgment of the AHP participants. The project was found to serve as a flexible and achievable application of AHP to the environmental policy-making process. In addition, based on the project's outcomes derived from the project as a whole, the research team drew conclusions regarding the government's need to take back 15 of the items evaluated, and suggested instruments that could be used or recycling regulations that could be changed in the future. Further analysis on the top three items recommended by the results of the evaluation for recycling, namely, Compact Disks, Cellular Phones and Computer Keyboards, was then conducted to clarify their concrete feasibility. After the trial period for recycling ordered by the Taiwan Environmental Protection Administration, only Computer

  12. Study of Aramid Fiber/Polychloroprene Recycling Process by Thermal Degradation

    Directory of Open Access Journals (Sweden)

    Igor Dabkiewicz

    2016-07-01

    Full Text Available Aramid fiber is an important polymer applied as reinforcement in high-performance composites, which, due its exceptional properties, becomes an excellent impact absorption material. It has been broadly utilized in aeronautic industry and ballistic protection. In aircrafts, it is mainly used in secondary structures, such as fairings, floor panels, and bullet proof structures in helicopters, whereas, in ballistic protection industry, it is applied in automotive armor and bullet proof vest. Under environmental perspective, it is worrying the development and application of composites, which generate proportional discards of these materials, whether originated from manufacturing process, spare parts or end of life cycle. High-performance composite materials like those using aramid fiber are generally difficult to recycle due to their properties and the difficulty for the separation of the components, making their recycling economically unviable. From the characteristics of composite materials and environmental viewpoint, this paper presents a new aramid fiber recycling process. The main objective of this research was to study different recycling methods in aramid fibers/Neoprene® composites. To promote the Neoprene® degradation, it was used a pyrolysis oven with controlled atmosphere and CO 2 injection. For the degraded separation, it was designed a mechanical washing machine in which the most degraded separation occurred. To complete the materials separation, it was employed a manual cleaning process, and, at least to prove the efficacy of the process, it was applied a tensile test in the yarns.

  13. Recycle PET再生涤纶机织面料的染整工艺探讨%Discussion on Dyeing Process of Recycle PET recycled Polyester Woven Fabrics

    Institute of Scientific and Technical Information of China (English)

    薛以强; 李峻

    2015-01-01

    介绍Recycle PET再生涤纶面料在未来的能源利用和循环经济发展中的前景,着重实验并探讨再生涤纶机织面料的前处理和染色工艺,对其前处理精练退浆剂、分散染料等选择提出有效的实验方法,本文提出一些改善再生涤纶面料在染整过程中的染色均匀性、布面平整、批差等问题,为再生涤纶面料的染整开发提供了一定的实践经验。%Introduce Recycle PET recycled polyester fabric in the future prospects of energy use and economic development cycle, focusing experiment and explore renewable pretreatment and dyeing polyester woven fabric, and propose effective pretreatment scouring desizing agent, disperse dyes and other options for its experimental methods, this paper presents some improvements recycled polyester fabric dyeing process in dyeing uniformity, fabric formation, batch and poor, for the development of recycled polyester fabric dyeing and provide some practical experience.

  14. Valorizing recycled paper sludge by a bioethanol production process with cellulase recycling.

    Science.gov (United States)

    Gomes, Daniel; Domingues, Lucília; Gama, Miguel

    2016-09-01

    The feasibility of cellulase recycling in the scope of bioethanol production from recycled paper sludge (RPS), an inexpensive byproduct with around 39% of carbohydrates, is analyzed. RPS was easily converted and fermented by enzymes and cells, respectively. Final enzyme partition between solid and liquid phases was investigated, the solid-bound enzymes being efficiently recovered by alkaline washing. RPS hydrolysis and fermentation was conducted over four rounds, recycling the cellulases present in both fractions. A great overall enzyme stability was observed: 71, 64 and 100% of the initial Cel7A, Cel7B and β-glucosidase activities, respectively, were recovered. Even with only 30% of fresh enzymes added on the subsequent rounds, solid conversions of 92, 83 and 71% were achieved for the round 2, 3 and 4, respectively. This strategy enabled an enzyme saving around 53-60%, while can equally contribute to a 40% reduction in RPS disposal costs.

  15. Environmental risk related to specific processes during scrap computer recycling and disposal.

    Science.gov (United States)

    Li, Jinhui; Shi, Pixing; Shan, Hongshan; Xie, Yijun

    2012-12-01

    The purpose of this work was to achieve a better understanding of the generation of toxic chemicals related to specific processes in scrap computer recycling and disposal, such as thermal recycling of printed circuit boards (PCBs) and the landfilling or dumping of cathode ray tubes (CRTs). Tube furnace pyrolysis was carried out to simulate different thermal treatment conditions for the identification of the by-products and potential environmental risk from thermal recycling ofPCBs. The Toxicity Characteristic Leaching Procedure (TCLP) and a column test were used to study the leaching characteristics of lead from waste CRT glass, which is one of the most important environmental concerns arising from the disposal of e-waste. The results indicate that more attention should be paid to the benzene series when recycling PCBs under thermal conditions, especially for workers without any personal protection equipment. The impact of immersion on the leaching of lead from CRT leaded glass was more effective than the impact of washing only by acid rain. Thus when waste leaded glass has to be stored for some reason, the storage facility should be dry.

  16. Process Water Recycle in Hydrothermal Liquefaction of Microalgae To Enhance Bio-oil Yield

    NARCIS (Netherlands)

    Ramos-Tercero, E.A.; Bertucco, A.; Brilman, D.W.F.

    2015-01-01

    In this work, the effect of recycling the process water (PW) of hydrothermal liquefaction (HTL) to the HTL reactor was investigated, with the objective being to recover carbon from the organic content of the PW and to develop a solvent-free process. When recycling twice the PW at 220, 240, and 265 °

  17. Consumer recycling: An ethical decision-making process

    DEFF Research Database (Denmark)

    Culiberg, Barbara; Bajde, Domen

    2013-01-01

    and its key concept, that is, moral intensity, which we extend by adding altruism as an important personality trait that influences pro-social behaviour. The data were collected from a sample of 367 adult consumers, representative of the Slovenian population by gender and age. The hypotheses were tested...... using structural equation modelling. The results of our study confirmed the relationships between three key facets of ethical decision making: moral recognition, moral judgment and moral intention. Higher levels of moral recognition were found to lead to more positive moral judgments, which in turn...... makers and social marketers who have to consider not only the consumer characteristics but also the issue characteristics in seeking to understand and influence consumer recycling. Copyright © 2013 John Wiley & Sons, Ltd....

  18. Recycling as an option of used nuclear fuel management strategy

    Energy Technology Data Exchange (ETDEWEB)

    Zagar, Tomaz, E-mail: tomaz.zagar@gen-energija.s [GEN energija, d.o.o., Cesta 4. julija 42, 8270 Krsko (Slovenia); Institute Jozef Stefan, Jamova 39, 1000 Ljubljana (Slovenia); Bursic, Ales; Spiler, Joze [GEN energija, d.o.o., Cesta 4. julija 42, 8270 Krsko (Slovenia); Kim, Dana; Chiguer, Mustapha; David, Gilles; Gillet, Philippe [AREVA, 33 rue La Fayette, 75009 Paris (France)

    2011-04-15

    The paper presents recycling as an option of used nuclear fuel management strategy with specific focus on the Slovenia. GEN energija is an independent supplier of integral and competitive electricity for Slovenia. In response to growing energy needs, GEN has conducted several feasibility and installation studies of a new nuclear power plant in Slovenia. With sustainable development, the environment, and public acceptance in mind, GEN conducted a study with AREVA concerning the options for the management of its' new plant's used nuclear fuel. After a brief reminder of global political and economic context, solutions for used nuclear fuel management using current technologies are presented in the study as well as an economic assessment of a closed nuclear fuel cycle. The paper evaluates and proposes practical solutions for mid-term issues on used nuclear fuel management strategies. Different scenarios for used nuclear fuel management are presented, where used nuclear fuel recycling (as MOX, for mixed oxide fuel, and ERU, for enriched reprocessed uranium) are considered. The study concludes that closing the nuclear fuel cycle will allow Slovenia to have a supplementary fuel supply for its new reactor via recycling, while reducing the radiotoxicity, thermal output, and volume of its wastes for final disposal, reducing uncertainties, gaining public acceptance, and allowing time for capitalization on investments for final disposal.

  19. Solvent recyclability in a multistep direct liquefaction process

    Energy Technology Data Exchange (ETDEWEB)

    Hetland, M.D.; Rindt, J.R. [Univ. of North Dakota, Grand Forks, ND (United States)

    1995-12-31

    Direct liquefaction research at the Energy & Environmental Research Center (EERC) has, for a number of years, concentrated on developing a direct liquefaction process specifically for low-rank coals (LRCs) through the use of hydrogen-donating solvents and solvents similar to coal-derived liquids, the water/gas shift reaction, and lower-severity reaction conditions. The underlying assumption of all of the research was that advantage could be taken of the reactivity and specific qualities of LRCs to produce a tetrahydrofuran (THF)-soluble material that might be easier to upgrade than the soluble residuum produced during direct liquefaction of high-rank coals. A multistep approach was taken to produce the THF-soluble material, consisting of (1) preconversion treatment to prepare the coal for solubilization, (2) solubilization of the coal in the solvent, and (3) polishing to complete solubilization of the remaining material. The product of these three steps can then be upgraded during a traditional hydrotreatment step. The results of the EERC`s research indicated that additional studies to develop this process more fully were justified. Two areas were targeted for further research: (1) determination of the recyclability of the solvent used during solubilization and (2) determination of the minimum severity required for hydrotreatment of the liquid product. The current project was funded to investigate these two areas.

  20. RELATIVE CONTRIBUTIONS OF THE WEAK, MAIN, AND FISSION-RECYCLING r-PROCESS

    Energy Technology Data Exchange (ETDEWEB)

    Shibagaki, S.; Kajino, T. [Department of Astronomy, The University of Tokyo, 113-033 Tokyo (Japan); Mathews, G. J.; Nishimura, S. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo, 181-8588 (Japan); Chiba, S. [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo 152-8550 (Japan); Lorusso, G. [RIKEN Nishina Center, 2-1 Hirosawa, Wako-shi, Saitama 351-0198 (Japan)

    2016-01-10

    There has been a persistent conundrum in attempts to model the nucleosynthesis of heavy elements by rapid neutron capture (the r-process). Although the locations of the abundance peaks near nuclear mass numbers 130 and 195 identify an environment of rapid neutron capture near closed nuclear shells, the abundances of elements just above and below those peaks are often underproduced by more than an order of magnitude in model calculations. At the same time, there is a debate in the literature as to what degree the r-process elements are produced in supernovae or the mergers of binary neutron stars. In this paper we propose a novel solution to both problems. We demonstrate that the underproduction of nuclides above and below the r-process peaks in main or weak r-process models (like magnetohydrodynamic jets or neutrino-driven winds in core-collapse supernovae) can be supplemented via fission fragment distributions from the recycling of material in a neutron-rich environment such as that encountered in neutron star mergers (NSMs). In this paradigm, the abundance peaks themselves are well reproduced by a moderately neutron-rich, main r-process environment such as that encountered in the magnetohydrodynamical jets in supernovae supplemented with a high-entropy, weakly neutron-rich environment such as that encountered in the neutrino-driven-wind model to produce the lighter r-process isotopes. Moreover, we show that the relative contributions to the r-process abundances in both the solar system and metal-poor stars from the weak, main, and fission-recycling environments required by this proposal are consistent with estimates of the relative Galactic event rates of core-collapse supernovae for the weak and main r-process and NSMs for the fission-recycling r-process.

  1. Response to waste electrical and electronic equipments in China: legislation, recycling system, and advanced integrated process.

    Science.gov (United States)

    Zhou, Lei; Xu, Zhenming

    2012-05-01

    Over the past 30 years, China has been suffering from negative environmental impacts from distempered waste electrical and electronic equipments (WEEE) recycling activities. For the purpose of environmental protection and resource reusing, China made a great effort to improve WEEE recycling. This article reviews progresses of three major fields in the development of China's WEEE recycling industry: legal system, formal recycling system, and advanced integrated process. Related laws concerning electronic waste (e-waste) management and renewable resource recycling are analyzed from aspects of improvements and loopholes. The outcomes and challenges for existing formal recycling systems are also discussed. The advantage and deficiency related to advanced integrated recycling processes for typical e-wastes are evaluated respectively. Finally, in order to achieve high disposal rates of WEEE, high-quantify separation of different materials in WEEE and high added value final products produced by separated materials from WEEE, an idea of integrated WEEE recycling system is proposed to point future development of WEEE recycling industry.

  2. Capture of Tritium Released from Cladding in the Zirconium Recycle Process

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, Barry B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Walker, T. B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bruffey, Stephanie H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); DelCul, Guillermo Daniel [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-08-31

    This report is issued as the first revision to FCRD-MRWFD-2016-000297. Zirconium may be recovered from the Zircaloy® cladding of used nuclear fuel (UNF) for recycle or to reduce the quantities of high-level waste destined for a geologic repository. Recovery of zirconium using a chlorination process is currently under development at the Oak Ridge National Laboratory. The approach is to treat the cladding with chlorine gas to convert the zirconium in the alloy (~98 wt % of the alloy mass) to zirconium tetrachloride. A significant fraction of the tritium (0–96%) produced in nuclear fuel during irradiation may be found in zirconium-based cladding and could be released from the cladding when the solid matrix is destroyed by the chlorination reaction. To prevent uncontrolled release of radioactive tritium to other parts of the plant or to the environment, a method to recover the tritium may be required. The focus of this effort was to (1) identify potential methods for the recovery of tritium from the off-gas of the zirconium recycle process, (2) perform scoping tests on selected recovery methods using non-radioactive gas simulants, and (3) select a process design appropriate for testing on radioactive gas streams generated by the engineering-scale zirconium recycle demonstrations on radioactive used cladding.

  3. Technical assessment of processes to enable recycling of low-level contaminated metal waste

    Energy Technology Data Exchange (ETDEWEB)

    Reimann, G.A.

    1991-10-01

    Accumulations of metal waste exhibiting low levels of radioactivity (LLCMW) have become a national burden, both financially and environmentally. Much of this metal could be considered as a resource. The Department of Energy was assigned the task of inventorying and classifying LLCMW, identifying potential applications, and applying and/or developing the technology necessary to enable recycling. One application for recycled LLCMW is high-quality canisters for permanent repository storage of high-level waste (HLW). As many as 80,000 canisters will be needed by 2035. Much of the technology needed to decontaminate LLCMW has already been developed, but no integrated process has been described, even on a pilot scale, for recycling LLCMW into HLW canisters. This report reviews practices for removal of radionuclides and for producing low carbon stainless steel. Contaminants that readily form oxides may be reduced to below de minimis levels and combined with a slag. Most of the radioactivity remaining in the ingot is concentrated in the inclusions. Radionuclides that chemically resemble the elements that comprise stainless steel can not be removed effectively. Slag compositions, current melting practices, and canister fabrication techniques were reviewed.

  4. Assessing the suitability of recycled plastics used as agricultural soil covers: migration study and experimental harvest.

    Science.gov (United States)

    Nerín, C; Batlle, R

    1999-01-01

    The present work is focused on evaluating the suitability of recycling postconsumer agricultural plastic films again for the same use. The criteria to assess the suitability was based on migration study. Both overall and specific migration tests were performed, and the results obtained (ranging from 0.14 to 1.27 mg/dm(2) for overall migration and from not detectable to 6.98 microg/dm(2) for specific migration) show how, from this point of view, the recycled material can be safely proposed to be used again as agricultural soil covers. A theoretical discussion about the migration process is also presented and a simple mathematical model was applied to the data obtained, showing how total migration which is experimentally detected is theoretically predictable. These conclusions found were used to design and develop a controlled crop of tomato by using this recycled film. The use of the recycled plastic in the whole process and the behavior and properties of the pesticides absorbed in the postconsumer film are discussed.

  5. Performance of Recycled Asphalt Pavement as Coarse Aggregate in Concrete

    Directory of Open Access Journals (Sweden)

    Fidelis O. OKAFOR

    2010-12-01

    Full Text Available Recycled asphalt pavement (RAP is the reclaimed and reprocessed pavement material containing asphalt and aggregate. Most RAP is recycled back into pavements, and as a result there is a general lack of data pertaining to the mechanical properties for RAP in other possible applications such as Portland cement concrete. In the present study, some mechanical properties of Portland cement concrete containing RAP as coarse aggregate were investigated in the laboratory. Six concrete mixes of widely differing water/cement ratios and mix proportions were made using RAP as coarse aggregate. The properties tested include the physical properties of the RAP aggregate, the compressive and flexural strengths of the concrete. These properties were compared with those of similar concretes made with natural gravel aggregate. Results of the tests suggest that the strength of concrete made from RAP is dependent on the bond strength of the “asphalt-mortar” (asphalt binder-sand-filler matrix coatings on the aggregates and may not produce concrete with compressive strength above 25 MPa. However, for middle and low strength concrete, the material was found to compare favorably with natural gravel aggregate.

  6. Tire Recycling

    Science.gov (United States)

    1997-01-01

    Cryopolymers, Inc. tapped NASA expertise to improve a process for recycling vehicle tires by converting shredded rubber into products that can be used in asphalt road beds, new tires, hoses, and other products. In conjunction with the Southern Technology Applications Center and Stennis Space Center, NASA expertise in cryogenic fuel-handling needed for launch vehicle and spacecraft operations was called upon to improve the recycling concept. Stennis advised Cryopolymers on the type of equipment required, as well as steps to reduce the amount of liquid nitrogen used in the process. They also guided the company to use more efficient ways to control system hardware. It is estimated that more than 300 million tires nationwide are produced per year. Cryopolymers expects to reach a production rate of 5,000 tires recycled per day.

  7. Enhanced phosphorus removal in the DAF process by flotation scum recycling for advanced treatment of municipal wastewater.

    Science.gov (United States)

    Kwak, Dong-Heui; Lee, Ki-Cheol

    2015-01-01

    To remove phosphorus (P) from municipal wastewater, various types of advanced treatment processes are being actively applied. However, there is commonly a space limit in municipal wastewater treatment plants (MWTPs). For that reason, the dissolved air flotation (DAF), which is well known for small space and flexible application process, is preferred as an additive process to enhance the removal of P. A series of experiments were conducted to investigate the feasibility of flotation scum recycling for effective P removal from a MWTP using a DAF pilot plant over 1 year. The average increases in the removal efficiencies due to flotation scum recycling were 22.6% for total phosphorus (T-P) and 18.3% for PO4-P. A higher removal efficiency of T-P was induced by recycling the flotation scum because a significant amount of Al components remained in the flotation scum. The increase in T-P removal efficiency, due to the recycling of flotation scum, shifted from the boundary of the stoichiometric precipitate to the equilibrium control region. Flotation scum recycling may contribute to improving the quality of treated water and reducing treatment costs by minimizing the coagulant dosage required.

  8. Theoretical and experimental study of foaming process with chain extended recycled PET

    Directory of Open Access Journals (Sweden)

    2009-02-01

    Full Text Available The theoretical and experimental study of a thermoplastic polymer foaming process is presented. Industrial scraps of PET were used for the production of foamed sheets. The process was performed by making use of a chemical blowing agent (CBA in the extrusion process. Due to the low intrinsic viscosity of the recycled PET, a chain extender was also used in order to increase the molecular weight of the polymer matrix. Pyromellitic dianhydride (PMDA and Hydrocerol CT 534 were chosen as chain extender and CBA, respectively. The reactive extrusion and foaming were performed in a two step process. Rheological characterization was carried out on PET samples previously treated with PMDA, as well as the morphological study was performed to define the cellular structure of the foams produced. Moreover, in order to predict the morphology of the foam, a non isothermal model was developed by taking into account both mass transfer phenomenon and viscous forces effect. Model results were compared with experimental data obtained analyzing the foamed samples. The model was validated in relation to working conditions, chemical blowing agent percentage and initial rheological properties of recycled polymer. A pretty good agreement between experimental and calculated data was achieved.

  9. Novel Remanufacturing Process of Recycled Polytetrafluoroethylene(PTFE)/GF Laminate

    Science.gov (United States)

    Xi, Z.; Ghita, O. R.; Johnston, P.; Evans, K. E.

    2011-01-01

    Currently, the PTFE/GF laminate and PTFE PCB manufacturers are under considerable pressure to address the recycling issues due to Waste Electrical and Electronic Equipment (WEEE) Directive, shortage of landfill capacity and cost of disposal. This study is proposing a novel manufacture method for reuse of the mechanical ground PTFE/Glass fibre (GF) laminate and production of the first reconstitute PTFE/GF laminate. The reconstitute PTFE/GF laminate proposed here consists of a layer of recycled sub-sheet, additional layers of PTFE and PTFE coated glass cloth, also covered by copper foils. The reconstitute PTFE/GF laminate showed good dielectric properties. Therefore, there is potential to use the mechanical ground PTFE/GF laminate powder to produce reconstitute PTFE/GF laminate, for use in high frequencies PCB applications.

  10. A novel cleaner production process of citric acid by recycling its treated wastewater.

    Science.gov (United States)

    Xu, Jian; Su, Xian-Feng; Bao, Jia-Wei; Zhang, Hong-Jian; Zeng, Xin; Tang, Lei; Wang, Ke; Zhang, Jian-Hua; Chen, Xu-Sheng; Mao, Zhong-Gui

    2016-07-01

    In this study, a novel cleaner production process of citric acid was proposed to completely solve the problem of wastewater management in citric acid industry. In the process, wastewater from citric acid fermentation was used to produce methane through anaerobic digestion and then the anaerobic digestion effluent was further treated with air stripping and electrodialysis before recycled as process water for the later citric acid fermentation. This proposed process was performed for 10 batches and the average citric acid production in recycling batches was 142.4±2.1g/L which was comparable to that with tap water (141.6g/L). Anaerobic digestion was also efficient and stable in operation. The average chemical oxygen demand (COD) removal rate was 95.1±1.2% and methane yield approached to 297.7±19.8mL/g TCODremoved. In conclusion, this novel process minimized the wastewater discharge and achieved the cleaner production in citric acid industry.

  11. Mineral processing techniques for recycling investment casting shell

    Energy Technology Data Exchange (ETDEWEB)

    Dahlin, Cheryl L.; Nilsen, David N.; Dahlin, David C.; Hunt, Alton H.; Collins, W. Keith

    2002-01-01

    The Albany Research Center of the U.S. Department of Energy used materials characterization and minerals beneficiation methods to separate and beneficially modify spent investment-mold components to identify recycling opportunities and minimize environmentally sensitive wastes. The physical and chemical characteristics of the shell materials were determined and used to guide bench-scale research to separate reusable components by mineral-beneficiation techniques. Successfully concentrated shell materials were evaluated for possible use in new markets.

  12. Recycled construction debris as an aggregates. Production of concrete blocks

    Directory of Open Access Journals (Sweden)

    Sousa, J. G. G.

    2003-12-01

    Full Text Available This paper analyzes the use of recycled construction and demolition debris as aggregate for the construction of concrete blocks to be used in sealing masonry. Initial studies addressed the definition of parameters used in the mix of conventional materials (traditionally used in the production of concrete blocks, involving cylindrical test specimens (100x200 mm, molded with the help of a vibratory table. In addition to these definitions, and based on the mixes showing the best results, a new granulometric range was established, against which the granulometry of the recycled aggregates was adjusted. After the initial studies, concrete blocks were molded with the following dimensions: 100x190x390 mm. Studies have determined the behavior of aggregates in relation to mold humidity specific mass, water absorption, and compression resistance in view of the percentage of recycled debris that composes the total aggregate. For the most part, results suggest that construction and demolition debris can potentially be used in the production of concrete blocks, as well as in other pre-molded artefacts.

    El objetivo de esta investigación es contribuir en la producción de bloques de hormigón para muros de albañilería mediante el aprovechamiento de áridos provenientes del reciclaje de residuos de la construcción civil. Los estudios preliminares tuvieron inicio con la definición de los parámetros de mezcla para los materiales convencionales (tradicionalmente utilizados en la construcción de bloques de hormigón, donde se emplearon probetas cilíndricas (100x200 mm, moldeadas con la ayuda de una mesa vibratoria. Cumplidas estas definiciones, se estableció un rango granulométrico a partir de las composiciones de mejores resultados, donde se buscó ajustar la granulometría de los áridos reciclados. Concluidos los estudios preliminares, se moldearon los bloques de hormigón con dimensiones (100x190x390 mm. Los estudios presentan como resultado el

  13. Recycling of iron foundry sand and glass waste as raw material for production of whiteware.

    Science.gov (United States)

    Bragança, Saulo R; Vicenzi, Juliane; Guerino, Kareline; Bergmann, Carlos P

    2006-02-01

    The purpose of this study was to evaluate the production feasibility of triaxial whiteware using sand from cast iron moulds as a raw material instead of silica, and recycled glass in place of feldspar. Formulations were prepared using sand, glass waste, and white-firing clay such that only 50% of the composition was virgin material (clay). The ceramic bodies were formed by pressing and fired at different temperatures (between 1100 and 1300 degrees C). Specimens were characterized in terms of green density prior to firing; and their flexural strength, linear shrinkage, and water absorption were measured after firing. The microstructure was determined by scanning electron microscopy. Possible environmental impacts of this recycling process were also evaluated, through solubility and leaching tests, according to Brazilian standards. Gaseous emissions during the firing process were also analysed. The results showed that it is possible to produce triaxial ceramics by using such alternative raw materials.

  14. Biomass recycle as a means to improve the energy efficiency of CELSS algal culture systems

    Science.gov (United States)

    Radmer, R.; Cox, J.; Lieberman, D.; Behrens, P.; Arnett, K.

    1987-01-01

    Algal cultures can be very rapid and efficient means to generate biomass and regenerate the atmosphere for closed environmental life support systems. However, as in the case of most higher plants, a significant fraction of the biomass produced by most algae cannot be directly converted to a useful food product by standard food technology procedures. This waste biomass will serve as an energy drain on the overall system unless it can be efficiently recycled without a significant loss of its energy content. Experiments are reported in which cultures of the alga Scenedesmus obliquus were grown in the light and at the expense of an added carbon source, which either replaced or supplemented the actinic light. As part of these experiments, hydrolyzed waste biomass from these same algae were tested to determine whether the algae themselves could be made part of the biological recycling process. Results indicate that hydrolyzed algal (and plant) biomass can serve as carbon and energy sources for the growth of these algae, suggesting that the efficiency of the closed system could be significantly improved using this recycling process.

  15. Evaluation of a recycling process for printed circuit board by physical separation and heat treatment.

    Science.gov (United States)

    Fujita, Toyohisa; Ono, Hiroyuki; Dodbiba, Gjergj; Yamaguchi, Kunihiko

    2014-07-01

    Printed circuit boards (PCBs) from discarded personal computer (PC) and hard disk drive were crushed by explosion in water or mechanical comminution in order to disintegrate the attached parts. More parts were stripped from PCB of PC, composed of epoxy resin; than from PCB of household appliance, composed of phenol resin. In an attempt to raise the copper grade of PCB by removing other components, a carbonization treatment was investigated. The crushed PCB without surface-mounted parts was carbonized under a nitrogen atmosphere at 873-1073 K. After screening, the char was classified by size into oversized pieces, undersized pieces and powder. The copper foil and glass fiber pieces were liberated and collected in undersized fraction. The copper foil was liberated easily from glass fiber by stamping treatment. As one of the mounted parts, the multi-layered ceramic capacitors (MLCCs), which contain nickel, were carbonized at 873 K. The magnetic separation is carried out at a lower magnetic field strength of 0.1T and then at 0.8 T. In the +0.5mm size fraction the nickel grade in magnetic product was increased from 0.16% to 6.7% and the nickel recovery is 74%. The other useful mounted parts are tantalum capacitors. The tantalum capacitors were collected from mounted parts. The tantalum-sintered bodies were separated from molded resins by heat treatment at 723-773 K in air atmosphere and screening of 0.5mm. Silica was removed and 70% of tantalum grade was obtained after more than 823K heating and separation. Next, the evaluation of Cu recycling in PCB is estimated. Energy consumption of new process increased and the treatment cost becomes 3 times higher comparing the conventional process, while the environmental burden of new process decreased comparing conventional process. The nickel recovery process in fine ground particles increased energy and energy cost comparing those of the conventional process. However, the environmental burden decreased than the conventional

  16. Quantification of re-absorption and re-emission processes to determine photon recycling efficiency in perovskite single crystals

    Science.gov (United States)

    Fang, Yanjun; Wei, Haotong; Dong, Qingfeng; Huang, Jinsong

    2017-02-01

    Photon recycling, that is, iterative self-absorption and re-emission by the photoactive layer itself, has been speculated to contribute to the high open-circuit voltage in several types of high efficiency solar cells. For organic-inorganic halide perovskites that have yielded highly efficient photovoltaic devices, however, it remains unclear whether the photon recycling effect is significant enough to improve solar cell efficiency. Here we quantitatively evaluate the re-absorption and re-emission processes to determine photon recycling efficiency in hybrid perovskite with its single crystals by measuring the ratio of the re-emitted photons to the initially excited photons, which is realized by modulating their polarization to differentiate them. The photon recycling efficiencies are revealed to be less than 0.5% in CH3NH3PbI3 and CH3NH3PbBr3 single crystals under excitation intensity close to one sun, highlighting the intrinsically long carrier recombination lifetime instead of the photon-recycling-induced photon propagation as the origin of their long carrier diffusion length.

  17. Waste Treatment Technology Process Development Plan For Hanford Waste Treatment Plant Low Activity Waste Recycle

    Energy Technology Data Exchange (ETDEWEB)

    McCabe, Daniel J.; Wilmarth, William R.; Nash, Charles A.

    2013-08-29

    treatment, disposition of the decontaminated Recycle stream may be suitable for the Effluent Treatment Facility, where it could be evaporated and solidified. The contaminated slurry stream containing the absorbents and radionuclides will be preliminarily characterized in this phase of the program to evaluate disposal options, and disposition routes will be tested in the next phase. The testing described herein will aid in selection of the best disposal pathway. Several research tasks have been identified that are needed for this initial phase: imulant formulation- Concentration of Recycle to reduce storage volume; Blending of concentrated Recycle with tank waste; Sorption of radionuclides; Precipitation of radionuclides. After this initial phase of testing, additional tasks are expected to be identified for development. These tasks likely include evaluation and testing of applicable solid-liquid separation technologies, slurry rheology measurements, composition variability testing and evaluations, corrosion and erosion testing, slurry storage and immobilization investigations, and decontaminated Recycle evaporation and solidification. Although there are a number of unknown parameters listed in the technical details of the concepts described here, many of these parameters have precedence and do not generally require fundamental new scientific breakthroughs. Many of the materials and processes described are already used in radioactive applications in the DOE complex, or have been tested previously in comparable conditions. Some of these materials and equipment are already used in High Level Waste applications, which are much more complex and aggressive conditions than the LAW Recycle stream. In some cases, the unknown parameters are simply extensions of already studied conditions, such as tank waste corrosion chemistry. The list of testing needs at first appears daunting, but virtually all have been done before, although there are potential issues with compatibility with this

  18. Optimization of the ethanol recycling reflux extraction process for saponins using a design space approach.

    Science.gov (United States)

    Gong, Xingchu; Zhang, Ying; Pan, Jianyang; Qu, Haibin

    2014-01-01

    A solvent recycling reflux extraction process for Panax notoginseng was optimized using a design space approach to improve the batch-to-batch consistency of the extract. Saponin yields, total saponin purity, and pigment yield were defined as the process critical quality attributes (CQAs). Ethanol content, extraction time, and the ratio of the recycling ethanol flow rate and initial solvent volume in the extraction tank (RES) were identified as the critical process parameters (CPPs) via quantitative risk assessment. Box-Behnken design experiments were performed. Quadratic models between CPPs and process CQAs were developed, with determination coefficients higher than 0.88. As the ethanol concentration decreases, saponin yields first increase and then decrease. A longer extraction time leads to higher yields of the ginsenosides Rb1 and Rd. The total saponin purity increases as the ethanol concentration increases. The pigment yield increases as the ethanol concentration decreases or extraction time increases. The design space was calculated using a Monte-Carlo simulation method with an acceptable probability of 0.90. Normal operation ranges to attain process CQA criteria with a probability of more than 0.914 are recommended as follows: ethanol content of 79-82%, extraction time of 6.1-7.1 h, and RES of 0.039-0.040 min-1. Most of the results of the verification experiments agreed well with the predictions. The verification experiment results showed that the selection of proper operating ethanol content, extraction time, and RES within the design space can ensure that the CQA criteria are met.

  19. Optimization of the ethanol recycling reflux extraction process for saponins using a design space approach.

    Directory of Open Access Journals (Sweden)

    Xingchu Gong

    Full Text Available A solvent recycling reflux extraction process for Panax notoginseng was optimized using a design space approach to improve the batch-to-batch consistency of the extract. Saponin yields, total saponin purity, and pigment yield were defined as the process critical quality attributes (CQAs. Ethanol content, extraction time, and the ratio of the recycling ethanol flow rate and initial solvent volume in the extraction tank (RES were identified as the critical process parameters (CPPs via quantitative risk assessment. Box-Behnken design experiments were performed. Quadratic models between CPPs and process CQAs were developed, with determination coefficients higher than 0.88. As the ethanol concentration decreases, saponin yields first increase and then decrease. A longer extraction time leads to higher yields of the ginsenosides Rb1 and Rd. The total saponin purity increases as the ethanol concentration increases. The pigment yield increases as the ethanol concentration decreases or extraction time increases. The design space was calculated using a Monte-Carlo simulation method with an acceptable probability of 0.90. Normal operation ranges to attain process CQA criteria with a probability of more than 0.914 are recommended as follows: ethanol content of 79-82%, extraction time of 6.1-7.1 h, and RES of 0.039-0.040 min-1. Most of the results of the verification experiments agreed well with the predictions. The verification experiment results showed that the selection of proper operating ethanol content, extraction time, and RES within the design space can ensure that the CQA criteria are met.

  20. Recycling of sludge with the Aqua Reci process.

    Science.gov (United States)

    Stendahl, K; Jäfverström, S

    2004-01-01

    Supercritical Water Oxidation (SCWO) is an innovative and effective destruction method for organics in sewage sludge. The SCWO process leaves a slurry of inorganic ash in a pure water phase free from organic contaminants, which opens possibilities for a simple process to recover components like phosphates and/or coagulants from the sewage sludge, a process marketed as the Aqua Reci. In a continuous pilot plant for the SCWO process digested sludge has been treated. The ash has been extracted in lab- and pilot scale with both caustic and acids in order to recover phosphates and coagulants. The particle size of the inorganic contaminants in the water after the SCWO process is between 1-10 microm, which means that it is very reactive. The phosphate, and partly the aluminium, can be extracted with caustic as iron and heavy metals are completely insoluble in caustic. This is a method to separate the phosphates from the rest of the contaminants. However, high calcium content will bind the phosphate as calcium phosphate insoluble in caustic. In most cases the calcium content is too high and the best solution is to dissolve phosphates and all metals with sulphuric acid. From this solution first iron phosphate can be separated and thereafter in a second step aluminium and finally heavy metals in a third step. Iron can be separated from the phosphate, either by leaching the phosphate with caustic off to sodium phosphate leaving a precipitate consisting of iron hydroxide, or the iron phosphate can be dissolved in hydrochloric acid followed by a liquid extraction process where ferric chloride can be separated leaving a phosphoric acid. By the acid dissolving process it is possible to recover phosphate, iron, aluminium, and heavy metals from the inorganic since the Aqua Reci process only leaves a silica residue representing about 10% of the DS content in the original sludge.

  1. Hanford recycling

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, I.M.

    1996-09-01

    DOE recycling contract at the Hanford site and a central group to control the contract. 0 Using a BOA or MTS contract as a way to get proceeds from recycling back to site facilities to provide incentives for recycling. . Upgrading tracking mechanisms to track and recycle construction waste which is presently buried in onsite pits. . Establishing contract performance measures which hold each project accountable for specific waste reduction goals. * Recycling and reusing any material or equipment possible as buildings are dismantled.

  2. Recycling of AZ40 Magnesium Alloy Scraps by Hydriding-Dehydriding and Subsequent Consolidation Processing

    Science.gov (United States)

    Haiping, Zhou; Lianxi, Hu; Yu, Sun; Heng, Wang

    2015-09-01

    The hydriding-dehydriding process was used to recycle AZ40 magnesium (Mg) alloy scraps, and the microstructure nanocrystallization was realized. X-ray diffraction analysis, scanning electron microscopy, and transmission electron microscopy were carried out to characterize the microstructure. After mechanically milling in hydrogen for 72 h, matrix Mg was completely turned into nanocrystalline MgH2, with an average crystallite size of about 10 nm. And then, the MgH2 phase was completely transformed into Mg again through vacuum dehydriding treatment at 300 °C for 192 min, with an average crystallite size of about 20 nm. In addition, the nanocrystalline alloy powders were hot-pressed and extruded into bars. The average grain size of the bars was about 500 nm, which had reached the size of ultrafine-grain. Meanwhile, the yield strength and ultimate tensile strength of the as-extruded bars reached about 312 and 497 MPa, respectively. The results indicate that hydriding-dehydriding process is a feasible method for recycling of Mg alloy scraps, and it is expected to have a good application prospect in preparing ultrafine-grain Mg alloys.

  3. Spark Plasma Sintering As a Solid-State Recycling Technique: The Case of Aluminum Alloy Scrap Consolidation

    Directory of Open Access Journals (Sweden)

    Dimos Paraskevas

    2014-08-01

    Full Text Available Recently, “meltless” recycling techniques have been presented for the light metals category, targeting both energy and material savings by bypassing the final recycling step of remelting. In this context, the use of spark plasma sintering (SPS is proposed in this paper as a novel solid-state recycling technique. The objective is two-fold: (I to prove the technical feasibility of this approach; and (II to characterize the recycled samples. Aluminum (Al alloy scrap was selected to demonstrate the SPS effectiveness in producing fully-dense samples. For this purpose, Al alloy scrap in the form of machining chips was cold pre-compacted and sintered bellow the solidus temperature at 490 °C, under elevated pressure of 200 MPa. The dynamic scrap compaction, combined with electric current-based joule heating, achieved partial fracture of the stable surface oxides, desorption of the entrapped gases and activated the metallic surfaces, resulting in efficient solid-state chip welding eliminating residual porosity. The microhardness, the texture, the mechanical properties, the microstructure and the density of the recycled specimens have been investigated. An X-ray computed tomography (CT analysis confirmed the density measurements, revealing a void-less bulk material with homogeneously distributed intermetallic compounds and oxides. The oxide content of the chips incorporated within the recycled material slightly increases its elastic properties. Finally, a thermal distribution simulation of the process in different segments illustrates the improved energy efficiency of this approach.

  4. Processing and properties of a solid energy fuel from municipal solid waste (MSW) and recycled plastics.

    Science.gov (United States)

    Gug, JeongIn; Cacciola, David; Sobkowicz, Margaret J

    2015-01-01

    Diversion of waste streams such as plastics, woods, papers and other solid trash from municipal landfills and extraction of useful materials from landfills is an area of increasing interest especially in densely populated areas. One promising technology for recycling municipal solid waste (MSW) is to burn the high-energy-content components in standard coal power plant. This research aims to reform wastes into briquettes that are compatible with typical coal combustion processes. In order to comply with the standards of coal-fired power plants, the feedstock must be mechanically robust, free of hazardous contaminants, and moisture resistant, while retaining high fuel value. This study aims to investigate the effects of processing conditions and added recyclable plastics on the properties of MSW solid fuels. A well-sorted waste stream high in paper and fiber content was combined with controlled levels of recyclable plastics PE, PP, PET and PS and formed into briquettes using a compression molding technique. The effect of added plastics and moisture content on binding attraction and energy efficiency were investigated. The stability of the briquettes to moisture exposure, the fuel composition by proximate analysis, briquette mechanical strength, and burning efficiency were evaluated. It was found that high processing temperature ensures better properties of the product addition of milled mixed plastic waste leads to better encapsulation as well as to greater calorific value. Also some moisture removal (but not complete) improves the compacting process and results in higher heating value. Analysis of the post-processing water uptake and compressive strength showed a correlation between density and stability to both mechanical stress and humid environment. Proximate analysis indicated heating values comparable to coal. The results showed that mechanical and moisture uptake stability were improved when the moisture and air contents were optimized. Moreover, the briquette

  5. Recycling Waste Bakelite As A Carbon Resource In Ironmaking

    Directory of Open Access Journals (Sweden)

    James Ransford Dankwah

    2015-02-01

    Full Text Available Abstract Bakelite is a 3-dimensional cross-linked network structured thermosetting polymer which is difficult to recycle after use. However it contains high levels of carbon and CaCO3 that can be recovered for use as reductant and fluxing agent in ironmaking. In this work we report the use of post-consumer bakelite as reductant for the production of metallic iron from iron oxide in a horizontal tube furnace through the composite pellet approach.Gas emission studies were conducted by pyrolysing raw bakelite at different temperatures within the temperature range 1200-1600 C in a horizontal tube furnace. Following thiscomposite pellets were then formed from mixtures of iron oxide and post-consumer bakelite.The iron oxide-bakelite composites were heated from room temperature to 1200 C and then between 1200-1600 C in a continuous stream of pure argon and the off gas was analysed continuously using an infrared IR gas analyser. Elemental analyses of samples of the reduced metal were performed chemically for its oxygen content using a LECO oxygennitrogen analyser. The extent of reduction after ten minutes was determined from the oxygen content. Gas emission studies revealed the emission of large volumes of the reductant gases CO and CH4along with CO2.It is further demonstrated that post-consumer bakelite is effective at reducing iron oxide to produce metallic iron.

  6. Process for the recycling of alkaline and zinc-carbon spent batteries

    Science.gov (United States)

    Ferella, Francesco; De Michelis, Ida; Vegliò, Francesco

    In this paper a recycling process for the recovery of zinc and manganese from spent alkaline and zinc-carbon batteries is proposed. Laboratory tests are performed to obtain a purified pregnant solution from which metallic zinc (purity 99.6%) can be recovered by electrolysis; manganese is recovered as a mixture of oxides by roasting of solid residue coming from the leaching stage. Nearly 99% of zinc and 20% of manganese are extracted after 3 h, at 80 °C with 10% w/v pulp density and 1.5 M sulphuric acid concentration. The leach liquor is purified by a selective precipitation of iron, whereas metallic impurities, such as copper, nickel and cadmium are removed by cementation with zinc powder. The solid residue of leaching is roasted for 30 min at 900 °C, removing graphite completely and obtaining a mixture of Mn 3O 4 and Mn 2O 3 with 70% grade of Mn. After that a technical-economic assessment is carried out for a recycling plant with a feed capacity of 5000 t y -1 of only alkaline and zinc-carbon batteries. This analysis shows the economic feasibility of that plant, supposing a battery price surcharge of 0.5 € kg -1, with a return on investment of 34.5%, gross margin of 35.8% and around 3 years payback time.

  7. Caustic Recycle from Hanford Tank Waste Using NaSICON Ceramic Membrane Salt Splitting Process

    Energy Technology Data Exchange (ETDEWEB)

    Fountain, Matthew S.; Kurath, Dean E.; Sevigny, Gary J.; Poloski, Adam P.; Pendleton, J.; Balagopal, S.; Quist, M.; Clay, D.

    2009-02-20

    A family of inorganic ceramic materials, called sodium (Na) Super Ion Conductors (NaSICON), has been studied at Pacific Northwest National Laboratory (PNNL) to investigate their ability to separate sodium from radioactively contaminated sodium salt solutions for treating U.S. Department of Energy (DOE) tank wastes. Ceramatec Inc. developed and fabricated a membrane containing a proprietary NAS-GY material formulation that was electrochemically tested in a bench-scale apparatus with both a simulant and a radioactive tank-waste solution to determine the membrane performance when removing sodium from DOE tank wastes. Implementing this sodium separation process can result in significant cost savings by reducing the disposal volume of low-activity wastes and by producing a NaOH feedstock product for recycle into waste treatment processes such as sludge leaching, regenerating ion exchange resins, inhibiting corrosion in carbon-steel tanks, or retrieving tank wastes.

  8. Hydrogen Decrepitation Press-Less Process Recycling of NdFeB sintered magnets

    DEFF Research Database (Denmark)

    Xia, Manlong; Abrahamsen, Asger Bech; Bahl, Christian;

    2017-01-01

    in a graphite mold. Coercivities up to 534 kA/m were obtained in porous samples based on powder size d milling step resulted in full density isotropic magnets for d > 100 μm. The coercivity reached Hci = 957 kA/m being 86 % of the original N48M material without addition of rare earth......A Hydrogen Decrepitation Press-Less Process (HD-PLP) recycling method for recycling of anisotropic NdFeB magnets is demonstrated. The method combines hydrogen decrepitation (HD) disintegration of the initial magnet, powder sieving and the Press-Less Process (PLP), where hydride powder is sintered...

  9. Design of a lamella settler for biomass recycling in continuous ethanol fermentation process.

    Science.gov (United States)

    Tabera, J; Iznaola, M A

    1989-04-20

    The design and application of a settler to a continuous fermentation process with yeast recycle were studied. The compact lamella-type settler was chosen to avoid large volumes associated with conventional settling tanks. A rationale of the design method is covered. The sedimentation area was determined by classical batch settling rate tests and sedimentation capacity calculation. Limitations on the residence time of the microorganisms in the settler, rather than sludge thickening considerations, was the approach employed for volume calculation. Fermentation rate tests with yeast after different sedimentation periods were carried out to define a suitable residence time. Continuous cell recycle fermentation runs, performed with the old and new sedimentation devices, show that lamella settler improves biomass recycling efficiency, being the process able to operate at higher sugar concentrations and faster dilution rates.

  10. Analytic estimation of recycled products added value as a means for effective environmental management

    Science.gov (United States)

    Batzias, Dimitris F.

    2012-12-01

    In this work, we present an analytic estimation of recycled products added value in order to provide a means for determining the degree of recycling that maximizes profit, taking also into account the social interest by including the subsidy of the corresponding investment. A methodology has been developed based on Life Cycle Product (LCP) with emphasis on added values H, R as fractions of production and recycle cost, respectively (H, R >1, since profit is included), which decrease by the corresponding rates h, r in the recycle course, due to deterioration of quality. At macrolevel, the claim that "an increase of exergy price, as a result of available cheap energy sources becoming more scarce, leads to less recovered quantity of any recyclable material" is proved by means of the tradeoff between the partial benefits due to material saving and resources degradation/consumption (assessed in monetary terms).

  11. Poultry feather wastes recycling possibility as soil nutrient

    Directory of Open Access Journals (Sweden)

    Lili Mézes

    2015-10-01

    Full Text Available Poultry feathers are produced in large amounts as a waste in poultry slaughterhouses. Only 60-70% of the poultry slaughterhouse products are edible for human being. This means more million tons annually worldwide (Papadopoulus et al., 1986; Williams et al., 1991; Hegedűs et al., 1998. The keratin-content of feather can be difficulty digested, so physical, chemical and/or biological pre-treatment are needed in practice, which have to be set according to the utilization method. Feather was enzymatic degraded, and then fermented in separated bioreactors. The anaerobic bioreactor system (4 digesters with 6 litre volume was controlled by ACE SCADA software running on Linux platforms. Pot scale seed germination tests were established to suggest the quantity of digested slurry to be utilized. The chosen test plants were lettuce (Lactuca sativa. In case of reproduction test Student’s t-test was applied to examine significant differences between the root lengths of the control and the treated plant species. In case of pot seed germination variance analysis with Tukey B’s and Duncan test was applied to examine significant differences between the root lengths of plants, grown on different treatments. The effect of treatments on germination ability of the plant species was expressed in the percentage of the controls. According to Student’s t-test significant difference was found between root lengths of different treatments. Based on variance analysis with Tukey B’s and Duncan tests could be detected a significant difference between the treatments. Utilization of the fermented material reduces the use of fertilizers and because of its large moisture content it reduces the watering costs. Recycle of the slaughterhouse feather and different agricultural wastes and by-products can solve three main problems: disposal of harmful materials, producing of renewable energy and soil nutrient, measuring reflectance at the certain spectral range, which can

  12. Pretreatment of lignocellulose with biological acid recycling (the Biosulfurol process)

    NARCIS (Netherlands)

    Groenestijn, van J.; Hazewinkel, O.; Bakker, R.R.C.

    2006-01-01

    A biomass pretreatment process is being developed based on contacting lignocellulosic biomass with 70% sulfuric acid and subsequent hydrolysis by adding water. In this process, the hydrolysate can be fermented yielding ethanol, while the sulfuric acid is partly recovered by anion-selective membranes

  13. Modeling Recycling Asphalt Pavement Processing Technologies in Asphalt Mixing Plants

    OpenAIRE

    Simonas Tamaliūnas; Henrikas Sivilevičius

    2011-01-01

    The article presents reclaimed asphalt pavement (RAP) processing technologies and equipment models used in the asphalt mixing plant (AMP). The schematic model indicating all possible ways to process RAP in AMP is shown. The model calculating the needed temperature of mineral materials used for heating RAP is given and an example of such calculation is provided.Article in Lithuanian

  14. Modeling Recycling Asphalt Pavement Processing Technologies in Asphalt Mixing Plants

    Directory of Open Access Journals (Sweden)

    Simonas Tamaliūnas

    2011-04-01

    Full Text Available The article presents reclaimed asphalt pavement (RAP processing technologies and equipment models used in the asphalt mixing plant (AMP. The schematic model indicating all possible ways to process RAP in AMP is shown. The model calculating the needed temperature of mineral materials used for heating RAP is given and an example of such calculation is provided.Article in Lithuanian

  15. Triple Recycling Processes Impact Systemic and Local Bioavailability of Orally Administered Flavonoids.

    Science.gov (United States)

    Dai, Peimin; Zhu, Lijun; Luo, Feifei; Lu, Linlin; Li, Qiang; Wang, Liping; Wang, Ying; Wang, Xinchun; Hu, Ming; Liu, Zhongqiu

    2015-05-01

    Triple recycling (i.e., enterohepatic, enteric and local recycling) plays a central role in governing the disposition of phenolics such as flavonoids, resulting in low systemic bioavailability but higher gut bioavailability and longer than expected apparent half-life. The present study aims to investigate the coexistence of these recycling schemes using model bioactive flavonoid tilianin and a four-site perfused rat intestinal model in the presence or absence of a lactase phlorizin hydrolase (LPH) inhibitor gluconolactone and/or a glucuronidase inhibitor saccharolactone. The result showed that tilianin could be metabolized into tilianin glucuronide, acacetin, and acacetin glucuronide, which are excreted into the bile and luminal perfusate (highest in the duodenum and lowest in the colon). Gluconolactone (20 mM) significantly reduced the absorption of tilianin and the enteric and biliary excretion of acacetin glucuronide. Saccharolactone (0.1 mM) alone or in combination of gluconolactone also remarkably reduced the biliary and intestinal excretion of acacetin glucuronide. Acacetin glucuronides from bile or perfusate were rapidly hydrolyzed by bacterial β-glucuronidases to acacetin, enabling enterohepatic and enteric recycling. Moreover, saccharolactone-sensitive tilianin disposition and glucuronide deconjugation, which was more active in the small intestine than the colon, points to the small intestinal origin of the deconjugation enzyme and supports the presence of local recycling scheme. In conclusion, our studies have demonstrated triple recycling of a bioactive phenolic (i.e., a model flavonoid), and this recycling may have an impact on the site and duration of polyphenols pharmacokinetics in vivo.

  16. TORBED process reactor technology for asphalt paving recycle

    Energy Technology Data Exchange (ETDEWEB)

    Wellwood, G. A. [Torftech Limited, Reading (United Kingdom); Laughlin, R. G. [Torftech Canada Inc., Mississauga, ON (Canada)

    2001-07-01

    Fundamental principles underlying the TORBED reactor technologies are reviewed. Advantages, limitations, and the experience gained in applying the reactor to a range of material processing needs, particularly reprocessing asphalt paving waste, are discussed. The TORBED reactor consists of a compact shallow packed bed of particles suspended above an annular ring of stationary blades through which a process gas stream is passed at high velocity. Unlike fluidized beds, the process gas mass flow can be set to suit the process, i. e. a smaller gas mass flow can be used at a higher velocity at exit from the blades to keep the bed in proper motion. Advantages are: (1) smaller reactor size with rapid start-up and program change, (2) faster and more precise processing of particles, resulting in a consistent product or process, (3) low process stream pressure losses which facilitate process gas recirculation, (4) ability to process widely graded and irregularly shaped feed stocks, and (5) simplicity of operation through real time control. The 'expanded' version of the TORBED reactor also permits fuel injection to generate process gas temperatures in excess of 1600 degrees C, and allows high gas flow rates with low pressure drop. When used to reprocess asphalt paving waste, the coal tar, used in some 25 per cent of existing roads in the Netherlands, can be easily removed and destroyed and the cleaned stone and the energy generated form the destruction of the coal tar, can be reused in creating new bitumen- containing asphalt paving. Excellent results are reported to have been obtained in pilot studies. Pilot trial also have been conducted on the combustion of wood waste for power generation, with encouraging results. Other pilot projects addressed alternative cementitious materials. 5 refs.

  17. 废弃硒鼓资源化技术研究%Processing of Waste Toner Cartridge Recycling

    Institute of Scientific and Technical Information of China (English)

    黄庆; 王景伟; 王鹏程; 邓毅

    2014-01-01

    Toner cartridge as the key component is widely used in laser printer, photocopier and fax machine. As the quantity of discard toner cartridge is increasing year by year, recycling of waste toner cartridge has attracted domestic and international attention. The material composition of waste toner cartridge is introduced, as well as the available recycling of waste toner cartridge and the environ-mental hazard caused by the toners which remained in the cartridge. Simultaneously, processes and technologies applied in waste toner cartridge recycling by domestic and international are summarized. Accordingly, the potential problems existing in waste toner cartridge recycling technologies are discussed, and constructive suggestions for improvement of recycling technology in the future are provided.%硒鼓作为核心部件被广泛应用于激光打印机、复印机和传真机中。随着硒鼓的报废量逐年增大,废弃硒鼓的无害化处理和资源化利用越来越受到人们的关注。主要介绍了废弃硒鼓的材料组分、可资源化性和残留墨粉的环境危害性,总结了国内外废弃硒鼓资源化技术和特点,并提出了废弃硒鼓资源化技术中存在的问题,为未来废弃硒鼓资源化技术的改进提供建设性意见。

  18. Fractionation and fluxes of metals and radionuclides during the recycling process of phosphogypsum wastes applied to mineral CO2 sequestration

    OpenAIRE

    Contreras Llanes, Manuel; Pérez López, Rafael; Gázquez González, Manuel Jesús; Morales Flórez, V.; Santos, A; Esquivias, L.; Bolívar Raya, Juan Pedro

    2015-01-01

    The industry of phosphoric acid produces a calcium-rich by-product known as phosphogypsum, which is usually stored in large stacks of millions of tons. Up to now, no commercial application has been widely implemented for its reuse because of the significant presence of potentially toxic contaminants. This work confirmed that up to 96% of the calcium of phosphogypsum could be recycled for CO2 mineral sequestration by a simple two-step process: alkaline dissolution and aqueous carbonation, unde...

  19. A Study of Recycling Operation Process from the Waste Selective Collection of Itu/SP City

    Directory of Open Access Journals (Sweden)

    Délvio Venanzi

    2015-06-01

    Full Text Available This present work is the result of a survey in a solid waste sorting area COMAREI - Cooperative of Recyclable Materials in the city of Itu. Due to the unbridled consumption and increase in the amount of household waste, cooperatives have the need for improvement in their separation processes and disposal of such waste. New techniques allow to process more material and to accelerate the process of collecting and allocating a larger amount of material. The objective of this study was to analyse the overall functioning of the Cooperative screening system. The methodology was field research with visits to monitor the workflow of employees, their observation procedures and spontaneous conversations with members, as well as bibliographic research and collection of secondary data. As a result it can be observed that the cooperative members have difficulty in screening, because the population does not rule out the material properly; preventing a better use of time and result in the screening process. The operation of the semi-mechanized system works with the separation of seven types of waste, of which only five of these are guaranteed marketing.

  20. Rapid Automated Dissolution and Analysis Techniques for Radionuclides in Recycle Process Streams

    Energy Technology Data Exchange (ETDEWEB)

    Sudowe, Ralf [Univ. of Nevada, Las Vegas, NV (United States). Radiochemistry Program and Health Physics Dept.; Roman, Audrey [Univ. of Nevada, Las Vegas, NV (United States). Radiochemistry Program; Dailey, Ashlee [Univ. of Nevada, Las Vegas, NV (United States). Radiochemistry Program; Go, Elaine [Univ. of Nevada, Las Vegas, NV (United States). Radiochemistry Program

    2013-07-18

    The analysis of process samples for radionuclide content is an important part of current procedures for material balance and accountancy in the different process streams of a recycling plant. The destructive sample analysis techniques currently available necessitate a significant amount of time. It is therefore desirable to develop new sample analysis procedures that allow for a quick turnaround time and increased sample throughput with a minimum of deviation between samples. In particular, new capabilities for rapid sample dissolution and radiochemical separation are required. Most of the radioanalytical techniques currently employed for sample analysis are based on manual laboratory procedures. Such procedures are time- and labor-intensive, and not well suited for situations in which a rapid sample analysis is required and/or large number of samples need to be analyzed. To address this issue we are currently investigating radiochemical separation methods based on extraction chromatography that have been specifically optimized for the analysis of process stream samples. The influence of potential interferences present in the process samples as well as mass loading, flow rate and resin performance is being studied. In addition, the potential to automate these procedures utilizing a robotic platform is evaluated. Initial studies have been carried out using the commercially available DGA resin. This resin shows an affinity for Am, Pu, U, and Th and is also exhibiting signs of a possible synergistic effects in the presence of iron.

  1. Relative contributions of the weak, main and fission-recycling r-process

    CERN Document Server

    Shibagaki, S; Mathews, G J; Chiba, S; Nishimura, S; Lorusso, G

    2015-01-01

    There has been a persistent conundrum in attempts to model the nucleosynthesis of heavy elements by rapid neutron capture (the $r$-process). Although the location of the abundance peaks near nuclear mass numbers 130 and 195 identify an environment of rapid neutron capture near closed nuclear shells, the abundances of elements just above and below those peaks are often underproduced by more than an order of magnitude in model calculations. At the same time there is a debate in the literature as to what degree the $r$-process elements are produced in supernovae or the mergers of binary neutron stars. In this paper we propose a novel solution to both problems. We demonstrate that the underproduction of elements above and below the $r$-process peaks characteristic in the main or weak $r$-process events (like magnetohydrodynamic jets or neutrino-driven winds in core-collapse supernovae) can be supplemented via fission fragment distributions from the recycling of material in a neutron-rich environment such as that ...

  2. Preliminary Study on the Performance and Interaction of Recycling Hydrolytic-Aerobic Combined Process of High Concentration Starch Wastewater

    Institute of Scientific and Technical Information of China (English)

    李清彪; 廖鑫凯; 吴志旺; 邓旭; 黄益丽; 卢英华; 孙道华; 洪铭媛; 王琳

    2004-01-01

    A new recycling hydrolytic-aerobic combined process was developed to treat the high concentration organic wastewater. Simulated wastewater containing 10 g·L-1 starch with a CODcr value of 10000 mg·L-1 wasused. At first, the hydrolytic degradation and aerobic degradation process were examined in two batch reactors, respectively. In the stand-alone hydrolytic process, starch in the wastewater almost disappeared after 11 h treatment, but CODCr remained as high as 5803mg·L-1 after two days. In the aerobic process, the biodegradation rate of starch was much slower during the first 11 h than that in the hydrolytic process, although the CODCr removal efficiency reached 89.6% and more than 90% starch could be degraded after 37.5 h. To determine the interaction effects of the two processes, a series of hydrolytic-aerobic combinations were examined in details. Hydrolytic process played an important role in the whole recycle combination process as it could improve the biodegradability of the high concentration starch wastewater. However, from the other experiments, the negative effect of hydrolytic acidification was found in the hydrolytic-aerobic combination, which suggested that the aerobic microorganisms needed time to adapt themselves to the acidic environment. The effect of the degrading time, which was spent in the hydrolytic and aerobic unit, and the number of circulations, with which the wastewater went through the two units were investigated. It was found that a recycle combination of 6 h hydrolytic process with 12 h aerobic process was highly effective and potentially economical, in which the final removal efficiency of CODcr and efficiency of starch degradation reached 94.1% and 98.8%, respectively.

  3. Recycling cellulases for cellulosic ethanol production at industrial relevant conditions: potential and temperature dependency at high solid processes.

    Science.gov (United States)

    Lindedam, Jane; Haven, Mai Østergaard; Chylenski, Piotr; Jørgensen, Henning; Felby, Claus

    2013-11-01

    Different versions of two commercial cellulases were tested for their recyclability of enzymatic activity at high dry matter processes (12% or 25% DM). Recyclability was assessed by measuring remaining enzyme activity in fermentation broth and the ability of enzymes to hydrolyse fresh, pretreated wheat straw. Industrial conditions were used to study the impact of hydrolysis temperature (40 or 50°C) and residence time on recyclability. Enzyme recycling at 12% DM indicated that hydrolysis at 50°C, though ideal for ethanol yield, should be kept short or carried out at lower temperature to preserve enzymatic activity. Best results for enzyme recycling at 25% DM was 59% and 41% of original enzyme load for a Celluclast:Novozyme188 mixture and a modern cellulase preparation, respectively. However, issues with stability of enzymes and their strong adsorption to residual solids still pose a challenge for applicable methods in enzyme recycling.

  4. Recycle for Sludge Scrap of Nd-Fe-B Sintered Magnet as Isotropic Bonded Magnet

    Institute of Scientific and Technical Information of China (English)

    Masahiro Itoh; Masahiro Masuda; Shunji Suzuki; Ken-ichi Machida

    2004-01-01

    The reduction diffusion method was performed for the sludge scrap of Nd-Fe-B sintered magnets with adding Ca metal to recover the oxidized Nd-Fe-B phase. After washing the resultant powders to remove Ca metal component, the powders obtained were recycled as an isotropic magnetic powder by the melt spinning method. The magnetic properties of powders as recycled were inferior, especially for the coercivity value, due to the deletion of rare earth metals during the washing process. The adjustment of metal composition, i.e., the addition of Nd metal, at the melt spinning process improved the magnetic properties to be Br=~0.75 T, Hcj=~0.93 mA·m-1, and(BH)max=~91 kJ·m-3. The magnetic properties of the bonded magnets prepared from the composition-adjusted powders were Br=~0.66 T, Hcj=~0.92 mA·m-1, and(BH)max=~70 kJ·m-3, which are approximately comparable to the commercially available MQPB boned one(Br=~0.73 T, Hcj=~0.79 mA·m-1, and(BH)max=~86 kJ·m-3).

  5. Fractionation and fluxes of metals and radionuclides during the recycling process of phosphogypsum wastes applied to mineral CO₂ sequestration.

    Science.gov (United States)

    Contreras, M; Pérez-López, R; Gázquez, M J; Morales-Flórez, V; Santos, A; Esquivias, L; Bolívar, J P

    2015-11-01

    The industry of phosphoric acid produces a calcium-rich by-product known as phosphogypsum, which is usually stored in large stacks of millions of tons. Up to now, no commercial application has been widely implemented for its reuse because of the significant presence of potentially toxic contaminants. This work confirmed that up to 96% of the calcium of phosphogypsum could be recycled for CO2 mineral sequestration by a simple two-step process: alkaline dissolution and aqueous carbonation, under ambient pressure and temperature. This CO2 sequestration process based on recycling phosphogypsum wastes would help to mitigate greenhouse gasses emissions. Yet this work goes beyond the validation of the sequestration procedure; it tracks the contaminants, such as trace metals or radionuclides, during the recycling process in the phosphogypsum. Thus, most of the contaminants were transferred from raw phosphogypsum to portlandite, obtained by dissolution of the phosphogypsum in soda, and from portlandite to calcite during aqueous carbonation. These findings provide valuable information for managing phosphogypsum wastes and designing potential technological applications of the by-products of this environmentally-friendly proposal.

  6. New insights into polyurethane biodegradation and realistic prospects for the development of a sustainable waste recycling process.

    Science.gov (United States)

    Cregut, Mickael; Bedas, M; Durand, M-J; Thouand, G

    2013-12-01

    Polyurethanes are polymeric plastics that were first used as substitutes for traditional polymers suspected to release volatile organic hazardous substances. The limitless conformations and formulations of polyurethanes enabled their use in a wide variety of applications. Because approximately 10 Mt of polyurethanes is produced each year, environmental concern over their considerable contribution to landfill waste accumulation appeared in the 1990s. To date, no recycling processes allow for the efficient reuse of polyurethane waste due to their high resistance to (a)biotic disturbances. To find alternatives to systematic accumulation or incineration of polyurethanes, a bibliographic analysis was performed on major scientific advances in the polyurethane (bio)degradation field to identify opportunities for the development of new technologies to recondition this material. Until polymers exhibiting oxo- or hydro-biodegradative traits are generated, conventional polyurethanes that are known to be only slightly biodegradable are of great concern. The research focused on polyurethane biodegradation highlights recent attempts to reprocess conventional industrial polyurethanes via microbial or enzymatic degradation. This review describes several wonderful opportunities for the establishment of new processes for polyurethane recycling. Meeting these new challenges could lead to the development of sustainable management processes involving polymer recycling or reuse as environmentally safe options for industries. The ability to upgrade polyurethane wastes to chemical compounds with a higher added value would be especially attractive.

  7. Formation of PBDD/F from PBDE in electronic waste in recycling processes and under simulated extruding conditions.

    Science.gov (United States)

    Zennegg, Markus; Schluep, Mathias; Streicher-Porte, Martin; Lienemann, Peter; Haag, Regula; Gerecke, Andreas C

    2014-12-01

    The increasing volumes of waste electrical and electronic equipment (WEEE) in Europe and developing economies demand for efficient disposal solutions. However, WEEE also contains toxic compounds and, therefore, there is a need for recycling technologies for WEEE that creates revenue without causing environmental harm. Among other fast developing economies, South Africa is tempting to make use of recycled plastic. Brominated flame retardants (BFRs) are additives used to protect plastic materials in electrical and electronic equipment (EEE) against ignition. Some BFRs are known persistent organic pollutants (POPs) and some BFRs can be transformed into highly toxic compounds such as polybrominated dibenzofurans and dioxins (PBDD/Fs). In this study, the contents of critical BFRs, i.e. polybrominated diphenyl ethers, and highly toxic PBDD/Fs were measured in WEEE material from Switzerland and South Africa. The formation of PBDD/Fs has been observed in two South African recycling processes and under controlled laboratory conditions. Total PBDE-contents in the South African and Swiss plastic waste varied between 1×10(3) and 7×10(6) μg kg(-1). A few WEEE plastic fractions exceeded the RoHS limit of 1×10(6) μg kg(-1) for PBDEs and thus they could not be used for recycling products without special treatment. The total content of ∑PBDFs was around 1×10(3) μg kg(-1). Such contents in materials do not pose a risk for consumer under normal conditions. Workers at recycling plants might be at risk. The measured formation rates of PBDFs were between 2×10(-5) and 2×10(-4)∑PBDE(-1) min(-1).

  8. DMS cyclone separation processes for optimization of plastic wastes recycling and their implications.

    Science.gov (United States)

    Gent, Malcolm Richard; Menendez, Mario; Toraño, Javier; Torno, Susana

    2011-06-01

    It is demonstrated that substantial reductions in plastics presently disposed of in landfills can be achieved by cyclone density media separation (DMS). In comparison with the size fraction of plastics presently processed by industrial density separations (generally 6.4 to 9.5 mm), cyclone DMS methods are demonstrated to effectively process a substantially greater range of particle sizes (from 0.5 up to 120 mm). The purities of plastic products and recoveries obtained with a single stage separation using a cylindrical cyclone are shown to attain virtually 100% purity and recoveries >99% for high-density fractions and >98% purity and recoveries were obtained for low-density products. Four alternative schemas of multi-stage separations are presented and analyzed as proposed methods to obtain total low- and high-density plastics fraction recoveries while maintaining near 100% purities. The results of preliminary tests of two of these show that the potential for processing product purities and recoveries >99.98% of both density fractions are indicated. A preliminary economic comparison of capital costs of DMS systems suggests cyclone DMS methods to be comparable with other DMS processes even if the high volume capacity for recycling operations of these is not optimized.

  9. Recycling of electric arc furnace (EAF dust for use in steel making process

    Directory of Open Access Journals (Sweden)

    José Alencastro de Araújo

    2014-07-01

    Full Text Available The EAF dust is listed as hazardous waste from specific source, K061, according to ABNT 10004:2004 and constitutes one of the major problems of electrical steel plant. This work suggests recycling of the EAF dust by sintering of a composite, pre-cast agglomerate (PCA consisting of EAF dust agglomerate to coke particles, mill scale and ceramic fluorite into pellets. The work was divided into three stages, in the first stage the technical viability of using only solid waste industrial to produce a PCA was observed, in the second phase, the main effects between the components of the PCA to obtain the optimal formulation was tested. In the third phase the intensity of the variables, coke and fluorite ceramics, for removing zinc of PCA was checked. Every stage was chemically analyzed by X-ray fluorescence spectrometer and X-ray diffraction. The first two stages of the production PCA were carried out in a pilot plant sintering downstream and the third phase in a pilot plant upstream. As a result of the process two by-products were obtained, the pre-cast agglomerated, PCA, with total iron content exceeding 70%, object of the process of sintering and zinc dust, containing more than 50% zinc resulting from volatilization of this metal during the sintering process and collected by bag filter. In addition, approximately 90% of lead and cadmium contained in the initial EAF dust was extracted.

  10. Kevlar based nanofibrous particles as robust, effective and recyclable absorbents for water purification.

    Science.gov (United States)

    Nie, Chuanxiong; Peng, Zihang; Yang, Ye; Cheng, Chong; Ma, Lang; Zhao, Changsheng

    2016-11-15

    Developing robust and recyclable absorbents for water purification is of great demand to control water pollution and to provide sustainable water resources. Herein, for the first time, we reported the fabrication of Kevlar nanofiber (KNF) based composite particles for water purification. Both the KNF and KNF-carbon nanotube composite particles can be produced in large-scale by automatic injection of casting solution into ethanol. The resulted nanofibrous particles showed high adsorption capacities towards various pollutants, including metal ions, phenylic compounds and various dyes. Meanwhile, the adsorption process towards dyes was found to fit well with the pseudo-second-order model, while the adsorption speed was controlled by intraparticle diffusion. Furthermore, the adsorption capacities of the nanofibrous particles could be easily recovered by washing with ethanol. In general, the KNF based particles integrate the advantages of easy production, robust and effective adsorption performances, as well as good recyclability, which can be used as robust absorbents to remove toxic molecules and forward the application of absorbents in water purification.

  11. Recycling Trends in the Plastics Manufacturing and Recycling Companies in Malaysia

    Science.gov (United States)

    Wahab, D. A.; Abidin, A.; Azhari, C. H.

    This study presents the findings from a study on the consumption of recycled materials and recycling practices in the plastics manufacturing industry and recycling companies in Malaysia. The findings were obtained from a survey conducted in twenty plastic manufacturing companies and detailed case studies in three recycling companies. The survey conducted in the plastic manufacturing companies` shows that the consumption rate for poly-olefins (PP and PE) is the highest among the resin types and the industrial sector that consumes the most plastic materials is the electrical and electronics sector. The consumption of recycled materials is high among the local manufacturing companies (80%) which are largely due to cost savings; about 20% of these companies conducted in-house recycling. The study has also shown that the medium scale industry consumes the most recycled materials as compared to the large and small scale industry. The rate of disposal for plastic materials in the local industry is approximately 5%. The detailed case studies conducted in the recycling companies have successfully identified the main processes involved in plastic recycling namely manual sorting, cleaning, drying, meshing/pelletising and packaging. These recycling companies obtained recycled materials from various sources including industrial scrap, dumping sites, local producers as well as imported sources. Pricing of recycled materials were based on classification according to grade and quality of the recycled materials. The study has reflected the extent of in-house recycling trends in the local plastic manufacturing companies and their dependency on the supply from the local recycling companies.

  12. Recycling of food waste as nutrients in Chlorella vulgaris cultivation.

    Science.gov (United States)

    Lau, Kin Yan; Pleissner, Daniel; Lin, Carol Sze Ki

    2014-10-01

    Heterotrophic cultivation of Chlorella vulgaris was investigated in food waste hydrolysate. The highest exponential growth rate in terms of biomass of 0.8day(-1) was obtained in a hydrolysate consisting of 17.9gL(-1) glucose, 0.1gL(-1) free amino nitrogen, 0.3gL(-1) phosphate and 4.8mgL(-1) nitrate, while the growth rate was reduced in higher concentrated hydrolysates. C. vulgaris utilized the nutrients recovered from food waste for the formation of biomass and 0.9g biomass was produced per gram glucose consumed. The microalgal biomass produced in nutrient sufficient batch cultures consisted of around 400mgg(-1) carbohydrates, 200mgg(-1) proteins and 200mgg(-1) lipids. The conversion of nutrients derived from food waste and the balanced biomass composition make C. vulgaris a promising strain for the recycling of food waste in food, feed and fuel productions.

  13. Capture of Tritium Released from Cladding in the Zirconium Recycle Process

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, Barry B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Walker, T. B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bruffey, S. H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); DelCul, Guillermo Daniel [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-08-31

    Zirconium may be recovered from the Zircaloy® cladding of used nuclear fuel (UNF) for recycle or to reduce the quantities of high-level waste destined for a geologic repository. Recovery of zirconium using a chlorination process is currently under development at the Oak Ridge National Laboratory. The approach is to treat the cladding with chlorine gas to convert the zirconium in the alloy (~98 wt % of the alloy mass) to zirconium tetrachloride. A significant fraction of the tritium (0–96%) produced in nuclear fuel during irradiation may be found in zirconium-based cladding and could be released from the cladding when the solid matrix is destroyed by the chlorination reaction. To prevent uncontrolled release of radioactive tritium to other parts of the plant or to the environment, a method to recover the tritium may be required. The focus of this effort was to (1) identify potential methods for the recovery of tritium from the off-gas of the zirconium recycle process, (2) perform scoping tests on selected recovery methods using nonradioactive gas simulants, and (3) select a process design appropriate for testing on radioactive gas streams generated by the engineering-scale zirconium recycle demonstrations on radioactive used cladding.

  14. Reduce, Reuse, Recycle: Planetary Nebulae as Green Galactic Citizens

    CERN Document Server

    Kwitter, K B

    2011-01-01

    We review gas-phase abundances in PNe and describe their dual utility as archives of original progenitor metallicity via the alpha elements, as well as sources of processed material from nucleosynthesis during the star's evolution, i.e., C, N, and s-process elements. We describe the analysis of PN spectra to derive abundances and discuss the discrepancies that arise from different choices at each step. Abundance results for the Milky Way and Magellanic Clouds from various groups of investigators are presented; the observational results are compared with theoretical predictions of AGB stellar yields. Finally, we suggest areas where more work is needed to improve our abilities to determine abundances in PNe.

  15. Recycling Jorf Lasfar fly ash as an additive to cement

    Directory of Open Access Journals (Sweden)

    Hamadi A

    2012-09-01

    Full Text Available Recycling fly ash is a good example of valorization of waste. It gives a solution the environmental problem by avoiding land filling, and reducing CO2 emission in the atmosphere. In this work we studied the physical-chemical characteristics of Jorf Lasfar fly ash. The parameters investigated were particle size, density, specific surface Blaine, chemical and mineralogical compositions. The techniques used are scanning electronic microscope (SEM, transmission electronic microscope (TEM, X-rays fluorescence (XRF, X-rays diffraction (XRD and atomic spectrometry emission coupled with inductive plasma ICP. We also conducted a study on the mechanical behavior of type CPJ45 cements produced from a combined grinding of clinker, limestone and gypsum. The substitution of a portion of the clinker by different percentages of fly ash was conducted. We noticed that the compression and bending resistances for these mixtures went through a maximum at 28 days with the addition of 7% (by mass of ash. This result showed that the mineral and chemical compositions of this ash conferred a Pozzoulanic power to the cement studied.

  16. "2sDR": Process Development of a Sustainable Way to Recycle Steel Mill Dusts in the 21st Century

    Science.gov (United States)

    Rösler, Gernot; Pichler, Christoph; Antrekowitsch, Jürgen; Wegscheider, Stefan

    2014-09-01

    Significant amounts of electric arc furnace dust originating from steel production are recycled every year by the Waelz process, despite the fact that this type of process has several disadvantages. One alternative method would be the recovery of very high-quality ZnO as well as iron and even chromium in the two-step dust recycling process, which was invented to treat special waste for the recovery of heavy metal-containing residues. The big advantage of that process is that various types of residues, especially dusts, can be treated in an oxidizing first step for cleaning, with a subsequent reducing step for the metal recovery. After the treatment, three different fractions—dust, slag, and an iron alloy, can be used without any limitations. This study focuses on the development of the process along with some thermodynamic considerations. Moreover, a final overview of mass balances of an experiment performed in a 100-kg top blowing rotary converter with further developments is provided.

  17. Boric acid as cost-effective and recyclable catalyst for trimethylsilyl protection and deprotection of alcohols and phenols

    Energy Technology Data Exchange (ETDEWEB)

    Rostami, Amin; Akradi, Jamal; Ahmad-Jangi, Firoz, E-mail: a_rostami372@yahoo.co [University of Kurdistan, Sanandaj (Iran, Islamic Republic of). Faculty of Science. Dept. of Chemistry

    2010-07-01

    Boric acid has been used as a green, selective and recyclable catalyst for trimethysilylation of alcohols and phenols using hexamethyldisilazane in acetonitrile. Deprotection of trimethylsilyl ethers to their parent alcohols and phenols was also achieved using this catalyst in water at room temperature. The salient features of this methodology are cheap processing, mild acidity conditions, excellent yields of products and easy availability of the catalyst. (author)

  18. Geological Disposal Options for the Radioactive Wastes from a Recycling Process of Spent Nuclear Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. Y.; Choi, H. J.; Lee, M. S.; Jeong, J. T.; Choi, J. W.; Kim, S. K.; Cho, D. K.; Kuk, D. H.; Cha, J. H

    2008-10-15

    The electricity from the nuclear power plants is around 40 % of total required electricity in Korea and according to the energy development plan, the proportion will be raised about 60 % in near future. To implement this plan, the most important factor is the back-end fuel cycle, namely the safe management of the spent fuel or high level radioactive wastes from the nuclear power plants. Various researches are being carried out to manage the spent fuel effectively in the world. In our country, as one of the management alternatives which is more effective and non-proliferation, pyro-processing method is being developed actively to retrieve reusable uranium and TRU, and to reduce the volume of high level waste from a Nuclear power plant. This is a new dry recycling process. In this report, the amount of various wastes and their characteristics are estimated in a Pyro-process. Based on these information, the geological disposal alternatives are developed. According to the amount and the characteristics of each waste, the concepts of waste packages and the disposal container are developed. And also from the characteristics of the radioactivity and the heat generation, multi-layer of the depth is considered to dispose these wastes. The proposed various alternatives in this report can be used as input data for design of the deep geological disposal system. And they will be improved through the application of the real site data and safety assessment in the future. After then, the final disposal concept will be selected with various assessment and the optimization will be carried out.

  19. Recycling as a strategy against rare earth element criticality: a systemic evaluation of the potential yield of NdFeB magnet recycling.

    Science.gov (United States)

    Rademaker, Jelle H; Kleijn, René; Yang, Yongxiang

    2013-09-17

    End-of-life recycling is promoted by OECD countries as a promising strategy in the current global supply crisis surrounding rare earth elements (REEs) so that dependence on China, the dominant supplier, can be decreased. So far the feasibility and potential yield of REE recycling has not been systematically evaluated. This paper estimates the annual waste flows of neodymium and dysprosium from permanent magnets, the main deployment of these critical REEs, during the 2011-2030 period. The estimates focus on three key permanent magnet waste flows: wind turbines, hybrid and electric vehicles, and hard disk drives (HDDs) in personal computers (PCs). This is a good indication of the end-of-life recycling of neodymium and dysprosium maximum potential yield. Results show that for some time to come, waste flows from permanent magnets will remain small relative to the rapidly growing global REE demand. Policymakers therefore need to be aware that during the next decade recycling is unlikely to substantially contribute to global REE supply security. In the long term, waste flows will increase sharply and will meet a substantial part of the total demand for these metals. Future REE recycling efforts should, therefore, focus on the development of recycling technology and infrastructure.

  20. Mathematical modeling of a continuous alcoholic fermentation process in a two-stage tower reactor cascade with flocculating yeast recycle.

    Science.gov (United States)

    de Oliveira, Samuel Conceição; de Castro, Heizir Ferreira; Visconti, Alexandre Eliseu Stourdze; Giudici, Reinaldo

    2015-03-01

    Experiments of continuous alcoholic fermentation of sugarcane juice with flocculating yeast recycle were conducted in a system of two 0.22-L tower bioreactors in series, operated at a range of dilution rates (D 1 = D 2 = 0.27-0.95 h(-1)), constant recycle ratio (α = F R /F = 4.0) and a sugar concentration in the feed stream (S 0) around 150 g/L. The data obtained in these experimental conditions were used to adjust the parameters of a mathematical model previously developed for the single-stage process. This model considers each of the tower bioreactors as a perfectly mixed continuous reactor and the kinetics of cell growth and product formation takes into account the limitation by substrate and the inhibition by ethanol and biomass, as well as the substrate consumption for cellular maintenance. The model predictions agreed satisfactorily with the measurements taken in both stages of the cascade. The major differences with respect to the kinetic parameters previously estimated for a single-stage system were observed for the maximum specific growth rate, for the inhibition constants of cell growth and for the specific rate of substrate consumption for cell maintenance. Mathematical models were validated and used to simulate alternative operating conditions as well as to analyze the performance of the two-stage process against that of the single-stage process.

  1. The thermal transformation of Man Made Vitreous Fibers (MMVF) and safe recycling as secondary raw materials (SRM).

    Science.gov (United States)

    Gualtieri, A F; Foresti, E; Lesci, I G; Roveri, N; Gualtieri, M Lassinantti; Dondi, M; Zapparoli, M

    2009-03-15

    This work describes the high temperature reaction sequence of commercial Man Made Vitreous Fibers (MMVF) Cerafiber, Superwool, Rock wool and Glass wool which may be used as substitute for asbestos in some industrial applications. Knowledge of the reaction path and transformation sequence is very important to assess whether carcinogenic crystalline phases are formed during devitrification, which may occur when used as insulators. In addition, knowledge about the nature of the phases formed at high temperature is mandatory to assess if thermally transformed MMVF can be safely recycled as secondary raw material (SRM). In this scenario, this study provides useful information for the optimization of the industrial annealing process aimed to attain a safe, recyclable product. The results of this work show that one of the high-temperature products of Cerafiber and Superwool is cristobalite which is classified as a carcinogenic. It was possible to define the temperature interval at which Cerafiber and Superwool fibers can be safely used as thermal insulators (e.g. insulators in tunnel and/or roller kilns, etc.). As cristobalite is formed in both synthetic fiber products at temperatures higher than 1200 degrees C, their use should be limited to devices operating at lower temperatures. Rock and Glass wool melt upon thermal treatment. As far as the industrial process of inertization is concerned, a maximum firing temperature of 1100 and 600 degrees C is required to melt Rock wool and Glass wool, respectively, with the high-temperature products that can be safely recycled as SRM. Recycling of these products in stoneware tile mixtures were subsequently attempted. The addition of 1-2 wt.% of the melts of Rock and Glass wool gave promising results in terms of viscous sintering reactions and resistance to staining with the only weak characteristic being the color properties of the fired bodies which tend to worsen.

  2. Process for recycling components of a PEM fuel cell membrane electrode assembly

    Science.gov (United States)

    Shore, Lawrence [Edison, NJ

    2012-02-28

    The membrane electrode assembly (MEA) of a PEM fuel cell can be recycled by contacting the MEA with a lower alkyl alcohol solvent which separates the membrane from the anode and cathode layers of the assembly. The resulting solution containing both the polymer membrane and supported noble metal catalysts can be heated under mild conditions to disperse the polymer membrane as particles and the supported noble metal catalysts and polymer membrane particles separated by known filtration means.

  3. Treatment of wastewater from a low-temperature carbonization process industry through biological and chemical oxidation processes for recycle/reuse: a case study.

    Science.gov (United States)

    Biswas, R; Bagchi, S; Urewar, C; Gupta, D; Nandy, T

    2010-01-01

    Low-temperature carbonization (LTC) of coal generates highly complex wastewater warranting stringent treatment. Developing a techno-economically viable treatment facility for such wastewaters is a challenging task. The paper discusses a case study pertaining to an existing non-performing effluent treatment plant (ETP). The existing ETP comprising an ammonia stripper followed by a single stage biological oxidation was unable to treat 1,050 m(3)/d of effluent as per the stipulated discharge norms. The treated effluent from the existing ETP was characterized with high concentrations of ammonia (75-345 mg N/l), COD (313-1,422 mg/l) and cyanide (0.5-4 mg/l). Studies were undertaken to facilitate recycling/reuse of the treated effluent within the plant. A second stage biooxidation process was investigated at pilot scale for the treatment of the effluent from the ETP. This was further subjected to tertiary treatment with 0.5% dose of 4% hypochlorite which resulted in effluent with pH: 6.6-6.8, COD: 73-121 mg/l, and BOD(5):recycle and reuse. Thus, a modified treatment scheme comprising ammonia pre-stripping followed by two-stage biooxidation process and a chemical oxidation step with hypochlorite at tertiary stage was proposed for recycle/reuse of LTC wastewater.

  4. Utilization of cement treated recycled concrete aggregates as base or subbase layer in Egypt

    Directory of Open Access Journals (Sweden)

    Ahmed Ebrahim Abu El-Maaty Behiry

    2013-12-01

    Full Text Available Recently, environmental protection has a great concern in Egypt where recycling of increased demolition debris has become a viable option to be incorporated into roads applications. An extensive laboratory program is conducted to study the feasibility of using recycled concrete aggregate (RCA mixed with traditional limestone aggregate (LSA which is currently being used in base or subbase applications in Egypt. Moreover, the influence of mixture variables on the mechanical properties of cement treated recycled aggregate (CTRA is investigated. Models to predict the compressive and tensile strengths based on mixture parameters are established. The results show that the adding of RCA improves the mechanical properties of the mixture where the unconfined compressive strength (UCS is taken as an important quality indicator. Variables influencing the UCS such as cement content, curing time, dry density play important roles to determine the performance of CTRA.

  5. Electrolytic arsenic removal for recycling of washing solutions in a remediation process of CCA-treated wood.

    Science.gov (United States)

    Nanseu-Njiki, Charles-Péguy; Alonzo, Véronique; Bartak, Duane; Ngameni, Emmanuel; Darchen, André

    2007-10-01

    The remediation of chromated copper arsenate or CCA-treated wood is a challenging problem in many countries. In a wet remediation, the recycling of the washing solutions is the key step for a successful process. Within this goal, owing to its solubility and its toxicity, the removal of arsenic from washing solution is the most difficult process. The efficiency of arsenic removal from As(III) solutions by electrolysis was investigated in view of the recycling of acidic washing solutions usable in the remediation of CCA-treated wood. Electrochemical reduction of As(III) is irreversible and thus difficult to perform at carbon electrodes. However the electrolytic extraction of arsenic can be performed by the concomitant reduction of the cupric cation and arsenite anion. The cathodic deposits obtained by controlled potential electrolysis were analyzed by X-ray diffraction (XRD) and energy dispersive X-ray microanalysis. XRD diffraction data indicated that these deposits were mixtures of copper and copper arsenides Cu(3)As and Cu(5)As(2). Electrolysis was carried out in an undivided cell with graphite cathode and copper anode, under a controlled nitrogen atmosphere. The evolution of arsine gas AsH(3) was not observed under these conditions.

  6. Scientific Opinion on the safety evaluation of the process “Holfeld Diamat” used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2013-03-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the recycling process Holfeld Diamat (EC register number RECYC076 which is based on the Diamat ® technology. The input of the process is washed and dried PET flakes originating from collected post-consumer PET containers, mainly bottles, containing no more than 5 % of PET from non-food consumer applications. Through this process, post-consumer washed and dried PET flakes are mixed up to 50 % with virgin PET flakes before being heated in a crystallisation reactor (step 2 and extruded under vacuum into sheets (step 3. After having examined the challenge tests provided, the Panel concluded that the decontamination in the two consecutive extruders step 3 is the critical step for the decontamination efficiency of the process. The operating parameters to control its performance are well defined and are the temperature, the pressure and the residence time. The operating parameters of these steps in the process are at least as severe as those obtained from the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.15 μg/kg food derived from the exposure scenario for toddlers. Therefore, the recycled PET obtained from the process Holfeld Diamat intended for the manufacture of recycled thermoformed trays and containers made with up to 50 % recycled post-consumer PET and intended for contact for long term storage at room temperature with all types of foodstuffs except packaged water is not considered of safety concern.

  7. Scientific Opinion on the safety assessment of the process “RPC Cobelplast” used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2014-05-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the recycling process RPC Cobelplast (EU register No RECYC099 which is based on the Bandera® technology. The input of the process is washed and dried PET flakes originating from collected post-consumer PET containers, mainly bottles, containing no more than 5 % of PET from non-food consumer applications. Through this process, post-consumer washed and dried PET flakes are mixed with typically 50 % virgin PET flakes before being extruded under vacuum into sheets. Having examined the challenge tests provided, the Panel concluded that the decontamination in the extruder under vacuum degassing is the critical step for the decontamination efficiency of the process. The operating parameters to control its performance are well defined and are temperature, pressure and residence time. The operating parameters of this step in the process are at least as severe as those obtained from the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore, the recycled PET obtained from the process RPC Cobelplast intended for the manufacture of recycled thermoformed trays and containers made with up to 100 % recycled post-consumer PET and intended for contact for long term storage at room temperature with all types of foodstuffs is not considered of safety concern.

  8. Potential of a Hydrometallurgical Recycling Process for Catalysts to Cover the Demand for Critical Metals, Like PGMs and Cerium

    Science.gov (United States)

    Steinlechner, Stefan; Antrekowitsch, Jürgen

    2015-02-01

    The metals from the platinum group are used in many different industries, for example dental, jewelry, and chemicals. Nevertheless, the most important use is based on their catalytic properties. Approximately 50% of platinum and palladium are used as automotive and industrial catalysts. In case of rhodium, an even higher percentage (around 80-90%) is used as an alloying element in the active layer of different catalysts. The high required amount of 300-900 kg of treated ore to obtain approximately 1 g of PGM is responsible for the high prices. On average, the contents in the ore of Pt and Pd are 5-10 times higher than Rh and Ru and around 50 times higher than Ir and Os. Additionally, the regional limitation of ore bodies leads to a strong dependence on mainly South Africa and Russia as PGM suppliers. Based on the strong discrepancy in supply and demand of PGM's around the world, recycling of catalysts is mandatory and meaningful from the ecological and economical point of view. Based on the high prices of PGM, the industry is forced to improve the efficiency of catalysts, which is done by improving the wash coat technology. By using rare-earth elements, like cerium oxide, the surface can be increased and the ability to supply oxygen is secured. As a side effect, cerium as an additional critical element is introduced into the recycling circuit of catalytic converters, forming a further valuable component and forming a major challenge for common pyrometallurgical converter recycling. Therefore, this article introduces a hydrometallurgical process, developed together with Railly&Hill Inc., for PGM as well as cerium recovery from catalytic converters.

  9. Recycling of quarry waste as part of sustainable aggregate production: Norwegian and Italian point of view

    Science.gov (United States)

    Antonella Dino, Giovanna; Willy Danielsen, Svein; Chiappino, Claudia; Primavori, Piero; Engelsen, Christian John

    2016-04-01

    Resource preservation is one of the main challenges in Europe, together with waste management and recycling; recently several researchers are interested in the recovering of critical raw materials and secondary raw materials from landfill. Aggregate supply, even if it is not "critical" sensus stricto (s.s.), is one of the European priorities (low value but high volume needs). On the other side, the management of quarry waste , mainly from dimension stones, but also as fines from aggregate crushing, is still a matter of concern. Such materials are managed in different ways both locally and nationwide, and often they are landfilled, because of an unclear legislation and a general lack of data. Most of time the local authorities adopt the maximum precaution principle or the enterprises find it little profitable to recover them, so that the sustainable recycling of such material is not valued. Several studies have shown, depending on the material specific characteristics, the viability of recycling quarry waste into new raw materials used in glass and ceramic industries, precast concrete production, infrastructures etc. (Loudes et al. 2012, Dino&Marian 2015, Bozzola et al 2012, Dino et al. 2012, etc.). Thus, aggregate production may be one of the profitable ways to use quarry waste and is falling under the priority of EU (aggregate supply). Positive economic and environmental effects are likely to be achieved by systematic recycling of quarry waste planned by industries (industrial planning) and public authorities (national and local planning of aggregate exploitation). Today, the recycling level varies to a great extent and systematic recovery is not common among European Countries. In Italy and Norway no significant incentives on recycling or systematic approaches for local aggregate exploitation exist. The environmental consequences can be overexploitation of the natural resources, land take for the landfills, environmental contamination and landscape alteration by

  10. CHARACTERIZATION OF THE DUST GENERATED IN THE RECYCLING PROCESS OF THE ELECTRIC ARC FURNACE DUST

    Directory of Open Access Journals (Sweden)

    Fábio Gonçalves Rizz

    2013-10-01

    Full Text Available Electric Arc Furnace Dust (EAFD is a solid waste generated by the production of steel through the Electric Arc Furnace. This waste is labeled dangerous, which motivates studies aiming its recycling. Experiments were made to study a pyrometallurgical process for the recycling of the dust, using the insertion of dust briquettes in molten pig iron in three temperatures. In the briquettes, there were made additions of calcium fluoride in four different concentrations. This paper has the objective to characterize the dust that results from this process, verifying the influence of the temperature and the concentration of calcium fluoride in the briquette in the morphology and chemical composition of the new dust, determining the optimal conditions for the recovery of the zinc content of the dust. This newly generated dust was analyzed in an Scanning Electronic Microscope, used to capture micrographs and chemical composition by EDS. The micrographs show that the temperature and the calcium fluoride concentration interfere in the way the dust particles agglomerate. Chemical analysis points that the higher zinc recuperation occurrs in the experiments at 1500°C with 7% addition of calcium fluoride.

  11. Use of recycling through medium size granular filters to treat small food processing industry effluents.

    Science.gov (United States)

    Ménoret, C; Boutin, C; Liénard, A; Brissaud, F

    2002-01-01

    Currently there are no suitable wastewater treatment systems for effluents from small food processing industries (dairy, cheese, wine production). Such raw sewages are characterized by high organic matter concentrations (about 10 g COD L-1) and relatively low daily volumes (about 2 m3). An adaptation of attached-growth cultures on fine media processes, known to be easy and inexpensive to use, could fit both the technical and economical context of those industries. Coarser filter particle size distributions than those normally used allow a better aeration and reduce clogging risk. The transit time of the effluent through the porous filter materials is shortened and requires recycling to increase the contact time between the biomass and the substrate. A pilot plant was built to compare the efficiency of two kinds of filter materials, gravel (2-5 mm) and pozzolana (3-7 mm). Two measurement campaigns were undertaken on a full-scale unit dealing with cheese dairy effluents. Both pilot-scale and full-scale plants show high COD removal rates (> 95%). Pilot-scale experiments show that accumulation of organic matter leads to the clogging of the recycling filter. To prevent early clogging, a better definition of feeding cycles is needed.

  12. Recycle of electrolytically dissolved struvite as an alternative to enhance phosphate and nitrogen recovery from swine wastewater.

    Science.gov (United States)

    Liu, YingHao; Kumar, Sanjay; Kwag, JungHoon; Kim, JaeHwan; Kim, JeongDae; Ra, ChangSix

    2011-11-15

    Operational parameters such as electric voltage, NaCl, reaction time (RT) and initial struvite amount were optimized for struvite dissolution with a designed electrolysis reactor, and the effect of recycling the dissolved solution on the performance of struvite crystallization was also assessed. The electrolytic reactor was made of plexiglas having titanium plate coated with iridium oxide as anode (surface area: 400 cm(2)) and stainless steel plates as cathodes. For reutilization of dissolved struvite, four runs were conducted with different recycle ratio of the solution. Optimum conditions for the electric voltage, NaCl, RT and initial struvite amount were 7 V, 0.06%, 1.5h and 1.25 g/L, respectively. At the above optimized conditions, 49.17 mg/L phosphate (PO(4)(3-)-P) was dissolved and ammonium-nitrogen (NH(4)-N) got completely removed from the solution. When 0.0, 0.5, 1.0 and 2.0 moles of the dissolved struvite with respect to PO(4)(3-)-P in swine wastewater were recycled along with 0.5M magnesium chloride (MgCl(2)), the PO(4)(3-)-P removal was 63, 69, 71 and 79%, and NH(4)-N was 9, 31, 40 and 53%, respectively. Hence, the performance of struvite formation process was proportionally increased. It is concluded that struvite can be re-dissolved by electrolysis and reused as a source of P and Mg.

  13. Immobilization of BiOX (X = Cl, Br) on activated carbon fibers as recycled photocatalysts.

    Science.gov (United States)

    Jiang, Zaiyong; Huang, Baibiao; Lou, Zaizhu; Wang, Zeyan; Meng, Xiaodong; Liu, Yuanyuan; Qin, Xiaoyan; Zhang, Xiaoyang; Dai, Ying

    2014-06-14

    BiOX have been grown on the surface of activated carbon fibers (ACF) as recycled photocatalysts. The analysis results illustrate that electrostatic adsorption plays an important role in the formation of BiOX/ACF composites. The photocatalytic experimental results indicate that BiOX/ACF show excellent cyclic properties and stable performance.

  14. Waste Treatment Technology Process Development Plan For Hanford Waste Treatment Plant Low Activity Waste Recycle

    Energy Technology Data Exchange (ETDEWEB)

    McCabe, Daniel J.; Wilmarth, William R.; Nash, Charles A.

    2013-08-29

    The purpose of this Process Development Plan is to summarize the objectives and plans for the technology development activities for an alternative path for disposition of the recycle stream that will be generated in the Hanford Waste Treatment Plant Low Activity Waste (LAW) vitrification facility (LAW Recycle). This plan covers the first phase of the development activities. The baseline plan for disposition of this stream is to recycle it to the WTP Pretreatment Facility, where it will be concentrated by evaporation and returned to the LAW vitrification facility. Because this stream contains components that are volatile at melter temperatures and are also problematic for the glass waste form, they accumulate in the Recycle stream, exacerbating their impact on the number of LAW glass containers. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to acceptable concentrations in the LAW glass, and reducing the halides in the Recycle is a key component of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, this stream does not have a proven disposition path, and resolving this gap becomes vitally important. This task seeks to examine the impact of potential future disposition of this stream in the Hanford tank farms, and to develop a process that will remove radionuclides from this stream and allow its diversion to another disposition path, greatly decreasing the LAW vitrification mission duration and quantity of glass waste. The origin of this LAW Recycle stream will be from the Submerged Bed Scrubber (SBS) and the Wet Electrostatic Precipitator (WESP) from the LAW melter off-gas system. The stream is expected to be a dilute salt solution with near neutral pH, and will likely contain some insoluble solids from melter carryover or precipitates of scrubbed components (e.g. carbonates). The soluble

  15. Application of the analytic hierarchy process to the analysis of wastewater nutrient recycling options: a case based on a group study of residents in the city of Zurich.

    Science.gov (United States)

    Contreras, Francisco; Hanaki, Keisuke; Aramaki, Toshiya; Binder, Claudia R

    2013-01-01

    The recycling of anthropogenic nutrients derived from the wastewater management systems is often characterized by a complex and uncertain scenario, due not only to the nature of the process but also to the involvement of different stakeholder groups. Over the past 10 years in Switzerland, policies regarding the use of sewage sludge as fertilizer have gradually shifted to a ban on use in agriculture. As a result, alternative methods for the recycling of anthropogenic nutrients may play a relevant role in the near future. This paper uses the analytic hierarchy process (AHP) to examine more closely the nutrient-recycling dilemma by analysing the preferences of a group of German-speaking residents in the city of Zurich for various management scenarios. Nutrient recycling by the use of urine separation toilets and the BioCon treatment process are presented as possible management alternatives in addition to current practice. The study shows that AHP can incorporate the respondents' preferences and multiple objectives when evaluating alternatives with different attributes.

  16. Exploration of polyelectrolytes as draw solutes in forward osmosis processes

    KAUST Repository

    Ge, Qingchun

    2012-03-01

    The development of the forward osmosis (FO) process has been constrained by the slow development of appropriate draw solutions. Two significant concerns related to draw solutions are the draw solute leakage and intensiveenergy requirement in recycling draw solutes after the FO process. FO would be much attractive if there is no draw solute leakage and the recycle of draw solutes is easy and economic. In this study, polyelectrolytes of a series of polyacrylic acid sodium salts (PAA-Na), were explored as draw solutes in the FO process. The characteristics of high solubility in water and flexibility in structural configuration ensure the suitability of PAA-Na as draw solutes and their relative ease in recycle through pressure-driven membrane processes. The high water flux with insignificant salt leakage in the FO process and the high salt rejection in recycle processes reveal the superiority of PAA-Na to conventional ionic salts, such as NaCl, when comparing their FO performance via the same membranes. The repeatable performance of PAA-Na after recycle indicates the absence of any aggregation problems. The overall performance demonstrates that polyelectrolytes of PAA-Na series are promising as draw solutes, and the new concept of using polyelectrolytes as draw solutes in FO processes is applicable. © 2011 Elsevier Ltd.

  17. Comparison between existing recycle processes for composite materials - a study regarding microwave pyrolysis; Jaemfoerelse av befintliga aatervinningsprocesser foer kompositmaterial - en foerstudie gaellande mikrovaagspyrolys

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, Carina; Andreasson, Sune (Stena Metall AB (Sweden)); Skrifvars, Mikael; Aakesson, Dan (Hoegskolan i Boraas (Sweden))

    2009-07-01

    The purpose of this project has been to investigate the possibilities to use recycled composites as energy recycling based on microwave pyrolysis and also to evaluate the microwave pyrolysis technique for the recycling of combined materials, such as composites. Composites can be recycled by mechanically grinding into a material which can be used as a filler in virgin composites. However, several earlier studies have showed that this will give a material with inferior quality, and there is presently no economical viable use of the recycled material. Composites can be incinerated together with other waste materials but the high content of inorganic material results in a material with low energy content. Composites typically contain 40-50 weight-% glass fibres, and in some cases be as high as 60-75 weight-%. Consequently, composites often end up at landfill sites and processes to recycle composites do not exit. Large volumes of composites are produced in Europe and these products will largely end up on landfill site after end-of-life as systems to recycle these products do not exist. These composites represent a large amount of energy which presently is not utilized. Processes and materials to produce composites are being developed continuously. This in addition to the need for light weight materials in the aerospace, windmills and automotive industry spurs the use of composites. It is therefore of outmost importance to develop processes to recycle of composites. Recycling of composites by the use of microwave pyrolysis has been studied in this project. Microwave pyrolysis is a process where the material is heated by microwave in an inert environment. The project has been focusing on the recycling of glass fibre reinforced composites as this type of composite makes the large volume of composites. Pyrolysis of glass fibre reinforce composites will result in two fractions - one oil fraction and one inorganic fraction. The oil fraction was analyzed with calorimetry and

  18. Recycling Facilities - Land Recycling Cleanup Locations

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Land Recycling Cleanup Location Land Recycling Cleanup Locations (LRCL) are divided into one or more sub-facilities categorized as media: Air, Contained Release or...

  19. Effects of ultrasound pretreatment on the characteristic evolutions of drinking water treatment sludge and its impact on coagulation property of sludge recycling process.

    Science.gov (United States)

    Zhou, Zhiwei; Yang, Yanling; Li, Xing

    2015-11-01

    Large amounts of drinking water treatment sludge (DWTS) are produced during the flocculation or flotation process. The recycling of DWTS is important for reducing and reclaiming the waste residues from drinking water treatment. To improve the coagulation step of the DWTS recycling process, power ultrasound was used as a pretreatment to disintegrate the DWTS and degrade or inactivate the constituents that are difficult to remove by coagulation. The effects of ultrasound pretreatment on the characteristics of DWTS, including the extent of disintegration, variation in DWTS floc characteristics, and DWTS dewaterability, were investigated. The capacity of the recycling process to remove particulates and organic matter from low-turbidity surface water compared to a control treatment process without DWTS was subsequently evaluated. The coagulation mechanism was further investigated by analyzing the formation, breakage, and re-growth of re-coagulated flocs. Our results indicated that under the low energy density applied (0.03-0.033 W/mL) for less than 15 min at a frequency of 160 kHz, the level of organic solubilization was less elevated, which was evidenced by the lower release of proteins and polysaccharides and lower fluorescence intensities of humic- and protein-like substances. The applied ultrasound conditions had an adverse effect on the dewaterability of the DWTS. Ultrasound pretreatment had no significant impact on the pH or surface charge of the DWTS flocs, whereas particle size decreased slightly and the specific surface area was moderately increased. The pollution removal capacity decreased somewhat for the recycled sonicated DWTS treatment, which was primarily ascribed to organic solubilization rather than variability in the floc characteristics of sonicated DWTS. The main coagulation mechanism was floc sweeping and physical adsorption. The breakage process of the flocs formed by the recycling process displayed distinct irreversibility, and the flocs were

  20. Study of the solubility and stability of polystyrene wastes in a dissolution recycling process.

    Science.gov (United States)

    García, María Teresa; Gracia, Ignacio; Duque, Gema; Lucas, Antonio de; Rodríguez, Juan Francisco

    2009-06-01

    Dissolution with suitable solvents is one of the cheapest and more efficient processes for polystyrene waste management. In this work the solubility of polystyrene foams in several solvents benzene, toluene, xylene, tetrahydrofuran, chloroform, 1,3-butanediol, 2-butanol, linalool, geraniol, d-limonene, p-cymene, terpinene, phellandrene, terpineol, menthol, eucalyptol, cinnamaldheyde, nitrobenzene, N,N-dimethylformamide and water has been determined. Experimental results have shown that to develop a "green process" the constituents of essential oils, d-limonene, p-cymene, terpinene, phellandrene, are the most appropriate solvents. The action of these solvent does not produce any degradation of polymer chains. The solubility of the polymer in the mentioned solvents at different temperatures has been investigated. The solvent can be easily recycled by distillation.

  1. An assessment on the recycling opportunities of wastes emanating from scrap metal processing in Mauritius.

    Science.gov (United States)

    Mauthoor, Sumayya; Mohee, Romeela; Kowlesser, Prakash

    2014-10-01

    This paper presents an assessment on the wastes namely slag, dust, mill scale and sludge resulting from scrap metal processing. The aim of this study is to demonstrate that there are various ways via which scrap metal processing wastes can be reused or recycled in other applications instead of simply diverting them to the landfill. These wastes are briefly described and an overview on the different areas of applications is presented. Based on the results obtained, the waste generation factor developed was 349.3 kg per ton of steel produced and it was reported that slag represents 72% of the total wastes emanating from the iron and steel industry in Mauritius. Finally the suitability of the different treatment and valorisation options in the context of Mauritius is examined.

  2. ON THE BLACK LIQUOR AND RECYCLE COOKING OF AS-AQ STRAW PULP

    Institute of Scientific and Technical Information of China (English)

    HaiqiangShi; BeihaiHe; BingyueLiu

    2004-01-01

    Thick black liquor, thin black liquor and solid state sodium hydroxide are added to the liquor treated by sulfur dioxide, then the blended liquor is used to recycle cooking of straw pulp. The black liquor, separated liquor and pulp of every cycles are analyzed respectively. Result shows that the content of lignin and organism in recycle black liquor and separated liquor increases faster in the first three cycles and then continues to increase slowly till four or five times, after that it trends to a stable state. The main organism separated fi'om waste liquor of AS-AQ treated by sulfur dioxide is alkali-lignin,above 50% of total lignin in black liquor. The yield of pulp made fi'om recycle cooking is steady, the hardness of pulp has a great improvement with recycle cooking. The brightness of pulp reduces correspondingly before bleaching, and after bleaching the brightness of pulp is relatively high and steady at the same sodium hypo chlorite dosage.

  3. Compressive and Tensile Capacity of Recycled Aggregate Concrete (RAC with Glass as Supplement Material

    Directory of Open Access Journals (Sweden)

    Suraya Hani Adnan

    2013-12-01

    Full Text Available The amount of construction waste is increased significantly over the years due to reconstruction and the demolition of old buildings. One of the major challenges of our present society is to protect the environment by recycling the existing construction waste. This study concerned on two types of variable in the production of concrete which are the utilization of coarse recycled aggregate and utilization of different supplement ratio of fine glass wastes to cement. To evaluate the viability of this study, an experimental work was performed in order to monitor the mechanical behavior of such concrete. The compression and splitting tensile strength of concrete were determined on this study. From the result, it is conclude that the utilization of recycled aggregate does not much affect in the uniaxial compressive strength and splitting tensile strength of concrete, for replacement ratio up to 25 %. However, the utilization of fine glass as supplement material to cement is increase the uniaxial compressive and splitting tensile strength of concrete, for supplement ratio up to 5 %. Thus, it can be stated that the optimum concrete mixture is the mixture of 25 % recycled aggregate and 5% glass.

  4. Solid earth as a recycling systems and the lateral growth of Precambrian North America

    Science.gov (United States)

    Veizer, Jan

    1988-01-01

    If plotted on mass vs time diagrams, geologic entities (for example, continental and oceanic crust, sediments, and mineral resources) display an exponential (power law) relationship, with entity per unit time increasing toward the present. This relationship is consistent with the concept of recycling and can be simulated mathematically. The approach is based on the plate tectonic theory and considers area-age or mass-age distributions of crystalline basement and sediments for major global tectonic realms. Each tectonic realm is characterized by a specific lifespan, which is an inverse function of its recycling rate. The estimated average half-area of half-mass ages are given. The corresponding parameters for continental crust are 690 Ma for K/Ar, and approximately 1200 Ma for Rb/St and U-Th/Pb dating pairs. Tectonic diversity preserved in the geologic record is therefore a function of time, with oceanic tectonic realms, because of their rapid recycling, underrepresented in the rocks older than approximately 300 Ma. The Sm/Nd isotopic systematic of sediments suggest that, for a near steady-state post-Archean sedimentary mass, recycling is approximately 90 + or - 5 percent cannibalistic. This yields an estimated upper limit on crust-mantle exchange via sediment subduction of approximately 1.1 + or - 0.5 x 10 g a(sup -1) considerably less than demanded by isotopic constraints. The discrepancy may indicate the existence of additional loci, such as orogenic belts, for significant crust-mantle interaction.

  5. Coal liquefaction with preasphaltene recycle

    Science.gov (United States)

    Weimer, Robert F.; Miller, Robert N.

    1986-01-01

    A coal liquefaction system is disclosed with a novel preasphaltene recycle from a supercritical extraction unit to the slurry mix tank wherein the recycle stream contains at least 90% preasphaltenes (benzene insoluble, pyridine soluble organics) with other residual materials such as unconverted coal and ash. This subject process results in the production of asphaltene materials which can be subjected to hydrotreating to acquire a substitute for No. 6 fuel oil. The preasphaltene-predominant recycle reduces the hydrogen consumption for a process where asphaltene material is being sought.

  6. Recycling of PET bottles as fine aggregate in concrete.

    Science.gov (United States)

    Frigione, Mariaenrica

    2010-06-01

    An attempt to substitute in concrete the 5% by weight of fine aggregate (natural sand) with an equal weight of PET aggregates manufactured from the waste un-washed PET bottles (WPET), is presented. The WPET particles possessed a granulometry similar to that of the substituted sand. Specimens with different cement content and water/cement ratio were manufactured. Rheological characterization on fresh concrete and mechanical tests at the ages of 28 and 365days were performed on the WPET/concretes as well as on reference concretes containing only natural fine aggregate in order to investigate the influence of the substitution of WPET to the fine aggregate in concrete. It was found that the WPET concretes display similar workability characteristics, compressive strength and splitting tensile strength slightly lower that the reference concrete and a moderately higher ductility.

  7. Recycled fishing nets as reinforcement of existing concrete structures

    DEFF Research Database (Denmark)

    Sigvardsen, Nina Marie; Bonnerup, Amanda Helena; Ottosen, Lisbeth M.

    2016-01-01

    Large amounts of fishing nets are discarded every year polluting the oceans with plastic fibers on a global scale. Due to the big fishing industry in Greenland, an alternative use for discarded fishing nets would have a decreasing effect on the amount of marine litter in the Arctic. A use...... for discarded fishing nets could be as fiber-reinforced polymer (FRP) composites for near surface mounted reinforcement (NSMR). NSMR prolongs the lifetime of existing structures, and thus reduces the amount of materials transported to Greenland, reducing CO2-emission and expenses. The effect of NSMR FRP bars...

  8. Recycled fishing nets as reinforcement of existing concrete structures

    DEFF Research Database (Denmark)

    Sigvardsen, Nina Marie; Bonnerup, Amanda Helena; Ottosen, Lisbeth M.

    2016-01-01

    made from discarded fishing nets is examined with regards to the formation of cracks, load and failure of the beam. Results show a tendency for beams with NSMR FRP bars to prolong the linear elastic region, thus postponing the formation of cracks. Further, a tendency for reducing the formation...... for discarded fishing nets could be as fiber-reinforced polymer (FRP) composites for near surface mounted reinforcement (NSMR). NSMR prolongs the lifetime of existing structures, and thus reduces the amount of materials transported to Greenland, reducing CO2-emission and expenses. The effect of NSMR FRP bars...

  9. Waste Heat Recovery and Recycling in Thermal Separation Processes: Distillation, Multi-Effect Evaporation (MEE) and Crystallization Processes

    Energy Technology Data Exchange (ETDEWEB)

    Emmanuel A. Dada; Chandrakant B. Panchal; Luke K. Achenie; Aaron Reichl; Chris C. Thomas

    2012-12-03

    Evaporation and crystallization are key thermal separation processes for concentrating and purifying inorganic and organic products with energy consumption over 1,000 trillion Btu/yr. This project focused on a challenging task of recovering low-temperature latent heat that can have a paradigm shift in the way thermal process units will be designed and operated to achieve high-energy efficiency and significantly reduce the carbon footprint as well as water footprint. Moreover, this project has evaluated the technical merits of waste-heat powered thermal heat pumps for recovery of latent heat from distillation, multi-effect evaporation (MEE), and crystallization processes and recycling into the process. The Project Team has estimated the potential energy, economics and environmental benefits with the focus on reduction in CO2 emissions that can be realized by 2020, assuming successful development and commercialization of the technology being developed. Specifically, with aggressive industry-wide applications of heat recovery and recycling with absorption heat pumps, energy savings of about 26.7 trillion Btu/yr have been estimated for distillation process. The direct environmental benefits of this project are the reduced emissions of combustible products. The estimated major reduction in environmental pollutants in the distillation processes is in CO2 emission equivalent to 3.5 billion lbs/year. Energy consumption associated with water supply and treatments can vary between 1,900 kWh and 23,700 kWh per million-gallon water depending on sources of natural waters [US DOE, 2006]. Successful implementation of this technology would significantly reduce the demand for cooling-tower waters, and thereby the use and discharge of water treatment chemicals. The Project Team has also identified and characterized working fluid pairs for the moderate-temperature heat pump. For an MEE process, the two promising fluids are LiNO3+KNO3+NANO3 (53:28:19 ) and LiNO3+KNO3+NANO2

  10. Waste Heat Recovery and Recycling in Thermal Separation Processes: Distillation, Multi-Effect Evaporation (MEE) and Crystallization Processes

    Energy Technology Data Exchange (ETDEWEB)

    Emmanuel A. Dada; Chandrakant B. Panchal; Luke K. Achenie; Aaron Reichl; Chris C. Thomas

    2012-12-03

    Evaporation and crystallization are key thermal separation processes for concentrating and purifying inorganic and organic products with energy consumption over 1,000 trillion Btu/yr. This project focused on a challenging task of recovering low-temperature latent heat that can have a paradigm shift in the way thermal process units will be designed and operated to achieve high-energy efficiency and significantly reduce the carbon footprint as well as water footprint. Moreover, this project has evaluated the technical merits of waste-heat powered thermal heat pumps for recovery of latent heat from distillation, multi-effect evaporation (MEE), and crystallization processes and recycling into the process. The Project Team has estimated the potential energy, economics and environmental benefits with the focus on reduction in CO2 emissions that can be realized by 2020, assuming successful development and commercialization of the technology being developed. Specifically, with aggressive industry-wide applications of heat recovery and recycling with absorption heat pumps, energy savings of about 26.7 trillion Btu/yr have been estimated for distillation process. The direct environmental benefits of this project are the reduced emissions of combustible products. The estimated major reduction in environmental pollutants in the distillation processes is in CO2 emission equivalent to 3.5 billion lbs/year. Energy consumption associated with water supply and treatments can vary between 1,900 kWh and 23,700 kWh per million-gallon water depending on sources of natural waters [US DOE, 2006]. Successful implementation of this technology would significantly reduce the demand for cooling-tower waters, and thereby the use and discharge of water treatment chemicals. The Project Team has also identified and characterized working fluid pairs for the moderate-temperature heat pump. For an MEE process, the two promising fluids are LiNO3+KNO3+NANO3 (53:28:19 ) and LiNO3+KNO3+NANO2

  11. Detailed modelling of photon recycling: application to GaAs solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Balenzategui, J.L. [CIEMAT, Division de Energias Renovables, Avda. Complutense, 22, E-28040 Madrid (Spain); Marti, A. [Instituto de Energia Solar, ETSIT, UPM, Ciudad Universitaria s/n, E-28040 Madrid (Spain)

    2006-05-05

    The re-absorption of photons emitted in a semiconductor material as a consequence of radiative recombinations, a process referred to as photon recycling (PR), has been researched into for several decades because of its primary influence in increasing the minority carrier lifetime and related parameters. Solar cells with direct bandgap materials and high-absorption coefficients are firm candidates to show PR effects, leading to an improvement in the conversion efficiency of up to 1-2% in absolute terms for cells with conventional designs. However, the formal modelling of PR effects requires the inclusion of additional terms in the standard set of semiconductor equations and researchers usually tend to neglect its influence, because of the lack of available tools for an easy evaluation of this phenomenon in their particular devices. This paper describes a detailed model of PR which allows the incorporation of specific characteristics and optics of GaAs solar cells and, at the same time, solves some of the problems found in previous developments of these numerical models. The methodology for the calculation is based on the use of commercially available programs for semiconductor device simulation that do not initially have the potential for PR modelling and, thus, it can be extended to and applied by other researchers whishing to compare its relative influence on the performance of different structures and materials. (author)

  12. Laser-induced breakdown spectroscopy application to control of the process of precious metal recovery and recycling

    Science.gov (United States)

    Legnaioli, S.; Lorenzetti, G.; Pardini, L.; Palleschi, V.; Pace, D. M. Diaz; Garcia, F. Anabitarte; Grassi, R.; Sorrentino, F.; Carelli, G.; Francesconi, M.; Francesconi, F.; Borgogni, R.

    2012-05-01

    In this paper, we discuss the application of laser-induced breakdown spectroscopy to precious metal alloys used for the control of the process of recovery and recycling of scraps and waste of industrial processes. In particular, the possibility to obtain sensitivity and trueness comparable to the current systems used in industrial environment in the quantitative determination of the elements of interest was explored. The present study demonstrates that laser-induced breakdown spectroscopy can be considered as a viable alternative to inductively coupled plasma optical emission spectrometry and X-ray fluorescence spectroscopy for the determination of recovered precious metals. The limits of detection obtained are of the order of 0.2 mg/g for all the elements considered. The maximum deviation with respect to the nominal concentrations is around 1 mg/g at concentrations around 20 mg/g (gold) corresponding to a relative error slightly higher than ± 5%.

  13. Recycling process of Mn-Al doped large grain UO{sub 2} pellets

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Ik Hui; Yang, Jae Ho; Rhee, Young Woo; Kim, Dong Joo; Kim, Jong Hun; Kim, Keon Sik; Song, Kun Woo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-10-15

    To reduce the fuel cycle costs and the total mass of spent light water reactor (LWR) fuels, it is necessary to extend the fuel discharged burn-up. Research on fuel pellets focuses on increasing the pellet density and grain size to increase the uranium contents and the high burnup safety margins for LWRs. KAERI are developing the large grain UO{sub 2} pellet for the same purpose. Small amount of additives doping technology are used to increase the grain size and the high temperature deformation of UO{sub 2} pellets. Various promising additive candidates had been developed during the last 3 years and the MnO-Al{sub 2}O{sub 3} doped UO{sub 2} fuel pellet is one of the most promising candidates. In a commercial UO{sub 2} fuel pellet manufacturing process, defective UO{sub 2} pellets or scraps are produced and those should be reused. A common recycling method for defective UO{sub 2} pellets or scraps is that they are oxidized in air at about 450 .deg. C to make U{sub 3}O{sub 8} powder and then added to UO{sub 2} powder. In the oxidation of a UO{sub 2} pellet, the oxygen propagates along the grain boundary. The U{sub 3}O{sub 8} formation on the grain boundary causes a spallation of the grains. So, size and shape of U{sub 3}O{sub 8} powder deeply depend on the initial grain size of UO{sub 2} pellets. In the case of Mn-Al doped large grain pellets, the average grain size is about 45{mu}m and about 5 times larger than a typical un-doped UO{sub 2} pellet which has grain size of about 8{approx}10{mu}m. That big difference in grain size is expected to cause a big difference in recycled U{sub 3}O{sub 8} powder morphology. Addition of U{sub 3}O{sub 8} to UO{sub 2} leads to a drop in the pellet density, impeding a grain growth and the formation of graph- like pore segregates. Such degradation of the UO{sub 2} pellet properties by adding the recycled U{sub 3}O{sub 8} powder depend on the U{sub 3}O{sub 8} powder properties. So, it is necessary to understand the property and its

  14. Scientific Opinion on the safety assessment of the process SOREPET GR based on EREMA Basic technology used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2014-04-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the recycling process SOREPET GR (EU register No RECYC073 which is based on the EREMA Basic technology. The input to the process is hot caustic washed and dried poly(ethylene terephthalate (PET flakes originating from collected post-consumer PET containers, mainly bottles and containing no more than 5 % PET from non-food consumer applications. In this process, washed and dried PET flakes are heated in a continuous reactor under vacuum before being extruded. Having examined the results of the challenge test provided, the Panel concluded that the continuous reactor is the critical step that determines the decontamination efficiency of the process. The operating parameters to control its performance are well defined and are temperature, pressure and residence time. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below the modelled migration of 0.1 μg/kg food derived from the exposure scenario for infants and 0.15 μg/kg food derived from the exposure scenario for toddlers. The Panel concluded that recycled PET obtained from the process is not of safety concern when used to manufacture articles intended for food contact materials applications in compliance with the conditions as specified in the conclusion of the opinion.

  15. The recycling industries : a Canadian perspective

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, L. [CARI, Almonte, ON (Canada); Lakshmanan, V.I. [Ortech International, Mississauga, ON (Canada)

    2000-07-01

    The economic and environmental benefits that the recycling sector has to offer in terms of resource conservation benefits was discussed with particular focus on the synergies that exist between major mining and metallurgical industries and end users. The main objective of recycling is to conserve natural resources, reducing primary process waste as well as air and water effluent generated by these processes. Recycling provides energy conservation, creates jobs and reduces the demand for sanitary landfills. The main concerns that exist within the recycling industry is the government's actions through laws, regulations and taxes which sometimes discourage recycling. The need for the public to become more informed about the benefits of recycling was emphasized. It was also noted that manufacturers should consider the final disposition of a product in their product design and manufacture. 1 tab.

  16. Chemical Recycle of Plastics

    Directory of Open Access Journals (Sweden)

    Sara Fatima

    2014-11-01

    Full Text Available Various chemical processes currently prevalent in the chemical industry for plastics recycling have been discussed. Possible future scenarios in chemical recycling have also been discussed. Also analyzed are the effects on the environment, the risks, costs and benefits of PVC recycling. Also listed are the various types of plastics and which plastics are safe to use and which not after rcycle

  17. A novel full recycling process through two-stage anaerobic treatment of distillery wastewater for bioethanol production from cassava.

    Science.gov (United States)

    Zhang, Qing-Hua; Lu, Xin; Tang, Lei; Mao, Zhong-Gui; Zhang, Jian-Hua; Zhang, Hong-Jian; Sun, Fu-Bao

    2010-07-15

    In the present study, a novel full recycling process for bioethanol production was investigated, where three mathematical models were established to simulate the accumulation of major soluble inhibitory substances, including organic compounds, total ions, volatile fatty acids (VFAs) and colorants. These inhibitory substances in the reused water reached a relative steady state after 3-7 batches of anaerobic treatment and recycling process, which coincided with the results of mathematical models. There were no negative effects of these inhibitory substances on ethanol fermentation and the final ethanol yield, fermentation time, starch utilization ratio were very close to that of the conventional process using tap water. However, approximately 7.54% (w/w) of water was lost during each circulation, which was replenished in subsequent circulations, to assure consistent fermentation broth volume. This novel process was confirmed to have a stable operation over 13 recycles. It is concluded the stable states of the inhibitory substances in the reused water can assure this recycling process will run successfully.

  18. Scientific Opinion on the safety evaluation of the process “PETUK SSP” for production of recycled post-consumer PET for use in food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2012-08-01

    Full Text Available

    This scientific opinion of EFSA deals with the safety evaluation of the recycling process PETUK SSP, EC register number RECYC004. Through this process, washed PET flakes are dried, extruded into pellets then fed to a solid state polymerisation (SSP reactor where high temperature and long residence time are applied under vacuum. After having examined the challenge test provided, the Panel concluded that the SSP is the critical step that determines the decontamination efficiency of the process. The operating parameters to control the performance of this critical step are the temperature, the pressure and the residence time. It was demonstrated, by means of the challenge test, that the recycling process under evaluation is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore, the Panel considered that the recycling process PETUK SSP is able to reduce any foreseeable accidental contamination of the post-consumer food contact PET to a concentration that does not give rise to concern for a risk to human health if:

    1. it is operated under conditions that are at least as severe as those obtained from the challenge test used to measure the decontamination efficiency of the processes and
    2. the input is washed and dried post-consumer PET flakes originating from materials and articles that have been manufactured in accordance with the Community legislation on food contact materials containing no more than 5% of PET from non-food consumer applications.

    The Panel concluded that the recycled PET obtained from the process PETUK SSP intended for the manufacture of materials and articles for contact with all types of foodstuffs for long term storage at room temperature, with or without hotfill is not considered of safety concern.

  19. Scientific Opinion on the safety assessment of the process "MKF-Ergis", used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2014-05-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the recycling process MKF-Ergis, EU register number RECYC021. The input for the process (step 1 is washed and dried PET flakes originating from collected post-consumer PET bottles containing no more than 1 % of PET from non-food consumer applications. The washed and dried flakes are crystallised (step 2 and then extruded at high temperature under vacuum into films (step 3. Having examined the challenge test provided, the Panel concluded that the two steps, the crystallisation (step 2 and the extrusion (step 3 are the critical steps that determine the decontamination efficiency of the process. The operating parameters to control their performance are well defined and are temperature, gas flow and residence time for the crystallisation and temperature, vacuum and residence time for the extrusion. The operating parameters of these steps in the process are at least as severe as those used in the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore the Panel concluded that the recycled PET obtained from this process intended for the manufacture of materials and articles for contact with all types of foodstuffs for long term storage at room temperature, with or without hotfill is not considered of safety concern. Trays made of this recycled PET should not be used in microwave and conventional ovens.

  20. Recycling of asbestos tailings used as reinforcing fillers in polypropylene based composites.

    Science.gov (United States)

    Zhai, Wensi; Wang, Yao; Deng, Yuan; Gao, Hongli; Lin, Zhen; Li, Mao

    2014-04-15

    In this work, asbestos tailings were recycled and used as reinforcing fillers to enhance the mechanical properties of polypropylene (PP). A silane coupling agent was used to chemically modify the asbestos tailings to increase the compatibility between asbestos tailings and polypropylene matrix. Both raw and chemically treated asbestos tailings with different loading levels (from 3 to 30 wt%) were utilized to fabricate composites. Mechanical properties of these composites have been investigated by dynamic mechanical analysis, tensile test and notched impact test. Results showed that hybridization of asbestos tailings in the composites enhanced the mechanical properties of neat PP evidently, and treated asbestos tailings/PP composites yielded even better mechanical properties compared with those of raw asbestos tailings/PP composites. This recycling method of asbestos tailings not only reduces disposal costs and avoids secondary pollution but also produces a new PP-based composite material with enhanced mechanical properties.

  1. The effects of magmatic processes and crustal recycling on the molybdenum stable isotopic composition of Mid-Ocean Ridge Basalts

    Science.gov (United States)

    Bezard, Rachel; Fischer-Gödde, Mario; Hamelin, Cédric; Brennecka, Gregory A.; Kleine, Thorsten

    2016-11-01

    Molybdenum (Mo) stable isotopes hold great potential to investigate the processes involved in planetary formation and differentiation. However their use is currently hampered by the lack of understanding of the dominant controls driving mass-dependent fractionations at high temperature. Here we investigate the role of magmatic processes and mantle source heterogeneities on the Mo isotope composition of Mid-Ocean Ridges Basalts (MORBs) using samples from two contrasting ridge segments: (1) the extremely fast spreading Pacific-Antarctic (66-41°S) section devoid of plume influence and; (2) the slow spreading Mohns-Knipovich segment (77-71°N) intercepted by the Jan Mayen Plume (71°N). We show that significant variations in Mo stable isotope composition exist in MORBs with δ98/95Mo ranging from - 0.24 ‰ to + 0.15 ‰ (relative to NIST SRM3134). The absence of correlation between δ98/95Mo and indices of magma differentiation or partial melting suggests a negligible impact of these processes on the isotopic variations observed. On the other hand, the δ98/95Mo variations seem to be associated with changes in radiogenic isotope signatures and rare earth element ratios (e.g., (La/Sm)N), suggesting mantle source heterogeneities as a dominant factor for the δ98/95Mo variations amongst MORBs. The heaviest Mo isotope compositions correspond to the most enriched signatures, suggesting that recycled crustal components are isotopically heavy compared to the uncontaminated depleted mantle. The uncontaminated depleted mantle shows slightly sub-chondritic δ98/95Mo, which cannot be produced by core formation and, therefore, more likely result from extensive anterior partial melting of the mantle. Consequently, the primitive δ98/95Mo composition of the depleted mantle appears overprinted by the effects of both partial melting and crustal recycling.

  2. Management options for recycling radioactive scrap metals

    Energy Technology Data Exchange (ETDEWEB)

    Dehmel, J.C.; MacKinney, J.; Bartlett, J.

    1997-02-01

    The feasibility and advantages of recycling radioactive scrap metals (RSM) have yet to be assessed, given the unique technical, regulatory, safety, and cost-benefit issues that have already been raised by a concerned recycling industry. As is known, this industry has been repeatedly involved with the accidental recycling of radioactive sources and, in some cases, with costly consequences. If recycling were deemed to be a viable option, it might have to be implemented with regulatory monitoring and controls. Its implementation may have to consider various and complex issues and address the requirements and concerns of distinctly different industries. There are three basic options for the recycling of such scraps. They are: (1) recycling through the existing network of metal-scrap dealers and brokers, (2) recycling directly and only with specific steelmills, or (3) recycling through regional processing centers. Under the first option, scrap dealers and brokers would receive material from RSM generators and determine at which steelmills such scraps would be recycled. For the second option, RSM generators would deal directly with selected steelmills under specific agreements. For the third option, generators would ship scraps only to regional centers for processing and shipment to participating steelmills. This paper addresses the potential advantages of each option, identifies the types of arrangements that would need to be secured among all parties, and attempts to assess the receptivity of the recycling industry to each option.

  3. Microwave based oxidation process for recycling the off-specification (U,Pu)O2 fuel pellets

    Science.gov (United States)

    Singh, G.; Khot, P. M.; Kumar, Pradeep; Bhatt, R. B.; Behere, P. G.; Afzal, Mohd

    2017-02-01

    This paper reports development of a process named MicroWave Direct Oxidation (MWDO) for recycling the off-specification (U,Pu)O2 mixed oxide (MOX) fuel pellets generated during fabrication of typical fast reactor fuels. MWDO is a two-stage, single-cycle process based on oxidative pulverisation of pellets using 2450 MHz microwave. The powder sinterability was evaluated by bulk density and BET specific surface area. The oxidised powders were analyzed for phases using XRD and stoichiometry by thermogravimetry. The sinterability was significantly enhanced by carrying out oxidation in higher oxygen partial pressure and by subjecting MOX to multiple micronisation-oxidation cycles. After three cycles, the recycled powder from (U,28%Pu)O2 resulted surface area >3 m2/g and 100% re-used for MOX fabrication. The flow sheet was developed for maximum utilization of recycled powder describable by a parameter called Scrap Recycling Ratio (SRR). The process demonstrates smaller processing cycle, better powder properties and higher oxidative pulverisation over conventional method.

  4. Recycling and processing of several typical crosslinked polymer scraps with enhanced mechanical properties based on solid-state mechanochemical milling

    Science.gov (United States)

    Lu, Canhui; Zhang, Xinxing; Zhang, Wei

    2015-05-01

    The partially devulcanization or de-crosslinking of ground tire rubber (GTR), post-vulcanized fluororubber scraps and crosslinked polyethylene from cable scraps through high-shear mechanochemical milling (HSMM) was conducted by a modified solid-state mechanochemical reactor. The results indicated that the HSMM treated crosslinked polymer scraps can be reprocessed as virgin rubbers or thermoplastics to produce materials with high performance. The foamed composites of low density polyethylene/GTR and the blend of post-vulcanized flurorubber (FKM) with polyacrylate rubber (ACM) with better processability and mechanical properties were obtained. The morphology observation showed that the dispersion and compatibility between de-crosslinked polymer scraps and matrix were enhanced. The results demonstrated that HSMM is a feasible alternative technology for recycling post-vulcanized or crosslinked polymer scraps.

  5. Recycling and processing of several typical crosslinked polymer scraps with enhanced mechanical properties based on solid-state mechanochemical milling

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Canhui; Zhang, Xinxing; Zhang, Wei [State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute, Sichuan University, Chengdu 610065 (China)

    2015-05-22

    The partially devulcanization or de-crosslinking of ground tire rubber (GTR), post-vulcanized fluororubber scraps and crosslinked polyethylene from cable scraps through high-shear mechanochemical milling (HSMM) was conducted by a modified solid-state mechanochemical reactor. The results indicated that the HSMM treated crosslinked polymer scraps can be reprocessed as virgin rubbers or thermoplastics to produce materials with high performance. The foamed composites of low density polyethylene/GTR and the blend of post-vulcanized flurorubber (FKM) with polyacrylate rubber (ACM) with better processability and mechanical properties were obtained. The morphology observation showed that the dispersion and compatibility between de-crosslinked polymer scraps and matrix were enhanced. The results demonstrated that HSMM is a feasible alternative technology for recycling post-vulcanized or crosslinked polymer scraps.

  6. Dining at the periodic table: metals concentrations as they relate to recycling.

    Science.gov (United States)

    Johnson, Jeremiah; Harper, E M; Lifset, Reid; Graedel, T E

    2007-03-01

    A correlation between the prices of a variety of substances and their dilutions in their initial matrices was shown in 1959 by T.K. Sherwood. The research presented here shows that the relationship holds for engineering metals today, which we termed the metals-specific Sherwood plot. The concentrations of metals in products (e.g., printed wiring boards and automobiles) and waste streams (e.g., municipal solid waste, and construction and demolition debris) were plotted with this correlation. In addition, for the products and waste streams that undergo disassembly at end-of-life, the metals concentrations of the disassembled components were also plotted. It was found that most of the metals that are currently targeted for recycling have post-disassembly concentrations that lie above the metals-specific Sherwood plot (i.e., have concentrations that are more enriched than minimum profitable ore grades). This suggests that material concentration plays a role in the viability of recycling at end-of-life. As products grow in complexity and the variety of materials used, analyses such as this one provide insight for policymakers and those interested in material sustainability into macro-level trends of material use and future recycling practices.

  7. An assessment on the recycling opportunities of wastes emanating from scrap metal processing in Mauritius

    Energy Technology Data Exchange (ETDEWEB)

    Mauthoor, Sumayya, E-mail: sumayya.mauthoor@umail.uom.ac.mu [Department of Chemical and Environmental Engineering, University of Mauritius, Réduit (Mauritius); Mohee, Romeela [Professor of Chemical and Environmental Engineering, National Research Chair in Solid Waste Management, Mauritius Research Council (Mauritius); Kowlesser, Prakash [Solid Waste/Beach Management Unit, Ministry of Local Government and Outer Islands (Mauritius)

    2014-10-15

    Highlights: • Scrap metal processing wastes. • Areas of applications for slag, electric arc furnace dust, mill scale and wastewater sludge. • Waste generation factor of 349.3 kg per ton of steel produced. • Waste management model. - Abstract: This paper presents an assessment on the wastes namely slag, dust, mill scale and sludge resulting from scrap metal processing. The aim of this study is to demonstrate that there are various ways via which scrap metal processing wastes can be reused or recycled in other applications instead of simply diverting them to the landfill. These wastes are briefly described and an overview on the different areas of applications is presented. Based on the results obtained, the waste generation factor developed was 349.3 kg per ton of steel produced and it was reported that slag represents 72% of the total wastes emanating from the iron and steel industry in Mauritius. Finally the suitability of the different treatment and valorisation options in the context of Mauritius is examined.

  8. Comparative Study on Mechanical Properties between Pure and Recycled Polypropylenes

    Directory of Open Access Journals (Sweden)

    Ariadne L. Juwono

    2010-04-01

    Full Text Available Polypropylene (PP is one type of thermoplastics that is widely used in our daily activities. A combination of the high demand and the easiness of recycling process, the recycled PP has been generally applied. In this study, the structure and the mechanical properties of the as-received PPs, recycled PPs, and commercial recycled PPs were compared, especially for cloth hanger application. DSC test results showed that recycling process did not cause a significant change to the material's melting point, which stayed in a range of 160-163 oC. Meanwhile, FTIR test results showed that the commercial recycled PPs contained of Polyethylene (PE, which was not found in the as-received and the recycled PPs. Tensile and hardness tests demonstrated that there were no significant differences between the as-received and recycled PPs. In contrast, tensile test results of the commercial recycled PPs showed that the tensile strength, Young modulus and strain-at-break were lower than those of the as-received PPs by 22.1%, 8.1% and 65.7% respectively. The hardness test results of the commercial recycled PPs showed that the recycling process had a little effect on the material's hardness. These facts were supported by SEM observation on the surface that the contour of the commercial recycled PPs was relatively flatter and had smaller grain size than those of the as-received PPs. This indicated that the commercial recycled PPs were more brittle compared to the recycled PPs. To conclude, the recycled PPs have similar properties to the as-received PPs so that recycled PPs are suitable to be applied as cloth hanger application.

  9. Downsides of the recycling process: harmful organic chemicals in children's toys.

    Science.gov (United States)

    Ionas, Alin C; Dirtu, Alin C; Anthonissen, Tim; Neels, Hugo; Covaci, Adrian

    2014-04-01

    Most of the materials used in consumer goods contain a number of additives which are meant to improve key properties like plasticity or flame resistance. At the end-of-life of the product, many polymeric materials are recycled and the additives they contain, such as flame retardants (FRs) and plasticizers, are transferred to the newly manufactured goods. We have investigated the occurrence and profiles of FRs, such as polybrominated diphenyl ethers (PBDEs) and phosphate FR (PFRs) and of plasticisers, such as phthalate esters, in 106 toys samples. Low levels and detection frequencies of components of the technical Penta-BDE and Deca-BDE mixtures were found, with BDE 209 being the dominant PBDE in all samples (maximum value was 0.14mg/g or 0.014%). The levels of PFRs and phthalates were up to 10,000 times higher than those of the PBDEs, with triphenyl phosphate and diethylhexyl phthalate being the major representatives of these classes. Maximum values were 1.3 and 6.9%, respectively. The detection frequencies were up to 50% for PFRs and 98% for phthalates. All but one of the toys produced after the REACH regulation went into force complied with its provisions. The samples were grouped according to relevant selection criteria to assess the risk for children of different age groups. Using models in the literature, exposure to these chemicals was tentatively assessed. It is clear that at the levels found in the investigated toys, these additives do not contribute to the intended characteristics of the materials, but in some cases may pose a health hazard to the children. Most likely, recycled materials are an important source of these additives in toys and therefore, their (re)use in products for children should be subject to stricter restrictions.

  10. Toxicity assessment and feasible recycling process for amorphous silicon and CIS waste photovoltaic panels.

    Science.gov (United States)

    Savvilotidou, Vasiliki; Antoniou, Alexandra; Gidarakos, Evangelos

    2017-01-01

    End-of-Life (EoL) photovoltaic (P/V) modules, which are recently included in the 2012/19/EU recast, require sound and sustainable treatment. Under this perspective, this paper deals with 2nd generation P/V waste modules, known as thin-film, via applying chemical treatment techniques. Two different types of modules are examined: (i) tandem a-Si:H/μc-Si:H panel and, (ii) Copper-Indium-Selenide (CIS) panel. Panels' pretreatment includes collection, manual dismantling and shredding; pulverization and digestion are further conducted to identify their chemical composition. A variety of elements is determined in the samples leachates' after both microwave-assisted total digestion and Toxicity Characteristic Leaching Procedure (TCLP test) using Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) analysis. The analysis reveals that several elements are detected in the two of panels, with no sample exceeds the TCLP test. Concentrations of precious and critical metals are also measured, which generates great incentives for recovery. Then, further experiments, for P/V recycling investigation, are presented using different acids or acid mixtures under a variety of temperatures and a stable S/L ratio, with or without agitation, in order to determine the optimal recycling conditions. The results verify that chemical treatment in P/V shredded samples is efficient since driving to ethylene-vinyl acetate (EVA) resin's dissolution, as well as valuable structural materials recovery (P/V glass, ribbons, cells, P/V intermediate layers). Among the solvents used, sulfuric acid and lactic acid demonstrate the most efficient and strongest performance on panels' treatment at gentle temperatures providing favorably low energy requirements.

  11. Remaking Waste as Water: The Governance of Recycled Effluent for Potable Water Supply

    Directory of Open Access Journals (Sweden)

    Katharine Meehan

    2013-02-01

    Full Text Available Water managers increasingly rely on the indirect potable reuse (IPR of recycled effluent to augment potable water supplies in rapidly growing cities. At the same time, the presence of waste – as abject material – clearly remains an object of concern in IPR projects, spawning debate and opposition among the public. In this article, we identify the key governance factors of IPR schemes to examine how waste disrupts and stabilises existing practices and ideologies of water resources management. Specifically, we analyse and compare four prominent IPR projects from the United States and Australia, and identify the techno-scientific, legal, and socio-economic components necessary for successful implementation of IPR projects. This analysis demonstrates that successful IPR projects are characterised by large-scale, centralised infrastructure, state and techno-scientific control, and a political economy of water marked by supply augmentation and unchecked expansion. We argue that – despite advanced treatment – recycled effluent is a parallax object: a material force that disrupts the power geometries embedded in municipal water management. Consequently, successful IPR schemes must stabilise a particular mode of water governance, one in which recycled effluent is highly regulated and heavily policed. We conclude with insights about the future role of public participation in IPR projects.

  12. A challenging project. Recycling process of lithium ion accumulators for vehicles in comparison; Gewichtige Angelegenheit. Recyclingverfahren von Li-Ion-Akkus fuer Fahrzeuge im Vergleich

    Energy Technology Data Exchange (ETDEWEB)

    Buchert, Matthias [Oeko-Institut e.V., Darmstadt (Germany)

    2012-08-15

    The electromobility closely is associated with the use of lithium-ion batteries with high performance. In the case of a targeted market penetration of electric motors in the automotive industry in Europe this represents an advent of more than a hundred thousand tons of waste batteries annually in the medium and long term. These batteries contain important metals such as lithium, cobalt or nickel. These batteries recycling processes are being developed.

  13. Fly ash. Quality recycling material

    Energy Technology Data Exchange (ETDEWEB)

    Blomster, D.; Leisio, C.

    1996-11-01

    Imatran Voima`s coal-fired power plants not only generate power and heat but also produce fly ash which is suitable raw material for recycling. This material for recycling is produced in the flue gas cleaning process. It is economical and, thanks to close quality control, is suitable for use as a raw material in the building materials industry, in asphalt production, and in earthworks. Structures made from fly ash are also safe from an environmental point of view. (orig.)

  14. Recycling industrial architecture : the redefinition of the recycling principles in the context of sustainable architectural design

    OpenAIRE

    Šijaković, Milan

    2015-01-01

    The aim of this thesis is the elucidation of the concept of architectural recycling as an environmentally sustainable alternative to demolition and preservation. More precisely, the research aim relates to the redefinition of recycling design principles in the context of the sustainable architectural design. The process of architectural recycling was placed in the context of a sustainable architectural design, as the global concept of sustainable development is imposed as a general context fo...

  15. Microbial carbon recycling - an underestimated process controlling soil carbon dynamics - Part 1: A long-term laboratory incubation experiment

    Science.gov (United States)

    Basler, A.; Dippold, M.; Helfrich, M.; Dyckmans, J.

    2015-10-01

    Independent of its chemical structure carbon (C) persists in soil for several decades, controlled by stabilization and recycling. To disentangle the importance of the two factors on the turnover dynamics of soil sugars, an important compound of soil organic matter (SOM), a 3-year incubation experiment was conducted on a silty loam soil under different types of land use (arable land, grassland and forest) by adding 13C-labelled glucose. The compound-specific isotope analysis of soil sugars was used to examine the dynamics of different sugars during incubation. Sugar dynamics were dominated by a pool of high mean residence times (MRT) indicating that recycling plays an important role for sugars. However, this was not substantially affected by soil C content. Six months after label addition the contribution of the label was much higher for microbial biomass than for CO2 production for all examined land use types, corroborating that substrate recycling was very effective within the microbial biomass. Two different patterns of tracer dynamics could be identified for different sugars: while fucose and mannose showed highest label contribution at the beginning of the incubation with a subsequent slow decline, galactose and rhamnose were characterized by slow label incorporation with subsequently constant levels, which indicates that recycling is dominating the dynamics of these sugars. This may correspond to (a) different microbial growing strategies (r and K-strategist) or (b) location within or outside the cell membrane (lipopolysaccharides vs. exopolysaccharides) and thus be subject of different re-use within the microbial food web. Our results show how the microbial community recycles substrate very effectively and that high losses of substrate only occur during initial stages after substrate addition. This study indicates that recycling is one of the major processes explaining the high MRT observed for many SOM fractions and thus is crucial for understanding the

  16. Material recycling of post-consumer polyolefin bulk plastics: Influences on waste sorting and treatment processes in consideration of product qualities achievable.

    Science.gov (United States)

    Pfeisinger, Christian

    2017-02-01

    Material recycling of post-consumer bulk plastics made up of polyolefins is well developed. In this article, it is examined which effects on waste sorting and treatment processes influence the qualities of polyolefin-recyclats. It is shown that the properties and their changes during the product life-cycle of a polyolefin are defined by its way of polymerisation, its nature as a thermoplast, additives, other compound and composite materials, but also by the mechanical treatments during the production, its use where contact to foreign materials is possible and the waste sorting and treatment processes. Because of the sum of the effects influencing the quality of polyolefin-recyclats, conclusions are drawn for the material recycling of polyolefins to reach high qualities of their recyclats. Also, legal requirements like the EU regulation 1907/2006 concerning the registration, evaluation, authorisation and restrictions on chemicals are considered.

  17. Efficient CN Formation for Preparingα-Branched Primary Amines by Recycled Intramolecular Reactions of 1,8-Naphthosultone Using Ammonia as Nitrogen Source

    Institute of Scientific and Technical Information of China (English)

    周新锐; 陈洁; 曾小萍; 刘季红; Istvan E.Mark

    2014-01-01

    Amination of tertiary and secondary alcohols using aqueous ammonia as nitrogen source was carried out by a process with recyclable intramolecular reaction of 1,8-naphthosultone, which lead to α-branched primary amines. Sulfonic resin serves as the heterogeneous catalyst for CN bond formation and protects the neighboring hydroxyl group until the required hydrolysis starts in the alkaline solution. The process can be conducted under mild conditions, no additional solvent is needed and no overreaction to secondary or tertiary amines occurs.

  18. Thermal recycling of plastic waste using pyrolysis-gasification process for energy production

    Energy Technology Data Exchange (ETDEWEB)

    Forbit, George Teke

    2012-04-04

    waste management organisations and disposal sites were conducted in various cities in the three case study countries. A resource-oriented manual sorting using the resource-recovery scavenging approach (RESA) simulating integration of scavenger's activities in waste sorting was conducted at BTU and Lagos. Major results obtained include: Characterization, quantification and classification of a dry sample of commingled MSW at Cottbus gave major waste fractions in order of decreasing abundance as 23.15% of residue waste, 19.75% of paper and cardboards, 17.80% of plastics, 14.63% of textiles and diapers, 10.06% of food waste and 9.55% of glass. An overall 33.21% of waste sample is compostable for manure, 52.2% usable as feedstock in the PG technology and 99.81% of total sample having a material or energy recovery potential. In Lagos, Nigeria main fractions were 29% of plastics, 36% of residue waste, 17% of soil/sand, 7% of paper with overall 41% usable as feedstock in PG technology, 39% compostable, 3% of recyclable (metal and glass). Sand can be recovered from the soil/sand fraction for construction. Excluding the sand/soil mixture, 83% of the total waste sample has potential for material and energy value. An appropriate technology that applies principles of pyrolysis and gasification to convert non-PVC plastic waste to energy was designed, constructed, tested and optimized with respect to: (i) Successful functioning with conversion of averagely 98.51% of input constituting of 82.78-98.21% of charcoal and 96.72-99.27% of plastic to heat energy (ii) Evaluation of socioeconomic and environmental impacts based on pyrolysis and exhaust gas and ash residue analysis showed absence of VOCs, heavy metals and pollutant organic and inorganic compounds; (iii) Safety and risk assessment to indoor pollution is very low; (iv) Assessment of the WTA and WTP indicated that 94% of respondents in Lagos, Nigeria and Porto Novo, Benin were willing to accept and pay for this technology

  19. Bacterial counts on teat skin and in new sand, recycled sand, and recycled manure solids used as bedding in freestalls.

    Science.gov (United States)

    Rowbotham, R F; Ruegg, P L

    2016-08-01

    On modern dairy farms, environmental mastitis pathogens are usually the predominant cause of mastitis, and bedding often serves as a point of exposure to these organisms. The objective of this longitudinal study was to determine bacterial populations of 4 different bedding types [deep-bedded new sand (NES), deep-bedded recycled sand (RS), deep-bedded manure solids (DBMS), and shallow-bedded manure solids over foam core mattresses (SBMS)] and of teat skin swabs of primarily primiparous cows housed in a single facility over all 4 seasons. Samples of bedding were collected weekly (n=49wk) from pens that each contained 32 lactating dairy cows. Throughout the length of the same period, composite swabs of teat skin were collected weekly from all cows before and after premilking teat sanitation. Median numbers of streptococci and streptococci-like organisms (SSLO) were >8.6×10(6) cfu/g and >6.9×10(3) cfu/teat swab for all bedding types and teat swabs, respectively. Numbers of SSLO were greatest in samples of SBMS (2.1×10(8) cfu/g) and least in samples of NES (8.6×10(6) cfu/g), RS (1.3×10(7) cfu/g), and DBMS (1.7×10(7) cfu/g). Numbers of gram-negative bacteria in bedding (5.5×10(4) to 1.2×10(7) cfu/g) were fewer than numbers of SSLO (8.6×10(6) to 2.1×10(8) cfu/g). Numbers of coliform bacteria were greatest in samples of DBMS (2.2×10(6) cfu/g) and least in samples of NES (3.6×10(3) cfu/g). In general, the relative number of bacteria on teat skin corresponded to exposure in bedding. Numbers of gram-negative bacteria recovered from prepreparation teat swabs were greatest for cows bedded with DBMS (1.0×10(4) cfu/swab) and RS (2.5×10(3) cfu/swab) and least for cows bedded with NES (5.8×10(2) cfu/swab). Median numbers of coliform and Klebsiella spp. recovered from prepreparation teat swabs were below the limit of detection for all cows except those bedded with DBMS. Numbers of SSLO recovered from prepreparation teat swabs were least for cows bedded with DBMS (6.9

  20. Recycling Paper Recycling

    Directory of Open Access Journals (Sweden)

    Martin A. Hubbe

    2014-02-01

    Full Text Available What do you do after a product has served its function and is no longer needed? Ideally, you recycle it. What do you do if people have neglected or forgotten so much of what has been learned in recent years about paper recycling? Well, one of the things that someone can do is to write a book. Very little of the contents of such a book may be new. But the book itself can be highly valuable, representing a lot of effort to select and organized material that will be helpful for the current and upcoming generations of papermaking technologists. This editorial describes a new book by Dr. Pratima Bajpai entitled Recycling and Deinking of Recovered Paper. Readers who deal with the recycling of paper will probably want to have a copy of it on a handy shelf.

  1. New approaches to recycling tires

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, R.

    1991-03-01

    Steel-belted radial tires are potentially one of the most recyclable products created by modern industry, although the potential has been barely tapped. Discarded tires pile up at an astonishing rate each year - 234 million in the US and 26 million passenger tire equivalents in Canada. They represent a mother lode of raw material waiting for modern day miners to transform them into recycled rubber, steel, fiber and energy. The tremendous increase in use of steel belted radials since the early 1970s has complicated their recyclability compared to the bias ply tire, but it has also accomplished waste reduction by tripling tire service life. Part one of this report describes processes being developed to convert tires to crumb rubber, as well as some potential uses of recycled rubber. Part two, to appear next month, will examine such uses as rubberized athletic tracks and highway asphalt.

  2. Recycle of electrolytically dissolved struvite as an alternative to enhance phosphate and nitrogen recovery from swine wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Liu, YingHao; Kumar, Sanjay [Department of Animal Life System, Kangwon National University, Hyoja 2, 192-1, Chunchon 200-701 (Korea, Republic of); Kwag, JungHoon; Kim, JaeHwan [National Institute of Animal Science, RDA, Suwon 441-350 (Korea, Republic of); Kim, JeongDae [Department of Animal Life System, Kangwon National University, Hyoja 2, 192-1, Chunchon 200-701 (Korea, Republic of); Ra, ChangSix, E-mail: changsix@kangwon.ac.kr [Department of Animal Life System, Kangwon National University, Hyoja 2, 192-1, Chunchon 200-701 (Korea, Republic of)

    2011-11-15

    Highlights: {yields} The struvite dissolution was enhanced with increased NaCl concentration and electric voltage; however 0.06% NaCl and 7 V was considered optimum. {yields} Reaction time of 1.5 h found to be suitable for struvite dissolution and complete NH{sub 4}-N removal. {yields} Struvite dissolution increases with increased struvite amount, but beyond 1.25 g/L of struvite a plateau was reached. {yields} The PO{sub 4}{sup 3-}P and NH{sub 4}-N removal percentage increases significantly (p < 0.01) with increased recycle ratio of dissolved struvite. - Abstract: Operational parameters such as electric voltage, NaCl, reaction time (RT) and initial struvite amount were optimized for struvite dissolution with a designed electrolysis reactor, and the effect of recycling the dissolved solution on the performance of struvite crystallization was also assessed. The electrolytic reactor was made of plexiglas having titanium plate coated with iridium oxide as anode (surface area: 400 cm{sup 2}) and stainless steel plates as cathodes. For reutilization of dissolved struvite, four runs were conducted with different recycle ratio of the solution. Optimum conditions for the electric voltage, NaCl, RT and initial struvite amount were 7 V, 0.06%, 1.5 h and 1.25 g/L, respectively. At the above optimized conditions, 49.17 mg/L phosphate (PO{sub 4}{sup 3-}P) was dissolved and ammonium-nitrogen (NH{sub 4}-N) got completely removed from the solution. When 0.0, 0.5, 1.0 and 2.0 moles of the dissolved struvite with respect to PO{sub 4}{sup 3-}P in swine wastewater were recycled along with 0.5 M magnesium chloride (MgCl{sub 2}), the PO{sub 4}{sup 3-}P removal was 63, 69, 71 and 79%, and NH{sub 4}-N was 9, 31, 40 and 53%, respectively. Hence, the performance of struvite formation process was proportionally increased. It is concluded that struvite can be re-dissolved by electrolysis and reused as a source of P and Mg.

  3. Processing silicon microparticles recycled from wafer waste via Rapid Thermal Process for lithium-ion battery anode materials

    Science.gov (United States)

    Tan, Hui-Gee; Duh, Jenq-Gong

    2016-12-01

    A vast quantity of waste sludge is generated during the silicon wafers slicing process in semiconductor and photovoltaic industries. Turning the waste powder into high-value products is of strategic importance for industrial processes. The purified Si microparticles (Si-MP) are recycled by a simple and fast procedure, Rapid Thermal Process (RTP). A prominent anodic material of Si-MP/Carbon composite with porous structure is obtained via in-spaced carbonization of water-soluble binder sodium carboxymethyl cellulose during RTP. This strategy provides buffer space, which is constructed by carbon porous continuous conductive framework throughout the entire electrode, to resist local stress and intense volume variation. In addition, a sufficiently electrochemically stable solid-electrolyte interphase layer is accomplished with the coating of SiOx film and amorphous carbon on the surface of Si-MP. Under these circumstances, the enhanced electrodes achieve a first cycle efficiency of approximately 80% and a reversible charge capacity of 800 mAhg-1 over 100 cycles at 0.5 Ag-1 with good retention. Through a green and simple procedure, a remarkable Si-MP embedded carbon-matrix with porous structure is established to achieve commercially high performance Si-MP/C composite anodes and also to resolve the issues of waste disposal.

  4. Scientific Opinion on the safety assessment of the “Phoenix - LNOc” process used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2014-06-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the recycling process Phoenix – LNOc process (EU register number RECYC028. The input to the process is hot caustic washed and dried PET flakes originating from collected post-consumer poly(ethylene terephthalate (PET bottles and containing no more than 5 % of PET from non-food consumer applications. In this process, washed and dried flakes are grinded into small particle size powder, and then powder is compacted into pellets which fed into a reactor at high temperature under inert gas flow. Having examined the results of the challenge test provided, the Panel concluded that the three steps, the pulverisation, the compaction and the decontamination are the critical steps that determine the decontamination efficiency of the process. The operating parameters to control the performance of these critical steps are well defined and are particle size for the pulverisation (step 2, time, pressure and pellet size for the compaction (step 3 and temperature, dry air flow and the residence time for the decontamination (step 4. The operating parameters of these steps in the process are at least as severe as those obtained from the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food derived from the exposure scenario for infants and 0.15 μg/kg food derived from the exposure scenario for toddlers. The Panel concluded that the recycled PET obtained from this process is not of safety concern when used to manufacture articles intended for food contact material applications in compliance with the conditions as specified in the conclusion of the opinion.

  5. Recycled Pulsars: Spins, Masses and Ages

    CERN Document Server

    Tauris, Thomas M

    2016-01-01

    Recycled pulsars are mainly characterized by their spin periods, B-fields and masses. All these quantities are affected by previous interactions with a companion star in a binary system. Therefore, we can use these quantities as fossil records and learn about binary evolution. Here, I briefly review the distribution of these observed quantities and summarize our current understanding of the pulsar recycling process.

  6. India's ship recycling trade-off

    NARCIS (Netherlands)

    Worrell, E.; Athanasopoulou, V.

    2014-01-01

    The special nature of India's steel industry lends particular importance to ship recycling as a source of scrap. Ship recycling in upgraded 'green' facilities can substitute other 'dirty' ironmaking processes, resulting in energy savings and air pollutant emission reductions for the Indian steel sec

  7. Research on the suitability of organosolv semi-chemical triticale fibers as reinforcement for recycled HDPE composites

    Directory of Open Access Journals (Sweden)

    Nour-Eddine El Mansouri

    2012-11-01

    Full Text Available The main objective of this research was to study the feasibility of incorporating organosolv semi-chemical triticale fibers as the reinforcing element in recycled high density polyethylene (HDPE. In the first step, triticale fibers were characterized in terms of chemical composition and compared with other biomass species (wheat, rye, softwood, and hardwood. Then, organosolv semi-chemical triticale fibers were prepared by the ethanolamine process. These fibers were characterized in terms of its yield, kappa number, fiber length/diameter ratio, fines, and viscosity; the obtained results were compared with those of eucalypt kraft pulp. In the second step, the prepared fibers were examined as a reinforcing element for recycled HDPE composites. Coupled and non-coupled HDPE composites were prepared and tested for tensile properties. Results showed that with the addition of the coupling agent maleated polyethylene (MAPE, the tensile properties of composites were significantly improved, as compared to non-coupled samples and the plain matrix. Furthermore, the influence of MAPE on the interfacial shear strength (IFSS was studied. The contributions of both fibers and matrix to the composite strength were also studied. This was possible by the use of a numerical iterative method based on the Bowyer-Bader and Kelly-Tyson equations.

  8. Application of Decomposition Methodology to Solve Integrated Process Design and Controller Design Problems for Reactor-Separator-Recycle System

    DEFF Research Database (Denmark)

    Abd.Hamid, Mohd-Kamaruddin; Sin, Gürkan; Gani, Rafiqul

    2010-01-01

    This paper presents the integrated process design and controller design (IPDC) for a reactor-separator-recycle (RSR) system and evaluates a decomposition methodology to solve the IPDC problem. Accordingly, the IPDC problem is solved by decomposing it into four hierarchical stages: (i) pre-analysi...... to the solution of IPDC problems for RSR systems.......This paper presents the integrated process design and controller design (IPDC) for a reactor-separator-recycle (RSR) system and evaluates a decomposition methodology to solve the IPDC problem. Accordingly, the IPDC problem is solved by decomposing it into four hierarchical stages: (i) pre...... the design of a RSR system involving consecutive reactions, A B -> C and shown to provide effective solutions that satisfy design, control and cost criteria. The advantage of the proposed methodology is that it is systematic, makes use of thermodynamic-process knowledge and provides valuable insights...

  9. Sustainable Engineering and Improved Recycling of PET for High-Value Applications: Transforming Linear PET to Lightly Branched PET with a Novel, Scalable Process

    Science.gov (United States)

    Pierre, Cynthia; Torkelson, John

    2009-03-01

    A major challenge for the most effective recycling of poly(ethylene terephthalate) concerns the fact that initial melt processing of PET into a product leads to substantial degradation of molecular weight. Thus, recycled PET has insufficient melt viscosity for reuse in high-value applications such as melt-blowing of PET bottles. Academic and industrial research has tried to remedy this situation by synthesis and use of ``chain extenders'' that can lead to branched PET (with higher melt viscosity than the linear recycled PET) via condensation reactions with functional groups on the PET. Here we show that simple processing of PET via solid-state shear pulverization (SSSP) leads to enhanced PET melt viscosity without need for chemical additives. We hypothesize that this branching results from low levels of chain scission accompanying SSSP, leading to formation of polymeric radicals that participate in chain transfer and combination reactions with other PET chains and thereby to in situ branch formation. The pulverized PET exhibits vastly enhanced crystallization kinetics, eliminating the need to employ cold crystallization to achieve maximum PET crystallinity. Results of SSSP processing of PET will be compared to results obtained with poly(butylene terephthalate).

  10. Análise do desempenho de sistema de controle de processos com reciclo = Performance analysis of the control system of recycle processes

    Directory of Open Access Journals (Sweden)

    Luiz Mário de Matos Jorge

    2008-01-01

    Full Text Available A necessidade de economia de energia, as leis ambientais e a qualidade dos produtos tem exigido processos mais integrados. Uma forma de integração de processos é via reciclo de massa. Neste trabalho, objetivou-se a investigação da influência do reciclo demassa, no desempenho de diferentes estruturas de sistemas de controle e a sua relação com indicadores de controlabilidade e resiliência. Conclui-se que o reciclo e a estrutura influenciam no desempenho do sistema de controle e que esta influência pode ser previstapor indicadores de controlabilidade e resiliência.The need for greater energy savings, stringent environmental laws and product quality have all demanded better process integration. One path for process integration is through the mass recycle process. The objective of this study is to investigate the influence of mass recycle in the performance of different control system structures, and its relation with controllability and resiliency indicators. We conclude that both recycle and structure influence in theperformance of the control system, and this influence can be foreseen by controllability and resiliency indicators.

  11. Scientific Opinion on the safety assessment of the process “Phoenix - ESPS”, used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2014-05-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the recycling process Phoenix – ESPS process (EU register No RECYC035. The input to the process is hot caustic washed and dried poly(ethylene terephthalate (PET flakes originating from collected post-consumer PET containers, mainly bottles and containing no more than 5 % of PET from non-food consumer applications. In this process, washed and dried flakes are ground into small particle size powder, this powder is then fed into a reactor at high temperature under inert gas flow for decontamination. Having examined the results of the challenge test provided, the Panel concluded that the two steps, the pulverisation and the decontamination are the critical steps that determine the decontamination efficiency of the process. The operating parameters to control the performance of these critical steps are particle size for the pulverisation (step 2, temperature, dry air flow and residence time for the decontamination (step 3 and these are well defined. The operating parameters of these steps in the process are at least as severe as those used in the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore the Panel concluded that the recycled PET obtained from this process intended to be used up to 100 % for the manufacture of materials and articles for contact with all types of foodstuffs for long term storage at room temperature, with or without hot-fill is not considered of safety concern.

  12. Recycled High-Density Polyethylene and Rice Husk as a Wetted Pad in Evaporative Cooling System

    Directory of Open Access Journals (Sweden)

    Nitipong Soponpongpipat

    2011-01-01

    Full Text Available Problem statement: The low cost and easy-to-find materials, for being used as wetted pad of evaporative cooling system, are necessary for agriculture. This study, thus, studied the evaporative cooling efficiency and pressure drop of recycled High-Density Polyethylene (HDPE and rice husk as a wetted pad in evaporative cooling system. Approach: The study was done by establishing the tested wetted pad with 25.4 and 50.8 mm of thickness. The velocity air flow through wetted pad was controlled at 1, 2 and 3 m sec−1 respectively. In addition, the dry bulb and wet bulb temperatures of inlet air were controlled at 30.1 ± 1.0°C and 23.2 ± 1.1°C, respectively. The commercial wetted pad was also tested in order to compare results with rice husk and recycled HDPE. Results: It was found that rice husk wetted pad gave the average saturation efficiency of 55.9 %, while HDPE gave the average saturation efficiency of 29.1%. However, the pressure drop across wetted pad of rice husk and recycled HDPE was significantly higher than that of commercial wetted pad. For the effect of air velocity on saturation efficiency and pressure drop, it was found that higher air velocity decreased saturation efficiency and increased pressure drop across wetted pad. Conclusion: Finally, the rice husk has a potential as wetted pad material. However, further study about optimum point between operation cost and materials cost of using rice husk wetted pad is needed.

  13. Recyclable plastics as substrata for settlement and growth of bryozoans Bugula neritina and barnacles Amphibalanus amphitrite.

    Science.gov (United States)

    Li, Heng-Xiang; Orihuela, Beatriz; Zhu, Mei; Rittschof, Daniel

    2016-11-01

    Plastics are common and pervasive anthropogenic debris in marine environments. Floating plastics provide opportunities to alter the abundance, distribution and invasion potential of sessile organisms that colonize them. We selected plastics from seven recycle categories and quantified settlement of (i) bryozoans Bugula neritina (Linnaeus, 1758) in the lab and in the field, and of (ii) barnacles Amphibalanus (= Balanus) amphitrite (Darwin, 1854) in the field. In the laboratory we cultured barnacles on the plastics for 8 weeks and quantified growth, mortality, and breaking strength of the side plates. In the field all recyclable plastics were settlement substrata for bryozoans and barnacles. Settlement depended on the type of plastic. Fewer barnacles settled on plastic surfaces compared to glass. In the lab and in the field, bryozoan settlement was higher on plastics than on glass. In static laboratory rearing, barnacles growing on plastics were initially significantly smaller than on glass. This suggested juvenile barnacles were adversely impacted by materials leaching from the plastics. Barnacle mortality was not significantly different between plastic and glass surfaces, but breaking strength of side plates of barnacles on polyvinyl chloride (PVC) and polycarbonate (PC) were significantly lower than breakage strength on glass. Plastics impact marine ecosystems directly by providing new surfaces for colonization with fouling organisms and by contaminants shown previously to leach out of plastics and impact biological processes.

  14. STUDY ON THE PYROLYSIS AND RECYCLING OF PVC WASTE AS AN ENERGY SOURCE

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    IntroductionIn China, the production of Poly (vinyl chloride)have reached 2 million tons in 1995, accounts forabout 33% of the total plastics market. PVC is themost common chlorinated plastic and accounts forabout half the chlorine in municipal solid waste. Themost obvious possibility of recycling of waste Plasticsas an enelgy source to Obtain fuel oil is pyrolysisl' (4].The Pyrolysis of chlorine containing polymers such asPVC has been studied extensively. Generally thethermal decomPOsition of PVC is a tWo ...

  15. Recycled stellar ejecta as fuel for star formation and implications for the origin of the galaxy mass-metallicity relation

    CERN Document Server

    Segers, Marijke C; Schaye, Joop; Bower, Richard G; Furlong, Michelle; Schaller, Matthieu; Theuns, Tom

    2015-01-01

    We use cosmological, hydrodynamical simulations from the EAGLE and OWLS projects to assess the significance of recycled stellar ejecta as fuel for star formation. The fractional contributions of stellar mass loss to the cosmic star formation rate (SFR) and stellar mass densities increase with time, reaching $35 \\%$ and $19 \\%$, respectively, at $z=0$. The importance of recycling increases steeply with galaxy stellar mass for $M_{\\ast} < 10^{10.5}$ M$_{\\odot}$, and decreases mildly at higher mass. This trend arises from the mass dependence of feedback associated with star formation and AGN, which preferentially suppresses star formation fuelled by recycling. Recycling is more important for satellites than centrals and its contribution decreases with galactocentric radius. The relative contribution of AGB stars increases with time and towards galaxy centers. This is a consequence of the more gradual release of AGB ejecta compared to that of massive stars, and the preferential removal of the latter by outflow...

  16. Usage of Recycled Pet

    Directory of Open Access Journals (Sweden)

    A. Ebru Tayyar

    2010-01-01

    Full Text Available The increasing industrialization, urbanization and the technological development have caused to increase depletion of the natural resources and environmental pollution's problem. Especially, for the countries which have not enough space recycling of the waste eliminating waste on regular basis or decreasing the amount and volume of waste have provided the important advantages. There are lots of studies and projects to develop both protect resources and prevent environmental pollution. PET bottles are commonly used in beverage industry and can be reused after physical and chemical recycling processes. Usage areas of recycled PET have been developed rapidly. Although recycled PET is used in plastic industry, composite industry also provides usage alternatives of recycled PET. Textile is a suitable sector for recycling of some plastics made of polymers too. In this study, the recycling technologies and applications of waste PET bottles have been investigated and scientific works in this area have been summarized.

  17. Scientific Opinion on the safety evaluation of the process “RPET Nosinyec”, used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2012-12-01

    Full Text Available This scientific opinion of the EFSA Panel on food contact materials, enzymes, flavourings and processing aids deals with the safety evaluation of the recycling process RPET Nosinyec, EC register number RECYC082. The input of the process is washed and dried PET flakes originating from collected post-consumer PET bottles containing no more than 5% of PET from non-food consumer applications. Through this process, washed and dried flakes are extruded into pellets, pre-crystallised then pre-crystallised pellets are fed into a reactor at high temperature under vacuum in which they are further crystallised and solid-state polymerised (SSP. After having examined the challenge test provided, the Panel concluded that the two steps, the extrusion and the decontamination in the batch SSP reactor are the critical steps that determine the decontamination efficiency of the process. The operating parameters to control the performance of these critical steps are well defined and are the temperature, the pressure and the residence time both for the extrusion (step 2 and the SSP (step 4. The operating parameters of these steps in the process are at least as severe as those obtained from the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore the Panel concluded that the recycled PET obtained from this process intended for the manufacture of materials and articles for contact with all types of foodstuffs for long term storage at room temperature, with or without hotfill is not considered of safety concern.

  18. Scientific Opinion on the safety evaluation of the process “Cumapol”, used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2013-04-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the recycling process Cumapol, EC register number RECYC085. The input of the process is hot caustic washed and dried PET flakes originating from collected post-consumer PET articles mainly bottles, containing no more than 5 % of PET from non-food consumer applications. Through this process, washed and dried PET flakes are extruded under vacuum and pelletised. The pellets are crystallised and solid state polymerised (SSP in a continuous reactor at high temperature under inert gas flow. After having examined the challenge test provided, the Panel concluded that the three steps, the decontamination in the vented extruder (step 2 the crystallisation and pre-heating (step 3 and the decontamination in a continuous SSP reactor (step 4 are the critical steps for the decontamination efficiency of the process. The operating parameters to control the performance of these critical steps are the temperature, the pressure and the residence time for the extrusion step 2, the temperature, the pressure, the gas flow and the residence time for crystallisation and pre-heating step 3 and the temperature, the gas flow and the residence time for the SSP step 4. The operating parameters of these steps in the process are at least as severe as those obtained from the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore the Panel concluded that the recycled PET obtained from this process intended for the manufacture of materials and articles for contact with all types of foodstuffs for long term storage at room temperature, with or without hotfill is not considered of safety concern.

  19. Scientific Opinion on the safety assessment of the process “APPE supercycle CP” used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2014-04-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the recycling process APPE Supercycle CP (EU register No RECYC066. The input of the process is hot caustic washed and dried PET flakes originating from collected post-consumer PET containers, mainly bottles, containing no more than 5 % of PET from non-food consumer applications. Through this process, washed and dried PET flakes are extruded under vacuum and pelletised (step 2. The pellets are crystallised at high temperature under vacuum (step 3 and further decontaminated in a solid state polymerisation reactor (SSP at high temperature under vacuum. Having examined the challenge test provided, the Panel concluded that the three steps, the extrusion (step 2, the crystallisation (step 3 and the decontamination in the SSP reactor (step 4 are the critical steps for the decontamination efficiency of the process. The operating parameters to control their performance are the temperature, the gas flow, the pressure and the residence time. The operating parameters of these steps in the process are at least as severe as those obtained from the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore the Panel concluded that the recycled PET obtained from this process intended to be used at up to 100 % for the manufacture of materials and articles for contact with all types of foodstuffs for long term storage at room temperature, with or without hotfill is not considered of safety concern.

  20. Scientific Opinion on the safety assessment of the process "APPE Supercycle B" used to recycle PET for use in food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2014-02-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the recycling process APPE Supercycle B (EU register No RECYC065. The input of the process is hot caustic washed and dried PET flakes originating from collected post-consumer PET containers, mainly bottles, containing no more than 5 % of PET from non-food consumer applications. Through this process, washed and dried PET flakes are further dried at high temperature, extruded under vacuum and pelletised. The pellets are crystallised and then solid state polymerised (SSP in a reactor at high temperature under vacuum. Having examined the challenge test provided, the Panel concluded that the two steps, the crystallisation (step 4 and the decontamination in the SSP reactor (step 5 are the critical steps for the decontamination efficiency of the process. The operating parameters to control their performance are the temperature, pressure and residence time. The operating parameters of these steps in the process are at least as severe as those obtained from the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore the Panel concluded that the recycled PET obtained from this process intended to be used at up to 100 % for the manufacture of materials and articles for contact with all types of foodstuffs for long term storage at room temperature, with or without hotfill is not considered of safety concern.

  1. Scientific Opinion on the safety assessment of the process “Aliplast Buhler B” used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2014-02-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the recycling process Aliplast Buhler B (EU register number RECYC044. The input of the process is hot caustic washed and dried PET flakes originating from collected post-consumer PET containers, mainly bottles, containing no more than 5 % of PET from non-food consumer applications. Through this process, washed and dried PET flakes are heated to the decontamination temperature and subsequently are further decontaminated in a continuous countercurrent reactor under high temperature and inert gas flow. Having examined the challenge test provided, the Panel concluded that the third step, the decontamination in continuous countercurrent reactor for solid state polymerisation (SSP is the critical step that determines the decontamination efficiency of the process. The operating parameters to control its performance are the temperature, the inert gas flow and the residence time. The operating parameters of this step in the process are at least as severe as those obtained from the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore, the recycled PET obtained from this process, intended to be used up to 100 % for the manufacture of materials and articles for contact with all types of foodstuffs for long term storage at room temperature, with or without hotfill, is not considered of safety concern.

  2. Scientific Opinion on the safety assessment of the process SOREPET, based on Buhler B technology, used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2014-04-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the recycling process SOREPET (EU register No RECYC072. The input to the process is hot caustic washed and dried PET flakes originating from collected post-consumer PET containers, mainly bottles, containing no more than 5 % PET from non-food consumer applications. In this process, washed and dried PET flakes are heated to the decontamination temperature and subsequently are further decontaminated in a continuous countercurrent reactor under high temperature and inter gas flow. Having examined the challenge test provided, the Panel concluded that the third step, the decontamination in continuous countercurrent reactor for solid state polymerisation (SSP is the critical step that determines the decontamination efficiency of the process. The operating parameters to control its performance are the temperature, the inert gas flow and the residence time. The operating parameters of this step in the process are at least as severe as those obtained from the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below the modelled migration of 0.1 μg/kg food. The Panel concluded that recycled PET obtained from the process, intended to be used up to 100 % for manufacture of materials and articles for contact with all type of foodstuffs for long term storage at room temperature, with or without hot fill, is not considered of safety concern.

  3. Scientific Opinion on the safety evaluation of the process “MOPET ®” used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2013-02-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the recycling process MOPET ®, EC register number RECYC001. The input of the process is hot caustic washed and dried PET flakes originating from collected post-consumer PET articles mainly bottles containing no more than 5 % of PET from non-food consumer applications. Through this process, washed and dried PET flakes are extruded in a twin-screw extruder to amorphous pellets before being crystallised and solid state polymerised in a batch reactor. After having examined the challenge tests provided, the Panel concluded that, although the extrusion (step 2 contributes significantly to the overall decontamination efficiency, the decontamination in the batch SSP reactor (step 3 is the critical step that determine the decontamination efficiency of the process. The operating parameters to control its performance are well defined and are the temperature, the pressure, the residence time and the inert gas flow. The operating parameters of this step in the process are at least as severe as those obtained from the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore the Panel concluded that the recycled PET obtained from this process intended for the manufacture of materials and articles for contact with all types of foodstuffs for long term storage at room temperature, with or without hotfill is not considered of safety concern.

  4. Contribution of image analysis to the definition of explosibility of fine particles resulting from waste recycling process

    Science.gov (United States)

    Gente, V.; La Marca, F.

    2007-09-01

    In waste recycling processes, the development of comminution technologies is one of the main actions to improve the quality of recycled products. This involves a rise in fine particles production, which could have some effects on explosibility properties of materials. This paper reports the results of experiments done to examine the explosibility of the fine particles resulting from waste recycling process. Tests have been conducted for the products derived from milling processes operated in different operative conditions. In particular, the comminution tests have been executed varying the milling temperature by refrigerant agents. The materials utilized in explosibility tests were different typologies of plastics coming from waste products (PET, ABS and PP), characterized by size lower than 1 mm. The results of explosibility tests, carried out by mean of a Hartmann Apparatus, have been compared with the data derived from image analysis procedure aimed to measure the morphological characteristics of particles. For each typology of material, the propensity to explode appears to be correlated not only to particle size, but also to morphological properties, linked to the operative condition of the milling process.

  5. Treatment of wastewater effluents from paper-recycling plants by coagulation process and optimization of treatment conditions with response surface methodology

    Science.gov (United States)

    Birjandi, Noushin; Younesi, Habibollah; Bahramifar, Nader

    2016-11-01

    In the present study, a coagulation process was used to treat paper-recycling wastewater with alum coupled with poly aluminum chloride (PACl) as coagulants. The effect of each four factors, viz. the dosages of alum and PACl, pH and chemical oxygen demand (COD), on the treatment efficiency was investigated. The influence of these four parameters was described using response surface methodology under central composite design. The efficiency of reducing turbidity, COD and the sludge volume index (SVI) were considered the responses. The optimum conditions for high treatment efficiency of paper-recycling wastewater under experimental conditions were reached with numerical optimization of coagulant doses and pH, with 1,550 mg/l alum and 1,314 mg/l PACl and 9.5, respectively, where the values for reduction of 80.02 % in COD, 83.23 % in turbidity, and 140 ml/g in SVI were obtained.

  6. Continuous processing of recombinant proteins: Integration of inclusion body solubilization and refolding using simulated moving bed size exclusion chromatography with buffer recycling.

    Science.gov (United States)

    Wellhoefer, Martin; Sprinzl, Wolfgang; Hahn, Rainer; Jungbauer, Alois

    2013-12-06

    An integrated process which combines continuous inclusion body dissolution with NaOH and continuous matrix-assisted refolding based on closed-loop simulated moving bed size exclusion chromatography was designed and experimentally evaluated at laboratory scale. Inclusion bodies from N(pro) fusion pep6His and N(pro) fusion MCP1 from high cell density fermentation were continuously dissolved with NaOH, filtered and mixed with concentrated refolding buffer prior to refolding by size exclusion chromatography (SEC). This process enabled an isocratic operation of the simulated moving bed (SMB) system with a closed-loop set-up with refolding buffer as the desorbent buffer and buffer recycling by concentrating the raffinate using tangential flow filtration. With this continuous refolding process, we increased the refolding and cleavage yield of both model proteins by 10% compared to batch dilution refolding. Furthermore, more than 99% of the refolding buffer of the raffinate could be recycled which reduced the buffer consumption significantly. Based on the actual refolding data, we compared throughput, productivity, and buffer consumption between two batch dilution refolding processes - one using urea for IB dissolution, the other one using NaOH for IB dissolution - and our continuous refolding process. The higher complexity of the continuous refolding process was rewarded with higher throughput and productivity as well as significantly lower buffer consumption compared to the batch dilution refolding processes.

  7. Study of barrier properties and chemical resistance of recycled PET coated with amorphous carbon through a plasma enhanced chemical vapour deposition (PECVD) process.

    Science.gov (United States)

    Cruz, S A; Zanin, M; Nerin, C; De Moraes, M A B

    2006-01-01

    Many studies have been carried out in order to make bottle-to-bottle recycling feasible. The problem is that residual contaminants in recycled plastic intended for food packaging could be a risk to public health. One option is to use a layer of virgin material, named functional barrier, which prevents the contaminants migration process. This paper shows the feasibility of using polyethylene terephthalate (PET) recycled for food packaging employing a functional barrier made from hydrogen amorphous carbon film deposited by Plasma Enhanced Chemical Vapour Deposition (PECVD) process. PET samples were deliberately contaminated with a series of surrogates using a FDA protocol. After that, PET samples were coated with approximately 600 and 1200 Angstrons thickness of amorphous carbon film. Then, the migration tests using as food simulants: water, 10% ethanol, 3% acetic acid, and isooctane were applied to the sample in order to check the chemical resistance of the new coated material. After the tests, the liquid extracts were analysed using a solid-phase microextraction device (SPME) coupled to GC-MS.

  8. Scientific Opinion on the safety evaluation of the process “PKR”, used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2013-02-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the recycling process PKR, EC register number RECYC009. The input of the PKR is washed and dried PET flakes originating from collected post-consumer PET bottles containing no more than 5 % of PET from non-food consumer applications. Through this process, dried flakes are extruded into pellets which are then pre-crystallised before being fed to a batch solid state polymerization (SSP reactor where high temperature and long residence time are applied under vacuum. After having examined the challenge test provided, the Panel concluded that the decontamination at SSP batch reactor is the critical step that determine the decontamination efficiency of the process. The operating parameters to control the performance of this critical step are well defined and are the temperature, the pressure and the residence time. The operating parameters of this step in the process are at least as severe as those obtained from the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore the Panel concluded that the recycled PET obtained from this process intended for the manufacture of materials and articles for contact with all types of foodstuffs for long term storage at room temperature, with or without hotfill, is not considered of safety concern.

  9. Steady state recycling chromatography with solvent removal-effect of solvent removal constraints on process operation under ideal conditions.

    Science.gov (United States)

    Siitonen, Jani; Sainio, Tuomo

    2014-05-09

    Steady state recycling chromatography (SSR) offers a means to reduce eluent consumption and increase productivity in preparative and production scale chromatographic separations. Even better performance is obtained with an integrated process by coupling solvent removal unit to the chromatographic separation unit. Here a design method for SSR with an integrated solvent removal unit (SSR-SR) is presented. The method is more practical than previous work as the effect of physical constraints, such as solubility or viscosity, imposed on the amount of solvent removed is included. The method holds under ideal conditions for binary systems with competitive Langmuir isotherm model. The design equations allow calculation of the regions of feasible operating parameters when either the maximum concentrations in the solvent removal unit or of the solution fed into the chromatographic column is restricted. The method was applied to analyze the performance of different SSR-SR configurations in two case studies: the separation of mandelic acid enantiomers and the separation of EMD 53986 enantiomers. The benefits of SSR-SR are relatively small under ideal conditions but the design method developed here can give a good starting point for designing SSR-SR processes under non-ideal conditions.

  10. Chemical and biological effects of heavy distillate recycle in the SRC-II process

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, B.W.; Pelroy, R.A.; Anderson, R.P.; Freel, J.

    1983-12-01

    Recent work from the Merriam Laboratory continuous coal liquefaction units shows that heavy distillate from the SRC-II process can be recycled to extinction, and hence a distillate product boiling entirely below 310/sup 0/C (590/sup 0/F) (or other selected boiling points) is feasible. In these runs distillate yield was not reduced; gas make was unaffected; and hydrogen consumption was increased only slightly, in keeping with the generally higher hydrogen content of lighter end products. Total distillate yield (C/sub 5/-590/sup 0/F) was 56 wt %, MAF coal in runs with subbituminous coal from the Amax Belle Ayr mine. Product endpoint is well below 371/sup 0/C (700/sup 0/F), the temperature above which coal distillates appear to become genotoxic; and the product was shown to be free of mutagenic activity in the Ames test. Chemical analyses showed both the < 270/sup 0/C (< 518/sup 0/F) and the < 310/sup 0/C (< 590/sup 0/F) distillates to be essentially devoid of several reference polycyclic compounds known to be carcinogenic in laboratory animals. Tests for tumorigenic or carcinogenic activity were not carried out on these materials. However, a comparison of chemical data from the Merriam heavy distillate samples with data on the other SRC-II distillates where carcinogenesis or tumorigenesis data is available leads to the expectation that < 371/sup 0/C (< 700/sup 0/F) materials from the Merriam Laboratory will have greatly reduced tumorigenic and carcinogenic activity in skin painting tests. Other studies suggest the product should be more readily upgraded than full-range (C/sub 5/-900/sup 0/F) distillate.

  11. Pyrolysis and catalytic pyrolysis as a recycling method of waste CDs originating from polycarbonate and HIPS.

    Science.gov (United States)

    Antonakou, E V; Kalogiannis, K G; Stephanidis, S D; Triantafyllidis, K S; Lappas, A A; Achilias, D S

    2014-12-01

    Pyrolysis appears to be a promising recycling process since it could convert the disposed polymers to hydrocarbon based fuels or various useful chemicals. In the current study, two model polymers found in WEEEs, namely polycarbonate (PC) and high impact polystyrene (HIPS) and their counterparts found in waste commercial Compact Discs (CDs) were pyrolysed in a bench scale reactor. Both, thermal pyrolysis and pyrolysis in the presence of two catalytic materials (basic MgO and acidic ZSM-5 zeolite) was performed for all four types of polymers. Results have shown significant recovery of the monomers and valuable chemicals (phenols in the case of PC and aromatic hydrocarbons in the case of HIPS), while catalysts seem to decrease the selectivity towards the monomers and enhance the selectivity towards other desirable compounds.

  12. Recycling of Vineyard and Winery Wastes as Nutritive Composts for Edible Mushroom Cultivation

    Science.gov (United States)

    Petre, Marian; Teodorescu, Alexandru

    2011-01-01

    Every year, in Romania huge amounts of wine and vine wastes cause serious environmental damages in vineyards as well as nearby winery factories, for instance, by their burning on the soil surface or their incorporation inside soil matrix. The optimal and efficient way to solve these problems is to recycle these biomass wastes as main ingredients in nutritive composts preparation that could be used for edible mushrooms cultivation. In this respect, the main aim of this work was to establish the best biotechnology of winery and vine wastes recycling by using them as appropriate growth substrata for edible and medicinal mushrooms. According to this purpose, two mushroom species of Basidiomycetes, namely Lentinula edodes as well as Pleurotus ostreatus were used as pure mushroom cultures in experiments. The experiments of inoculum preparation were set up under the following conditions: constant temperature, 23° C; agitation speed, 90-120 rev min-1 pH level, 5.0-6.0. All mycelia mushroom cultures were incubated for 120-168 h. In the next stage of experiments, the culture composts for mushroom growing were prepared from the lignocellulose wastes as vine cuttings and marc of grapes in order to be used as substrata in mycelia development and fruit body formation. The tested culture variants were monitored continuously to keep constant the temperature during the incubation as well as air humidity, air pressure and a balanced ratio of the molecular oxygen and carbon dioxide. In every mushroom culture cycle all the physical and chemical parameters that could influence the mycelia growing as well as fruit body formation of L. edodes and P. ostreatus were compared to the same fungal cultures that were grown on poplar logs used as control samples.

  13. Functional elastic hydrogel as recyclable membrane for the adsorption and degradation of methylene blue.

    Science.gov (United States)

    Bao, Song; Wu, Dongbei; Wang, Qigang; Su, Teng

    2014-01-01

    Developing the application of high-strength hydrogels has gained much attention in the fields of medical, pharmacy, and pollutant removal due to their versatility and stimulus-responsive properties. In this presentation, a high-strength freestanding elastic hydrogel membrane was constructed by clay nanosheets, N, N-dimethylacrylamide and 2-acrylamide-2-methylpropanesulfonic acid for adsorption of methylene blue and heavy metal ions. The maximum values of elongation and Young's modulus for 0.5% AMPSNa hydrogel were 1901% and 949.4 kPa, respectively, much higher than those of traditional hydrogels. The adsorptions were confirmed to follow pseudo-second kinetic equation and Langmuir isotherm model fits the data well. The maximum adsorption capacity of hydrogel towards methylene blue was 434.8 mg g(-1). The hydrogel also exhibited higher separation selectivity to Pb(2+) than Cu(2+). The methylene blue adsorbed onto the hydrogel membrane can be photocatalytically degraded by Fenton agent and the hydrogel membrane could be recycled at least five times without obvious loss in mechanical properties. In conclusion, this presentation demonstrates a convenient strategy to prepare tough and elastic clay nanocomposite hydrogel, which can not only be applied as recyclable membrane for the photocatalytic degradation of organic dye, but also for the recovery of valuables.

  14. Functional elastic hydrogel as recyclable membrane for the adsorption and degradation of methylene blue.

    Directory of Open Access Journals (Sweden)

    Song Bao

    Full Text Available Developing the application of high-strength hydrogels has gained much attention in the fields of medical, pharmacy, and pollutant removal due to their versatility and stimulus-responsive properties. In this presentation, a high-strength freestanding elastic hydrogel membrane was constructed by clay nanosheets, N, N-dimethylacrylamide and 2-acrylamide-2-methylpropanesulfonic acid for adsorption of methylene blue and heavy metal ions. The maximum values of elongation and Young's modulus for 0.5% AMPSNa hydrogel were 1901% and 949.4 kPa, respectively, much higher than those of traditional hydrogels. The adsorptions were confirmed to follow pseudo-second kinetic equation and Langmuir isotherm model fits the data well. The maximum adsorption capacity of hydrogel towards methylene blue was 434.8 mg g(-1. The hydrogel also exhibited higher separation selectivity to Pb(2+ than Cu(2+. The methylene blue adsorbed onto the hydrogel membrane can be photocatalytically degraded by Fenton agent and the hydrogel membrane could be recycled at least five times without obvious loss in mechanical properties. In conclusion, this presentation demonstrates a convenient strategy to prepare tough and elastic clay nanocomposite hydrogel, which can not only be applied as recyclable membrane for the photocatalytic degradation of organic dye, but also for the recovery of valuables.

  15. Laser-induced breakdown spectroscopy application to control of the process of precious metal recovery and recycling

    Energy Technology Data Exchange (ETDEWEB)

    Legnaioli, S.; Lorenzetti, G.; Pardini, L. [Institute of Chemistry of Organometallic Compounds, Research Area of CNR, Via G. Moruzzi, 1-56124 Pisa (Italy); Palleschi, V., E-mail: vincenzo.palleschi@cnr.it [Institute of Chemistry of Organometallic Compounds, Research Area of CNR, Via G. Moruzzi, 1-56124 Pisa (Italy); Pace, D.M. Diaz [Instituto de Fisica ' Arroyo Seco' , Facultad de Ciencias Exactas, Paraje Arroyo Seco-(B7000GHG) Tandil (Argentina); Garcia, F. Anabitarte [Photonic Engineering Group, Universidad de Cantabria, Edificio I-D-i Telecomunicacion, Dpto. TEISA-39005 Santander (Spain); Grassi, R.; Sorrentino, F.; Carelli, G.; Francesconi, M.; Francesconi, F. [Marwan Technology, Largo Pontecorvo, 3-56127 Pisa Italy (Italy); Borgogni, R. [CABRO S.p.A.,Via Setteponti, 141-52100 Arezzo (Italy)

    2012-05-15

    In this paper, we discuss the application of laser-induced breakdown spectroscopy to precious metal alloys used for the control of the process of recovery and recycling of scraps and waste of industrial processes. In particular, the possibility to obtain sensitivity and trueness comparable to the current systems used in industrial environment in the quantitative determination of the elements of interest was explored. The present study demonstrates that laser-induced breakdown spectroscopy can be considered as a viable alternative to inductively coupled plasma optical emission spectrometry and X-ray fluorescence spectroscopy for the determination of recovered precious metals. The limits of detection obtained are of the order of 0.2 mg/g for all the elements considered. The maximum deviation with respect to the nominal concentrations is around 1 mg/g at concentrations around 20 mg/g (gold) corresponding to a relative error slightly higher than {+-} 5%. - Highlights: Black-Right-Pointing-Pointer We discuss application of LIBS for the analysis of recovered precious metals. Black-Right-Pointing-Pointer The advantages and drawbacks of LIBS vs. XRF are evidenced. Black-Right-Pointing-Pointer A strategy is devised for obtaining by LIBS limits of detection comparable to XRF. Black-Right-Pointing-Pointer The same strategy would provide trueness in analytical results comparable to XRF. Black-Right-Pointing-Pointer The time needed and the complexity of LIBS analysis would not exceed the XRF ones.

  16. Effect of acetic acid in recycling water on ethanol production for cassava in an integrated ethanol-methane fermentation process.

    Science.gov (United States)

    Yang, Xinchao; Wang, Ke; Zhang, Jianhua; Tang, Lei; Mao, Zhonggui

    2016-11-01

    Recently, the integrated ethanol-methane fermentation process has been studied to prevent wastewater pollution. However, when the anaerobic digestion reaction runs poorly, acetic acid will accumulate in the recycling water. In this paper, we studied the effect of low concentration of acetic acid (≤25 mM) on ethanol fermentation at different initial pH values (4.2, 5.2 or 6.2). At an initial pH of 4.2, ethanol yields increased by 3.0% and glycerol yields decreased by 33.6% as the acetic acid concentration was increased from 0 to 25 mM. Raising the concentration of acetic acid to 25 mM increased the buffering capacity of the medium without obvious effects on biomass production in the cassava medium. Acetic acid was metabolized by Saccharomyces cerevisiae for the reason that the final concentration of acetic acid was 38.17% lower than initial concentration at pH 5.2 when 25 mM acetic acid was added. These results confirmed that a low concentration of acetic acid in the process stimulated ethanol fermentation. Thus, reducing the acetic acid concentration to a controlled low level is more advantageous than completely removing it.

  17. Thermal recycling of plastic waste using pyrolysis-gasification process for energy production

    Energy Technology Data Exchange (ETDEWEB)

    Forbit, George Teke

    2012-04-04

    waste management organisations and disposal sites were conducted in various cities in the three case study countries. A resource-oriented manual sorting using the resource-recovery scavenging approach (RESA) simulating integration of scavenger's activities in waste sorting was conducted at BTU and Lagos. Major results obtained include: Characterization, quantification and classification of a dry sample of commingled MSW at Cottbus gave major waste fractions in order of decreasing abundance as 23.15% of residue waste, 19.75% of paper and cardboards, 17.80% of plastics, 14.63% of textiles and diapers, 10.06% of food waste and 9.55% of glass. An overall 33.21% of waste sample is compostable for manure, 52.2% usable as feedstock in the PG technology and 99.81% of total sample having a material or energy recovery potential. In Lagos, Nigeria main fractions were 29% of plastics, 36% of residue waste, 17% of soil/sand, 7% of paper with overall 41% usable as feedstock in PG technology, 39% compostable, 3% of recyclable (metal and glass). Sand can be recovered from the soil/sand fraction for construction. Excluding the sand/soil mixture, 83% of the total waste sample has potential for material and energy value. An appropriate technology that applies principles of pyrolysis and gasification to convert non-PVC plastic waste to energy was designed, constructed, tested and optimized with respect to: (i) Successful functioning with conversion of averagely 98.51% of input constituting of 82.78-98.21% of charcoal and 96.72-99.27% of plastic to heat energy (ii) Evaluation of socioeconomic and environmental impacts based on pyrolysis and exhaust gas and ash residue analysis showed absence of VOCs, heavy metals and pollutant organic and inorganic compounds; (iii) Safety and risk assessment to indoor pollution is very low; (iv) Assessment of the WTA and WTP indicated that 94% of respondents in Lagos, Nigeria and Porto Novo, Benin were willing to accept and pay for this technology

  18. Membrane process treatment for greywater recycling: investigations on direct tubular nanofiltration.

    Science.gov (United States)

    Hourlier, F; Massé, A; Jaouen, P; Lakel, A; Gérente, C; Faur, C; Cloirec, P Le

    2010-01-01

    On-site greywater recycling and reuse is one of the main ways to reduce potable water requirement in urban areas. Direct membrane filtration is a promising technology to recycle greywater on-site. This study aimed at selecting a tubular nanofiltration (NF) membrane and its operating conditions in order to treat and reuse greywater in buildings. To do so, a synthetic greywater (SGW) was reconstituted in order to conduct experiments on a reproducible effluent. Then, three PCI NF membranes (AFC30, AFC40 and AFC80) having distinct molecular weight cut-offs were tested to recycle this SGW with a constant concentration at 25°C at two different transmembrane pressures (20 and 35 bar). The best results were obtained with AFC80 at 35 bar: the flux was close to 50 L m⁻²  h⁻¹, retentions of 95% for chemical oxygen demand and anionic surfactants were observed, and no Enterococcus were detected in the permeate. The performances of AFC80 were also evaluated on a real greywater: fluxes and retentions were similar to those observed on SGW. These results demonstrate the effectiveness of direct nanofiltration to recycle and reuse greywater.

  19. Discovery as a process

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C.

    1994-05-01

    The three great myths, which form a sort of triumvirate of misunderstanding, are the Eureka! myth, the hypothesis myth, and the measurement myth. These myths are prevalent among scientists as well as among observers of science. The Eureka! myth asserts that discovery occurs as a flash of insight, and as such is not subject to investigation. This leads to the perception that discovery or deriving a hypothesis is a moment or event rather than a process. Events are singular and not subject to description. The hypothesis myth asserts that proper science is motivated by testing hypotheses, and that if something is not experimentally testable then it is not scientific. This myth leads to absurd posturing by some workers conducting empirical descriptive studies, who dress up their study with a ``hypothesis`` to obtain funding or get it published. Methods papers are often rejected because they do not address a specific scientific problem. The fact is that many of the great breakthroughs in silence involve methods and not hypotheses or arise from largely descriptive studies. Those captured by this myth also try to block funding for those developing methods. The third myth is the measurement myth, which holds that determining what to measure is straightforward, so one doesn`t need a lot of introspection to do science. As one ecologist put it to me ``Don`t give me any of that philosophy junk, just let me out in the field. I know what to measure.`` These myths lead to difficulties for scientists who must face peer review to obtain funding and to get published. These myths also inhibit the study of science as a process. Finally, these myths inhibit creativity and suppress innovation. In this paper I first explore these myths in more detail and then propose a new model of discovery that opens the supposedly miraculous process of discovery to doser scrutiny.

  20. Progress towards a process for the recycling of nickel metal hydride electric cells using a deep eutectic solvent

    Directory of Open Access Journals (Sweden)

    Mark R.StJ. Foreman

    2016-12-01

    Full Text Available Solvent extraction experiments relating to the recycling of the transition metals and lanthanides in nickel metal hydride cells are presented. The metal extraction is occurring from a deep eutectic solvent which is formed from chemicals suitable for use in food and related products. While it has been shown that the water content of the DES has a large effect on the extraction of transition metals by a mixture of chloride ionic liquid (Aliquat 336 and an aromatic solvent, the water content has a smaller effect on the solvent extraction of lanthanides with a solution of di(2-ethylhexyl hydrogen phosphate (DEHPA in a saturated aliphatic hydrocarbon. This study suggests that an industrial scale solvent extraction process for the recycling of metals from nickel hydride electrical cells will be feasible.

  1. Recycle Glass in Foam Glass Production

    DEFF Research Database (Denmark)

    Petersen, Rasmus Rosenlund; König, Jakob; Yue, Yuanzheng

    The foam glass industry turn recycle glass into heat insulating building materials. The foaming process is relative insensitive to impurities in the recycle glass. It is therefore considered to play an important role in future glass recycling. We show and discuss trends of use of recycled glasses...... in foam glass industry and the supply sources and capacity of recycle glass....

  2. Integral Politics as Process

    Directory of Open Access Journals (Sweden)

    Tom Atlee

    2010-03-01

    Full Text Available Using the definition proposed here, integral politics can be a process of integrating diverse perspectives into wholesome guidance for a community or society. Characteristics that follow from this definition have ramifications for understanding what such political processes involve. Politics becomes integral as it transcends partisan battle and nurtures generative conversation toward the common good. Problems, conflicts and crises become opportunities for new (or renewed social coherence. Conversational methodologies abound that can help citizen awareness temporarily expand during policy-making, thus helping raise society’s manifested developmental stage. Convening archetypal stakeholders or randomly selected citizens in conversations designed to engage the broader public enhances democratic legitimacy. With minimal issue- and candidate-advocacy, integral political leaders would develop society’s capacity to use integral conversational tools to improve its health, resilience, and collective intelligence. This both furthers and manifests evolution becoming conscious of itself.

  3. Functions as proofs as processes

    CERN Document Server

    Beffara, Emmanuel

    2011-01-01

    This paper presents a logical approach to the translation of functional calculi into concurrent process calculi. The starting point is a type system for the {\\pi}-calculus closely related to linear logic. Decompositions of intuitionistic and classical logics into this system provide type-preserving translations of the \\lambda- and \\lambda\\mu-calculus, both for call-by-name and call-by-value evaluation strategies. Previously known encodings of the \\lam-calculus are shown to correspond to particular cases of this logical embedding. The realisability interpretation of types in the \\pi-calculus provides systematic soundness arguments for these translations and allows for the definition of type-safe extensions of functional calculi.

  4. Recycling of demolished concrete

    Energy Technology Data Exchange (ETDEWEB)

    Nagataki, S. [Niigata Univ., Niigata (Japan). Dept. of Civil Engineering; Iida, K. [Technology Centre of Taisei Corp., Yokohama (Japan)

    2001-07-01

    There is a significant amount of research being conducted in Japan on ways to recycle demolished concrete. The material is already being used for road bases and foundations, but in the future, the concrete will have to be recycled as concrete aggregate. Recycling may also include the cement in the concrete in order to address the issue of global warming and carbon dioxide reductions. This initiative is in response to predictions that in the future there will be tremendous quantities of demolished concrete to deal with. Recycling of cement is also necessary in terms of resolving environmental problems and promoting sustainable development. The properties of concrete made with recycled aggregates were described and were compared with original concrete made of known materials. The paper also proposed an approach that should be taken to recycling concrete in the twenty-first century in which reduced limestone was used to reclaim cement. Recycled concrete with cement requires more energy, but uses less resources and discharges less carbon dioxide. Currently, recycled aggregate does not meet the Japanese Industrial Standard for concrete aggregate. The resistance to freeze/thaw cycles was not adequate. The amount of mortar adhered to the recycled aggregate had little affect on the strength and durability of recycled concrete. It was concluded that the quality of recycled concrete aggregate depends on the quality of original concrete. 11 refs., 12 tabs., 11 figs.

  5. Influence of RFID tags on recyclability of plastic packaging.

    Science.gov (United States)

    Aliaga, César; Ferreira, Beatriz; Hortal, Mercedes; Pancorbo, María Ángeles; López, José Manuel; Navas, Francisco Javier

    2011-06-01

    The use of Radio Frequency IDentification Technology (RFID) in the packaging sector is an important logistical improvement regarding the advantages offered by this technology in comparison with barcodes. Nevertheless, the presence of these devices in plastic packaging, and consequently in plastic waste, can cause several problems in the recycling plants due to the materials included in these devices. In this study, the mentioned recycling constraints have been experimentally identified in a pilot scale recycling study consisting in three recycling tests with an increasing presence of RFID tags. Differences in each test were evaluated. Furthermore, the quality of the recycled material of each test was studied through the injection and testing of tests probes. The results of the pilot scale recycling tests did not show a decrease in the quality of the recycled plastic due to the presence of RFID tags. Nevertheless, several operational problems during the recycling process were observed such as the obstruction of the screens, which lessened the process yield and created process interruptions, as well as the loss of extruded plastic during the process. These recycling constraints cannot be directly extrapolated to the industrial plants due to the different working scales. Nevertheless, technological solutions are proposed in order to avoid these recycling constraints if they appear.

  6. Continuous processing of recombinant proteins: integration of refolding and purification using simulated moving bed size-exclusion chromatography with buffer recycling.

    Science.gov (United States)

    Wellhoefer, Martin; Sprinzl, Wolfgang; Hahn, Rainer; Jungbauer, Alois

    2014-04-11

    Continuous processing of recombinant proteins was accomplished by combining continuous matrix-assisted refolding and purification by tandem simulated moving bed (SMB) size-exclusion chromatography (SEC). Recombinant proteins, N(pro) fusion proteins from inclusion bodies were dissolved with NaOH and refolded in the SMB system with a closed-loop set-up with refolding buffer as the desorbent buffer and buffer recycling of the refolding buffer of the raffinate by tangential flow filtration. For further purification of the refolded proteins, a second SMB operation also based on SEC was added. The whole system could be operated isocratically with refolding buffer as the desorbent buffer, and buffer recycling could also be applied in the purification step. Thus, a significant reduction in buffer consumption was achieved. The system was evaluated with two proteins, the N(pro) fusion pep6His and N(pro) fusion MCP-1. Refolding solution, which contained residual N(pro) fusion peptide, the cleaved autoprotease N(pro), and the cleaved target peptide was used as feed solution. Full separation of the cleaved target peptide from residual proteins was achieved at a purity and recovery in the raffinate and extract, respectively, of approximately 100%. In addition, more than 99% of the refolding buffer of the raffinate was recycled. A comparison of throughput, productivity, and buffer consumption of the integrated continuous process with two batch processes demonstrated that up to 60-fold higher throughput, up to 180-fold higher productivity, and at least 28-fold lower buffer consumption can be obtained by the integrated continuous process, which compensates for the higher complexity.

  7. Evaluation of sub-critical water as an extraction fluid for model contaminants from recycled PET for reuse as food packaging material.

    Science.gov (United States)

    Santos, Amélia S F; Agnelli, José A M; Manrich, Sati

    2010-04-01

    Recycling of plastics for food-contact packaging is an important issue and research into meaningful and cost-effective solutions is in progress. In this paper, the use of sub-critical water was evaluated as an alternative way of purifying poly(ethylene terephthalate) (PET) flakes for direct food contact applications. The effects of temperature, pressure and flow rate were assessed on the extraction efficiency of two of the most challenging classes of contaminants (toluene and benzophenone) from PET by sub-critical water using a first-order fractional experimental design. Extraction yield was quantified using GC/FID. The most important parameter was flow rate, indicating that the decrease in sub-critical water polarity with temperature was insufficient to eliminate partition effects. Temperature was also important, but only for the optimization of toluene extraction. These results may be explained by the poor solubility of higher molar mass compounds in sub-critical water compared to lower molar mass compounds under the same conditions, and the small decrease in dielectric constant with temperature under the experimental conditions evaluated. As cleaning efficiency is low and PET is very susceptible to hydrolysis, which limits the use of higher temperatures vis-à-vis physical recycling, the proposed extraction is unsuitable for a standalone super-clean process but may be a step in the process.

  8. Sustainability of bioethanol production from wheat with recycled residues as evaluated by Emergy assessment

    DEFF Research Database (Denmark)

    Coppola, F.; Bastianoni, S.; Østergård, Hanne

    2009-01-01

    An Emergy assessment study of 24 bioethanol production scenarios was carried out for the comparison of bioethanol production using winter wheat grains and/or straw as feedstock and conversion technologies based on starch (1st generation) and/or lignocellulose (2nd generation). An integrated biomass......, were considered. Material and energy flows were assessed to evaluate the bioethanol yield, the production efficiency in terms of Emergy used compared to energy produced (transformity), and the environmental load (ELR) in terms of use of non-renewable resources. These three indicators varied among...... the four feedstock production scenarios to the same extent as among the three different industrial production scenarios and in each case the efficiency was lower and the use of non-renewables higher for the non-recycling system. The system most efficient for production of bioethanol (lowest transformity...

  9. Review of processes for the release of DOE real and non-real property for reuse and recycle

    Energy Technology Data Exchange (ETDEWEB)

    Ranek, N.L.; Kamboj, S.; Hensley, J.; Chen, S.Y.; Blunt, D.

    1997-11-01

    This report summarizes the underlying historical and regulatory framework supporting the concept of authorizing release for restricted or unrestricted reuse or recycle of real and non-real U.S. Department of Energy (DOE) properties containing residual radioactive material. Basic radiation protection principles as recommended by the International Commission on Radiological Protection are reviewed, and international initiatives to investigate radiological clearance criteria are reported. Applicable requirements of the U.S. Nuclear Regulatory Commission, the Environmental Protection Agency, DOE, and the State of Washington are discussed. Several processes that have been developed for establishing cleanup and release criteria for real and non-real DOE property containing residual radioactive material are presented. Examples of DOE real property for which radiological cleanup criteria were established to support unrestricted release are provided. Properties discussed include Formerly Utilized Sites Remedial Action Project sites, Uranium Mill Tailings Remedial Action Project sites, the Shippingport decommissioning project, the south-middle and south-east vaults in the 317 area at Argonne National Laboratory, the Heavy Water Components Test Reactor at DOE`s Savannah River Site, the Experimental Boiling Water Reactor at Argonne National Laboratory, and the Weldon Spring site. Some examples of non-real property for which DOE sites have established criteria to support unrestricted release are also furnished. 10 figs., 4 tabs.

  10. DWPF Recycle Evaporator Simulant Tests

    Energy Technology Data Exchange (ETDEWEB)

    Stone, M

    2005-04-05

    Testing was performed to determine the feasibility and processing characteristics of an evaporation process to reduce the volume of the recycle stream from the Defense Waste Processing Facility (DWPF). The concentrated recycle would be returned to DWPF while the overhead condensate would be transferred to the Effluent Treatment Plant. Various blends of evaporator feed were tested using simulants developed from characterization of actual recycle streams from DWPF and input from DWPF-Engineering. The simulated feed was evaporated in laboratory scale apparatus to target a 30X volume reduction. Condensate and concentrate samples from each run were analyzed and the process characteristics (foaming, scaling, etc) were visually monitored during each run. The following conclusions were made from the testing: Concentration of the ''typical'' recycle stream in DWPF by 30X was feasible. The addition of DWTT recycle streams to the typical recycle stream raises the solids content of the evaporator feed considerably and lowers the amount of concentration that can be achieved. Foaming was noted during all evaporation tests and must be addressed prior to operation of the full-scale evaporator. Tests were conducted that identified Dow Corning 2210 as an antifoam candidate that warrants further evaluation. The condensate has the potential to exceed the ETP WAC for mercury, silicon, and TOC. Controlling the amount of equipment decontamination recycle in the evaporator blend would help meet the TOC limits. The evaporator condensate will be saturated with mercury and elemental mercury will collect in the evaporator condensate collection vessel. No scaling on heating surfaces was noted during the tests, but splatter onto the walls of the evaporation vessels led to a buildup of solids. These solids were difficult to remove with 2M nitric acid. Precipitation of solids was not noted during the testing. Some of the aluminum present in the recycle streams was converted

  11. Development of a correlaton between slurry oil composition and process performance: analyses of slurry recycle oils from H-Coal PDU runs 5, 8 and 9. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Burke, F.P.; Winschel, R.A.; Pochapsky, T.C.

    1981-01-01

    Daily samples of slurry recycle oils from three thirty-day H-Coal PDU runs (5, 8 and 9) were analyzed by /sup 1/H-NMR, GC/MS and various liquid chromatographic techniques. These data were interpreted in light of process performance to investigate the relationship between recycle oil composition and process performance. The data were also used to determine the approach of each PDU run to steady state operation. The results show that the composition of the non-distillate recycle components (resid) is much more sensitive to space velocity than the recycle distillate composition. At high space velocity the low recycle resid quality may be a significant factor, contributing to operability problems and rapid catalyst deactivation. Recycle composition depends more on space velocity than feed coal when comparing operations with Illinois 6 and Kentucky 11 coals. The recycle distillates in H-Coal operation are good hydrogen donors relative to, for example, SRC-I distillates. However, catalyst deactivation with respect to distillate composition appears to proceed at a slower pace than deactivation with respect to resid composition. This suggests that steady state performance may not have been achieved in these 30-day PDU runs, even though gross product distributions were at apparent steady state.

  12. The selective recycling of mixed plastic waste of polylactic acid and polyethylene terephthalate by control of process conditions

    OpenAIRE

    Carné Sánchez , Arnau; Collinson, Simon R.

    2011-01-01

    The glycolysis of postconsumer polyethylene terephthalate (PET) waste was evaluated with catalysts of zinc acetate, zinc stearate and zinc sulfate, showing that zinc acetate was the most soluble and effective. The chemical recycling by solvolysis of polylactic acid (PLA) and PET waste in either methanol or ethanol was investigated. Zinc acetate as a catalyst was found to be necessary to yield an effective depolymerization of waste PLA giving lactate esters, while with the same reaction condit...

  13. Exploring metal recycling business in China

    Energy Technology Data Exchange (ETDEWEB)

    Soga, K. [DOWA Environmental Management Co., Ltd., Suzhou, Jiangsu (China)

    2007-07-01

    Recycling activities related to the copper smelting process in China were discussed. Although China is a key player in terms of resource circulation in the world, the lack of proper recycling capabilities has hindered the growth of a recycling industry in China. A recycling network established by DOWA Environmental Management was established by contracting with Chinese smelters and refineries. This paper also provided details of recent recycling initiatives, metal scrap processes, industrial waste treatment processes, and soil remediation programs recently initiated in the country. The study concluded by suggesting that the trade of recycling materials must not remain one-sided between China and other developed countries. The high demand for natural resources in Brazil, Russia, India and China can be used as an incentive to increase recycling processes on a wider scale. A pilot project is now being planned by DOWA to establish an international network to collect and transfer used cellular phones to Japan for resource recovery. The company will research and evaluate feasible collection schemes for each participating country. The project may be expanded to include other products. 3 tabs., 5 figs.

  14. Organic-Inorganic Hybrid Silica Material Derived from a Monosilylated Grubbs-Hoveyda Ruthenium Carbene as a Recyclable Metathesis Catalyst

    Directory of Open Access Journals (Sweden)

    Michel Wong Chi Man

    2010-08-01

    Full Text Available The synthesis of a monosilylated Grubbs-Hoveyda ruthenium alkylidene complex is described, as well as the preparation and characterization of the corresponding material by sol-gel cogelification with tetraethoxysilane (TEOS and the assay of this recyclable supported catalyst in ring-closing diene and enyne metathesis reactions under thermal and microwave conditions.

  15. USE OF GAC TECHNOLOGY AND TWO STAGE ION EXCHANGE TECHNIQUE FOR RECYCLING OF WASTEWATER IN TEXTILE WET PROCESSING

    Directory of Open Access Journals (Sweden)

    PROF. MAHESH B. CHOUGULE

    2012-01-01

    Full Text Available Water is essential natural resource for sustaining life and environment, which is always thought to be available in abundance and free gift of nature. Textile industries are one of the major consumers of water and disposing large volumes of effluent to the environment. The textile industry utilizes abundant water in dyeing and finishing processes. There is need to adopt economical practices for the use of water in textile industries. It has been estimated that 3.5 % of the total cost of running the industry is required for water utilization in textile industry. In India textile units are developed all over the country in the form of small industrial estates. Textiles are manufactured to perform a multitude of functions. They are produced to a range of specifications using avariety of fibers, resulting in a complex waste or effluent. Textile waste occurs in a variety of forms throughout production process. The surface water sources are limited and availability of water from them vary from year to year depending upon monsoon conditions. The underground water resources are also getting depleted with theincreasing amount of water drawn from them every year without adequate replenishments. Therefore, the cost of water is rising steeply and the textile mills, which need a large quantity of water, have started taking measures to conserve and recycling. This paper focuses on recycling of wastewater in textile wet processing with experimental analysis of GAC technology and two-stage ion exchange technology.

  16. Recycling potential of air pollution control residue from sewage sludge thermal treatment as artificial lightweight aggregates.

    Science.gov (United States)

    Bialowiec, Andrzej; Janczukowicz, Wojciech; Gusiatin, Zygmunt M; Thornton, Arthur; Rodziewicz, Joanna; Zielinska, Magdalena

    2014-03-01

    Thermal treatment of sewage sludge produces fly ash, also known as the air pollution control residue (APCR), which may be recycled as a component of artificial lightweight aggregates (ALWA). Properties of APCR are typical: high content of Ca, Mg, P2O5, as well as potential to induce alkaline reactions. These properties indicate that ALWA prepared with a high content of APCR may remove heavy metals, phosphorus, and ammonium nitrogen from wastewater with high efficiency. The aim of this preliminary study was to determine the optimal composition of ALWA for potential use as a filter media in wastewater treatment systems. Five kinds of ALWA were produced, with different proportions of ash (shown as percentages in subscripts) in mixture with bentonite: ALWA0 (reference), ALWA12.5, ALWA25, ALWA50, and ALWA100. The following parameters of ALWA were determined: density, bulk density, compressive strength, hydraulic conductivity, and removal efficiency of ions Zn(2+), NH4 (+), and PO4 (3-). Tests showed that ALWA had good mechanical and hydraulic properties, and might be used in wastewater filtering systems. Phosphates and zinc ions were removed with high efficiency (80-96%) by ALWA25-100 in static (batch) conditions. The efficiency of ammonium nitrogen removal was low, <18%. Artificial wastewater treatment performance in dynamic conditions (through-flow), showed increasing removal efficiency of Zn(2+), PO4 (3-) with a decrease in flow rate.

  17. Recycling process for recovery of gallium from GaN an e-waste of LED industry through ball milling, annealing and leaching

    Energy Technology Data Exchange (ETDEWEB)

    Swain, Basudev, E-mail: swain@iae.re.kr; Mishra, Chinmayee; Kang, Leeseung; Park, Kyung-Soo, E-mail: kspark@iae.re.kr; Lee, Chan Gi; Hong, Hyun Seon, E-mail: hshong@iae.re.kr

    2015-04-15

    Waste dust generated during manufacturing of LED contains significant amounts of gallium and indium, needs suitable treatment and can be an important resource for recovery. The LED industry waste dust contains primarily gallium as GaN. Leaching followed by purification technology is the green and clean technology. To develop treatment and recycling technology of these GaN bearing e-waste, leaching is the primary stage. In our current investigation possible process for treatment and quantitative leaching of gallium and indium from the GaN bearing e-waste or waste of LED industry dust has been developed. To recycle the waste and quantitative leaching of gallium, two different process flow sheets have been proposed. In one, process first the GaN of the waste the LED industry dust was leached at the optimum condition. Subsequently, the leach residue was mixed with Na{sub 2}CO{sub 3}, ball milled followed by annealing, again leached to recover gallium. In the second process, the waste LED industry dust was mixed with Na{sub 2}CO{sub 3}, after ball milling and annealing, followed acidic leaching. Without pretreatment, the gallium leaching was only 4.91 w/w % using 4 M HCl, 100 °C and pulp density of 20 g/L. After mechano-chemical processing, both these processes achieved 73.68 w/w % of gallium leaching at their optimum condition. The developed process can treat and recycle any e-waste containing GaN through ball milling, annealing and leaching. - Highlights: • Simplest process for treatment of GaN an LED industry waste developed. • The process developed recovers gallium from waste LED waste dust. • Thermal analysis and phase properties of GaN to Ga{sub 2}O{sub 3} and GaN to NaGaO{sub 2} revealed. • Solid-state chemistry involved in this process reported. • Quantitative leaching of the GaN was achieved.

  18. Ionic liquids as recyclable and separable reaction media in Rh-catalyzed decarbonylation of aromatic and aliphatic aldehydes

    DEFF Research Database (Denmark)

    Malcho, Phillip; Garcia-Suarez, Eduardo J.; Riisager, Anders

    2014-01-01

    Ionic liquids (ILs) have been applied as recyclable reaction media in the decarbonylation of aldehydes in the presence of a rhodium-phosphine complex catalyst. The performance of several new catalytic systems based on imidazolium-based ILs and [Rh(dppp)2]Cl (dppp: 1,3-diphenylphosphinopropane) were...

  19. Development of a correlation between slurry oil composition and process performance. Topical report 1. Analyses of slurry recycle oils from H-Coal PDU Run 5

    Energy Technology Data Exchange (ETDEWEB)

    Burke, F. P.; Winschel, R. A.; Pochapsky, T. C.

    1980-04-01

    Daily samples of the slurry recycle oil from the 30-day H-Coal PDU Run 5 (Syncrude mode, Illinois 6 coal) were analyzed by /sup 1/H-NMR spectroscopy GS/MS, and liquid chromatographic techniques. The recycle oils composition in PDU Run 5 reached an initial steady-state at about day 12, but this was upset when the hydrogen partial pressure was increased on day 20. The recycle oil composition was again approaching a steady-state by the end of the run. The distillates increased in aromaticity during the first 12 days of the run, as catalyst activity declined. The more aromatic distillates are better liquefaction media. Therefore, the solvent quality of the recycle distillates improved as the run progressed. The recycle distillates boiling below phenanthrene consist largely of cracking and isomerization products of hydrophenanthrenes. The relative ratios of reactants and products may be useful in establishing catalyst activity during the run. The start-up solvent had little effect on the run, because it was rapidly replaced by coal-derived recycle oils. The molecular weight distribution of the recycle resid (975/sup 0/F/sup +/, THF soluble) was relatively unchanged during the run although the ratio of benzene solubles to insolubles first decreased as catalyst activity declined, then increased with the increased hydrogen partial pressure during the last ten days of the run.

  20. Environmental performance and mechanical analysis of concrete containing recycled asphalt pavement (RAP) and waste precast concrete as aggregate.

    Science.gov (United States)

    Erdem, Savaş; Blankson, Marva Angela

    2014-01-15

    The overall objective of this research project was to investigate the feasibility of incorporating 100% recycled aggregates, either waste precast concrete or waste asphalt planning, as replacements for virgin aggregates in structural concrete and to determine the mechanical and environmental performance of concrete containing these aggregates. Four different types of concrete mixtures were designed with the same total water cement ratio (w/c=0.74) either by using natural aggregate as reference or by totally replacing the natural aggregate with recycled material. Ground granulated blast furnace slag (GGBS) was used as a mineral addition (35%) in all mixtures. The test results showed that it is possible to obtain satisfactory performance for strength characteristics of concrete containing recycled aggregates, if these aggregates are sourced from old precast concrete. However, from the perspective of the mechanical properties, the test results indicated that concrete with RAP aggregate cannot be used for structural applications. In terms of leaching, the results also showed that the environmental behaviour of the recycled aggregate concrete is similar to that of the natural aggregate concrete.

  1. Investigation of Ultrasonics as a tool for energy efficient recycling of Lactic acid from postconsumer PLA products

    Science.gov (United States)

    Srinivasan, Gowrishankar

    The growing use of "ecofriendly," biodegradable polymers have created a need for a suitable recycling technique because, unlike petroleum derived plastics, their properties deteriorate during conventional recycling. These new techniques must be cost efficient and yield material properties same as virgin polymer. This research investigates the effectiveness of high-power ultrasonics as an efficient technique to recover lactic acid from postconsumer polylactic acid (PLA) products. Polylactic acid is a commercially available bioplastic derived from corn starch and/or sugar cane that is biorenewable and compostable (biodegradable). The various ongoing researches to recover lactic acid from PLA employ a common platform of high temperature, high pressure (HTHP) to effect polymer hydrolysis. The energy intensiveness of these HTHP processes prompted this work to investigate ultrasonics as an low energy alternative process to cause PLA depolymerization. The energy consumption and the time required for depolymerization were utilized as the metrics to quantify and compare depolymerization enhanced by ultrasonics with hot-bath technique. The coupled effect of catalysts concentration and different solvents, along with ultrasonic were studied based on preliminary trial results. In addition, the correlation between the rates of de-polymerization was analyzed for ultrasonic amplitude, treatment time, and catalyst concentration and types. The results indicate that depolymerization of PLA was largely effected by heating caused by ultrasonic-induced cavitations. Other effects of ultrasonics, namely cavitations and acoustic streaming, were shown to have minimal effects in enhancing depolymerization. In fact, thermal energy predominately affected the reaction kinetics; the heat introduced by conventional method (i.e., electrical heaters) was more efficient than ultrasonic heating in terms of energy (for depolymerization) per unit mass of PLA and depolymerizing time. The degree of

  2. Design, develop, and manufacture process gas lubricated hot recycle gas circulators. Final technical report, MTI--77TR5

    Energy Technology Data Exchange (ETDEWEB)

    Dominy, D.G.; Hurley, J.D.

    1976-10-01

    In the SYNTHANE coal gasification process raw product gas of approximately 35 mole % methane is passed through a methanator which increases the methane content (and heating value) to approximately 86 mole % methane. The reaction is highly exothermic. In order to limit the temperature rise of the reaction, high BTU methane process gas is diluted with raw product gas. A pressure increase is necessary to force the mixed gases back into the methanator. In addition, varying recycle ratios affect the total flow of the gas stream necessitating a compressor or other device to operate at varying flow capacities. The present hot gas recycle methanator system utilized an eductor to mix and raise the pressure of the product gas. This method has limitations. The pressure rise is small, in the order of 1/2 psig, and the eductor does not allow proper mixing pressures and temperatures if the flow conditions are changed. An eductor is useful for this purpose only in a pilot plant and represents an expedient solution to the problem. For commercial use a compressor is essential.

  3. Nanoparticles as recyclable catalysts: the frontier between homogeneous and heterogeneous catalysis.

    Science.gov (United States)

    Astruc, Didier; Lu, Feng; Aranzaes, Jaime Ruiz

    2005-12-01

    Interest in catalysis by metal nanoparticles (NPs) is increasing dramatically, as reflected by the large number of publications in the last five years. This field, "semi-heterogeneous catalysis", is at the frontier between homogeneous and heterogeneous catalysis, and progress has been made in the efficiency and selectivity of reactions and recovery and recyclability of the catalytic materials. Usually NP catalysts are prepared from a metal salt, a reducing agent, and a stabilizer and are supported on an oxide, charcoal, or a zeolite. Besides the polymers and oxides that used to be employed as standard, innovative stabilizers, media, and supports have appeared, such as dendrimers, specific ligands, ionic liquids, surfactants, membranes, carbon nanotubes, and a variety of oxides. Ligand-free procedures have provided remarkable results with extremely low metal loading. The Review presents the recent developments and the use of NP catalysis in organic synthesis, for example, in hydrogenation and C--C coupling reactions, and the heterogeneous oxidation of CO on gold NPs.

  4. Incorporation of gypsum waste in ceramic block production: Proposal for a minimal battery of tests to evaluate technical and environmental viability of this recycling process.

    Science.gov (United States)

    Godinho-Castro, Alcione P; Testolin, Renan C; Janke, Leandro; Corrêa, Albertina X R; Radetski, Claudemir M

    2012-01-01

    Civil engineering-related construction and demolition debris is an important source of waste disposed of in municipal solid waste landfills. After clay materials, gypsum waste is the second largest contributor to the residential construction waste stream. As demand for sustainable building practices grows, interest in recovering gypsum waste from construction and demolition debris is increasing, but there is a lack of standardized tests to evaluate the technical and environmental viability of this solid waste recycling process. By recycling gypsum waste, natural deposits of gypsum might be conserved and high amounts of the waste by-product could be reused in the civil construction industry. In this context, this paper investigates a physical property (i.e., resistance to axial compression), the chemical composition and the ecotoxicological potential of ceramic blocks constructed with different proportions of clay, cement and gypsum waste, and assesses the feasibility of using a minimal battery of tests to evaluate the viability of this recycling process. Consideration of the results for the resistance to axial compression tests together with production costs revealed that the best formulation was 35% of plastic clay, 35% of non-plastic clay, 10% of Portland cement and 20% of gypsum waste, which showed a mean resistance of 4.64MPa. Energy dispersive X-ray spectrometry showed calcium and sulfur to be the main elements, while quartz, gypsum, ettringite and nacrite were the main crystalline compounds found in this formulation. Ecotoxicity tests showed that leachate from this formulation is weakly toxic toward daphnids and bacteria (EC(20%)=69.0 and 75.0, respectively), while for algae and fish the leachate samples were not toxic at the EC(50%) level. Overall, these results show that the addition of 20% of gypsum waste to the ceramic blocks could provide a viable substitute for clay in the ceramics industry and the tests applied in this study proved to be a useful tool

  5. Influence of photon recycling effects in the operation and design of GaAs solar cells; Influencia del reciclaje de fotones en el funcionamiento y del diseno de las celulas solares de Arsenico de Galio

    Energy Technology Data Exchange (ETDEWEB)

    Balenzategui Manzanares, J. L.

    2005-07-01

    Photon recycling (PR) is the process by which photons internally emitted in a semiconductor can be re-absorbed by the material, giving as result new electron-hole pairs. Although this process has been receiving some international research from the Sixties, because their effects revealed as relevant in certain devices and materials (as in gallium arsenide), its influence in the operation of solar cells has been scarcely considered in the past. Thus deposited it has been demonstrated that one of its major effects is an enhancement of the radiative carrier lifetine, photon recycling is not usually taken into account in photovoltaic, neither in device modelling and simulation, nor from the perspective of taking advantage of the phenomenon to improve the efficiency of solar cells. This work describes the results of our investigations in the field of photon recycling. (Author)

  6. Plastic Recycling Experiments in Materials Education

    Science.gov (United States)

    Liu, Ping; Waskom, Tommy L.

    1996-01-01

    The objective of this project was to introduce a series of plastic recycling experiments to students in materials-related courses such as materials science, material technology and materials testing. With the plastic recycling experiments, students not only can learn the fundamentals of plastic processing and properties as in conventional materials courses, but also can be exposed to the issue of materials life cycle and the impact on society and environment.

  7. Study on recycling of waste rubbers as medium components for hydroponic culture of rose

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin-Kuk; Lee, Hyung-Gyu; Jeong, Byoung-Ryong; Hwang, Seung-Jae [Gyeongsang National Univ., Kumi(Korea)

    2000-06-30

    Recently, the efficient disposal of the waste rubber is necessary due to increasing amount of the waste rubbers. In this paper, method of recycling waste rubbers as components of medium for hydroponic rose culture was suggested. We investigated growth of rose, and macro- and micro-elements, pH and EC of the media amended with waste rubber. In the beginning of culture, stress symptoms such as thin brittle stem and incipient wilting were observed, but they disappeared in a few weeks. Concentration of Zn{sup 2+} in media at flowering increased in proportion to contents of waste tire in the media. pH of media at flowering were in the range of 5.70 to 6.35. Rose growth in all media, except in waste rock wool mixed with EPDM powder at 9:3 ratio, was normal and equivalent to the control in terms of stem length, number of stems harvested and fresh weight. (author). 10 refs., 5 tabs., 4 figs.

  8. Chemical recycling of scrap composites

    Science.gov (United States)

    Allred, Ronald E.; Salas, Richard M.

    1994-01-01

    There are no well-developed technologies for recycling composite materials other than grinding to produce fillers. New approaches are needed to reclaim these valuable resources. Chemical or tertiary recycling, conversion of polymers into low molecular weight hydrocarbons for reuse as chemicals or fuels, is emerging as the most practical means for obtaining value from waste plastics and composites. Adherent Technologies is exploring a low-temperature catalytic process for recycling plastics and composites. Laboratory results show that all types of plastics, thermosets as well as thermoplastics, can be converted in high yields to valuable hydrocarbon products. This novel catalytic process runs at 200 C, conversion times are rapid, the process is closed and, thus, nonpolluting, and no highly toxic gas or liquid products have been observed so no negative environmental impact will result from its implementation. Tests on reclamation of composite materials show that epoxy, imide, and engineering thermoplastic matrices can be converted to low molecular weight hydrocarbons leaving behind the reinforcing fibers for reuse as composite reinforcements in secondary, lower-performance applications. Chemical recycling is also a means to dispose of sensitive or classified organic materials without incineration and provides a means to eliminate or reduce mixed hazardous wastes containing organic materials.

  9. Development of a Prototype Automated Sorting System for Plastic Recycling

    Directory of Open Access Journals (Sweden)

    D. A. Wahab

    2006-01-01

    Full Text Available Automated sorting for plastic recyclables has been seen as the way forward in the plastic recycling industry. Automated sorting provides significant improvements in terms of efficiency and consistency in the sorting process. In the case of macro sorting, which is the most common type of automated sorting, efficiency is determined by the mechanical details of the material handling system as well as the detection system. This paper provides a review on the state of-the-art technologies that have been deployed by some of the recycling facilities abroad. The design and development of a cost effective prototype automated system for sorting plastic recyclables is proposed and discussed.

  10. Algal biofuels from urban wastewaters: maximizing biomass yield using nutrients recycled from hydrothermal processing of biomass.

    Science.gov (United States)

    Selvaratnam, T; Pegallapati, A K; Reddy, H; Kanapathipillai, N; Nirmalakhandan, N; Deng, S; Lammers, P J

    2015-04-01

    Recent studies have proposed algal cultivation in urban wastewaters for the dual purpose of waste treatment and bioenergy production from the resulting biomass. This study proposes an enhancement to this approach that integrates cultivation of an acidophilic strain, Galdieria sulphuraria 5587.1, in a closed photobioreactor (PBR); hydrothermal liquefaction (HTL) of the wet algal biomass; and recirculation of the nutrient-rich aqueous product (AP) of HTL to the PBR to achieve higher biomass productivity than that could be achieved with raw wastewater. The premise is that recycling nutrients in the AP can maintain optimal C, N and P levels in the PBR to maximize biomass growth to increase energy returns. Growth studies on the test species validated growth on AP derived from HTL at temperatures from 180 to 300°C. Doubling N and P concentrations over normal levels in wastewater resulted in biomass productivity gains of 20-25% while N and P removal rates also doubled.

  11. Selective dissolution of halide perovskites as a step towards recycling solar cells

    Science.gov (United States)

    Kim, Byeong Jo; Kim, Dong Hoe; Kwon, Seung Lee; Park, So Yeon; Li, Zhen; Zhu, Kai; Jung, Hyun Suk

    2016-05-01

    Most research on perovskite solar cells has focused on improving power-conversion efficiency and stability. However, if one could refurbish perovskite solar cells, their stability might not be a critical issue. From the perspective of cost effectiveness, if failed, perovskite solar cells could be collected and recycled; reuse of their gold electrodes and transparent conducting glasses could reduce the price per watt of perovskite photovoltaic modules. Herein, we present a simple and effective method for removing the perovskite layer and reusing the mesoporous TiO2-coated transparent conducting glass substrate via selective dissolution. We find that the perovskite layer can be easily decomposed in polar aprotic solvents because of the reaction between polar aprotic solvents and Pb2+ cations. After 10 cycles of recycling, a mesoporous TiO2-coated transparent conducting glass substrate-based perovskite solar cell still shows a constant power-conversion efficiency, thereby demonstrating the possibility of recycling perovskite solar cells.

  12. FM dye photo-oxidation as a tool for monitoring membrane recycling in inner hair cells.

    Directory of Open Access Journals (Sweden)

    Dirk Kamin

    Full Text Available Styryl (FM dyes have been used for more than two decades to investigate exo- and endocytosis in conventional synapses. However, they are difficult to use in the inner hair cells of the auditory pathway (IHCs, as FM dyes appear to penetrate through mechanotransducer channels into the cytosol of IHCs, masking endocytotic uptake. To solve this problem we applied to IHCs the FM dye photo-oxidation technique, which renders the dyes into electron microscopy markers. Photo-oxidation allowed the unambiguous identification of labeled organelles, despite the presence of FM dye in the cytosol. This enabled us to describe the morphologies of several organelles that take up membrane in IHCs, both at rest and during stimulation. At rest, endosome-like organelles were detected in the region of the cuticular plate. Larger tubulo-cisternal organelles dominated the top and nuclear regions. Finally, the basal region, where the IHC active zones are located, contained few labeled organelles. Stimulation increased significantly membrane trafficking in the basal region, inducing the appearance of labeled vesicles and cistern-like organelles. The latter were replaced by small, synaptic-like vesicles during recovery after stimulation. In contrast, no changes in membrane trafficking were induced by stimulation in the cuticular plate region or in the top and nuclear regions. We conclude that synaptic vesicle recycling takes place mostly in the basal region of the IHCs. Other organelles participate in abundant constitutive membrane trafficking throughout the rest of the IHC volume.

  13. FM dye photo-oxidation as a tool for monitoring membrane recycling in inner hair cells.

    Science.gov (United States)

    Kamin, Dirk; Revelo, Natalia H; Rizzoli, Silvio O

    2014-01-01

    Styryl (FM) dyes have been used for more than two decades to investigate exo- and endocytosis in conventional synapses. However, they are difficult to use in the inner hair cells of the auditory pathway (IHCs), as FM dyes appear to penetrate through mechanotransducer channels into the cytosol of IHCs, masking endocytotic uptake. To solve this problem we applied to IHCs the FM dye photo-oxidation technique, which renders the dyes into electron microscopy markers. Photo-oxidation allowed the unambiguous identification of labeled organelles, despite the presence of FM dye in the cytosol. This enabled us to describe the morphologies of several organelles that take up membrane in IHCs, both at rest and during stimulation. At rest, endosome-like organelles were detected in the region of the cuticular plate. Larger tubulo-cisternal organelles dominated the top and nuclear regions. Finally, the basal region, where the IHC active zones are located, contained few labeled organelles. Stimulation increased significantly membrane trafficking in the basal region, inducing the appearance of labeled vesicles and cistern-like organelles. The latter were replaced by small, synaptic-like vesicles during recovery after stimulation. In contrast, no changes in membrane trafficking were induced by stimulation in the cuticular plate region or in the top and nuclear regions. We conclude that synaptic vesicle recycling takes place mostly in the basal region of the IHCs. Other organelles participate in abundant constitutive membrane trafficking throughout the rest of the IHC volume.

  14. Bioresources inner-recycling between bioflocculation of Microcystis aeruginosa and its reutilization as a substrate for bioflocculant production

    Science.gov (United States)

    Xu, Liang; Huo, Mingxin; Sun, Caiyun; Cui, Xiaochun; Zhou, Dandan; Crittenden, John C.; Yang, Wu

    2017-01-01

    Bioflocculation, being environmental-friendly and highly efficient, is considered to be a promising method to harvest microalgae. However, one limitation of this technology is high expense on substrates for bioflocculant bacteria cultivation. In this regard, we developed an innovative method for the inner-recycling of biomass that could harvest the typical microalgae, Microcystis aeruginosa, using a bioflocculant produced by Citrobacter sp. AzoR-1. In turn, the flocculated algal biomass could be reutilized as a substrate for Citrobacter sp. AzoR-1 cultivation and bioflocculant production. The experimental results showed that 3.4 ± 0.1 g of bioflocculant (hereafter called MBF-12) was produced by 10 g/L of wet biomass of M. aeruginosa (high-pressure steam sterilized) with an additional 10 g/L of glucose as an extra carbon source. The efficiency of MBF-12 for M. aeruginosa harvesting could reach ~95% under the optimized condition. Further analysis showed that MBF-12, dominated by ~270 kDa biopolymers, contributed the bioflocculation mechanisms of interparticle bridging and biosorption process. Bioflocculant synthesis by Citrobacter sp. AzoR-1 using microalga as a substrate, including the polyketide sugar unit, lipopolysaccharide, peptidoglycan and terpenoid backbone pathways. Our research provides the first evidence that harvested algae can be reutilized as a substrate to grow a bioflocculant using Citrobacter sp. AzoR-1. PMID:28252111

  15. Bioresources inner-recycling between bioflocculation of Microcystis aeruginosa and its reutilization as a substrate for bioflocculant production

    Science.gov (United States)

    Xu, Liang; Huo, Mingxin; Sun, Caiyun; Cui, Xiaochun; Zhou, Dandan; Crittenden, John C.; Yang, Wu

    2017-03-01

    Bioflocculation, being environmental-friendly and highly efficient, is considered to be a promising method to harvest microalgae. However, one limitation of this technology is high expense on substrates for bioflocculant bacteria cultivation. In this regard, we developed an innovative method for the inner-recycling of biomass that could harvest the typical microalgae, Microcystis aeruginosa, using a bioflocculant produced by Citrobacter sp. AzoR-1. In turn, the flocculated algal biomass could be reutilized as a substrate for Citrobacter sp. AzoR-1 cultivation and bioflocculant production. The experimental results showed that 3.4 ± 0.1 g of bioflocculant (hereafter called MBF-12) was produced by 10 g/L of wet biomass of M. aeruginosa (high-pressure steam sterilized) with an additional 10 g/L of glucose as an extra carbon source. The efficiency of MBF-12 for M. aeruginosa harvesting could reach ~95% under the optimized condition. Further analysis showed that MBF-12, dominated by ~270 kDa biopolymers, contributed the bioflocculation mechanisms of interparticle bridging and biosorption process. Bioflocculant synthesis by Citrobacter sp. AzoR-1 using microalga as a substrate, including the polyketide sugar unit, lipopolysaccharide, peptidoglycan and terpenoid backbone pathways. Our research provides the first evidence that harvested algae can be reutilized as a substrate to grow a bioflocculant using Citrobacter sp. AzoR-1.

  16. New biotechnological perspectives of a NADH oxidase variant from Thermus thermophilus HB27 as NAD+-recycling enzyme

    Directory of Open Access Journals (Sweden)

    Rocha-Martín Javier

    2011-11-01

    Full Text Available Abstract Background The number of biotransformations that use nicotinamide recycling systems is exponentially growing. For this reason one of the current challenges in biocatalysis is to develop and optimize more simple and efficient cofactor recycling systems. One promising approach to regenerate NAD+ pools is the use of NADH-oxidases that reduce oxygen to hydrogen peroxide while oxidizing NADH to NAD+. This class of enzymes may be applied to asymmetric reduction of prochiral substrates in order to obtain enantiopure compounds. Results The NADH-oxidase (NOX presented here is a flavoenzyme which needs exogenous FAD or FMN to reach its maximum velocity. Interestingly, this enzyme is 6-fold hyperactivated by incubation at high temperatures (80°C under limiting concentrations of flavin cofactor, a change that remains stable even at low temperatures (37°C. The hyperactivated form presented a high specific activity (37.5 U/mg at low temperatures despite isolation from a thermophile source. Immobilization of NOX onto agarose activated with glyoxyl groups yielded the most stable enzyme preparation (6-fold more stable than the hyperactivated soluble enzyme. The immobilized derivative was able to be reactivated under physiological conditions after inactivation by high solvent concentrations. The inactivation/reactivation cycle could be repeated at least three times, recovering full NOX activity in all cases after the reactivation step. This immobilized catalyst is presented as a recycling partner for a thermophile alcohol dehydrogenase in order to perform the kinetic resolution secondary alcohols. Conclusion We have designed, developed and characterized a heterogeneous and robust biocatalyst which has been used as recycling partner in the kinetic resolution of rac-1-phenylethanol. The high stability along with its capability to be reactivated makes this biocatalyst highly re-useable for cofactor recycling in redox biotransformations.

  17. Recycling ground granulated blast furnace slag as cold bonded artificial aggregate partially used in self-compacting concrete.

    Science.gov (United States)

    Gesoğlu, Mehmet; Güneyisi, Erhan; Mahmood, Swara Fuad; Öz, Hatice Öznur; Mermerdaş, Kasım

    2012-10-15

    Ground granulated blast furnace slag (GGBFS), a by-product from iron industry, was recycled as artificial coarse aggregate through cold bonding pelletization process. The artificial slag aggregates (ASA) replaced partially the natural coarse aggregates in production of self-compacting concrete (SCC). Moreover, as being one of the most widely used mineral admixtures in concrete industry, fly ash (FA) was incorporated as a part of total binder content to impart desired fluidity to SCCs. A total of six concrete mixtures having various ASA replacement levels (0%, 20%, 40%, 60%, and 100%) were designed with a water-to-binder (w/b) ratio of 0.32. Fresh properties of self-compacting concretes (SCC) were observed through slump flow time, flow diameter, V-funnel flow time, and L-box filling height ratio. Compressive strength of hardened SCCs was also determined at 28 days of curing. It was observed that increasing the replacement level of ASA resulted in decrease in the amount of superplasticizer to achieve a constant slump flow diameter. Moreover, passing ability and viscosity of SCC's enhanced with increasing the amount of ASA in the concrete. The maximum compressive strength was achieved for the SCC having 60% ASA replacement.

  18. Proposal of recycling system for waste aluminum

    Directory of Open Access Journals (Sweden)

    Š. Valenčík

    2008-04-01

    Full Text Available Introduced work is focused on waste aluminum recycling process with objective to propose complex production system for recovering of aluminum and some aluminum alloys. Solution is supported by extended analysis concerning purpose, basis and system sequences for recyclation. Based on that, sources, possibilities and conditions for recycling are formed. This has been used in proposal of manufacturing system. The principle is the structural proposal of manufacturing system, which does not only differentiate the stage of aluminum melting process, but also related stages as gross separation, sizing, containerisation and batching, palletisation, stacking and some related operations. Production system respects technological specifications, requirements for rationalisation of manufacturing systems, technical and economical feasibility conditions and is considered in lower automation level. However production system solves complex problem of recycling of some types of aluminum, it improves flexibility, production, quality (melting by high enforcements and in protective atmosphere and extention of production (final products production.

  19. Recycling agriculture wastes of ramie stalk as bioadsorbents for Cd(2+) removal: a kinetic and thermodynamic study.

    Science.gov (United States)

    Xu, S; Gong, X F; Zou, H L; Liu, C Y; Chen, C L; Zeng, X X

    2016-01-01

    In this study, we exhibit the recycling of agriculture wastes of ramie stalk as bioadsorbents for Cd(2+) removal. Based on our experimental results, it is realized that Cd(2+) adsorption to ramie stalk is highly pH sensitive, indicating the adsorption is driven by surface complexation reaction. The high adsorption capacity of ramie stalk toward Cd(2+) (qm = 10.33 mg g(-1), 0.09 mol-Cd g(-1)), which corresponds to around 21.95% of active adsorption sites available of ramie stalk, is believed to be closely related to its high cellulose and lignin content. The inhomogeneous surface of ramie stalk due to the high cellulose and lignin content also accounts for the observation that the adsorption kinetic is described well by the pseudo second order kinetic model. Results from thermodynamic studies suggest that the adsorption process is endothermic and spontaneous. All these properties demonstrate the potential of ramie stalk as a low cost bioadsorbent for the application of heavy metal removal.

  20. The Resource Benefits Evaluation Model on Remanufacturing Processes of End-of-Life Construction Machinery under the Uncertainty in Recycling Price

    Directory of Open Access Journals (Sweden)

    Qian-wang Deng

    2017-02-01

    Full Text Available In the process of end-of-life construction machinery remanufacturing, the existence of uncertainties in all aspects of the remanufacturing process increase the difficulty and complexity of resource benefits evaluation for them. To quantify the effects of those uncertainty factors, this paper makes a mathematical analysis of the recycling and remanufacturing processes, building a resource benefits evaluation model for the end-of-life construction machinery. The recycling price and the profits of remanufacturers can thereby be obtained with a maximum remanufacturing resource benefit. The study investigates the change regularity of the resource benefits, recycling price, and profits of remanufacturers when the recycling price, quality fluctuation coefficient, demand coefficient, and the reusing ratio of products or parts are varying. In the numerical experiment, we explore the effects of uncertainties on the remanufacturing decisions and the total expected costs. The simulated analysis shows when the quality fluctuation coefficient is approaching to 1, the values of the profits of remanufacturer, the maximal resource benefits and recycling price grade into constants.

  1. Recycling - Danish Waste Management Strategy

    DEFF Research Database (Denmark)

    Romann, Anne Funch; Thøgersen, John; Husmer, Lis

    The report challanges recycling as the only waste handling strategy. The tonnes of recycled materials should not be the only goal - it is essential to minimize the waste production and focus on eliminating hazardous materials.......The report challanges recycling as the only waste handling strategy. The tonnes of recycled materials should not be the only goal - it is essential to minimize the waste production and focus on eliminating hazardous materials....

  2. You're a "What"? Recycling Coordinator

    Science.gov (United States)

    Torpey, Elka Maria

    2011-01-01

    Recycling coordinators supervise curbside and dropoff recycling programs for municipal governments or private firms. Today, recycling is mandatory in many communities. And advancements in collection and processing methods have helped to increase the quantity of materials for which the recycling coordinator is responsible. In some communities,…

  3. The use of recycled paper processing residues in making porous brick with reduced thermal conductivity

    OpenAIRE

    SÜTÇÜ, Mücahit; AKKURT, Sedat

    2009-01-01

    Production of porous and light-weight bricks with reduced thermal conductivity and acceptable compressive strength is accomplished. Paper processing residues were used as an additive to an earthenware brick to produce the pores. SEM-EDS, XRD, XRF and TG-DTA analysis of the paper waste and brick raw material were performed. Mixtures containing brick raw materials and the paper waste were prepared at different proportions (up to 30 wt%). The granulated powder mixtures were compressed in a hydra...

  4. Water Recycling in Australia

    Directory of Open Access Journals (Sweden)

    Ross Young

    2011-09-01

    Full Text Available Australia is the driest inhabited continent on earth and, more importantly, experiences the most variable rainfall of all the continents on our planet. The vast majority of Australians live in large cities on the coast. Because wastewater treatments plants were all located near the coast, it was thought that large scale recycling would be problematic given the cost of infrastructure and pumping required to establish recycled water schemes. This all changed when Australia experienced a decade of record low rainfall and water utilities were given aggressive targets to increase the volume of water recycled. This resulted in recycled water being accepted as a legitimate source of water for non-drinking purposes in a diversified portfolio of water sources to mitigate climate risk. To ensure community support for recycled water, Australia lead the world in developing national guidelines for the various uses of recycled water to ensure the protection of public health and the environment. Australia now provides a great case study of the developments in maximizing water recycling opportunities from policy, regulatory and technological perspectives. This paper explores the evolution in thinking and how approaches to wastewater reuse has changed over the past 40 years from an effluent disposal issue to one of recognizing wastewater as a legitimate and valuable resource. Despite recycled water being a popular choice and being broadly embraced, the concept of indirect potable reuse schemes have lacked community and political support across Australia to date.

  5. Microbial carbon recycling: an underestimated process controlling soil carbon dynamics - Part 2: A C3-C4 vegetation change field labelling experiment

    Science.gov (United States)

    Basler, A.; Dippold, M.; Helfrich, M.; Dyckmans, J.

    2015-11-01

    The mean residence times (MRT) of different compound classes of soil organic matter (SOM) do not match their inherent recalcitrance to decomposition. One reason for this is the stabilization within the soil matrix, but recycling, i.e. the reuse of "old" organic material to form new biomass may also play a role as it uncouples the residence times of organic matter from the lifetime of discrete molecules in soil. We analysed soil sugar dynamics in a natural 30-year old labelling experiment after a wheat-maize vegetation change to determine the extent of recycling and stabilization by assessing differences in turnover dynamics between plant and microbial-derived sugars: while plant-derived sugars are only affected by stabilization processes, microbial sugars may be subject to both, stabilization and recycling. To disentangle the dynamics of soil sugars, we separated different density fractions (free particulate organic matter (fPOM), light occluded particulate organic matter (≤ 1.6 g cm-3; oPOM1.6), dense occluded particulate organic matter (≤ 2 g cm-3; oPOM2) and mineral-associated organic matter (> 2 g cm-3; mineral)) of a silty loam under long-term wheat and maize cultivation. The isotopic signature of neutral sugars was measured by high pressure liquid chromatography coupled to isotope ratio mass spectrometry (HPLC/IRMS), after hydrolysis with 4 M Trifluoroacetic acid. While apparent MRT of sugars were comparable to total organic carbon in the bulk soil and mineral fraction, the apparent MRT of sugar carbon in the oPOM fractions were considerably lower than those of the total carbon of these fractions. This indicates that oPOM formation was fuelled by microbial activity feeding on new plant input. In the bulk soil, MRT of the mainly plant-derived xylose were significantly lower than those of mainly microbial-derived sugars like galactose, rhamnose, fucose, indicating that recycling of organic matter is an important factor regulating organic matter dynamics in

  6. Effect of Aqueous Phase Recycling in Continuous Hydrothermal Liquefaction

    DEFF Research Database (Denmark)

    Klemmer, Maika; Madsen, René Bjerregaard; Houlberg, Kasper;

    2016-01-01

    The effect of recycling the aqueous phase in a continuous hydrothermal liquefaction process was investigated in terms of product yield distribution, carbon balance, and composition of all main fractions. Using a custom-built continuous reactor system, a long-term experiment was conducted at 350...... degrees C and 250 bar with a feedstock of dried distiller's grains with solubles. In two consecutive recycle experiments, the aqueous phase of the preceding experiment was used as dispersion medium for the feedstock preparation. In these recycle-experiments a significant increase in biocrude yields...... was observed with a maximum increase in the first recycle experiment. However, the recycling of the aqueous phase also resulted in lower heating values and higher water contents in the oil fraction. Based on these findings, recycling the aqueous phase is a trade-off between improved yields and reduced burn...

  7. Natures balancing act: examining biosynthesis de novo, recycling and processing damaged vitamin B metabolites.

    Science.gov (United States)

    Colinas, Maite; Fitzpatrick, Teresa B

    2015-06-01

    Plants use B vitamin compounds as cofactors for metabolism. Biosynthesis de novo of these metabolites in plants is almost fully elucidated. However, salvaging of precursors as well as cofactor derivatives is only being unraveled. Furthermore, processing of these compounds when damaged by cellular activities to prevent deleterious effects on metabolism is emerging. Recent investigations indicate that the role of B vitamins goes beyond metabolism and are being linked with epigenetic traits, specific developmental cues, the circadian clock, as well as abiotic and biotic stress responses. More in depth investigations on the regulation of the provision of these compounds through biosynthesis de novo, salvage and transport is suggesting that plants may share the cost of this load by division of labor.

  8. What do we know about metal recycling rates?

    Science.gov (United States)

    Graedel, T.E.; Allwood, J.; Birat, J.-P.; Buchert, M.; Hageluken, C.; Reck, B.K.; Sibley, S.F.; Sonnemann, G.

    2011-01-01

    The recycling of metals is widely viewed as a fruitful sustainability strategy, but little information is available on the degree to which recycling is actually taking place. This article provides an overview on the current knowledge of recycling rates for 60 metals. We propose various recycling metrics, discuss relevant aspects of recycling processes, and present current estimates on global end-of-life recycling rates (EOL-RR; i.e., the percentage of a metal in discards that is actually recycled), recycled content (RC), and old scrap ratios (OSRs; i.e., the share of old scrap in the total scrap flow). Because of increases in metal use over time and long metal in-use lifetimes, many RC values are low and will remain so for the foreseeable future. Because of relatively low efficiencies in the collection and processing of most discarded products, inherent limitations in recycling processes, and the fact that primary material is often relatively abundant and low-cost (which thereby keeps down the price of scrap), many EOL-RRs are very low: Only for 18 metals (silver, aluminum, gold, cobalt, chromium, copper, iron, manganese, niobium, nickel, lead, palladium, platinum, rhenium, rhodium, tin, titanium, and zinc) is the EOL-RR above 50% at present. Only for niobium, lead, and ruthenium is the RC above 50%, although 16 metals are in the 25% to 50% range. Thirteen metals have an OSR greater than 50%. These estimates may be used in considerations of whether recycling efficiencies can be improved; which metric could best encourage improved effectiveness in recycling; and an improved understanding of the dependence of recycling on economics, technology, and other factors. ?? 2011 by Yale University.

  9. A coupled advanced oxidation-biological process for recycling industrial wastewater containing persistent organic contaminants (CADOX)

    Energy Technology Data Exchange (ETDEWEB)

    Malato, S.; Blanco, J.; Maldonado, M.I.; Alarcon, D.C.; Fernandez, P.; Oller, I.; Gernjak, W. [Platforma Solar de Almeria, CIEMAT (Spain)

    2004-07-01

    This article concentrates on coupled processes to treat seven highly water-soluble pesticides and three non-biodegradable chlorinated solvents. These are considered priority substances by the European Union and are thus the focus of some attention. The coupled processes include three oxidation processes: photocatalysis by titanium dioxide, photo-Fenton, and ozone; as well as biological degradation. The article reports on work in progress. The full project will include building two small prototypes embodying these technologies, the construction of a demonstration treatment plant based on the results obtained from the prototypes, conceptual design of a full size plant. New solar collectors were built to facilitate the photocatalysis and photo-Fenton. To date it has been determined that the photo-catalysis and photo-Fenton are suitable if the concentrations of the above contaminants is high enough. Ozone can enhance the treatment in the case of the pesticides, but not in the case of the non-biodegradable chlorinated solvents. Biotreatment is also not suitable for the solvents. The best biological system has been determined and the optimal recovery of catalyst has also been found. 5 refs., 2 tabs., 4 figs.

  10. The chemical recycle of cotton

    Directory of Open Access Journals (Sweden)

    Alice Beyer Schuch

    2016-09-01

    Full Text Available The chemical recycle of cotton textiles and/or other cellulosic materials for the purpose of manufacturing regenerated high quality textiles fibres is a novel process. The objective of related research is based on the forecast of population growth, on resource scarcity predictions, and on the negative environmental impact of the textile industry. These facts lead the need of broadening the scope for long-term textile-to-textile recycle - as the mechanical recycle of natural fibres serve for limited number of cycles, still depends on input of virgin material, and offer a reduced-in-quality output. Critical analysis of scientific papers, relevant related reports, and personal interviews were the base of this study, which shows viable results in laboratorial scale of using low-quality cellulosic materials as input for the development of high-quality regenerated textile fibres though ecological chemical process. Nevertheless, to scale up and implement this innovative recycle method, other peripheral structures are requested, such as recover schemes or appropriate sort, for instance. Further researches should also be considered in regards to colours and impurities.

  11. A Highly Efficient Method for Synthesis of Bisarylmethylidenes of Cyclic Ketones in [BMIm]Cl/NaOH System as New and Recyclable Catalyst

    Directory of Open Access Journals (Sweden)

    Shahrzad Javanshir

    2014-03-01

    Full Text Available An ionic liquid 1-Butyl-3-methylimidazoliumchloride[BMIm]Cl/sodium hydroxide system, was employed as a catalyst for the fast and one-pot crossed aldol-condensation of various aromatic aldehydes and cyclic ketones, to produce a variety of substituted α,α'-bis(benzylidene-cycloalkanones under neat conditions. This process is simple, efficient and environmentally benign and proceeds in high yield and short reaction times. The ionic liquid can be recycled for subsequent reactions without any appreciable loss of efficiency.

  12. Biparametric potentiometric analytical microsystem for nitrate and potassium monitoring in water recycling processes for manned space missions.

    Science.gov (United States)

    Calvo-López, Antonio; Arasa-Puig, Eva; Puyol, Mar; Casalta, Joan Manel; Alonso-Chamarro, Julián

    2013-12-04

    The construction and evaluation of a Low Temperature Co-fired Ceramics (LTCC)-based continuous flow potentiometric microanalyzer prototype to simultaneously monitor the presence of two ions (potassium and nitrate) in samples from the water recycling process for future manned space missions is presented. The microsystem integrates microfluidics and the detection system in a single substrate and it is smaller than a credit card. The detection system is based on two ion-selective electrodes (ISEs), which are built using all-solid state nitrate and potassium polymeric membranes, and a screen-printed Ag/AgCl reference electrode. The obtained analytical features after the optimization of the microfluidic design and hydrodynamics are a linear range from 10 to 1000 mg L(-1) and from 1.9 to 155 mg L(-1) and a detection limit of 9.56 mg L(-1) and 0.81 mg L(-1) for nitrate and potassium ions respectively.

  13. Key technologies of layout design of recycling plants of waste refrigerators

    Institute of Scientific and Technical Information of China (English)

    L(U) Yi; LIU Zhi-feng; WANG Shu-wang; QI Yun-hui

    2005-01-01

    The present situations of waste refrigerators recycling and disposing were analyzed. Three key technologies of layout design of recycling plants of waste refrigerators were presented as follows: 1) establishment of recycling process of waste refrigerators; 2) the general plane layout of recycling plants; 3) the detailed layout of workshops of recycling plants. The focus of the three key technologies is to tackle the problem of the detailed layout ofworkshops of the recycling plants. By adopting Petri net, the model of logistics system of workshops was established and then optimized, and finally the detailed layout chart of recycling plants was gained. By adopting E-factory, the recycling plants were simulated. The results show that the method mentioned is effective.

  14. Sludge thermal oxidation processes: mineral recycling, energy impact, and greenhouse effect gases release

    Energy Technology Data Exchange (ETDEWEB)

    Guibelin, Eric

    2003-07-01

    Different treatment routes have been studied for a mixed sludge: the conventional agricultural use is compared with the thermal oxidation processes, including incineration (in gaseous phase) and wet air oxidation (in liquid phase). The interest of a sludge digestion prior to the final treatment has been also considered according to the two major criteria, which are the fossil energy utilisation and the greenhouse effect gases (CO{sub 2}, CH{sub 4}, N{sub 2}O) release. Thermal energy has to be recovered on thermal processes to make these processes environmentally friendly, otherwise their main interest is to extract or destroy micropollutants and pathogens from the carbon cycle. In case of continuous energy recovery, incineration can produce more energy than it consumes. Digestion is especially interesting for agriculture: according to these two schemes, the energy final balance can also be in excess. As to wet air oxidation, it is probably one of the best way to minimize greenhouse effect gases emission. (author)

  15. Development of research tool to evaluate the potential of using chlorella sorokiniana as bio-filter in recycled tilapia production

    OpenAIRE

    Latif, Muhammad Saqib

    2016-01-01

    The current study was attempted to develop the research tools in order to evaluate if Chlorella sorokiniana has a potential to perform as a bio-filter in recycle water tilapia production. The overall objective was to test the hypothesis that C. sorokiniana will effectively remove nitrogenous catabolites from the water and benefit the tilapia with oxygen and nutrients by photosynthesis. Removal of ammonia and nitrite from the water is improved by fertilization with phosphate, th...

  16. Modification of waste carpet with hydrated ferric oxide for recycling as an adsorbent material to recover phosphate from wastewater

    OpenAIRE

    Collinson, Simon R.; Duplá García, Oscar

    2013-01-01

    The surface of waste wool rich carpet was modified to enable recycling as an adsorbent material to remove pollutants from water and to avoid bulky carpets contributing to landfill. The proteins of the wool fibres in waste carpets adsorbed either copper(II) nitrate or iron(II) ions to form nanoparticles of Hydrated Ferric Oxide (HFO). The copper(II) ions reversibly bound to the wool carpet. The strongest binding of the nanoparticles of HFO occurred after first oxidizing the surface epicuticle ...

  17. Integración Óptima en el Sistema de Reciclado de Aguas en Procesos Papeleros Optimal Integration of Water Recycling Systems in Paper Manufacturing Processes

    Directory of Open Access Journals (Sweden)

    M González

    2004-01-01

    Full Text Available En este trabajo se propone un novedoso modelo de programación no lineal que resuelve el problema de minimizar el consumo de agua fresca utilizada en el proceso papelero, obteniendo considerables reducciones del agua consumida y de los residuos vertidos. Se determina el grado de contaminación de los flujos a ser reciclados, así como la máxima composición de contaminante que pueden aceptar los diferentes equipos y en base a esto se identifica la máxima posibilidad de reciclado de flujo de residuales al proceso. Se modela matemáticamente el problema y se obtienen como respuesta el mínimo consumo de agua fresca, el caudal máximo de residual vertido, la masa de fibra en suspensión que puede ser recuperada y la cantidad de contaminante a ser removida en el proceso. Se concluye que el modelo utilizado, es una herramienta sistemática, potente y genérica y puede ser utilizada en cualquier proceso de reducción de residuosThis work proposes a novel non-linear programming model that solves the problem of minimizing fresh water consumption in the paper manufacturing process, as well as reducing waste release. The degree of pollution of the flows to be recycled and the maximum contaminant composition treatable by different equipment units are determined; on the basis of this data, the maximum amount of recycleable residual flow is determined. The problem is modeled mathematically, determining the minimum consumption of fresh water, the maximum flow of waste water, the mass of fiber in suspension which can be recuperated, and the amount of pollutant to be removed in the process. It is concluded that the model used is a powerful generic systematic tool which can be used in any process for the reduction of residues

  18. Scientific Opinion on the safety assessment of the process RPC Cobelplast used to recycle post-consumer PET into food contact materials

    OpenAIRE

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF)

    2014-01-01

    This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the recycling process RPC Cobelplast (EU register No RECYC099) which is based on the Bandera® technology. The input of the process is washed and dried PET flakes originating from collected post-consumer PET containers, mainly bottles, containing no more than 5 % of PET from non-food consumer applications. Through this process, post-consumer washed a...

  19. Design and optimization of photovoltaics recycling infrastructure.

    Science.gov (United States)

    Choi, Jun-Ki; Fthenakis, Vasilis

    2010-11-15

    With the growing production and installation of photovoltaics (PV) around the world constrained by the limited availability of resources, end-of-life management of PV is becoming very important. A few major PV manufacturers currently are operating several PV recycling technologies at the process level. The management of the total recycling infrastructure, including reverse-logistics planning, is being started in Europe. In this paper, we overview the current status of photovoltaics recycling planning and discuss our mathematic modeling of the economic feasibility and the environmental viability of several PV recycling infrastructure scenarios in Germany; our findings suggest the optimum locations of the anticipated PV take-back centers. Short-term 5-10 year planning for PV manufacturing scraps is the focus of this article. Although we discuss the German situation, we expect the generic model will be applicable to any region, such as the whole of Europe and the United States.

  20. Design and Optimization of Photovoltaics Recycling Infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Choi, J.K.; Fthenakis, V.

    2010-10-01

    With the growing production and installation of photovoltaics (PV) around the world constrained by the limited availability of resources, end-of-life management of PV is becoming very important. A few major PV manufacturers currently are operating several PV recycling technologies at the process level. The management of the total recycling infrastructure, including reverse-logistics planning, is being started in Europe. In this paper, we overview the current status of photovoltaics recycling planning and discuss our mathematic modeling of the economic feasibility and the environmental viability of several PV recycling infrastructure scenarios in Germany; our findings suggest the optimum locations of the anticipated PV take-back centers. Short-term 5-10 year planning for PV manufacturing scraps is the focus of this article. Although we discuss the German situation, we expect the generic model will be applicable to any region, such as the whole of Europe and the United States.

  1. Pictet-Spengler condensation reactions catalyzed by a recyclable H~+-montmorillonite as a heterogeneous BrΦnsted acid

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Catalytic performance of different cation-exchanged montmorillonite clays has been investigated in the Pictet-Spengler C-C bond forming reaction.H+-Montmorillonite was found to be a very efficient and reusable catalyst for the endo cyclization of β-phenylethylamine derivatives with aldehydes under solvent-free conditions.In addition,an aqueous condensation version for the synthesis of tetrahydro-β-carbolines using the H+-montmorillonite catalyst has been developed.In these environmentally friendly processes,the use of organic solvents was avoided and the catalyst was recycled with maintenance of high catalytic activity.

  2. EFFECT OF RECYCLE TIRE ISOLATOR AS EARTHQUAKE RESISTANCE SYSTEM FOR LOW RISE BUILDINGS IN MALAYSIA

    Directory of Open Access Journals (Sweden)

    SOW WEI JIE

    2016-08-01

    Full Text Available The purpose of this research is to investigate the effect of Recycle Tire Isolator (RTI as earthquake resistance system for low rise buildings in Malaysia. Most of the earthquake’s victims are due to the collapse of poorly designed concrete and masonry buildings. Therefore, an economical but reliable RTI is introduced to solve the problem in most of the developing countries such as Malaysia. This study focuses on the effect of RTI-5 (5 layers RTI in protecting three stories buildings. The vertical displacement of RTI-5 was determined through static compression test. The maximum vertical displacement of RTI-5 was obtained when the specimen was monotonically loaded to failure. Finite element analysis was carried out by using ANSYS V16.0 to model the RTI-5 and the results obtained were compared to the experimental results. The dynamic stiffness and damping ratio of RTI-5 were investigated through dynamic test. The behaviour of various thickness of RTI were examined and compared with Rubber Bearing (RB and Scrap Tire Rubber Pad (STRP.Total displacement of three stories buildings on fixed base and on base isolation were determined. The results from static compression test and finite element analysis showed that RTI-5 could sustain a vertical load of 380 kN with vertical deformation of 12.5 mm. It has been verified by finite element analysis (FEA where both of the results achieved close agreement in terms of vertical deformation. RTI-5 and STRP have similar vertical stiffness due to the employment of same material in fabrication. However, rubber bearing is stiffer than RTI-5 due to the present of embedded steel plates. Besides, RTI-4 is stiffer than RTI-5 due to the number of layers are lesser in RTI-4. The results of dynamic test shown that RTI-5 has higher damping ratio than RTI-4. In overall, total deformation at the top floor of the three stories building is reduced by 83% via implementation of RTI in the base of the building. It has been proven

  3. Ferlins Show Tissue-Specific Expression and Segregate as Plasma Membrane/Late Endosomal or Trans-Golgi/Recycling Ferlins.

    Science.gov (United States)

    Redpath, Gregory M I; Sophocleous, Reece A; Turnbull, Lynne; Whitchurch, Cynthia B; Cooper, Sandra T

    2016-03-01

    Ferlins are a family of transmembrane-anchored vesicle fusion proteins uniquely characterized by 5-7 tandem cytoplasmic C2 domains, Ca(2+)-regulated phospholipid-binding domains that regulate vesicle fusion in the synaptotagmin family. In humans, dysferlin mutations cause limb-girdle muscular dystrophy type 2B (LGMD2B) due to defective Ca(2+)-dependent, vesicle-mediated membrane repair and otoferlin mutations cause non-syndromic deafness due to defective Ca(2+)-triggered auditory neurotransmission. In this study, we describe the tissue-specific expression, subcellular localization and endocytic trafficking of the ferlin family. Studies of endosomal transit together with 3D-structured illumination microscopy reveals dysferlin and myoferlin are abundantly expressed at the PM and cycle to Rab7-positive late endosomes, supporting potential roles in the late-endosomal pathway. In contrast, Fer1L6 shows concentrated localization to a specific compartment of the trans-Golgi/recycling endosome, cycling rapidly between this compartment and the PM via Rab11 recycling endosomes. Otoferlin also shows trans-Golgi to PM cycling, with very low levels of PM otoferlin suggesting either brief PM residence, or rare incorporation of otoferlin molecules into the PM. Thus, type-I and type-II ferlins segregate as PM/late-endosomal or trans-Golgi/recycling ferlins, consistent with different ferlins mediating vesicle fusion events in specific subcellular locations.

  4. Temperature Control in the Process of Hot In- place Recycling Construction%就地热再生施工过程中的温度控制

    Institute of Scientific and Technical Information of China (English)

    曹武安

    2012-01-01

    从热再生现场外界环境温度、加热温度、再生剂温度、新料温度及碾压温度五个方面,对就地热再生施工过程中现场温度控制要点进行阐述。。%In situ temperature control points in the process of hot in - place recycling construction are elabora- ted from five aspects of external environment temperature, heating temperature, temperature of regenerating agent, temperature of new material and roiling temperature of hot recycling site.

  5. Recycling Wood Composite Panels: Characterizing Recycled Materials

    Directory of Open Access Journals (Sweden)

    Hui Wan

    2014-10-01

    Full Text Available Downgraded medium density fiberboard (MDF, particleboard (PB, and oriented strandboard (OSB panels were individually subjected to steam explosion treatment. Downgraded MDF and PB panels were separately treated with thermal chemical impregnation using 0.5% butanetetracarboxylic acid (BTCA. And downgraded PB panels were processed with mechanical hammermilling. The pH, buffer capacity, fiber length, and particle size of these recycled materials were evaluated. After the steam explosion and thermal chemical impregnation treatments, the pH and buffer capacity of recycled urea formaldehyde resin (UF-bonded MDF and PB furnishes increased and the fiber length decreased. The hammermilling of recycled PB was less likely to break particles down into sizes less than 1 mm2.

  6. Cleaner production of citric acid by recycling its extraction wastewater treated with anaerobic digestion and electrodialysis in an integrated citric acid-methane production process.

    Science.gov (United States)

    Xu, Jian; Su, Xian-Feng; Bao, Jia-Wei; Chen, Yang-Qiu; Zhang, Hong-Jian; Tang, Lei; Wang, Ke; Zhang, Jian-Hua; Chen, Xu-Sheng; Mao, Zhong-Gui

    2015-01-01

    To solve the pollution problem of extraction wastewater in citric acid production, an integrated citric acid-methane production process was proposed. Extraction wastewater was treated through anaerobic digestion and the anaerobic digestion effluent (ADE) was recycled for the next batch of citric acid fermentation, thus eliminating wastewater discharge and reducing water consumption. Excessive Na(+) contained in ADE could significantly inhibit citric acid fermentation in recycling and was removed by electrodialysis in this paper. Electrodialysis performance was improved after pretreatment of ADE with air stripping and activated carbon adsorption to remove precipitable metal ions and pigments. Moreover, the concentrate water was recycled and mixed with feed to improve the water recovery rate above 95% in electrodialysis treatment, while the dilute water was collected for citric acid fermentation. The removal rate of Na(+) in ADE was above 95% and the citric acid production was even higher than that with tap water.

  7. Development And Initial Testing Of Off-Gas Recycle Liquid From The WTP Low Activity Waste Vitrification Process - 14333

    Energy Technology Data Exchange (ETDEWEB)

    McCabe, Daniel J.; Wilmarth, William R.; Nash, Charles A.; Taylor-Pashow, Kathryn M.; Adamson, Duane J.; Crawford, Charles L.; Morse, Megan M.

    2014-01-07

    The Waste Treatment and Immobilization Plant (WTP) process flow was designed to pre-treat feed from the Hanford tank farms, separate it into a High Level Waste (HLW) and Low Activity Waste (LAW) fraction and vitrify each fraction in separate facilities. Vitrification of the waste generates an aqueous condensate stream from the off-gas processes. This stream originates from two off-gas treatment unit operations, the Submerged Bed Scrubber (SBS) and the Wet Electrospray Precipitator (WESP). Currently, the baseline plan for disposition of the stream from the LAW melter is to recycle it to the Pretreatment facility where it gets evaporated and processed into the LAW melter again. If the Pretreatment facility is not available, the baseline disposition pathway is not viable. Additionally, some components in the stream are volatile at melter temperatures, thereby accumulating to high concentrations in the scrubbed stream. It would be highly beneficial to divert this stream to an alternate disposition path to alleviate the close-coupled operation of the LAW vitrification and Pretreatment facilities, and to improve long-term throughput and efficiency of the WTP system. In order to determine an alternate disposition path for the LAW SBS/WESP Recycle stream, a range of options are being studied. A simulant of the LAW Off-Gas Condensate was developed, based on the projected composition of this stream, and comparison with pilot-scale testing. The primary radionuclide that vaporizes and accumulates in the stream is Tc-99, but small amounts of several other radionuclides are also projected to be present in this stream. The processes being investigated for managing this stream includes evaporation and radionuclide removal via precipitation and adsorption. During evaporation, it is of interest to investigate the formation of insoluble solids to avoid scaling and plugging of equipment. Key parameters for radionuclide removal include identifying effective precipitation or ion

  8. Recycling of solid wastes in Mexico City in livestock and agricultural production systems as a sustainable alternative

    OpenAIRE

    Losada, H.; J. Cortes; Rivera, J.; Vargas, J.

    2011-01-01

    The use of solid organic wastes (manure and  fruit and vegetable refusals) as a way to recycle rubbish from peri-urban areas for the production of crops for local consumption, has been designated by some researchers as an alternate method to partially reduce city waste disposal problems as well as to generate employment and promote the consumption of local products. This model production has also been suggested as a closed system ideally suited for urban environments in order to reduce the us...

  9. Low H2O/Ce in Icelandic basalts as evidence for crustal recycling

    Science.gov (United States)

    Neave, David; Shorttle, Oliver; Hartley, Margaret; Maclennan, John

    2016-04-01

    The generation of new crust at mid-ocean ridges is balanced by the subduction of partially hydrothermally altered basaltic material back into the mantle. This subducted material may then be recycled and returned via mantle plumes to the Earth's surface at hot spots. Long-identified isotopic and trace element signatures of oceanic crust recycling in ocean island basalts (OIBs) have been recently supplemented by evidence of major element, i.e. lithological, heterogeneity in the melting region. For example, combined major and trace element systematics from Iceland suggest that the mantle source contains at least 5% recycled basalt. Observations of high water (H2O) contents in subglacially quenched basalts from Iceland have previously been attributed to the incorporation of wet recycled material into the mantle source. However, when combined with trace element analyses, recent volatile analyses from the Laki-Grímsvötn and Bárðarbunga-Veiðivötn systems in the Eastern Volcanic Zone (EVZ) of Iceland suggest that the underlying mantle is comparatively depleted in H2O for its degree of major and trace element enrichment. Correlations between H2O and cerium (Ce) within individual mid-ocean ridge basalt (MORB) suites reveal that these elements partition similarly prior to H2O degassing at low pressures; H2O/Ce remains constant during melting and fractionation, and hence reflects the average H2O/Ce of the melting region. MORBs from the Mid-Atlantic Ridge south of Iceland have a mean H2O/Ce value of 304±48 at a mean La/Yb of 2.1±1.5. In contrast, basalts from the EVZ have a lower mean H2O/Ce of 180±20 at a higher mean La/Yb of 3.1±0.5. Thus, despite coming from an enriched section of the Mid-Atlantic ridge in terms of trace element content, basalts from the EVZ have the lowest H2O/Ce values known from the ridge, and are hence comparatively depleted in H2O. Given that H2O/Ce from un-degassed basalts is considered to represent mantle source values, we suggest that low H

  10. Hydrothermal Processing of Base Camp Solid Wastes To Allow Onsite Recycling

    Science.gov (United States)

    2008-09-01

    Figure 4. Bouldin processing system used during the Fort Benning demonstration. Bobcat is loading the initial shredder with domestic waste from the pile...on the right. Shredder is followed by metal removal, a second shredder , grinder, and hydrolyzer (on left...converting it into usable end products. The system includes: two shredders , a grinder, a hydrothermal process (hydrolyzer), dryer, and par- ticle screens

  11. Pre-treatment of ligno-cellulose with biological acid recycling (the Biosulfurol process)

    NARCIS (Netherlands)

    Groenestijn, van J.W.; Hazewinkel, J.H.O.; Bakker, R.R.

    2008-01-01

    A biomass pretreatment process is being developed based on contacting ligno-cellulosic biomass with 70% sulphuric acid and subsequent hydrolysis by adding water. In this process, the hydrolysate can be fermented yielding ethanol, while the sulphuric acid is partly recovered by anion-selective membra

  12. The Essence of a Recycling Economy:Circular Utilization of Resources

    Institute of Scientific and Technical Information of China (English)

    Chen Demin

    2004-01-01

    By analyzing the relationship between a recycling economy and sustainable development theory, this article puts forward the basic concept of a recycling economy as a dynamic economic operational model, and explains the four basic characteristics. It is stressed that the essential element of a recycling economy is the use of resources circularly.In the end, this article analyzes the phenomena of utilizing the recycling economy concept incorrectly,and sets forth a number of problems that should be noted during the process of developing a recycling economy in China.

  13. Recycling of plastic waste by density separation: prospects for optimization.

    Science.gov (United States)

    Gent, Malcolm Richard; Menendez, Mario; Toraño, Javier; Diego, Isidro

    2009-03-01

    A review of existing industrial processing and results of alternative processing investigations for separating solid mixtures and specifically recycling plastic waste by density separation is presented. Media density separation is shown to be fundamental for separation and/or pre-concentration in the recycling of plastics. The current use of static media processes limits the capacity and size of material that can be treated commercially. Investigations have shown that the hydroscopic properties of plastics can be reduced to improve such separations. This indicates that an alternative processing method is required to increase the commercial recovery of recyclable plastics. Cylindroconical and cylindrical cyclone-type media separators, such as those used for processing coal, are reviewed and suggested as a potential substitute. Both have superior production capacities and are able to process a larger range in particle sizes treated. A summary of results of investigations with cyclone media devices for recycling plastics is presented.

  14. Recycling of Metals

    DEFF Research Database (Denmark)

    Damgaard, Anders; Christensen, Thomas Højlund

    2011-01-01

    Metals like iron and aluminium are produced from mineral ore and used for a range of products, some of which have very short lifetimes and thus constitute a major fraction of municipal waste. Packaging in terms of cans, foils and containers are products with a short lifetime. Other products like...... describes briefly how iron and aluminium are produced and how scrap metal is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of metal recycling. Copper and other metals are also found in waste but in much smaller...

  15. Current Status on Resource and Recycling Technology for Rare Earths

    Science.gov (United States)

    Takeda, Osamu; Okabe, Toru H.

    2014-06-01

    The development of recycling technologies for rare earths is essential for resource security and supply stability because high-quality rare earth mines are concentrated in China and the demand for rare earth metals such as neodymium and dysprosium, used as raw materials in permanent magnets (neodymium magnet), is expected to increase rapidly in the near future. It is also important to establish a recycling-based society from the perspective of the conservation of finite and valuable mineral resources and the reduction of the environmental load associated with mining and smelting. In this article, the current status of rare earth resource as well as that of recycling technology for the magnets is reviewed. The importance of establishing an efficient recycling process for rare earths is discussed from the characteristics of supply chain of rare earths, and the technological bases of the recycling processes for the magnet are introduced. Further, some fundamental researches on the development of new recycling processes based on pyrometallurgical process are introduced, and the features of the recycling processes are evaluated.

  16. Noble metal recycling. Project 2: Optimization of discontinuous thermal processes (emission reduction). Final report; Edelmetallrecycling. Teilvorhaben 2: Weiterentwicklung der Verfahrenstechnik bei diskontinuierlichen thermischen Prozessen (Emissionsminderung). Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Baumbach, G.; Berger, R.

    2000-10-01

    A batch operated incineration process, used for the recycling of precious metals is described in the report. The development of a new combined pyrolysis/oxidation Process is the main focus of the work. This new process has several remarkable advantages compared to traditionally used techniques. The optimisation of the process with a modern fuzzy based control technique is described in detail. The emissions of the process were reduced considerably applying the new process and the innovative control technique. Furthermore the layout of several components of the new process can be reduced in the future. The developed techniques can also be applied in other thermal processes, especially batch processes. Additionally the application of catalysts for PCDD/PCDF reduction in the flue gas upstream and downstream of the filter was investigated. Whereas the catalyst performed well, as expected, downstream of the filter, no acceptable operation was possible upstream of the filter. As the reheating downstream the filter is economically not feasible the application of catalysts is not applicable for the describe process. (orig.) [German] Die Arbeit beschreibt einen diskontinuierlichen thermischen Prozess, der zur Rueckgewinnung von Edelmetallen eingesetzt wird. Der Schwerpunkt der Arbeit liegt auf der Entwicklung eines neuartigen kombinierten Pyrolyse/Oxidations-Prozesses, der gegenueber den traditionell eingesetzten Anlagen grosse Vorteile aufweist. Die Optimierung dieses Prozesses mit Hilfe modernster Fuzzy-Regelungstechnik wird detailliert beschrieben. Mit dem neuen Verfahren und den innovativen Regelungstechniken konnten die Emissionen des Prozesses merklich gesenkt werden, ohne den Energiebedarf negativ zu beeinflussen. Ausserdem koennen zukuenftige Anlagen kleiner ausgelegt werden. Die entwickelten Verfahren koennen auch auf andere thermische Prozesse uebertragen werden. Weiterhin wurde der Einsatz von Katalysatoren zur PCDD/PCDF-Minderung im Rein- und Rohgas untersucht

  17. Recycling : An essential enterprise for resource conservation and sustainable development

    Energy Technology Data Exchange (ETDEWEB)

    Puvvada, G.V.K.; Sridhar, R.; Lakshmanan, V.I. [Process Research ORTECH, Mississauga, ON (Canada)

    2003-07-01

    The demand for both ferrous and non-ferrous metals is expected to increase despite the fact that ore reserves contain lower grade ore and are highly complex. The situation increases the pressure to adopt conservation measures such as recycling and reducing waste generation. This paper examined the recycling of essential metals such as copper, aluminum, iron and steel, as well as associated issues. It included a section on the importance of innovation in the recycling industry if it is to remain viable from an economic and environmental perspective. To better illustrate their discussion, the authors provided examples of several case studies that are either completed or underway at Process Research ORTECH Inc. The case studies dealt with the recycling of zinc from steel mill dust (EAF dusts), recycling of fly ash (innovative TORBED{sup TM} reactor), and the recovery of water from textile effluents (reverse osmosis, and mechanical vapor recompression evaporators). 15 refs., 3 tabs., 1 fig.

  18. Retirement as a Learning Process

    Science.gov (United States)

    Hodkinson, Phil; Ford, Geoff; Hodkinson, Heather; Hawthorn, Ruth

    2008-01-01

    This article draws upon a major qualitative empirical research investigation in Great Britain to explore the relationships between retirement and learning. Though retirement is frequently viewed as an event leading to a life stage, our data show that it can perhaps be best understood as a lengthy process. This process begins well before actual…

  19. Process Use as a Usefulism

    Science.gov (United States)

    Patton, Michael Quinn

    2007-01-01

    Process use refers to changes in attitude, thinking, and behavior that result from participating in an evaluation. Process use includes individual learnings from evaluation involvement as well as effects on program functioning and organizational culture. The "Encyclopedia of Social Science Research Methods," in an entry on operationalization,…

  20. Recycling of Glass

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Damgaard, Anders

    2011-01-01

    Glass is used for many purposes, but in the waste system glass is predominantly found in terms of beverage and food containers with a relatively short lifetime before ending up in the waste. Furthermore there is a large amount of flat glass used in building materials which also ends up in the waste...... system; this glass though has a long lifetime before ending up in the waste. Altogether these product types add up to 82% of the production of the European glass industry (IPCC, 2001). Recycling of glass in terms of cleaning and refilling of bottles as well as the use of broken glass in the production...... of new glass containers is well established in the glass industry. This chapter describes briefly howglass is produced and howwaste glass is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of glass recycling....

  1. Testicular membrane lipid damage by complex mixture of leachate from municipal battery recycling site as indication of idiopathic male infertility in rat.

    Science.gov (United States)

    Akintunde, Jacob K; Oboh, Ganiyu; Akindahunsi, Akintunde A

    2013-12-01

    Leachate from a municipal battery recycling site is a potent source of mixed-metal released into the environment. The present study investigated the degree at which mixed-metal exposure to the municipal auto-battery leachate (MABL) and to the Elewi Odo municipal auto-battery recycling site leachate (EOMABRL) affected the lipid membrane of the testes in in vitro experiment. The results showed elevated level of mixed-metals over the permissible levels in drinking water, as recommended by regulatory authorities. In the leachate samples, the levels of malondialdehyde (MDA), a biomarker of lipid damage, was significantly (pbattery leachate (MABL) was significantly (pbattery recycling site (EOMABRL). The testicular lipid membrane capacity was compromised following treatment with leachate from the municipal battery recycling site, implicating mixed-metal exposure as the causative agent of testicular damage and male infertility.

  2. 40 CFR 261.6 - Requirements for recyclable materials.

    Science.gov (United States)

    2010-07-01

    ... initiating the shipment. (ii) Scrap metal that is not excluded under § 261.4(a)(13); (iii) Fuels produced... recycling process itself is exempt from regulation except as provided in § 261.6(d).) (2) Owners...

  3. The processes of neuronal and recycling under the bias of implicit learning: literacy methods in focus

    OpenAIRE

    Guaresi, Ronei

    2011-01-01

    Based on advances in neuroscience and literature resulting from these advances, this text reflects on the acquisition of writing, specifically on methods of phonetic and global literacy, under the scope of implicit and explicit learning, in the acquisition of human language, essentially complex and arbitrary. This process will occur through the recuperation of the notion of connectionist learning and understanding of implicit and explicit. This theoretical recuperation arisen from discoveries...

  4. Synthesis of Fe3O4/Pt Nanoparticles Decorated Carbon Nanotubes and Their Use as Magnetically Recyclable Catalysts

    Directory of Open Access Journals (Sweden)

    Hongkun He

    2011-01-01

    Full Text Available We report a facile approach to prepare Fe3O4/Pt nanoparticles decorated carbon nanotubes (CNTs. The superparamagnetic Fe3O4 nanoparticles with average size of 4∼5 nm were loaded on the surfaces of carboxyl groups functionalized CNTs via a high-temperature solution-phase hydrolysis method from the raw material of FeCl3. The synthesis process of magnetic CNTs is green and readily scalable. The loading amounts of Fe3O4 nanopartilces and the magnetizations of the resulting magnetic CNTs show good tunability. The Pt nanopaticles with average size of 2.5 nm were deposited on the magnetic CNTs through a solution-based method. It is demonstrated that the Fe3O4/Pt nanoparticles decorated CNTs have high catalytic activity in the reduction reaction of 4-nitrophenol and can be readily recycled by a magnet and reused in the next reactions with high efficiencies for at least fifteen successive cycles. The novel CNTs-supported magnetically recyclable catalysts are promising in heterogeneous catalysis applications.

  5. Vegetable fibres from agricultural residues as thermo-mechanical reinforcement in recycled polypropylene-based green foams.

    Science.gov (United States)

    Ardanuy, Mònica; Antunes, Marcelo; Velasco, José Ignacio

    2012-02-01

    Novel lightweight composite foams based on recycled polypropylene reinforced with cellulosic fibres obtained from agricultural residues were prepared and characterized. These composites, initially prepared by melt-mixing recycled polypropylene with variable fibre concentrations (10-25 wt.%), were foamed by high-pressure CO(2) dissolution, a clean process which avoids the use of chemical blowing agents. With the aim of studying the influence of the fibre characteristics on the resultant foams, two chemical treatments were applied to the barley straw in order to increase the α-cellulose content of the fibres. The chemical composition, morphology and thermal stability of the fibres and composites were analyzed. Results indicate that fibre chemical treatment and later foaming of the composites resulted in foams with characteristic closed-cell microcellular structures, their specific storage modulus significantly increasing due to the higher stiffness of the fibres. The addition of the fibres also resulted in an increase in the glass transition temperature of PP in both the solid composites and more significantly in the foams.

  6. Testicular membrane lipid damage by complex mixture of leachate from municipal battery recycling site as indication of idiopathic male infertility in rat

    OpenAIRE

    Akintunde, Jacob K.; Oboh, Ganiyu; Akindahunsi, Akintunde A.

    2013-01-01

    Leachate from a municipal battery recycling site is a potent source of mixed-metal released into the environment. The present study investigated the degree at which mixed-metal exposure to the municipal auto-battery leachate (MABL) and to the Elewi Odo municipal auto-battery recycling site leachate (EOMABRL) affected the lipid membrane of the testes in in vitro experiment. The results showed elevated level of mixed-metals over the permissible levels in drinking water, as recommended by regula...

  7. Resrad-recycle: a computer model for analyzing radiation exposures resulting from recycling radioactively contaminated scrap metals or reusing radioactively surface-contaminated materials and equipment.

    Science.gov (United States)

    Cheng, Jing-Jy; Kassas, Bassel; Yu, Charley; Amish, John; LePoire, Dave; Chen, Shih-Yew; Williams, W A; Wallo, A; Peterson, H

    2004-11-01

    RESRAD-RECYCLE is a computer code designed by Argonne National Laboratory (ANL) to be used in making decisions about the disposition of radioactively contaminated materials and scrap metals. It implements a pathway analysis methodology to evaluate potential radiation exposures resulting from the recycling of contaminated scrap metals and the reuse of surface-contaminated materials and equipment. For modeling purposes, it divides the entire metal recycling process into six steps: (1) scrap delivery, (2) scrap melting, (3) ingot delivery, (4) product fabrication, (5) product distribution, and (6) use of finished product. RESRAD-RECYCLE considers the reuse of surface-contaminated materials in their original forms. It contains representative exposure scenarios for each recycling step and the reuse process; users can also specify scenarios if desired. The model calculates individual and collective population doses for workers involved in the recycling process and for the public using the finished products. The results are then used to derive clearance levels for the contaminated materials on the basis of input dose restrictions. The model accounts for radiological decay and ingrowth, dilution and partitioning during melting, and distribution of refined metal in the various finished products, as well as the varying densities and geometries of the radiation sources during the recycling process. A complete material balance in terms of mass and radioactivity during the recycling process can also be implemented. In an international validation study, the radiation doses calculated by RESRAD-RECYCLE were shown to agree fairly well with actual measurement data.

  8. Hydrometallurgical process for the recycling of copper using anodic oxidation of cuprous ammine complexes and flow-through electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Oishi, T.; Yaguchi, M.; Koyama, K.; Tanaka, M. [Metals Recycling Group, Research Institute for Environmental Management Technology, National Institute of Advanced Industrial Science and Technology (AIST), 16-1 Onogawa, Tsukuba, Ibaraki 305-8569 (Japan); Lee, J.-C. [Minerals and Materials Processing Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), 30 Gajeong-dong, Yuseong-ku, Daejeon 305-350 (Korea)

    2008-01-01

    Flow-through electrolysis for copper electrowinning from cuprous ammine complex was studied in order to develop a hydrometallurgical copper recycling process using an ammoniacal chloride solution, focusing on the anodic oxidation of cuprous to cupric ammine complexes. The current efficiency of this anodic oxidation was 96% at a current density of 200 A m{sup -2} under a batch condition. In a flow-through electrolysis using a sub-liter cell and a carbon felt anode, the anodic current efficiency increased with the flow rate and was typically higher than 97%. This tendency was explained by the backward flow of the cupric ammine complex, which was formed on the anode, through the diaphragm. The anodic overpotential was lower than 0.3 V even at an apparent current density of 1500 A m{sup -2}. A similar current efficiency and overpotential were also achieved in a liter scale cell, which indicates the scale flexibility of this electrolysis. The power consumption requirements for copper electrowinning in this cell were 460 and 770 kWh t{sup -1} at the current densities of 250 and 500 A m{sup -2}, respectively, which were much lower than that of the conventional copper electrowinning despite the longer interpolar distance. (author)

  9. Development of a ceramics filter technology for aluminum recycling. Discussion on an unnecessary constituent reducing process by means of solid-liquid separation; Recycle arumiyo ceramics filter gijutsu no kaihatsu. Koeki bunrini yoru fuyo seibun teigen process no kento

    Energy Technology Data Exchange (ETDEWEB)

    Saegusa, T.; Honma, K. [Hokkaido Electric Power Co. Inc., Sapporo (Japan); Narita, T.; Suzuki, T. [Hokkaido University, Sapporo (Japan); Matsubara, H.; Aoki, S. [Japan Fine Ceramics Center, Nagoya (Japan)

    2000-03-24

    A problem in recycling aluminum scraps is the existence of Fe and Pb as impurities, in addition to added alloy elements (Cu, Si, Mg and Zn). Discussion was given on an Fe concentration reducing method, in which molten Al-Cu-Fe-based alloy to simulate scrapped materials is filtered by an alumina ceramics filter at the solid-liquid phase coexisting temperature zone. The ceramics filter was formed by mixing thermally hardening resin into fine powder material. By using a method to drill through-holes during the forming stage, fine pores were optionally controlled in the sub-millimeter to millimeter order. In the filtration, if the Fe concentration is lower than that in the eutectic composition, Cu and Fe are condensed in the permeate phase, whereas primary crystal of aluminum is accumulated on the filter as the remaining phase, enhancing the aluminum purity. Filtration, repeated three times, has reduced the Fe concentration from 0.75 to 0.63% by atoms. If the Fe concentration is higher than eutectic concentration, since Fe is condensed in the form of intermetallic compound of FeAl{sub 3} as the remaining phase on the filter, the Fe concentration is reduced in the permeation phase, and three-time filtration reduced the Fe concentration from 1.5 to 0.70% by atoms. (NEDO)

  10. Scientific Opinion on the safety assessment of the process “MOPET-FLAKE” used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2014-04-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the recycling process MOPET-FLAKE (EU register number RECYC038. The input of the process is hot caustic washed and dried PET flakes originating from collected post-consumer PET containers, mainly bottles, containing no more than 5 % of PET from non-food consumer applications. Through this process, washed and dried PET flakes are being crystallised and solid state polymerised in a batch reactor. Having examined the challenge test provided, the Panel concluded that the crystallisation and solid state polymerisation (step 2 is the critical step that determines the decontamination efficiency of the process. The operating parameters to control its performance are well defined and are the temperature, the residence time, the pressure and the inert gas flow. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore the Panel concluded that the recycled PET obtained from this process intended to be used up to 100 % for the manufacture of materials and articles for contact with all types of foodstuffs for long term storage at room temperature, with or without hotfill is not considered of safety concern. The trays made of the recycled PET are not intended to be used and should not be used either in microwave or in conventional oven.

  11. Continuous high-temperature recycling of waste by the Thermoselect process; Unterbrechungsloses Hochtemperaturrecycling - Abfallveredelung durch Thermoselect

    Energy Technology Data Exchange (ETDEWEB)

    Stahlberg, R. [Thermoselect Engineering S.r.l., Verbania (Italy)

    1998-09-01

    Based on the experience with the Thermoselect plant at Fondotoce, Italy (100 Mg/d), which was commissioned in 1992, a 225,000 Mg/a plant with three units (720 Mg/d) is being constructed at Karlsruhe, Germany. The plant is scheduled for commissioning in 1998. The contribution presents the product balance, the approved emission levels, and the energy uses envisaged for the Karlsruhe project. Final product quality data and energy yields illustrate the differences from conventional thermal processes. An ecobalance comparing the Thermoselect process with grate furnaces shows that water, soil and air pollution is much reduced by the new Termoselect process. Apart from high product quality, the plant also has the advantage of reduced dumping cost and no long-term ecological hazards. (orig./SR) [Deutsch] Auf Basis der grosstechnischen Erfahrung mit einer seit 1992 in Fondotoce (Italien) betriebenen THERMOSELECT-Anlage (Kapazitaet 100 Mg/d), Restmuell umweltgerecht zu behandeln, wird 1998 der Aufbau einer 225.000 Mg/a-Anlage mit 3 Linien (720 Mg/d) in Karlsruhe (Deutschland) abgeschlossen. Die Produktebilanz und die genehmigten Emissionswerte sind in dem Artikel belegt. Gezeigt wird die fuer das Projekt Karlsruhe vorgesehene Energienutzung. Die Endprodduktqualitaeten und die Energieausbeute verdeutlichen die Unterschiede zu bisherigen konventionellen thermischen Verfahren. Eine erarbeitete Oekobilanz mit einem Vergleich von THERMOSELECT und Rostfeuerung zeigt die deutlich geringe Belastung der Umweltkompartimente Wasser, Boden und Luft durch das neue THERMOSELECT-Verfahren. Neben hohen Produktqualitaeten wird - verglichen mit traditionellen Techniken - ein deutlich verringerter Entsorgungspreis erreicht, wobei gleichzeitig oekologische Belastungen auszuschliessen sind. (orig./SR)

  12. A comparative study of recycled aggregates from concrete and mixed debris as material for unbound road sub-base

    Directory of Open Access Journals (Sweden)

    Jiménez, J. R.

    2011-06-01

    Full Text Available Seven different types of recycled aggregates from construction and demolition waste (CDW have been evaluated as granular materials for unbound road sub-bases construction. The results showed that recycled concrete aggregates complied with all specifications for using in the construction of unbound structural layers (sub-base for T3 and T4 traffic categories according to the Spanish General Technical Specification for Road Construction (PG-3. Some mixed recycled aggregates fell short of some specifications due to a high content of sulphur compounds and poor fragmentation resistance. Sieving off the fine fraction prior to crushing the mixed CDW reduce the total sulphur content and improve the quality of the mixed recycled aggregates, by contrast, pre-sieving concrete CDW had no effect on the quality of the resulting aggregates. The results were compared with a crushed limestone as natural aggregate.

    Siete áridos reciclados de residuos de construcción y demolición (RCD se han evaluado como zahorras para la construcción de sub-bases de carreteras. Los resultados muestran que los áridos reciclados de hormigón cumplen todas las especificaciones del Pliego de Prescripciones Técnicas Generales para Obras de Carreteras de España (PG-3 para su uso en capas estructurales (sub-base de las categorías de tráfico T3 y T4. Algunos áridos reciclados mixtos no cumplen por escaso margen algunas de las especificaciones, debido a un alto contenido de compuestos de azufre y a una menor resistencia a la fragmentación. El precribado de la fracción fina antes de la trituración de los RCD mixtos reduce el contenido de azufre total y mejora la calidad, por el contrario, el precribado de los RCD de hormigón no tiene ningún efecto sobre la calidad de los áridos reciclados. Los resultados se compararon con una zahorra artificial caliza como árido natural.

  13. Preparation of oxide powder by continuous oxidation process from recycled Fe-77Ni alloy scrap

    Science.gov (United States)

    Yun, J. Y.; Park, D. H.; Jung, G. J.; Wang, J. P.

    2015-12-01

    The oxidation behavior of Fe-77Ni alloy scrap was studied under a 0.2 atm oxygen partial pressure at the temperature range of 400°C to 900°C. The oxidation rate was found to be increased with an increase of temperature and followed the parabolic rate law with linearly proportional to temperature. Microstructure and cross-sectional area of the oxide layer were examined by SEM, EDX, and XRD. It could be speculated that rate-limiting step was controlled by diffusion through either the spinel structure or the NiO layer, both of which were present in this alloy during oxidation at elevated temperatures. In the long run, oxide powder less than 10 μm from Fe-77Ni alloy scrap was obtained using ball-milling and sieving processes and recovery ratio approached up to 97% for 15 hours.

  14. Development of processes for zircaloy chips recycling by electric arc furnace remelting and powder metallurgy; Desenvolvimento de processos de reciclagem de cavacos de zircaloy via refusao em forno eletrico a arco e metalurgia do po

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Luiz Alberto Tavares

    2014-09-01

    PWR reactors employ, as nuclear fuel, UO{sub 2} pellets with Zircaloy clad. In the fabrication of fuel element parts, machining chips from the alloys are generated. As the Zircaloy chips cannot be discarded as ordinary metallic waste, the recycling of this material is important for the Brazilian Nuclear Policy, which targets the reprocess of Zircaloy residues for economic and environmental aspects. This work presents two methods developed in order to recycle Zircaloy chips. In one of the methods, Zircaloy machining chips were refused using an electric-arc furnace to obtain small laboratory ingots. The second one uses powder metallurgy techniques, where the chips were submitted to hydriding process and the resulting material was milled, isostatically pressed and vacuum sintered. The ingots were heat-treated by vacuum annealing. The microstructures resulting from both processing methods were characterized using optical and scanning electron microscopy. Chemical composition, crystal phases and hardness were also determined. The results showed that the composition of recycled Zircaloy comply with the chemical specifications and presented adequate microstructure for nuclear use. The good results of the powder metallurgy method suggest the possibility of producing small parts, like cladding end-caps, using near net shape sintering. (author)

  15. Using economic benefits for recycling in a separate collection centre managed as a "reverse supermarket": a sociological survey.

    Science.gov (United States)

    De Feo, Giovanni; Polito, Anna Rita

    2015-04-01

    Separate collection centres (SCCs), where citizens can deliver recyclable fractions of municipal solid waste (MSW), in an "urban mining" perspective, can be considered a sort of "reverse supermarket", where people can deliver their recyclables in order to either obtain a waste fee reduction or shopping vouchers. The latter is the case of Baronissi, a town of around 17,000 inhabitants in the Province of Salerno, in the Campania region of Italy. The principal aim of the study was to investigate by means of a sociological survey the relationship between citizens and the separate collection program, with particular emphasis on the role played by the SCC. The separate collection system was evaluated either good or very good by 95.8% of the sample, while 99.2% expressed a good or very good evaluation of the quality of the service inside the separate collection centre: SCC users acted as a community as highlighted by the negative response of the Chi-square test for independence. Respecting the environment prevailed over saving time, obtaining eco-points, or saving money as the main reason why people went to the SCC. The majority of the respondents agreed if only putrescibles and residue should be collected directly from their homes, while all the other materials should be collected exclusively at the SCC, allowing to save money for the management of the kerbside collection system with a consequent further waste fee reduction for the residents.

  16. Comparative technoeconomic analysis of a softwood ethanol process featuring posthydrolysis sugars concentration operations and continuous fermentation with cell recycle.

    Science.gov (United States)

    Schneiderman, Steven J; Gurram, Raghu N; Menkhaus, Todd J; Gilcrease, Patrick C

    2015-01-01

    Economical production of second generation ethanol from Ponderosa pine is of interest due to widespread mountain pine beetle infestation in the western United States and Canada. The conversion process is limited by low glucose and high inhibitor concentrations resulting from conventional low-solids dilute acid pretreatment and enzymatic hydrolysis. Inhibited fermentations require larger fermentors (due to reduced volumetric productivity) and low sugars lead to low ethanol titers, increasing distillation costs. In this work, multiple effect evaporation (MEE) and nanofiltration (NF) were evaluated to concentrate the hydrolysate from 30 g/l to 100, 150, or 200 g/l glucose. To ferment this high gravity, inhibitor containing stream, traditional batch fermentation was compared with continuous stirred tank fermentation (CSTF) and continuous fermentation with cell recycle (CSTF-CR). Equivalent annual operating cost (EAOC = amortized capital + yearly operating expenses) was used to compare these potential improvements for a local-scale 5 MGY ethanol production facility. Hydrolysate concentration via evaporation increased EAOC over the base process due to the capital and energy intensive nature of evaporating a very dilute sugar stream; however, concentration via NF decreased EAOC for several of the cases (by 2 to 15%). NF concentration to 100 g/l glucose with a CSTF-CR was the most economical option, reducing EAOC by $0.15 per gallon ethanol produced. Sensitivity analyses on NF options showed that EAOC improvement over the base case could still be realized for even higher solids removal requirements (up to two times higher centrifuge requirement for the best case) or decreased NF performance.

  17. Urban mining : Recycling gypsum waste in Vancouver

    Energy Technology Data Exchange (ETDEWEB)

    McCamley, J.A. [New West Gypsum Recycling Inc., Vancouver, BC (Canada)

    2003-07-01

    Wallboard manufacturing, construction and deconstruction activities in North America, Europe and Japan result in large amounts of gypsum scrap, which creates an environmental problem. Disposing of this gypsum scrap in landfills often leads to hydrogen sulfide emissions and metallic sulfide groundwater leachates. Europe has dealt with the problem by enacting legislation that will come into effect in July 2005. The legislation is designed to strongly encourage gypsum recycling throughout entire jurisdictions. It is estimated that approximately 10 to 17 per cent of all gypsum used in the wallboard industry ends up as gypsum scrap. In North America, it represents almost one per cent of total waste. Each year in the United States, between 2.5 and 4.5 million tonnes of gypsum scrap are generated, with numbers very similar to Europe (the higher use of brick and concrete in Europe reduces the percentage of total tonnage). Gypsum has been banned from the landfills of British Columbia's Greater Vancouver region, forcing the recycling of all gypsum scrap. Large quantities of gypsum scrap are processed by New West Recycling, a Canadian firm using proprietary technology. This process leads to the re-incorporation of scrap gypsum into new wallboard, with the percentages sometimes reaching as high as 25 per cent. A case study of New West Recycling Inc., located in Langley, British Columbia was presented and recommendations were made concerning how other urban regions can implement gypsum scrap recycling programs modeled after this one. 6 refs.

  18. Scientific Opinion on the safety evaluation of the process “PRT (recoSTAR PET-FG” used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2012-12-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the recycling process PRT (recoSTAR PET-FG (EC register number RECYC050. The input of the process is washed and dried PET flakes originating from collected post-consumer PET bottles containing no more than 5% of PET from non-food consumer applications. Through the process, washed and dried PET flakes are heated and crystallised in a continuous first reactor under inert gas flow then heated in a second continuous reactor under inert gas flow before being extruded into pellets. After having examined the challenge test provided, the Panel concluded that the two steps, the drying and crystallisation (step 2 and the drying of the crystallised flakes (step 3 are the critical steps for the decontamination efficiency of the process. The operating parameters to control their performance are well defined and are the temperature, the gas flow and the residence time. The operating parameters of these steps in the process are at least as severe as those obtained from the challenge test. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore the Panel concluded that the recycled PET obtained from the process intended for the manufacture of materials and articles for contact with all types of foodstuffs for long term storage at room temperature, with or without hotfill is not considered of safety concern.

  19. Application of the Washing Waste Water Recycling Process Ultrafiltration Treatment Process%洗车废水循环利用过程中超滤处理工艺的应用探讨

    Institute of Scientific and Technical Information of China (English)

    刘昕

    2015-01-01

    The main subway train car wash waste water recycling process ultrafiltration treatment process applied technology were discussed, in order to promote recycling car wash industry, water resources, increase economic efficiency subway train car wash library.%主要对地铁列车洗车废水循环利用过程中的超滤处理工艺应用技术进行了探讨,以促进洗车行业水资源的循环利用,提高地铁列车洗车库的经济效益。

  20. Collection of Recyclables from Cubes

    DEFF Research Database (Denmark)

    Wøhlk, Sanne; Bogh, Morten Bie; Mikkelsen, Hardy

    2014-01-01

    Collection of recyclable materials is a major part of reverse logistics and an important issue in sustainable logistics. In this paper we consider a case study where paper and glass are collected from recycling cubes and transported to a treatment facility where it is processed for reuse. We...... situation for both the public company and the logistics provider....

  1. Study on Consumer Opposition to Exporting Recyclable Wastes

    Science.gov (United States)

    Suzuki, Yoshiyuki; Koizumi, Kunishige; Zhou, Weisheng

    Trans-boundary trade from Japan to China of recyclable wastes such as waste copper has increased rapidly, because of resource demands through economic growth. These wastes are recycled at high rates thanks to the Chinese manual recycling process by a lot of low wage migrant workers from rural districts. China benefits by supplying jobs to many migrant workers and getting cheap resources. Although, Japanese consumers may have some opposition to exporting end-of-pipe home appliance wastes to foreign countries. From the results of the path-analysis from the questionnaire to Japanese consumers, it became clear that their reluctance came from anxiety about illegal dumping, the labor environment at the import country and the destruction of the ecosystem. Through conjoint analysis, willingness to pay the recycling fee decreases - 1,625 yen (equal to 34% of the current recycling fee of 4,630 yen) when choosing global recycling as opposed to domestic recycling, hypothesizing that consumers would rather recycle domestically instead of globally.

  2. Waste paper for recycling: Overview and identification of potentially critical substances

    DEFF Research Database (Denmark)

    Pivnenko, Kostyantyn; Eriksson, Eva; Astrup, Thomas Fruergaard

    2015-01-01

    Paper product manufacturing involves a variety of chemicals used either directly in paper and pulp production or in the conversion processes (i.e. printing, gluing) that follow. Due to economic and environmental initiatives, paper recycling rates continue to rise. In Europe, recycling has increas...... substances were identified as potentially critical (selected mineral oils, phthalates, phenols, parabens, as well as other groups of chemicals) in relation to paper recycling. It is recommended that these substances receive more attention in waste paper....

  3. EVALUATION AND APPLICATION OF THE INVASIVE WEED MIKANIA MICRANTHA AS AN ALTERNATIVE REINFORCEMENT IN RECYCLED HIGH DENSITY POLYETHYLENE

    Directory of Open Access Journals (Sweden)

    Yong-Long Chen,

    2012-04-01

    Full Text Available In this study Mikania micrantha particle (MP and fiber (MF were added to recycled high density polyethylene (rHDPE for producing natural fiber (or particle reinforced plastic composites (NFRPC by the flat-platen pressing process. The results showed that the flexural strength and stiffness of NFRPC were significantly improved through incorporating M. micrantha particle and fiber. Higher aspect ratio of reinforcement displayed stronger mechanical properties. The vertical density profile in composites significantly influenced the mechanical properties of NFRPC. A conventional V-shaped profile and a uniform vertical density profile (homo-profile were observed in MP and MF based NFRPC, respectively. Additionally, with increasing lignocellulose content, a more uniform vertical density profile and higher wood screw holding strength were observed. These results indicate M. micrantha particle and fiber are excellent reinforcements for NFRPC applications.

  4. Scientific Opinion on the safety assessment of the process FOOD RePET FGI. H., used to recycle post-consumer PET into food contact materials

    OpenAIRE

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF)

    2014-01-01

    This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the recycling process FOOD RePET FGI. H., EU register No RECYC106. The input of the process is hot washed and dried PET flakes originating from collected post-consumer PET bottles containing no more than 5 % of PET from non-food consumer applications. In this process, washed and dried flakes are fed into a reactor at high temperature, crystallised, ...

  5. Characterization of DWPF recycle condensate materials

    Energy Technology Data Exchange (ETDEWEB)

    Bannochie, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Adamson, D. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); King, W. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-04-01

    A Defense Waste Processing Facility (DWPF) Recycle Condensate Tank (RCT) sample was delivered to the Savannah River National Laboratory (SRNL) for characterization with particular interest in the concentration of I-129, U-233, U-235, total U, and total Pu. Since a portion of Salt Batch 8 will contain DWPF recycle materials, the concentration of I-129 is important to understand for salt batch planning purposes. The chemical and physical characterizations are also needed as input to the interpretation of future work aimed at determining the propensity of the RCT material to foam, and methods to remediate any foaming potential. According to DWPF the Tank Farm 2H evaporator has experienced foaming while processing DWPF recycle materials. The characterization work on the RCT samples has been completed and is reported here.

  6. Use of scalp hair as indicator of human exposure to heavy metals in an electronic waste recycling area.

    Science.gov (United States)

    Wang, Thanh; Fu, Jianjie; Wang, Yawei; Liao, Chunyang; Tao, Yongqing; Jiang, Guibin

    2009-01-01

    Scalp hair samples were collected at an electronic waste (e-waste) recycling area and analyzed for trace elements and heavy metals. Elevated levels were found for Cu and Pb with geometric means (GMs) at 39.8 and 49.5 microg/g, and the levels of all elements were found in the rank order Pb > Cu > Mn > Ba > Cr > Ni > Cd > As > V. Besides Cu and Pb, Cd (GM: 0.518 microg/g) was also found to be significantly higher compared to that in hair samples from control areas. Differences with age, gender, residence status and villages could be distinguished for most of the elements. The high levels of Cd, Cu and Pb were likely found to be originated from e-waste related activities, and specific sources were discussed. This study shows that human scalp hair could be a useful biomarker to assess the extent of heavy metal exposure to workers and residents in areas with intensive e-waste recycling activities.

  7. Recycling of Paper and Cardboard

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Damgaard, Anders

    2011-01-01

    Paper and cardboard are produced from pulp derived from plant fibers, primarily wood. Paper and cardboard is used for many different products, such as for packaging material, newsprint and advertisements. Most of these products have very short lifetimes and thus constitute a major fraction of most...... and cardboard are produced and how waste paper is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of paper recycling....

  8. Carrageenan-grafted magnetite nanoparticles as recyclable sorbents for dye removal

    Energy Technology Data Exchange (ETDEWEB)

    Daniel-da-Silva, Ana L., E-mail: ana.luisa@ua.pt; Salgueiro, Ana M., E-mail: a38242@ua.pt; Creaney, Bianca, E-mail: bianca.creaney@gmail.com; Oliveira-Silva, Rui, E-mail: ruipedro.silva@ua.pt [University of Aveiro, Department of Chemistry, CICECO, Aveiro Institute of Materials (Portugal); Silva, Nuno J. O., E-mail: nunojoao@ua.pt [University of Aveiro, Department of Physics, CICECO, Aveiro Institute of Materials (Portugal); Trindade, Tito, E-mail: tito@ua.pt [University of Aveiro, Department of Chemistry, CICECO, Aveiro Institute of Materials (Portugal)

    2015-07-15

    The efforts dedicated to improving water decontamination procedures have prompted the interest in the development of efficient, inexpensive, and reusable sorbents for the uptake of dye pollutants. In this work, novel sorbents consisting of carrageenan polysaccharides grafted to magnetic iron oxide nanoparticles were prepared. κ- and ι-carrageenan were first chemically modified by carboxymethylation and then covalently attached via amide bond to the surface of aminated silica-coated magnetite nanoparticles, both steps monitored using infrared spectroscopy (FTIR) analysis. The kinetics and the equilibrium behavior of the cationic dye methylene blue (MB) adsorption onto the carrageenan sorbents were investigated. ι-carrageenan sorbents displayed higher MB adsorption capacity that was ascribed to high content of sulfonate groups. Overall, the pseudo-second order equation provided a good description of the adsorption kinetics. The κ-carrageenan sorbents followed an unusual Z-type equilibrium adsorption isotherm whereas the isotherm of ι-carrageenan sorbents, although displaying a conventional shape, could not be successfully predicted by isotherm models commonly used. Noteworthy, both sorbents were long-term stable and could easily be recycled by simply rinsing with KCl aqueous solution. The removal efficiency of κ-carrageenan sorbents was 92 % in the first adsorption cycle and kept high (>80 %) even after six consecutive adsorption/desorption cycles.

  9. Reactive Distillation and Air Stripping Processes for Water Recycling and Trace Contaminant Control

    Science.gov (United States)

    Boul, Peter J.; Lange, Kevin E.; Conger, Bruce; Anderson, Molly

    2009-01-01

    Reactive distillation designs are considered to reduce the presence of volatile organic compounds in the purified water. Reactive distillation integrates a reactor with a distillation column. A review of the literature in this field has revealed a variety of functional reactive columns in industry. Wastewater may be purified by a combination of a reactor and a distiller (e.g., the EWRS or VPCAR concepts) or, in principle, through a design which integrates the reactor with the distiller. A review of the literature in reactive distillation has identified some different designs in such combinations of reactor and distiller. An evaluation of reactive distillation and reactive air stripping is presented with regards to the reduction of volatile organic compounds in the contaminated water and air. Among the methods presented, an architecture is presented for the evaluation of the simultaneous oxidation of organics in air and water. These and other designs are presented in light of potential improvements in power consumptions and air and water purities for architectures which include catalytic activity integrated into the water processor. In particular, catalytic oxidation of organics may be useful as a tool to remove contaminants that more traditional distillation and/or air stripping columns may not remove. A review of the current leading edge at the commercial level and at the research frontier in catalytically active materials is presented. Themes and directions from the engineering developments in catalyst design are presented conceptually in light of developments in the nanoscale chemistry of a variety of catalyst materials.

  10. Scientific Opinion on the safety evaluation of the following processes based on BUHLER C technology used to recycle post-consumer PET into food contact materials “Buhler C” and “FENC”

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2012-12-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the recycling processes ‘’Buhler C’’ and “FENC’’ (EC register numbers RECYC037 and RECYC083 respectively which are based on the same BUHLER C technology. The decontamination efficiency of these processes was demonstrated using the same challenge tests. The input of the BUHLER C technology is washed and dried PET flakes originating from collected post-consumer PET containers containing no more than 5% of PET from non-food consumer applications. Through this technology, washed and dried flakes are dried and extruded in a ring extruder into pellets which are further crystallised in a reactor then fed into the Solid State Polymerisation (SSP reactor. After having examined the challenge tests provided, the Panel concluded that the two steps, the drying and crystallisation step and the SSP step are the most critical steps that determine the decontamination efficiency of the processes. The operating parameters to control the performance of these critical steps are well defined and are the temperature and the residence time for the drying and crystallisation, and the temperature, the gas flow and the residence time for SSP. The operating parameters of these steps in the processes are at least as severe as those obtained from the challenge tests. Under these conditions, it was demonstrated that the recycling processes are able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1μg/kg food. Therefore the Panel concluded that the recycled PET obtained from these processes intended for the manufacture of materials and articles for contact with all types of foodstuffs for long term storage at room temperature, with or without hotfill is not considered of safety concern.

  11. Regulation and government programs from a Canadian recyclers perspective

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, L.G. [Canadian Association of Recycling Industries, Almonte, ON (Canada)

    2000-07-01

    The environmental benefits of recycling were described. Recycling was defined as taking products at the end of their useful lives and then sorting and processing them to produce a secondary source of materials that can be used in the production of new goods. Recycling results in energy savings, creates jobs and reduces the demand for larger or more landfills. The author discussed many pros and cons regarding recycling in the following areas of concern: (1) the dumping of hazardous wastes by developed nations on developing nations, (2) the charging of disposal fees for waste, (3) taxing products made from recycled materials, (4) the use of air bags in automobiles, (5) the release of CFC from refrigerators, (6) blue box recycling programs, and (7) waste management at industrial parks. The actual response by various governments to these issues were also described. It was emphasized that often laws and regulations designed to control waste management when applied to recycling do not actually produce environmental improvements. Finally, new approaches with environmental solutions to some of the dilemmas associated with recycling were presented. 1 tab.

  12. Schizophrenia as a human process.

    Science.gov (United States)

    Corradi, Richard B

    2011-01-01

    The patient with schizophrenia often appears to be living in an alien world, one of strange voices, bizarre beliefs, and disorganized speech and behavior. It is difficult to empathize with someone suffering from symptoms so remote from one's ordinary experience. However, examination of the disorder reveals not only symptoms of the psychosis itself but also an intensely human struggle against the disintegration of personality it can produce. Furthermore, examination of the individual's attempts to cope with a devastating psychotic process reveals familiar psychodynamic processes and defense mechanisms, however unsuccessful they may be. Knowing that behind the seemingly alien diagnostic features of schizophrenia is a person attempting to preserve his or her self-identity puts a human face on the illness. This article utilizes clinical material to describe some of the psychodynamic processes of schizophrenia. Its purpose is to facilitate understanding of an illness that requires comprehensive biopsychosocial treatment in which a therapeutic doctor-patient relationship is as necessary as antipsychotic medication.

  13. Scientific Opinion on the safety assessment of the process LPR based on EREMA Advanced and Colortronic SSP ® technology used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2014-02-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the recycling process LPR (EU register No RECYC061 which is based on the EREMA advanced and Colortronic SSP ® technologies. The input to the process is hot caustic washed and dried PET flakes originating from collected post-consumer PET bottles and containing no more than 5 % of PET from non-food consumer applications. In this process, washed and dried PET flakes are heated successively in two continuous reactors under vacuum before being extruded into pellets. After extrusion they are crystallised and solid state polymerized. Having examined the results of the challenge test provided, the Panel concluded that the four steps, the decontamination in two continuous reactors, extrusion, crystallisation and solid state polymerization are the critical steps that determine the decontamination efficiency of the process. The operating parameters to control the performance of these critical steps are temperature, pressure, gas flow and residence time. Under these conditions, it was demonstrated that the recycling process is able to ensure that the level of migration of potential unknown contaminants into food is below the modelled migration of 0.1 μg/kg food derived from exposure scenario for infants and 0.15 μg/kg food derived from the exposure scenario for toddlers. The Panel concluded that recycled PET obtained from LPR process is not of safety concern when used to manufacture articles intended for food contact materials applications in compliance with the conditions as specified in the conclusion of the opinion.

  14. Study on Industrial Waste Materials as Coal Gangue Recycle Fe Deoxidized with High Grade from Steel Slag%利用工业废渣煤矸石高温还原回收钢渣中Fe的研究

    Institute of Scientific and Technical Information of China (English)

    杨曜; 殷素红; 徐创霞; 毛海勇

    2015-01-01

    The steel slag contains 4% ~35% FeOx , ap-proximately 3% ~10% about Fe. More than 100 million tons steel slag is discharged every year. A large amount of Fe within slag has been loosed and without recycled. If we can deoxidize the FeOx and recycle Fe from steel slag, a large number of iron resources will be recycled and it has more significance than only improve cementitious activity of steel slag. This paper utilizes waste materials as adjusting material of coal gangue with deoxidi-zing ability, and chose hot stuffy technology processed high al-kalinity and low aluminum steel slag from Shaoguan Iron. In the lab, we melt samples in 1 500 ℃, deoxidize the FeOx and recy-cle Fe, and simulate water quenching process form slag struc-ture. Recycle the Fe from steel slag. The results show that: u-sing coal gangue and low-quality fly ash smelting steel slag de-oxidizing the FeOx and recycle Fe in high temperature is practica-ble. The Fe content with recycled iron from the sample of steel slag of Shaoguan Iron mixed with 25. 7% coal gangue is 82. 45%.%钢渣中含有4%~35%的FeOx ,换算为金属铁含量为3%~10%。我国每年钢渣排放量超过1亿t,大量的Fe随着钢渣流失而未得到回收利用。若能将这部分铁元素还原回收,能够回收到大量的铁资源,且比仅考虑提高钢渣胶凝活性将其用于建材行业的低附加值利用具有更重要的意义。本文利用工业废渣煤矸石作为还原材料,选取热焖工艺高碱度低铝质韶钢钢渣,在试验室1500℃下高温熔融还原回收Fe。研究结果表明:利用煤矸石熔融还原回收钢渣中的Fe是可行的,掺25.7%煤矸石试样还原回收粗铁的品位高达82.45%。

  15. Assessing changes on poly(ethylene terephthalate) properties after recycling: Mechanical recycling in laboratory versus postconsumer recycled material

    Energy Technology Data Exchange (ETDEWEB)

    López, María del Mar Castro, E-mail: quimcl02@udc.es [Grupo de Polímeros, Centro de Investigacións Tecnológicas (CIT), Departamento de Física, Escuela Universitaria Politécnica, Universidade de A Coruña, Campus de Ferrol, 15403 Ferrol (Spain); Ares Pernas, Ana Isabel, E-mail: aares@udc.es [Grupo de Polímeros, Centro de Investigacións Tecnológicas (CIT), Departamento de Física, Escuela Universitaria Politécnica, Universidade de A Coruña, Campus de Ferrol, 15403 Ferrol (Spain); Abad López, Ma José, E-mail: mjabad@udc.es [Grupo de Polímeros, Centro de Investigacións Tecnológicas (CIT), Departamento de Física, Escuela Universitaria Politécnica, Universidade de A Coruña, Campus de Ferrol, 15403 Ferrol (Spain); and others

    2014-10-15

    Keeping rheological, mechanical and thermal properties of virgin poly(ethylene terephthalate), PET, is necessary to assure the quality of second-market applications. A comparative study of these properties has been undertaken in virgin, mechanical recycled and commercial recycled PET samples. Viscoelastic characterization was carried out by rheological measurements. Mechanical properties were estimated by tensile and Charpy impact strength tests. Thermal properties and crystallinity were evaluated by differential scanning calorimetry and a deconvolution procedure was applied to study the population of the different crystals. Molecular conformational changes related to crystallinity values were studied by FTIR spectroscopy. Variations in average molecular weight were predicted from rheology. Besides, the presence-absence of linear and cyclic oligomeric species was measured by mass spectrometry techniques, as MALDI-TOF. Mechanical recycled PET undergoes a significant decline in rheological, mechanical and thermal properties upon increasing the number of reprocessing steps. This is due to the cleavage of the ester bonds with reduction in molar mass and raise in cyclic oligomeric species, in particular [GT{sub c}]{sub n} and [GT{sub c}]{sub n}-G type. Chain shortening plus enrichment in trans conformers favour the crystallization process which occurs earlier and faster with modification in crystal populations. Additional physicochemical steps are necessary to preserve the main benefits of PET. - Highlights: • Combination of multiple techniques to characterize the effects of recycling in PET. • Cleavage of ester bonds reduced viscosity, Mw, toughness in mechanical recycled PET. • Virgin, mechanical recycled and commercial recycled PET differ in crystal populations. • Cyclic oligomers [GT{sub c}]{sub n} and [GT{sub c}]{sub n}-G increase from the fourth extrusion cycle onwards.

  16. Sustainability issues in circuit board recycling

    DEFF Research Database (Denmark)

    Legarth, Jens Brøbech; Alting, Leo; Baldo, Gian Luca

    1995-01-01

    The resource recovery and environmental impact issues of printed circuit board recycling by secondary copper smelters are discussed. Guidelines concerning material selection for circuit board manufacture and concerning the recycling processes are given to enhance recovery efficiency and to lower...... the impacts on the external environment from recycling...

  17. Recycling of blast furnace sludge by briquetting with starch binder: Waste gas from thermal treatment utilizable as a fuel.

    Science.gov (United States)

    Drobíková, Klára; Plachá, Daniela; Motyka, Oldřich; Gabor, Roman; Kutláková, Kateřina Mamulová; Vallová, Silvie; Seidlerová, Jana

    2016-02-01

    Steel plants generate significant amounts of wastes such as sludge, slag, and dust. Blast furnace sludge is a fine-grained waste characterized as hazardous and affecting the environment negatively. Briquetting is one of the possible ways of recycling of this waste while the formed briquettes serve as a feed material to the blast furnace. Several binders, both organic and inorganic, had been assessed, however, only the solid product had been analysed. The aim of this study was to assess the possibilities of briquetting using commonly available laundry starch as a binder while evaluating the possible utilization of the waste gas originating from the thermal treatment of the briquettes. Briquettes (100g) were formed with the admixture of starch (UNIPRET) and their mechanical properties were analysed. Consequently, they were subjected to thermal treatment of 900, 1000 and 1100°C with retention period of 40min during which was the waste gas collected and its content analysed using gas chromatography. Dependency of the concentration of the compounds forming the waste gas on the temperature used was determined using Principal component analysis (PCA) and correlation matrix. Starch was found to be a very good binder and reduction agent, it was confirmed that metallic iron was formed during the thermal treatment. Approximately 20l of waste gas was obtained from the treatment of one briquette; main compounds were methane and hydrogen rendering the waste gas utilizable as a fuel while the greatest yield was during the lowest temperatures. Preparation of blast furnace sludge briquettes using starch as a binder and their thermal treatment represents a suitable method for recycling of this type of metallurgical waste. Moreover, the composition of the resulting gas is favourable for its use as a fuel.

  18. Organization as Process of Communication

    DEFF Research Database (Denmark)

    Schoeneborn, Dennis; Vasquez, Consuelo; Cornelissen, Joep

    or metonymies. Unlike metaphors, which involve a horizontal comparison between two concepts or terms from domains that are – at least initially – seen as distant from one another, metonymies rely upon a vertical exchange between a whole and its parts within the same domain of language use. One prominent example...... of a metonymy is Morgan’s image of ‘organization as flux and transformation’ – an idea that has inspired a larger body of research that is known today asprocess organization studies”. In this paper we suggest to draw on the neighboring metonymic image ‘organization as communication’ which not only presents...

  19. Optimization of a microbial fuel cell for wastewater treatment using recycled scrap metals as a cost-effective cathode material.

    Science.gov (United States)

    Lefebvre, Olivier; Tan, Zi; Shen, Yujia; Ng, How Y

    2013-01-01

    Microbial fuel cell (MFC) for wastewater treatment is still hindered by the prohibitive cost of cathode material, especially when platinum is used to catalyze oxygen reduction. In this study, recycled scrap metals could be used efficiently as cathode material in a specially-designed MFC. In terms of raw power, the scrap metals ranked as follows: W/Co > Cu/Ni > Inconel 718 > carpenter alloy; however, in terms of cost and long term stability, Inconel 718 was the preferred choice. Treatment performance--assessed on real and synthetic wastewater--was considerably improved either by filling the anode compartment with carbon granules or by operating the MFC in full-loop mode. The latter option allowed reaching 99.7% acetate removal while generating a maximum power of 36 W m(-3) at an acetate concentration of 2535 mg L(-1). Under these conditions, the energy produced by the system averaged 0.1 kWh m(-3) of wastewater treated.

  20. A tale of five cities: Using recycling frameworks to analyse inclusive recycling performance.

    Science.gov (United States)

    Scheinberg, Anne; Simpson, Michael

    2015-11-01

    'Recycling' is a source of much confusion, particularly when comparing solid waste systems in high-income countries with those in low- and middle-income countries. Few analysts can explain why the performance and structure of recycling appears to be so different in rich countries from poor ones, nor why well-meaning efforts to implement recycling so often fail. The analysis of policy drivers, and the Integrated Sustainable Waste Management (ISWM) framework, come close to an explanation.This article builds on these earlier works, focusing in on five cities profiled in the 2010 UN-Habitat publication (Scheinberg A, Wilson DC and Rodic L (2010) Solid Waste Management in the World's Cities. UN-Habitat's Third Global Report on the State of Water and Sanitation in the World's Cities. Newcastle-on-Tyne, UK: Earthscan Publications). Data from these cities and others provides the basis for developing a new tool to analyse inclusive recycling performance. The points of departure are the institutional and economic relationships between the service chain, the public obligation to remove waste, pollution, and other forms of disvalue, and the value chain, a system of private enterprises trading valuable materials and providing markets for recyclables. The methodological innovation is to use flows of materials and money as indicators of institutional relationships, and is an extension of process flow diagramming.The authors are using the term 'recycling framework analysis' to describe this new form of institutional analysis. The diagrams increase our understanding of the factors that contribute to high-performance inclusive recycling. By focusing on institutional relationships, the article seeks to improve analysis, planning, and ultimately, outcomes, of recycling interventions.

  1. Life cycle perspective of plastic recycling

    Energy Technology Data Exchange (ETDEWEB)

    Ballhorn, R. [Targeted Research on Waste Minimization and Recycling Project, Darmstadt (Germany)

    2001-07-01

    Some recent European Union directives on recycling plastics are discussed, with particular reference to the automobile industry, highlighting developing chemical technologies such as selective solution/precipitation approaches, to increase the fraction of high quality recyclates. Some promising technologies, including separation by tribo-electrical charging, sorting by optical means, separation by gasification, dissolution, hydrogenation and co-processing with heavy oil residues are described, with examples involving the conversion of mixed plastic waste by gasification, and the production of PA6 monomer from carpet waste. Conclusion based on study results to date indicate that with regard to 'end of life' vehicles the driving force for dismantling is the recovery of resalable parts and metal, not plastic. Technologies for dismantling are seen as relatively crude. Moreover, the large investment required to construct a full dismantling facility and the lack of a well-developed 'after market' for recycled products makes it unlikely that such a facility will be built in the near future. The most promising way to cope with the economic and ecological challenges appears to be a combination of chemical recycling and energy recovery, accompanied by an aggressive effort to develop the 'after market' for the recycled products. 5 refs., 9 figs.

  2. Repairable Woven Carbon Fiber Composites with Full Recyclability Enabled by Malleable Polyimine Networks.

    Science.gov (United States)

    Taynton, Philip; Ni, Huagang; Zhu, Chengpu; Yu, Kai; Loob, Samuel; Jin, Yinghua; Qi, H Jerry; Zhang, Wei

    2016-04-20

    Carbon-fiber reinforced composites are prepared using catalyst-free malleable polyimine networks as binders. An energy neutral closed-loop recycling process has been developed, enabling recovery of 100% of the imine components and carbon fibers in their original form. Polyimine films made using >21% recycled content exhibit no loss of mechanical performance, therefore indicating all of the thermoset composite material can be recycled and reused for the same purpose.

  3. Energy efficiency of material and energy recycling, sustainability of different recycling methods; Energieeffizienz der stofflichen und energetischen Verwertung ausgewaehlter Abfallfraktionen

    Energy Technology Data Exchange (ETDEWEB)

    Friecke, Klaus; Bahr, Tobias [Technische Univ. Braunschweig (Germany). Lehrstuhl Abfall- und Ressourcenwirtschaft; Bidlingmaier, Werner [Bauhaus-Universitaet Weimar (Germany). Professur Abfallwirtschaft; Turk, Thomas [Poeyry Environment GmbH, Witzenhausen (Germany). Abt. IGW

    2010-02-15

    The approach for the sustainable usage of natural resources should lead to improved resource efficiency at the same time as a decrease of the negative ecological consequences of resource usage. Following this approach, the instruments of waste management particularly the material recycling and the energy recycling are also to be subject to a critical examination. The material recycling of paper and cardboard as well as plastics and biowaste has clear advantages over energy recycling processes in the aspect of energy efficiency. From the view of resource resp. energy efficiency also the recovering rate of metals is higher when they are collected from raw waste than when they are recovered from slag. This applies particularly for the nonferrous. This applies particularly for the nonferrous metals. Coupled with this as a rule, the climate change effects are also to be classified as lower. Which consequences can be drawn from these facts? Material recycling must be intensified. For paper/cardboard, plastics, biowaste and metals its is apparent that material recycling can be massively increased through intensifying the separate collecting systems and making them more flexible, in conjunction with an intensive use of sorting technologies. Collection and sorting systems are to be coordinated with each other. The goal of the whole system must be the reaching of an optimum between covering rate which is as high as possible and a high quality of recyclable material. (orig.)

  4. Utilize Cementitious High Carbon Fly Ash (CHCFA) to Stabilize Cold In-Place Recycled (CIR) Asphalt Pavement as Base Coarse

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Haifang; Li, Xiaojun; Edil, Tuncer; O' Donnell, Jonathan; Danda, Swapna

    2011-02-05

    The purpose of this study was to evaluate the performance of cementitious high carbon fly ash (CHCFA) stabilized recycled asphalt pavement as a base course material in a real world setting. Three test road cells were built at MnROAD facility in Minnesota. These cells have the same asphalt surface layers, subbases, and subgrades, but three different base courses: conventional crushed aggregates, untreated recycled pavement materials (RPM), and CHCFA stabilized RPM materials. During and after the construction of the three cells, laboratory and field tests were carried out to characterize the material properties. The test results were used in the mechanistic-empirical pavement design guide (MEPDG) to predict the pavement performance. Based on the performance prediction, the life cycle analyses of cost, energy consumption, and greenhouse gasses were performed. The leaching impacts of these three types of base materials were compared. The laboratory and field tests showed that fly ash stabilized RPM had higher modulus than crushed aggregate and RPM did. Based on the MEPDG performance prediction, the service life of the Cell 79 containing fly ash stabilized RPM, is 23.5 years, which is about twice the service life (11 years) of the Cell 77 with RPM base, and about three times the service life (7.5 years) of the Cell 78 with crushed aggregate base. The life cycle analysis indicated that the usage of the fly ash stabilized RPM as the base of the flexible pavement can significantly reduce the life cycle cost, the energy consumption, the greenhouse gases emission. Concentrations of many trace elements, particularly those with relatively low water quality standards, diminish over time as water flows through the pavement profile. For many elements, concentrations below US water drinking water quality standards are attained at the bottom of the pavement profile within 2-4 pore volumes of flow.

  5. Effect of recycling blast furnace flue dust as pellets on the sintering performance

    Directory of Open Access Journals (Sweden)

    El-Hussiny N.A.

    2010-01-01

    Full Text Available The Egyptian Iron and Steel Company generates a great amount of blast furnace flue dust. The recovery of metals and carbon from this flue dust becomes a very important demand due to the increase of the price of coke breeze and the decrease of the primary source of metals. At the same time, it make the environment more safe by decreasing pollution. Introducing these dust fines in the sintering process proves to be very harmful for different operating parameters. Thus, this study aims at investigating the production of pellets resulting from these fines, using molasses as organic binder and its application in sintering of iron ore. The sintering experiments were performed using flue dust as pellets as a substitute of coke breeze. The results revealed that, sintering properties such as inter strength increases with using the flue dust pellets, while productivity of both the sinter machine and sinter machine at blast furnace yard decreases. Also the vertical velocity of the sinter machine and the weight loss during the reduction of produced the sinter by hydrogen decrease.

  6. Polymer shell as a protective layer for the sandwiched gold nanoparticles and their recyclable catalytic property.

    Science.gov (United States)

    Liu, Bin; Wang, Xiaoman; Zhao, Yanwei; Wang, Jianchao; Yang, Xinlin

    2013-04-01

    Poly(ethyleneglycol methacrylate) (PEGDMA) shell was used as a protective layer for the sandwiched gold nanoparticles, which were prepared through the in situ reduction in the HAuCl4 precursor in the presence of (aminopropyl)trimethoxysilane (APS) modified silica/PEGDMA core-shell microspheres. In this process, the silica/PEGDMA core-shell microspheres were afforded by the distillation-precipitation polymerization of the EGDMA monomer on the APS-modified silica particles with the aid of hydrogen-bonding interaction. The gold nanoparticles were formed at the interface between the silica core and the PEGDMA outer layer through the strong coordinate interaction between the gold nanoparticles and the amino groups on the surface of the silica during the reduction in HAuCl4. The sandwiched gold nanoparticles exhibited highly catalytic efficiency and facile recovery with good stability.

  7. Reciclagem de fios e cabos elétricos - cabo paralelo Recycling of parallel wires using unit operations of mineral processing

    Directory of Open Access Journals (Sweden)

    Mishene Christie Pinheiro Bezerra de Araújo

    2008-09-01

    Full Text Available O descarte de produtos eletro-eletrônicos vem crescendo anualmente. Por esse motivo, necessita-se de reciclagem para que se evite o desperdício de recursos naturais não-renováveis. O objetivo desse trabalho é estudar a reciclagem dos cabos tipo cordão paralelo através de operações unitárias de tratamento de minérios. As seguintes operações unitárias foram testadas: moagem, separação granulométrica, separação em meio denso, separação eletrostática, atrição, bateamento e elutriação. Ao final desses processos, observou-se que as operações utilizadas obtiveram concentrados de cobre com baixo grau de contaminação. Observou-se que todas as técnicas precisam de uma outra técnica para complementá-las. Concluiu-se, ainda, que a moagem em moinho de facas com grelha de 3mm é necessária para se conseguir a total liberação dos materiais.The composition and discharge of eletro-electronic products is increasing year after year. To avoid the loss of non-renewable mineral resources and energy, the establishment of a recycling loop for such products is necessary. The goal of this work is to study the recycling of parallel wires using unit operations of mineral processing. The following unit operations were used: grinding, size separation, sink-and-float, electrostatic separation, scrubbing, panning and elutriation. One can observe a low contamination grade in the obtained copper. However, in all cases, a two step flow sheet must be used to completely separate plastics from copper. One can conclude that the total liberation of materials during grinding was reached when the final particle sizes were inferior to 3mm.

  8. Scientific Opinion on the safety assessment of the process “ILPA”, based on Starlinger Decon technology, used to recycle post-consumer PET into food contact materials

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2014-04-01

    Full Text Available This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety assessment of the recycling process ILPA (EU register No RECYC105 which is based on the Starlinger Decon technology. The input of the process is hot caustic washed and dried PET flakes originating from collected post-consumer PET containers, mainly bottles and trays, containing no more than 5 % of PET from non-food consumer applications. Through this technology washed and dried PET flakes are pre-heated before being solid state polymerised (SSP in a continuous reactor at high temperature under vacuum and gas flow. Having examined the challenge test provided, the Panel concluded that the pre-heating (step 2 and the decontamination in the continuous SSP reactor (step 3 are the critical steps that determine the decontamination efficiency of the process. The operating parameters to control their performance are well defined and are the temperature, the pressure, the residence time and the gas flow for step 2 and 3. Under these conditions, it was demonstated that the recycling process under evaluation, is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore, the recycled PET obtained from this process intended to be used up to 100 % for the manufacture of materials and articles for contact with all types of foodstuffs for long term storage at room temperature, with or without hotfill, is not considered of safety concern.

  9. Water recycle as a must: decolorization of textile wastewaters by plant-associated fungi.

    Science.gov (United States)

    Tegli, Stefania; Cerboneschi, Matteo; Corsi, Massimo; Bonnanni, Marco; Bianchini, Roberto

    2014-02-01

    Textile dye effluents are among the most problematic pollutants because of their toxicity on several organisms and ecosystems. Low cost and ecocompatible bioremediation processes offer a promising alternative to the conventional and aspecific physico-chemical procedures adopted so far. Here, microorganisms resident on three real textile dyeing effluent were isolated, characterized, and tested for their decolorizing performances. Although able to survive on these real textile-dyeing wastewaters, they always showed a very low decolorizing activity. On the contrary, several plant-associated fungi (Bjerkandera adusta, Funalia trogii, Irpex lacteus, Pleurotus ostreatus, Trametes hirsuta, Trichoderma viride, and Aspergillus nidulans) were also assayed and demonstrated to be able both to survive and to decolorize to various extents the three effluents, used as such in liquid cultures. The decolorizing potential of these fungi was demonstrated to be influenced by nutrient availability and pH. Best performances were constantly obtained using B. adusta and A. nidulans, relying on two strongly different mechanisms for their decolorizing activities: degradation for B. adusta and biosorption for A. nidulans. Acute toxicity tests using Daphnia magna showed a substantial reduction in toxicity of the three textile dyeing effluents when treated with B. adusta and A. nidulans, as suggested by mass spectrometric analysis as well.

  10. Scientific Opinion on the safety evaluation of the following processes based on Starlinger IV+ ® technology used to recycle post-consumer PET into food contact materials “Preformia, STF, MPTS, PET to PET and Eco Plastic”

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2012-08-01

    Full Text Available

    This scientific opinion of EFSA deals with the safety evaluation of the recycling processes Preformia, STF, MPTS, PET to PET and Eco Plastic (EC register numbers RECYC012, RECYC042, RECYC054, RECYC068 and RECYC080 respectively which are all based on the same STARLINGER IV+ ® technology. The decontamination efficiency of all these processes was demonstrated using the same challenge test. Through this technology, washed and dried post-consumer PET flakes are dried and crystallised in a reactor, then extruded under vacuum to provide pellets which are further crystallised in a second reactor. Crystallised pellets are then pre-heated in a third reactor and fed to the Solid State Polymerisation (SSP reactor. After having examined the challenge test provided, the Panel concluded that the three steps, drying and crystallisation, extrusion and crystallisation and SSP are the critical steps that determine the decontamination efficiency of the processes. The operating parameters to control the performance of these critical steps are the temperature, the gas flow and the residence time for the drying and crystallisation step, the temperature, the pressure and the residence time for extrusion and crystallisation and SSP steps. It was demonstrated by means of the challenge test that the recycling processes under evaluation using a Starlinger IV+ ® technology are able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.1 μg/kg food. Therefore  the Panel considered that the recycling processes Preformia, STF, MPTS, PET to PET and Eco Plastic are able to reduce any foreseeable accidental contamination of the post-consumer food contact PET to a concentration that does not give rise to concern for a risk to human health  if:

    1. they are operated under conditions that are at least as severe as those obtained from  the challenge test used to measure the

    2. Enzyme recycling in lignocellulosic biorefineries

      DEFF Research Database (Denmark)

      Jørgensen, Henning; Pinelo, Manuel

      2017-01-01

      platform. Cellulases are the most important enzymes required in this process, but the complex nature of lignocellulose requires several other enzymes (hemicellulases and auxiliary enzymes) for efficient hydrolysis. Enzyme recycling increases the catalytic productivity of the enzymes by reusing them...... upscaled and tested in industrial settings, mainly because of many difficulties with recycling of enzymes from the complex lignocellulose hydrolyzate at industrially relevant conditions, i.e., high solids loadings. The challenges are associated with the large number of different enzymes required...... for efficient hydrolysis, enzyme stability, and the detrimental interaction between enzyme and lignin. This review provides a comprehensive overview of the various methods for enzyme recovery and recycling, for example recycling of free enzymes, readsorption to fresh material, recycling of solids, membrane...

    3. Planning as an Iterative Process

      Science.gov (United States)

      Smith, David E.

      2012-01-01

      Activity planning for missions such as the Mars Exploration Rover mission presents many technical challenges, including oversubscription, consideration of time, concurrency, resources, preferences, and uncertainty. These challenges have all been addressed by the research community to varying degrees, but significant technical hurdles still remain. In addition, the integration of these capabilities into a single planning engine remains largely unaddressed. However, I argue that there is a deeper set of issues that needs to be considered namely the integration of planning into an iterative process that begins before the goals, objectives, and preferences are fully defined. This introduces a number of technical challenges for planning, including the ability to more naturally specify and utilize constraints on the planning process, the ability to generate multiple qualitatively different plans, and the ability to provide deep explanation of plans.

    4. In-Space Recycler Technology Demonstration

      Science.gov (United States)

      Hoyt, Rob; Werkheiser, NIKI; Kim, Tony

      2016-01-01

      In 2014, a 3D printer was installed and used successfully on the International Space Station (ISS), creating the first additively manufactured part in space. While additive manufacturing is a game changing technology for exploration missions, the process still requires raw feedstock material to fabricate parts. Without a recycling capability, a large supply of feedstock would need to be stored onboard, which negates the logistical benefits of these capabilities. Tethers Unlimited, Inc. (TUI), received a Small Business Innovation Research (SBIR) award to design and build the first In-space Recycler for demonstration aboard the ISS in 2017. To fully test this technology in microgravity, parts will be 3D printed, recycled into reusable filament, and then reprinted into new parts. Recycling scrap into printer filament is quite challenging in that a recycler must be able to handle a large variety of possible scrap configurations and densities. New challenges include: dealing with inevitable contamination of the scrap material, minimizing damage to the molecular structure of the plastic during reprocessing, managing a larger volume of hot liquid plastic, and exercising greater control over the cooling/resolidification of the material. TUI has developed an architecture that addresses these challenges by combining standard, proven technologies with novel, patented processes developed through this effort. Results show that the filament diameter achieved is more consistent than commercial filament, with only minimal degradation of material properties over recycling steps. In May 2016, TUI completed fabrication of a flight prototype, which will ultimately progress to the demonstration unit for the ISS as a testbed for future exploration missions. This capability will provide significant cost savings by reducing the launch mass and volume required for printer feedstock as well as reduce waste that must be stored or disposed.

    5. Recycling of Reinforced Plastics

      Science.gov (United States)

      Adams, R. D.; Collins, Andrew; Cooper, Duncan; Wingfield-Digby, Mark; Watts-Farmer, Archibald; Laurence, Anna; Patel, Kayur; Stevens, Mark; Watkins, Rhodri

      2014-02-01

      This work has shown is that it is possible to recycle continuous and short fibre reinforced thermosetting resins while keeping almost the whole of the original material, both fibres and matrix, within the recyclate. By splitting, crushing hot or cold, and hot forming, it is possible to create a recyclable material, which we designate a Remat, which can then be used to remanufacture other shapes, examples of plates and tubes being demonstrated. Not only can remanufacturing be done, but it has been shown that over 50 % of the original mechanical properties, such as the E modulus, tensile strength, and interlaminar shear strength, can be retained. Four different forms of composite were investigated, a random mat Glass Fibre Reinforced Plastic (GFRP) bathroom component and boat hull, woven glass and carbon fibre cloth impregnated with an epoxy resin, and unidirectional carbon fibre pre-preg. One of the main factors found to affect composite recyclability was the type of resin matrix used in the composite. Thermoset resins tested were shown to have a temperature range around the Glass Transition Temperature (Tg) where they exhibit ductile behaviour, hence aiding reforming of the material. The high-grade carbon fibre prepreg was found to be less easy to recycle than the woven of random fibre laminates. One method of remanufacturing was by heating the Remat to above its glass transition temperature, bending it to shape, and then cooling it. However, unless precautions are taken, the geometric form may revert. This does not happen with the crushed material.

    6. Challenges and Alternatives to Plastics Recycling in the Automotive Sector

      Directory of Open Access Journals (Sweden)

      Lindsay Miller

      2014-08-01

      Full Text Available Plastics are increasingly a preferred material choice in designing and developing complex, consumer products, such as automobiles, because they are mouldable, lightweight, and are often perceived to be highly recyclable materials. However, actually recycling the heterogeneous plastics used in such durable items is challenging, and presents very different scenarios to how simple products, such as water bottles, are recovered via curbside or container recycling initiatives. While the technology exists to recycle plastics, their feasibility to do so from high level consumer or industrial applications is bounded by technological and economical restraints. Obstacles include the lack of market for recyclates, and the lack of cost efficient recovery infrastructures or processes. Furthermore, there is a knowledge gap between manufacturers, consumers, and end-of-life facility operators. For these reasons, end-of-life plastics are more likely to end up down-cycled, or as shredder residue and then landfilled. This paper reviews these challenges and several alternatives to recycling plastics in order to broaden the mindset surrounding plastics recycling to improve their sustainability. The paper focuses on the automotive sector for examples, but discussion can be applied to a wide range of plastic components from similarly complex products.

    7. Waste material recycling: Assessment of contaminants limiting recycling

      DEFF Research Database (Denmark)

      Pivnenko, Kostyantyn

      systematically investigated. This PhD project provided detailed quantitative data following a consistent approach to assess potential limitations for the presence of chemicals in relation to material recycling. Paper and plastics were used as illustrative examples of materials with well-established recycling...... schemes and great potential for increase in recycling, respectively. The approach followed in the present work was developed and performed in four distinct steps. As step one, fractional composition of waste paper (30 fractions) and plastics (9 fractions) from households in Åbenrå municipality (Southern...... recycling has been recognised as a backbone of circular economy, with constant measures and initiatives being proposed in order to increase the recycling rates of materials being consumed. Material cycles are complex and dynamic systems where chemicals are added and removed in production, manufacturing...

    8. Recovering valuable metals from recycled photovoltaic modules.

      Science.gov (United States)

      Yi, Youn Kyu; Kim, Hyun Soo; Tran, Tam; Hong, Sung Kil; Kim, Myong Jun

      2014-07-01

      Recovering valuable metals such as Si, Ag, Cu, and Al has become a pressing issue as end-of-life photovoltaic modules need to be recycled in the near future to meet legislative requirements in most countries. Of major interest is the recovery and recycling of high-purity silicon (> 99.9%) for the production of wafers and semiconductors. The value of Si in crystalline-type photovoltaic modules is estimated to be -$95/kW at the 2012 metal price. At the current installed capacity of 30 GW/yr, the metal value in the PV modules represents valuable resources that should be recovered in the future. The recycling of end-of-life photovoltaic modules would supply > 88,000 and 207,000 tpa Si by 2040 and 2050, respectively. This represents more than 50% of the required Si for module fabrication. Experimental testwork on crystalline Si modules could recover a > 99.98%-grade Si product by HNO3/NaOH leaching to remove Al, Ag, and Ti and other metal ions from the doped Si. A further pyrometallurgical smelting at 1520 degrees C using CaO-CaF2-SiO2 slag mixture to scavenge the residual metals after acid leaching could finally produce > 99.998%-grade Si. A process based on HNO3/NaOH leaching and subsequent smelting is proposed for recycling Si from rejected or recycled photovoltaic modules. Implications: The photovoltaic industry is considering options of recycling PV modules to recover metals such as Si, Ag, Cu, Al, and others used in the manufacturing of the PV cells. This is to retain its "green" image and to comply with current legislations in several countries. An evaluation of potential resources made available from PV wastes and the technologies used for processing these materials is therefore of significant importance to the industry. Of interest are the costs of processing and the potential revenues gained from recycling, which should determine the viability of economic recycling of PV modules in the future.

    9. Determinants of an Environmental Horticulture Firm’s Recycle Process in terms of type and quantity: the Case of Georgia

      OpenAIRE

      Meng, Ting; Anna M., Klepacka; Florkowski, Wojciech; Kristine, Braman

      2015-01-01

      Environmental horticulture firms provide a variety of commercial/residential landscape products and services encompassing ornamental plant production, design, installation, and maintenance. The companies generate tons of waste including plastic containers, trays, and greenhouse/field covers, creating the need to reduce and utilize plastic waste. Based on survey data collected in Georgia in 2013, this paper investigates determinants of the environmental horticulture firms’ recycling decision (...

    10. Use of Recycling Building Demolition waste As Coarse Aggregate in Hot Mix Asphalt

      Directory of Open Access Journals (Sweden)

      Nabil I. Al- Sarrag* Hanaa Khaleel A Suham E. Saleh Al-Maliky

      2014-04-01

      Full Text Available At the recent years in Iraq, building demolition increase because of wars and the processes of destruction that lead to increase concrete waste, causing extreme pressure on the available land-filled sites that’s becomes a new challenge to local environment, in addition to south region from country poor from aggregate source.  So this study make as first evaluation to return use concrete aggregate for old and demolition building in concrete asphalt mix, the concrete aggregate obtained from building to live long more than 20 years after crash reinforcement concrete and sieving to get requirement granular particle to make locally asphalt mixture (Type IIIB depends on modified specification of State Commission of Roads and Bridges (2003 with percent (0,25,50,75,100% from weight of coarse aggregate.  Asphalt mixtures were tested by Marshall test, Indirect tensile strength test, and the loss of stability test.

    11. Recycling of Plastic

      DEFF Research Database (Denmark)

      Christensen, Thomas Højlund; Fruergaard, Thilde

      2011-01-01

      Plastic is produced from fossil oil. Plastic is used for many different products. Some plastic products like, for example, wrapping foil, bags and disposable containers for food and beverage have very short lifetimes and thus constitute a major fraction of most waste. Other plastic products like......, for example, gutters, window frames, car parts and transportation boxes have long lifetimes and thus appear as waste only many years after they have been introduced on the market. Plastic is constantly being used for new products because of its attractive material properties: relatively cheap, easy to form......, good strength and long durability. Recycling of plastic waste from production is well-established, while recycling of postconsumer plastic waste still is in its infancy. This chapter describes briefly how plastic is produced and how waste plastic is recycled in the industry. Quality requirements...

  1. Nutrient and media recycling in heterotrophic microalgae cultures.

    Science.gov (United States)

    Lowrey, Joshua; Armenta, Roberto E; Brooks, Marianne S

    2016-02-01

    In order for microalgae-based processes to reach commercial production for biofuels and high-value products such as omega-3 fatty acids, it is necessary that economic feasibility be demonstrated at the industrial scale. Therefore, process optimization is critical to ensure that the maximum yield can be achieved from the most efficient use of resources. This is particularly true for processes involving heterotrophic microalgae, which have not been studied as extensively as phototrophic microalgae. An area that has received significant conceptual praise, but little experimental validation, is that of nutrient recycling, where the waste materials from prior cultures and post-lipid extraction are reused for secondary fermentations. While the concept is very simple and could result in significant economic and environmental benefits, there are some underlying challenges that must be overcome before adoption of nutrient recycling is viable at commercial scale. Even more, adapting nutrient recycling for optimized heterotrophic cultures presents some added challenges that must be identified and addressed that have been largely unexplored to date. These challenges center on carbon and nitrogen recycling and the implications of using waste materials in conjunction with virgin nutrients for secondary cultures. The aim of this review is to provide a foundation for further understanding of nutrient recycling for microalgae cultivation. As such, we outline the current state of technology and practical challenges associated with nutrient recycling for heterotrophic microalgae on an industrial scale and give recommendations for future work.

  2. Stable isotope evidence for crustal recycling as recorded by superdeep diamonds

    OpenAIRE

    Burnham, A. D.; Thomson, A. R.; Bulanova, G. P.; Kohn, S. C.; Smith, C B; Walter, M. J.

    2015-01-01

    © 2015 Elsevier B.V. Sub-lithospheric diamonds from the Juina-5 and Collier-4 kimberlites and the Machado River alluvial deposit in Brazil have carbon isotopic compositions that co-vary with the oxygen isotopic compositions of their inclusions, which implies that they formed by a mixing process. The proposed model for this mixing process, based on interaction of slab-derived carbonate melt with reduced (carbide- or metal-bearing) ambient mantle, explains these isotopic observations. It is als...

  3. Mechanical recycling of waste electric and electronic equipment: a review.

    Science.gov (United States)

    Cui, Jirang; Forssberg, Eric

    2003-05-30

    The production of electric and electronic equipment (EEE) is one of the fastest growing areas. This development has resulted in an increase of waste electric and electronic equipment (WEEE). In view of the environmental problems involved in the management of WEEE, many counties and organizations have drafted national legislation to improve the reuse, recycling and other forms of recovery of such wastes so as to reduce disposal. Recycling of WEEE is an important subject not only from the point of waste treatment but also from the recovery of valuable materials.WEEE is diverse and complex, in terms of materials and components makeup as well as the original equipment's manufacturing processes. Characterization of this waste stream is of paramount importance for developing a cost-effective and environmentally friendly recycling system. In this paper, the physical and particle properties of WEEE are presented. Selective disassembly, targeting on singling out hazardous and/or valuable components, is an indispensable process in the practice of recycling of WEEE. Disassembly process planning and innovation of disassembly facilities are most active research areas. Mechanical/physical processing, based on the characterization of WEEE, provides an alternative means of recovering valuable materials. Mechanical processes, such as screening, shape separation, magnetic separation, Eddy current separation, electrostatic separation, and jigging have been widely utilized in recycling industry. However, recycling of WEEE is only beginning. For maximum separation of materials, WEEE should be shredded to small, even fine particles, generally below 5 or 10mm. Therefore, a discussion of mechanical separation processes for fine particles is highlighted in this paper. Consumer electronic equipment (brown goods), such as television sets, video recorders, are most common. It is very costly to perform manual dismantling of those products, due to the fact that brown goods contain very low

  4. Polystyrene-supported cu(II)-R-Box as recyclable catalyst in asymmetric Friedel–Crafts reaction

    KAUST Repository

    Desyatkin, V. G.

    2017-02-12

    The complex of copper(II) trifluoromethanesulfonate with chiral isopropyl bis(oxazoline) ligand (i-Pr-Box) was immobilized on accessible and inexpensive Merrifield resin according to a “click” procedure. The resulting catalyst showed high efficiency and recyclability in the asymmetric Friedel–Crafts alkylation of indole and its derivatives. The catalyst can be recycled five times without appreciable loss in activity and enantioselectivity.

  5. Ultrasound-assisted synthesis of β-amino ketones via a Mannich reaction catalyzed by Fe3O4 magnetite nanoparticles as an efficient, recyclable and heterogeneous catalyst

    Directory of Open Access Journals (Sweden)

    Naghi Saadatjoo

    2017-02-01

    The present methodology offers several advantages, such as good yields, short reaction times and a recyclable catalyst with a very easy work up. In addition, the obtained results indicated that MNPs can be used as an effective and inexpensive catalyst for stereoselective synthesis of β-amino carbonyl by a one-pot three component condensation of aldehydes, ketones and amines.

  6. Indole cyanation via C-H bond activation under catalysis of Ru(Ⅲ)-exchanged NaY zeolite (RuY) as a recyclable catalyst

    Institute of Scientific and Technical Information of China (English)

    Alireza Khorshidi

    2012-01-01

    Selective 3-cyanation of indoles was achieved under heterogeneous catalysis of Ru(Ⅲ)-exchanged NaY zeolite (RuY) as a recyclable catalyst,in combination with K4[Fe(CN)6] as a nontoxic,slow cyanide releasing agent.Under the aforementioned conditions,good yields of the desired products were obtained.

  7. Textile Recycling, Convenience, and the Older Adult.

    Science.gov (United States)

    Domina, Tanya; Koch, Kathryn

    2001-01-01

    Results of a study to examine the recycling practices and needs of older adults (n=217) indicated that older adults do recycle traditional materials, but need accommodations for physical limitations. They report textile recycling as time consuming and difficult and used donations to religious organizations as their principal means of textile…

  8. Recycling cobalt from spent lithium ion battery

    Institute of Scientific and Technical Information of China (English)

    Zhi-dong XIA; Xiao-qian XIE; Yao-wu SHI; Yong-ping LEI; Fu GUO

    2008-01-01

    Spent lithium ion battery is a useful resource of cobalt. In this paper, cobalt was recovered by a chemical process based upon the analysis of the structure and com-position of the lithium ion battery. X-ray diffraction results show that cobalt oxalate and cobaltous sulfate have been obtained in two different processes. Compared with the cobaltous oxalate process, the cobaltous sulfate process was characterized by less chemical substance input and a cobalt recovery rate of as much as 88%. A combination of these two processes in the recycling industry may win in the aspects of compact process and high recovery rate.

  9. Chemical solutions for greywater recycling.

    Science.gov (United States)

    Pidou, Marc; Avery, Lisa; Stephenson, Tom; Jeffrey, Paul; Parsons, Simon A; Liu, Shuming; Memon, Fayyaz A; Jefferson, Bruce

    2008-03-01

    Greywater recycling is now accepted as a sustainable solution to the general increase of the fresh water demand, water shortages and for environment protection. However, the majority of the suggested treatments are biological and such technologies can be affected, especially at small scale, by the variability in strength and flow of the greywater and potential shock loading. This investigation presents the study of alternative processes, coagulation and magnetic ion exchange resin, for the treatment of greywater for reuse. The potential of these processes as well as the influence of parameters such as coagulant or resin dose, pH or contact time were investigated for the treatment of two greywaters of low and high organic strengths. The results obtained revealed that magnetic ion exchange resin and coagulation were suitable treatment solutions for low strength greywater sources. However, they were unable to achieve the required level of treatment for the reuse of medium to high strength greywaters. Consequently, these processes could only be considered as an option for greywater recycling in specific conditions that is to say in case of low organic strength greywater or less stringent standards for reuse.

  10. APT铜钼渣回收工艺过程及环境影响分析%Environmental Impacts of APT Copper Molybdenum Slag Recycling Process

    Institute of Scientific and Technical Information of China (English)

    孙铭; 王嘉; 江英英; 杨林锋

    2012-01-01

    In addition to the introduction of molybdenum section of copper and molybdenum slag recycling business, raw materials, production processes, through a use of APT (ammonium paratungstate) quantitative analysis of waste gas, waste water, solid waste generation, proposed measures to mitigate the environmental impact. Copper and molybdenum slag recycling process of major air pollutants of S02 through the turbulent tower lye purification, can exhaust pollutants discharge standards; the production process of metal ions from wastewater by ion exchange column for recycling can be achieved wastewater discharge standards; all equipment noise to take the appropriate damping, noise reduction measures, the noise at boundary of the discharge standards; solid waste comprehensive utilization.%通过某利用APT(仲钨酸铵)除钼工段铜钼渣回收再利用企业的原料、生产工艺的介绍,定量地分析了废气、废水、固体废物的产生量,提出了减缓环境影响的措旅。铜钼渣回收利用过程产生的主要大气污染物是SO2,通过湍球塔碱液净化.可使废气污染物达标排放;生产过程产生的含金属离子废水通过离子交换柱进行回收利用,可做到废水达标排放;备设备噪声采取相应减震、减噪措施,厂界噪声可达标排放:固体废物可综合利用。

  11. Properties, Performance and Quality Control of Recycled MgO-C Bricks

    Institute of Scientific and Technical Information of China (English)

    TIAN Shouxin; YAO Jinfu; WANG Jing; YU Xingguo; YU Lingyan

    2008-01-01

    Properties, section structure and service results of recycled MgO-C bricks and new MgO-C bricks for la-dle slag line of Baosteel were analyzed and compared, and the measures of improving stability and quality of recycled MgO-C bricks were summarized. The results show that: ( 1 ) High quality recycled MgO - C materi-als can be produced by scientific, meticulous and strict management for every process such as dismantling fur-nace, selection, removing impurity and slag, stacking and homogenization; (2) Using high quality recycled materials and reasonable production technique, recycled MgO-C bricks with better properties and service efficien-cy than those of new MgO - C brick can be produced; (3) Service efficiency of recycled MgO-C bricks is good because of its high density, good oxidation resist-ance and reasonable structure.

  12. Speech parts as Poisson processes.

    Science.gov (United States)

    Badalamenti, A F

    2001-09-01

    This paper presents evidence that six of the seven parts of speech occur in written text as Poisson processes, simple or recurring. The six major parts are nouns, verbs, adjectives, adverbs, prepositions, and conjunctions, with the interjection occurring too infrequently to support a model. The data consist of more than the first 5000 words of works by four major authors coded to label the parts of speech, as well as periods (sentence terminators). Sentence length is measured via the period and found to be normally distributed with no stochastic model identified for its occurrence. The models for all six speech parts but the noun significantly distinguish some pairs of authors and likewise for the joint use of all words types. Any one author is significantly distinguished from any other by at least one word type and sentence length very significantly distinguishes each from all others. The variety of word type use, measured by Shannon entropy, builds to about 90% of its maximum possible value. The rate constants for nouns are close to the fractions of maximum entropy achieved. This finding together with the stochastic models and the relations among them suggest that the noun may be a primitive organizer of written text.

  13. EVALUATION OF THE IMPACT OF THE DEFENSE WASTE PROCESSING FACILITY (DWPF) LABORATORY GERMANIUM OXIDE USE ON RECYCLE TRANSFERS TO THE H-TANK FARM

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C.; Laurinat, J.

    2011-08-15

    When processing High Level Waste (HLW) glass, the Defense Waste Processing Facility (DWPF) cannot wait until the melt or waste glass has been made to assess its acceptability, since by then no further changes to the glass composition and acceptability are possible. Therefore, the acceptability decision is made on the upstream feed stream, rather than on the downstream melt or glass product. This strategy is known as 'feed forward statistical process control.' The DWPF depends on chemical analysis of the feed streams from the Sludge Receipt and Adjustment Tank (SRAT) and the Slurry Mix Evaporator (SME) where the frit plus adjusted sludge from the SRAT are mixed. The SME is the last vessel in which any chemical adjustments or frit additions can be made. Once the analyses of the SME product are deemed acceptable, the SME product is transferred to the Melter Feed Tank (MFT) and onto the melter. The SRAT and SME analyses have been analyzed by the DWPF laboratory using a 'Cold Chemical' method but this dissolution did not adequately dissolve all the elemental components. A new dissolution method which fuses the SRAT or SME product with cesium nitrate (CsNO{sub 3}), germanium (IV) oxide (GeO{sub 2}) and cesium carbonate (Cs{sub 2}CO{sub 3}) into a cesium germanate glass at 1050 C in platinum crucibles has been developed. Once the germanium glass is formed in that fusion, it is readily dissolved by concentrated nitric acid (about 1M) to solubilize all the elements in the SRAT and/or SME product for elemental analysis. When the chemical analyses are completed the acidic cesium-germanate solution is transferred from the DWPF analytic laboratory to the Recycle Collection Tank (RCT) where the pH is increased to {approx}12 M to be released back to the tank farm and the 2H evaporator. Therefore, about 2.5 kg/yr of GeO{sub 2}/year will be diluted into 1.4 million gallons of recycle. This 2.5 kg/yr of GeO{sub 2} may increase to 4 kg/yr when improvements are

  14. Stable isotope evidence for crustal recycling as recorded by superdeep diamonds

    Science.gov (United States)

    Burnham, A. D.; Thomson, A. R.; Bulanova, G. P.; Kohn, S. C.; Smith, C. B.; Walter, M. J.

    2015-12-01

    Sub-lithospheric diamonds from the Juina-5 and Collier-4 kimberlites and the Machado River alluvial deposit in Brazil have carbon isotopic compositions that co-vary with the oxygen isotopic compositions of their inclusions, which implies that they formed by a mixing process. The proposed model for this mixing process, based on interaction of slab-derived carbonate melt with reduced (carbide- or metal-bearing) ambient mantle, explains these isotopic observations. It is also consistent with the observed trace element chemistries of diamond inclusions from these localities and with the experimental phase relations of carbonated subducted crust. The 18O-enriched nature of the inclusions demonstrates that they incorporate material from crustal protoliths that previously interacted with seawater, thus confirming the subduction-related origin of superdeep diamonds. These samples also provide direct evidence of an isotopically anomalous reservoir in the deep (≥350 km) mantle.

  15. Thorium-U Recycle Facility (7930)

    Data.gov (United States)

    Federal Laboratory Consortium — The Thorium-U Recycle Facility (7930), along with the Transuranic Processing Facility (7920). comprise the Radiochemical Engineering Development Complex. 7930 is a...

  16. An environmentally benign three component one-pot synthesis of amidoalkyl naphthols using H4SiW12O40 as a recyclable catalyst

    Indian Academy of Sciences (India)

    Amit R Supale; Gavisiddappa S Gokavi

    2010-03-01

    One pot synthesis of amidoalkyl naphthol by condensation of aromatic aldehydes, 2-naphthol and amide/urea using silicotungstic acid as a catalyst is reported. The reaction was carried out under solvent-free reaction conditions. The method gave good yields of amidoalkyl naphthols in short reaction time compared with previous methods. The catalyst is recycled for five consecutive times without loss of activity.

  17. Solid waste recycling in Rajshahi city of Bangladesh.

    Science.gov (United States)

    Bari, Q Hamidul; Hassan, K Mahbub; Haque, M Ehsanul

    2012-11-01

    Efficient recycling of solid wastes is now a global concern for a sustainable and environmentally sound management. In this study, traditional recycling pattern of solid waste was investigated in Rajshahi municipality which is the fourth largest city of Bangladesh. A questionnaire survey had been carried out in various recycle shops during April 2010 to January 2011. There were 140 recycle shops and most of them were located in the vicinity of Stadium market in Rajshahi. About 1906 people were found to be involved in recycling activities of the city. The major fraction of recycled wastes were sent to capital city Dhaka for further manufacture of different new products. Only a small amount of wastes, specially plastics, were processed in local recycle factories to produce small washing pots and bottle caps. Everyday, an estimated 28.13 tons of recycled solid wastes were handled in Rajshahi city area. This recycled portion accounted for 8.25% of the daily total generated wastes (341 ton d(-1)), 54.6% of total recyclable wastes (51.49 ton d(-1)) and 68.29% of readily recyclable wastes (41.19 ton d(-1)). Major recycled materials were found to be iron, glass, plastic, and papers. Only five factories were involved in preliminary processing of recyclable wastes. Collecting and processing secondary materials, manufacturing recycled-content products, and then buying recycled products created a circle or loop that ensured the overall success of recycling and generated a host of financial, environmental, and social returns.

  18. Vehicle recycling regulations

    DEFF Research Database (Denmark)

    Smink, Carla

    2007-01-01

    The number of end-of-life vehicles (ELVs) in the EU is increasing continously. Around 75 percent of an ELV are recyclable metals. The forecast growth in the number of ELVs calls for regulation that aims to minimise the environmental impact of a car. Using Denmark as an example, this article...

  19. Nano-magnetite (Fe3O4) as a support for recyclable catalysts in the development of sustainable methodologies.

    Science.gov (United States)

    Gawande, Manoj B; Branco, Paula S; Varma, Rajender S

    2013-04-21

    Surface functionalization of nano-magnetic nanoparticles is a well-designed way to bridge the gap between heterogeneous and homogeneous catalysis. The introduction of magnetic nanoparticles (MNPs) in a variety of solid matrices allows the combination of well-known procedures for catalyst heterogenization with techniques for magnetic separation. Magnetite is a well-known material, also known as ferrite (Fe3O4), and can be used as a versatile support for functionalization of metals, organocatalysts, N-heterocyclic carbenes, and chiral catalysts. It is used as a support for important homogeneous catalytically active metals such as Pd, Pt, Cu, Ni, Co, Ir, etc. to obtain stable and magnetically recyclable heterogeneous catalysts. Homogeneous organocatalysts can be successfully decorated with linkers/ligands on the surface of magnetite or alternatively the organocatalysts can be directly immobilized on the surface of magnetite. The functionalized magnetically retrievable catalysts or nanocatalysts that are increasingly being used in catalysis, green chemistry and pharmaceutically significant reactions are summarized in this review.

  20. Poly(ethylene Terephthalate), Pet: A Review On The Synthesis Processes, Degradation Mechanisms And Its Recycling [poli(tereftalato De Etileno), Pet:uma Revisão Sobre Os Processos De íntese, Mecanismos De Egradação E Sua Reciclagem

    OpenAIRE

    Romao W.; Spinace M.A.S.; De Paoli M.-A.

    2009-01-01

    We present a review on poly(ethylene terephthalate), emphasizing the synthesis processes and the degradation mechanisms. Brazil is currently among the countries that most recycle PET, with 53% of this polymer being mechanically recycled. The success of this thermoplastic in the recycling industry is due to its large diversity of applications, from the textile industry to food packaging, where the food grade recycled packages will be mixed with the pristine resin for reprocessing and use. We a...

  1. Indicators for the feasibility of WEEE processing plants in brazil: a relationship between virgin mineral copper ore and the recycling of consumer electronic products

    Directory of Open Access Journals (Sweden)

    Luis Henrique Alves Cândido

    2015-07-01

    Full Text Available This paper assesses the economic analysis of the implementation of WEEE – Waste Electrical and Electronic Equipment Directive – processing plants in Brazil, through the study of potential copper extraction from this secondary source. A comparative approach was performed on its copper grade related to levels of its virgin ore mineral extracted from mines located in Brazil, in the United States and through a global average. The results demonstrate that the amount of copper mass originated from the recycling of disassembly of twenty electronic products ranges from 0.24% to 17.83% of its total mass, with an average of 3.63% of copper. In eighteen of these products, values greater than 0.4% were found, which surpass current levels of copper in ore mines in the USA. In fourteen products, these rates exceed the index of 1.5% copper in the ore, considered the minimum rate for the feasibility of opening new units of copper underground mining in Brazil. Thus, this paper shows the economic analysis that aims to guide on the viability of deploying WEEE processing plants, focusing on the expansion of recycling and reuse of copper by the processing industry.

  2. Recycled asphalt pavement - fly ash geopolymers as a sustainable pavement base material: Strength and toxic leaching investigations.

    Science.gov (United States)

    Hoy, Menglim; Horpibulsuk, Suksun; Rachan, Runglawan; Chinkulkijniwat, Avirut; Arulrajah, Arul

    2016-12-15

    In this research, a low-carbon stabilization method was studied using Recycled Asphalt Pavement (RAP) and Fly Ash (FA) geopolymers as a sustainable pavement material. The liquid alkaline activator (L) is a mixture of sodium silicate (Na2SiO3) and sodium hydroxide (NaOH), and high calcium FA is used as a precursor to synthesize the FA-RAP geopolymers. Unconfined Compressive Strength (UCS) of RAP-FA blend and RAP-FA geopolymer are investigated and compared with the requirement of the national road authorities of Thailand. The leachability of the heavy metals is measured by Toxicity Characteristic Leaching Procedure (TCLP) and compared with international standards. The Scanning Electron Microscopy (SEM) analysis of RAP-FA blend indicates the Calcium Aluminate (Silicate) Hydrate (C-A-S-H) formation, which is due to a reaction between the high calcium in RAP and high silica and alumina in FA. The low geopolymerization products (N-A-S-H) of RAP-FA geopolymer at NaOH/Na2SiO3=100:0 are detected at the early 7days of curing, hence its UCS is lower than that of RAP-FA blend. The 28-day UCS of RAP-FA geopolymers at various NaOH/Na2SiO3 ratios are significantly higher than that of the RAP-FA blend, which can be attributed to the development of geopolymerization reactions. With the input of Na2SiO3, the highly soluble silica from Na2SiO3 reacted with leached silica and alumina from FA and RAP and with free calcium from FA and RAP; hence the coexistence of N-A-S-H gel and C-A-S-H products. Therefore, the 7-day UCS values of RAP-FA geopolymers increase with decreasing NaOH/Na2SiO3 ratio. TCLP results demonstrated that there is no environmental risk for both RAP-FA blends and RAP-FA geopolymers in road construction. The geopolymer binder reduces the leaching of heavy metal in RAP-FA mixture. The outcomes from this research will promote the move toward increased applications of recycled materials in a sustainable manner in road construction.

  3. Recycling, Canadian update

    Energy Technology Data Exchange (ETDEWEB)

    Lakshmanan, V. I. [Process Research ORTECH Inc., Mississauga, ON (Canada); Shaw, L. [Canadian Association of Recycling Industries, Almonte, ON (Canada)

    2001-07-01

    An update on the recycling industry in Canada is provided by way of selected examples involving the recovery of gallium from electronic scrap, magnesium recovery from mine tailings and energy recovery from metal industry processes. These examples have been selected to illustrate the synergy between major mining, metallurgical and utility industries with end users in the building materials, automotive and electronic industries. 1 tab., 1 fig.

  4. Municipal solid waste recycling and the significance of informal sector in urban China.

    Science.gov (United States)

    Linzner, Roland; Salhofer, Stefan

    2014-09-01

    The informal sector is active in the collection, processing and trading of recyclable materials in urban China. Formal waste management organisations have established pilot schemes for source separation of recyclables, but this strategy is still in its infancy. The amounts of recyclables informally picked out of the municipal solid waste stream are unknown as informal waste workers do not record their activities. This article estimates the size and significance of the current informal recycling system with a focus on the collection of recyclables. A majority of the reviewed literature detects that official data is displaying mainly 'municipal solid waste collected and transported', whereas less information is available on 'real' waste generation rates at the source. Based on a literature review the variables, the 'number of informal waste workers involved in collection activities', the 'amounts collected daily per informal collector' and the 'number of working days' are used to estimate yearly recyclable amounts that are informally diverted from municipal solid waste. The results show an interval of approximately 0.56%-0.93% of the urban population or 3.3-5.6 million people involved in informal waste collection and recycling activities in urban China. This is the equivalent to estimated informal recycling rates of approximately 17-38 w/w% of the municipal solid waste generated. Despite some uncertainties in these assessments, it can be concluded that a significant share of recyclables is collected and processed by informal waste workers.

  5. Lactic acid production by Lactobacillus sp. RKY2 in a cell-recycle continuous fermentation using lignocellulosic hydrolyzates as inexpensive raw materials.

    Science.gov (United States)

    Wee, Young-Jung; Ryu, Hwa-Won

    2009-09-01

    Continuous lactic acid fermentations were conducted using lignocellulosic hydrolyzates and corn steep liquor as inexpensive raw materials. Lactic acid concentrations decreased with increases in the dilution rate, whereas the residual substrate concentrations increased. However, lactic acid yields were maintained at more than 0.90 g g(-1) over all cases experimented. The cell-recycle cultivation system exerted positive effects on fermentation efficiency, including volumetric productivity, which is attributable to the retention of cells in the bioreactor. The cell-recycle continuous fermentation of lignocellulosic hydrolyzates yielded a lactic acid productivity of 6.7 g l(-1) h(-1) for a dilution rate of 0.16 h(-1) using 30 g l(-1) of corn steep liquor and 1.5 g l(-1) of yeast extract as nutrients. The productivity (6.7 g l(-1) h(-1)) acquired by the cell-recycle continuous fermentation of lignocellulosic hydrolyzates was 1.6 times higher than the lactic acid productivity yielded in the continuous fermentation without cell-recycle system.

  6. Continuous Fermentation of Clostridium tyrobutyricum with Partial Cell Recycle as a Long-Term Strategy for Butyric Acid Production

    Directory of Open Access Journals (Sweden)

    Edgar C. Clausen

    2012-08-01

    Full Text Available In making alternative fuels from biomass feedstocks, the production of butyric acid is a key intermediate in the two-step production of butanol. The fermentation of glucose via Clostridium tyrobutyricum to butyric acid produces undesirable byproducts, including lactic acid and acetic acid, which significantly affect the butyric acid yield and productivity. This paper focuses on the production of butyric acid using Clostridium tyrobutyricum in a partial cell recycle mode to improve fermenter yield and productivity. Experiments with fermentation in batch, continuous culture and continuous culture with partial cell recycle by ultrafiltration were conducted. The results show that a continuous fermentation can be sustained for more than 120 days, which is the first reported long-term production of butyric acid in a continuous operation. Further, the results also show that partial cell recycle via membrane ultrafiltration has a great influence on the selectivity and productivity of butyric acid, with an increase in selectivity from ≈9% to 95% butyric acid with productivities as high as 1.13 g/Lh. Continuous fermentation with low dilution rate and high cell recycle ratio has been found to be desirable for optimum productivity and selectivity toward butyric acid and a comprehensive model explaining this phenomenon is given.

  7. Widespread tungsten isotope anomalies and W mobility in crustal and mantle rocks of the Eoarchean Saglek Block, northern Labrador, Canada: Implications for early Earth processes and W recycling

    Science.gov (United States)

    Liu, Jingao; Touboul, Mathieu; Ishikawa, Akira; Walker, Richard J.; Graham Pearson, D.

    2016-08-01

    Earth's mantle with regard to late accretionary processes. Although 182W anomalies can be erased via mixing in the convective mantle, recycling of 182W-rich crustal rocks into the mantle can produce new mantle sources with anomalous W isotopic compositions that can be tapped at much later times and, hence, this process should be considered as a mechanism for the generation of 182W-rich rocks at any subsequent time in Earth history.

  8. Mechanical recycling of continuous fiber-reinforced thermoplastic sheets

    Science.gov (United States)

    Moritzer, Elmar; Heiderich, Gilmar

    2016-03-01

    This contribution examines possible material recycling of offcuts generated during the production of continuous-fiber-reinforced composite sheets. These sheets consist of a polyamide 6 matrix and glass fiber fabric. In the initial step, the offcut is shredded to obtain particles; following that, the particles are processed in a twin-screw process to produce fiber-reinforced plastic pellets with varying fiber contents. These pellets are intended for use in injection molding processes as a substitution for new raw materials. This investigation centers on the mechanical properties which can be achieved with the recycled material after both the twin-screw process and injection molding.

  9. Transition metal (Fe, Co and Ni) oxide nanoparticles grafted graphitic carbon nitrides as efficient optical limiters and recyclable photocatalysts

    Science.gov (United States)

    Sridharan, Kishore; Kuriakose, Tintu; Philip, Reji; Park, Tae Joo

    2014-07-01

    A single-step pyrolysis assisted route towards the large scale fabrication of metal oxide nanoparticles (Fe2O3, Co3O4 and NiO) ingrained in graphitic carbon nitride (GCN) is demonstrated. Urea, an abundantly available precursor, plays a dual role during the synthesis: while it acts as a reducing agent, it also gets converted to GCN. The formation of GCN and the in-situ growth and embedment of oxide nanoparticles are discussed on the basis of the experimental results. The wide absorption of the samples in the visible light region makes them suitable for nonlinear transmission and photocatalytic activity studies. Visible light photocatalytic activities of the samples are studied by monitoring the degradation of Rhodamine B dye. Optical limiting properties of the prepared samples are studied through the open aperture z-scan technique using 5 ns laser pulses at a wavelength of 532 nm. The cost-efficient and time saving synthetic approach is complemented by the magnetic behaviour of the samples, which enables their use as recyclable photocatalyst and magnetically controllable optical limiters.

  10. The recycling of Mn-Zn ferrite wastes through a hydrometallurgical route

    Energy Technology Data Exchange (ETDEWEB)

    Li, Kangkang [School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China); Peng, Changhong, E-mail: phc416@csu.edu.cn [School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China); Jiang, Kaiqi [School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China)

    2011-10-30

    Highlights: {yields} Mn-Zn ferrite wastes were recycled through wet chemical route. {yields} The Mn-Zn ferrite takes advantage over A102 made in Acme Electronics Corporation. {yields} The novel recycling technology attained environmental, social and economic benefits. - Abstract: A novel recycling route using acid leaching, reduction, purification, co-precipitation and traditional ceramic process was applied to process the Mn-Zn ferrite wastes and prepare the corresponding high permeability soft magnetic product. Above 95% of Fe, Mn, Zn in the waste materials could be recycled in the form of Mn-Zn ferrite products through the hydrometallurgical route. The comprehensive properties of Mn-Zn ferrite prepared from wastes by this route have broader frequency characteristics, higher resistivity, lower loss coefficient and temperature coefficient as compared to the A102 product (Acme Electronics Corporation, Taiwan). Moreover, the cost of this recycling technology has economical advantage over the traditional ceramic process, which holds a promising industrial application.

  11. In(OTf)3 as a powerful and recyclable catalyst for Pechmann condensation without solvent

    Institute of Scientific and Technical Information of China (English)

    Bahador Karami; Mahtab Kiani; Mohsen Ahmad Hoseini

    2014-01-01

    In(OTf)3 plays the role of a Lewis acid catalyst in the Pechmann condensation of phenols with β-ketoesters under solvent-free conditions to give coumarin derivatives. This novel and inexpensive method has advantages such as short reaction time, excellent product yields, and avoids the use of organic solvents in agreement with green chemistry principles. Catalyst loadings can be as low as 1 mol% to give high yields of the corresponding coumarins at 80 °C. The catalyst can be recovered after the reaction, and reused with only a slight decrease in the yield.

  12. Cross-Linked ZnO Nanowalls Immobilized onto Bamboo Surface and Their Use as Recyclable Photocatalysts

    Directory of Open Access Journals (Sweden)

    Chunde Jin

    2014-01-01

    Full Text Available A novel recyclable photocatalyst was fabricated by hydrothermal method to immobilize the cross-linked ZnO nanowalls on the bamboo surface. The resultant samples were characterized by using scanning electron microscopy (SEM, X-ray diffraction (XRD, energy dispersive spectroscopy (EDS, and Fourier transformation infrared (FTIR techniques. FTIR spectra demonstrated that the cross-linked wurtzite ZnO nanowalls and bamboo surface were interconnected with each other by hydrogen bonds. Meanwhile, the cross-linked ZnO nanowalls modified bamboo (CZNB presented a superior photocatalytic ability and could be recycled at least 3 times with a photocatalytic efficiency up to 70%. The current research provides a new opportunity for the development of a portable and recycled biomass-based photocatalysts which can be an efficiently degraded pollutant solution and reused several times.

  13. Proceedings of waste stream minimization and utilization innovative concepts: An experimental technology exchange. Volume 1, Industrial solid waste processing municipal waste reduction/recycling

    Energy Technology Data Exchange (ETDEWEB)

    Lee, V.E. [ed.; Watts, R.L.

    1993-04-01

    This two-volume proceedings summarizes the results of fifteen innovations that were funded through the US Department of Energy`s Innovative Concept Program. The fifteen innovations were presented at the sixth Innovative Concepts Fair, held in Austin, Texas, on April 22--23, 1993. The concepts in this year`s fair address innovations that can substantially reduce or use waste streams. Each paper describes the need for the proposed concept, the concept being proposed, and the concept`s economics and market potential, key experimental results, and future development needs. The papers are divided into two volumes: Volume 1 addresses innovations for industrial solid waste processing and municipal waste reduction/recycling, and Volume 2 addresses industrial liquid waste processing and industrial gaseous waste processing. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  14. Recycling of residual IGCC slags and their benefits as degreasers in ceramics.

    Science.gov (United States)

    Iglesias Martín, I; Acosta Echeverría, A; García-Romero, E

    2013-11-15

    This work studies the evolution of IGCC slag grains within a ceramic matrix fired at different temperatures to investigate the effect of using IGCC slag as a degreaser. Pressed ceramic specimens from two clay mixtures are used in this study. The M1 mixture is composed of standard clays, whereas the M2 mixture is composed of the same clay mixture as M1 mixture but contains 15% by weight IGCC slag. The amount of IGCC slag added coincides with the amount of slag typically used as a degreaser in the ceramic industry. Specimens are fired at 950 °C, 1000 °C, 1050 °C, 1100 °C and 1150 °C. The mineralogical composition and the IGCC slag grain shape within the ceramic matrix are determined by X-ray diffraction, polarized light microscopy and scanning electron microscopy. The results reveal that the surface of the slag grains is welded to the ceramic matrix while the quartz grains are separated, which causes increased water absorption and reduces the mechanical strength. IGCC slag, however, reduces water absorption. This behaviour is due to the softening temperature of the slag. This property is quite important from an industrial viewpoint because IGCC slag can serve as an alternative to traditional degreasing agents in the ceramic building industry. Additionally, using IGCC slag allows for the transformation of waste into a secondary raw material, thereby avoiding disposal at landfills; moreover, these industrial wastes are made inert and improve the properties of ceramics.

  15. Utilization of recycled glass derived from cathode ray tube glass as fine aggregate in cement mortar.

    Science.gov (United States)

    Ling, Tung-Chai; Poon, Chi-Sun

    2011-08-30

    Rapid advances in the electronic industry led to an excessive amount of early disposal of older electronic devices such as computer monitors and old televisions (TV) before the end of their useful life. The management of cathode ray tubes (CRT), which have been a key component in computer monitors and TV sets, has become a major environmental problem worldwide. Therefore, there is a pressing need to develop sustainable alternative methods to manage hazardous CRT glass waste. This study assesses the feasibility of utilizing CRT glass as a substitute for natural aggregates in cement mortar. The CRT glass investigated was an acid-washed funnel glass of dismantled CRT from computer monitors and old TV sets. The mechanical properties of mortar mixes containing 0%, 25%, 50%, 75% and 100% of CRT glass were investigated. The potential of the alkali-silica reaction (ASR) and leachability of lead were also evaluated. The results confirmed that the properties of the mortar mixes prepared with CRT glass was similar to that of the control mortar using sand as fine aggregate, and displayed innocuous behaviour in the ASR expansion test. Incorporating CRT glass in cement mortar successfully prevented the leaching of lead. We conclude that it is feasible to utilize CRT glass in cement mortar production.

  16. Recycling of Rare Earth Elements

    Science.gov (United States)

    Lorenz, Tom; Bertau, Martin

    2017-01-01

    Any development of an effective process for rare earth (RE) recycling has become more and more challenging, especially in recent years. Since 2011, when commodity prices of REs had met their all-time maximum, prices have dropped rapidly by more than 90 %. An economic process able to offset these fluctuations has to take unconventional methods into account beside well-known strategies like acid/basic leaching or solvent extraction. The solid-state chlorination provides such an unconventional method for mobilizing RE elements from waste streams. Instead of hydrochloric acid this kind of chlorination decomposes NH4Cl thermally to release up to 400 °C hot HCl gas. After cooling the resulting solid metal chlorides may be easily dissolved in pH-adjusted water. Without producing strongly acidic wastes and with NH4Cl as cheap source for hydrogen chloride, solid-state chlorination provides various advantages in terms of costs and disposal. In the course of the SepSELSA project this method was examined, adjusted and optimized for RE recycling from fluorescent lamp scraps as well as Fe14Nd2B magnets. Thereby many surprising influences and trends required various analytic methods to examine the reasons and special mechanisms behind them.

  17. Recycling waste brick from construction and demolition of buildings as pozzolanic materials.

    Science.gov (United States)

    Lin, Kae-Long; Wu, Hsiu-Hsien; Shie, Je-Lueng; Hwang, Chao-Lung; An Cheng

    2010-07-01

    This investigation elucidates the pozzolic characteristics of pastes that contain waste brick from building construction and demolition wastes. The TCLP leaching concentrations of waste brick for the target cations or heavy metals were all lower than the current regulatory thresholds of the Taiwan EPA. Waste brick had a pozzolanic strength activity index of 107% after 28 days. It can be regarded as a strong pozzolanic material. The compressive strengths of waste brick blended cement (WBBC) that contain 10% waste brick increased from 71.2 MPa at 28 days to 75.1 MPa at 60 days, an increase of approximately 5% over that period. At 28 days, the pozzolanic reaction began, reducing the amount of Ca(OH)(2) and increasing the densification. The intensity of the peak at 3640 cm(- 1) associated with Ca(OH)(2) is approximately the same for ordinary Portland cement (OPC) pastes. The hydration products of all the samples yield characteristics peaks at 978 cm(-1) associated with C-S-H, and at ~3011 cm(-1) and 1640 cm(-1) associated with water. The samples yield peaks at 1112 cm(-1), revealing the formation of ettringite. In WBBC pastes, the ratio Q(2)/Q(1) increases with curing time. These results demonstrate that increasing the curing time increases the number of linear polysilicate anions in C-S-H. Experimental results reveal that waste brick has potential as a pozzolanic material in the partial replacement of cement.

  18. Plastics recycling: challenges and opportunities.

    Science.gov (United States)

    Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

    2009-07-27

    Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3-4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it

  19. Recycling power plant slag for use as aggregate in precast concrete components

    Directory of Open Access Journals (Sweden)

    Orna Carmona, M.

    2010-12-01

    Full Text Available The need to eliminate waste generates costs. When considering the preservation of the environment, the minimization of the consumption of natural resources and energy savings criteria, the need and advisability of studying the feasibility of waste re-use seems clear. However, waste re-use depends on whether they are economically competitive. Therefore, the aim of this study is to evaluate the possible use of slag from a steam power station as aggregate in the manufacture of concrete. This study included the determination of the physical, chemical and thermal properties of the material, comparing the results to those required by the Spanish structural concrete code (EHE in determining their acceptance or rejection as a concrete component. The ultimate aim of the research was to determine the highest slag content that could be added to concrete without modifying its strength or durability, with a view to obtaining savings in the manufacture of precast structures.

    La necesidad de eliminar residuos genera gastos. Considerando criterios de conservación ambiental, minimización del consumo de recursos naturales y ahorro de energía parece claro la necesidad y conveniencia de estudiar la viabilidad del uso de residuos. Sin embargo la utilización de residuos depende de que sean competitivos económicamente. Por tanto el propósito de esta investigación es evaluar el posible uso de las escorias de fondo de una central térmica como áridos para la fabricación de hormigón. En este estudio se incluye la determinación de características físicas, químicas y térmicas y se han comparado los resultados a los requeridos por la EHE para determinar su aceptación o rechazo como componente de un hormigón. El objetivo final de la investigación responde a la utilización de hormigón con el máximo contenido en escorias sin modificar las condiciones de resistencia y durabilidad, consiguiendo un ahorro económico en la fabricación de estructuras

  20. Mesoporous ZrO2 fibers with enhanced surface area and the application as recyclable absorbent

    Science.gov (United States)

    Yu, Zhichao; Liu, Benxue; Zhou, Haifeng; Feng, Cong; Wang, Xinqiang; Yuan, Kangkang; Gan, Xinzhu; Zhu, Luyi; Zhang, Guanghui; Xu, Dong

    2017-03-01

    Highly crystalline mesoporous zirconia fibers with high surface area have been prepared by the use of electrospinning combined with precursors method. The obtained precursor fibers were treated in water steam and directly in air at different temperature respectively. Compared with the direct calcination in air, the water steam cannot only promote the crystallization of ZrO2 but also effectively remove off the organics and prevent the pore structure collapse. Moreover, through adding hydrochloric acid to modify the solution pH value, the obtained t-ZrO2 fibers treated in water steam at 300 °C have high surface area and large pore volume of 232.70 m2 g-1 and 0.36 cm3 g-1. The formation mechanism of the mesostucture was studied and the schematic was represented. Compared with the previous reports of mesoporous ZrO2 fibers, the as-synthesized materials exhibited the high crystallinity, large surface area and the long-range order mesostructure.The adsorption of Congo red indicates that the samples have a high adsorption capacity of 103.46 mg g-1 and long-periodic repeated availability.

  1. 含再生材料的PC/PET无卤阻燃合金加工稳定性%Processing Stability of Recycled Materials PC/PET Alloy Containing Halogen-Free Flame Retardant

    Institute of Scientific and Technical Information of China (English)

    高磊; 李强; 李文强; 罗明华

    2016-01-01

    通过对再生聚对苯二甲酸乙二酯(PET–R)的多次挤出,研究了扩链对PET–R稳定性的影响。同时,也通过多次挤出和多次注塑的Regrind实验,研究了丙烯腈–苯乙烯塑料接枝甲基丙烯酸缩水甘油酯(AS-g-GMA)加入后再生聚碳酸酯(PC)/PET体系的相容性和稳定性,以及熔体流动速率和冲击强度的变化。通过11个月内的生产数据反映出,经过扩链和稳定化处理后的含再生材料的PC/PET无卤阻燃合金具有很好的加工稳定性。%The influence of chain extending on the stability of recycled polyethylene terephthalate (PET–R) was studied by multi-extrusion experiment. Meanwhile the changes of compatibility, stability, melt flow rate and impact strength of recycled polycarbonate (PC–R)/PET–R alloy after adding acrylonitrile-styrene grafted glycidyl methacrylate (AS-g-GMA) was discussed through multi-extrusion and multi-injection Regrind experiments. The production data of eleven months indicates that after the process of chain extending and stabilizing, the halogen-free flame retardant PC/PET alloy containing recycled materials has better stabilization.

  2. Recycling of agroindustrial solid wastes as additives in brick manufacturing for development of sustainable construction materials

    Directory of Open Access Journals (Sweden)

    Lisset Maritza Luna-Cañas

    2014-01-01

    Full Text Available La acumulación de residuos sólidos agroindustriales no administ rados especialmente en los países en vías de desarrollo ha dado lugar a una creciente preocupación ambiental. El reciclaje de tales res iduos como un material de construcción sostenible parece ser un a solución viable no sólo al problema de la contaminación, sino también un a opción económica para diseñar edificios verdes. El presente t rabajo estudia la aplicación de varios residuos agroindustriales en la fabricación de ladrillos, que incluyen cáscara de cacao, aserr ín, cáscara de arroz y caña de azúcar. En primer lugar, se determinó la compos ición mineralógica y química de los residuos y del suelo arcill oso. A continuación, los ladrillos se fabricaron con diferentes cantid ades de residuos (5%, 10% y 20%. El efecto de la adición de es tos residuos en el comportamiento tecnológico del ladrillo se evaluó mediant e ensayos de resistencia a la compresión, resistencia a la flex ión y durabilidad. Con base en los resultados obtenidos, las cantidad es óptimas de residuos agroindustriales para obtener ladrillos fueron mezclando 10% de cáscara de cacao y 90% de suelo arcilloso. Est os porcentajes producen ladrillos cuyas propiedades mecánicas e ran adecuadas para su uso como materias primas secundarias en la pr oducción de ladrillos.

  3. Incorporation of N-doped TiO2 nanorods in regenerated cellulose thin films fabricated from recycled newspaper as a green portable photocatalyst.

    Science.gov (United States)

    Mohamed, Mohamad Azuwa; Salleh, W N W; Jaafar, Juhana; Ismail, A F; Abd Mutalib, Muhazri; Jamil, Siti Munira

    2015-11-20

    In this work, an environmental friendly RC/N-TiO2 nanocomposite thin film was designed as a green portable photocatalyst by utilizing recycled newspaper as sustainable cellulose resource. Investigations on the influence of N-doped TiO2 nanorods incorporation on the structural and morphological properties of RC/N-TiO2 nanocomposite thin film are presented. The resulting nanocomposite thin film was characterized by FESEM, AFM, FTIR, UV-vis-NIR spectroscopy, and XPS analysis. The results suggested that there was a remarkable compatibility between cellulose and N-doped TiO2 nanorods anchored onto the surface of the RC/N-TiO2 nanocomposite thin film. Under UV and visible irradiation, the RC/N-TiO2 nanocomposite thin film showed remarkable photocatalytic activity for the degradation of methylene blue solution with degradation percentage of 96% and 78.8%, respectively. It is crucial to note that the resulting portable photocatalyst produced via an environmental and green technique in its fabrication process has good potential in the field of water and wastewater treatment application.

  4. Green Science: Revisiting Recycling

    Science.gov (United States)

    Palliser, Janna

    2011-01-01

    Recycling has been around for a long time--people have reused materials and refashioned them into needed items for thousands of years. More recently, war efforts encouraged conservation and reuse of materials, and in the 1970s recycling got its official start when recycling centers were created. Now, curbside recycling programs and recycling…

  5. Thermal response and recyclability of poly(stearylacrylate-co-ethylene glycol dimethacrylate) gel as a VOCs absorbent

    Science.gov (United States)

    The development of absorbent materials for volatile organic compounds (VOCs) is in demand for a variety of environmental applications including protective barriers for VOCs point sources. One of the challenges for the currently available VOCs absorbents is their recyclability. In this study, we syn...

  6. On-Farm Water Recycling as an Adaptation Strategy for Drained Agricultural Land in the Western Lake Erie Basin

    Science.gov (United States)

    On-farm water recycling is in agricultural landscapes today, and a few examples exist in the Great Lakes region. They have been implemented primarily where both irrigation is needed for high value crops and groundwater is inadequate to provide the rates needed. Crop yield benefits of irrigation fr...

  7. Hydroxyapatite supported caesium carbonate as a new recyclable solid base catalyst for the Knoevenagel condensation in water

    Directory of Open Access Journals (Sweden)

    Monika Gupta

    2009-11-01

    Full Text Available The Knoevenagel condensation between aromatic aldehydes and malononitrile, ethyl cyanoacetate or malonic acid with hydroxyapatite supported caesium carbonate in water is described. HAP–Cs2CO3 was found to be a highly active, stable and recyclable catalyst under the reaction conditions.

  8. Study of Recycled and Virgin Compounded Metal Injection Moulded Feedstock for Stainless Steel 630

    Science.gov (United States)

    Manonukul, Anchalee; Likityingwara, Warakij; Rungkiatnawin, Phataraporn; Muenya, Nattapol; Amoranan, Suttha; Kittinantapol, Witoo; Surapunt, Suphachai

    Fine rounded powders preferable for metal injection moulding (MIM) are expensive. This forces MIM makers to recycle green scraps, for example, the runner system and defected green parts. This is particularly necessary for injection moulded small parts where parts are only a small portion of the injection short size. There is very little published data, although recycling feedstock has been practise throughout the industry. This work aims at investigating the effects of recycled stainless steel 630 feedstock content on the density, mechanical properties, dimensional changes and microstructure. Five batches of compounded virgin and recycled feedstock were studies from 0% to 100% recycled feedstock with the increment of 25%. Homogenously compounded feedstock was injected using the same injection condition. Subsequently, green parts were debinded and sintered at 1325°C for 2 hours in argon atmosphere. The results suggest that the green density increases linearly with increasing percentage of recycled feedstock because the polymeric binder was broken down during previous process. However, the sintered density remains nominally constant. As a result, the mechanical properties and microstructure of sintered parts are independent of recycled feedstock content. However, the volumetric and linear shrinkage decreases linearly with the increase in percentage of recycled feedstock. The difference in shrinkage is vital to dimensional control during commercial production. For example, only 4.5% of recycled feedstock can be added to virgin feedstock if a tolerance of ±0.3 mm is required for a 25 mm MIM part.

  9. Prussian blue analogue derived magnetic carbon/cobalt/iron nanocomposite as an efficient and recyclable catalyst for activation of peroxymonosulfate.

    Science.gov (United States)

    Lin, Kun-Yi Andrew; Chen, Bo-Jau

    2017-01-01

    A Prussian blue analogue, cobalt hexacyanoferrate Co3[Fe(CN)6]2, was used for the first time to prepare a magnetic carbon/cobalt/iron (MCCI) nanocomposite via one-step carbonization of Co3[Fe(CN)6]2. The resulting MCCI consisted of evenly-distributed cobalt and cobalt ferrite in a porous carbonaceous matrix, making it an attractive magnetic heterogeneous catalyst for activating peroxymonosulfate (PMS). As Rhodamine B (RhB) degradation was adopted as a model test for evaluating activation capability of MCCI, factors influencing RhB degradation were thoroughly examined, including MCCI and PMS dosages, temperature, pH, salt and radical scavengers. A higher MCCI dosage noticeably facilitated the degradation kinetics, whereas insufficient PMS dosage led to ineffective degradation. RhB degradation by MCCI-activated PMS was much more favorable at high temperatures and under neutral conditions. The presence of high concentration of salt slightly interfered with RhB degradation by MCCI-activated PMS. Through examining effects of radical scavengers, RhB degradation by MCCI-activated PMS can be primarily attributed to sulfate radicals instead of a combination of sulfate and hydroxyl radicals. Compared to Co3O4, a typical catalyst for PMS activation, MCCI also exhibited a higher catalytic activity for activating PMS. In addition, MCCI was proven as a durable and recyclable catalyst for activating PMS over multiple cycles without efficiency loss and significant changes of chemical characteristics. These features demonstrate that MCCI, simply prepared from a one-step carbonization of Co3[Fe(CN)6]2 is a promising heterogeneous catalyst for activating PMS to degrade organic pollutants.

  10. Recycling of merchant ships

    Directory of Open Access Journals (Sweden)

    Magdalena Klopott

    2013-12-01

    Full Text Available The article briefly outlines the issues concerning ship recycling. It highlights ships' high value as sources of steel scrap and non-ferrous metals, without omitting the fact that they also contain a range of hazardous substances. Moreover, the article also focuses on basic ship demolition methods and their environmental impact, as well as emphasizes the importance of “design for ship recycling” philosophy.

  11. Possibilities for recycling cellulases after use in cotton processing: part I: Effects of end-product inhibition, thermal and mechanical deactivation, and cellulase depletion by adsorption.

    Science.gov (United States)

    Azevedo, Helena; Bishop, David; Cavaco-Paul, Artur

    2002-04-01

    Preliminary recycling experiments with cellulase enzymes after cotton treatments at 50 degrees C showed that activity remaining in the treatment liquors was reduced by about 80% after five recycling steps. The potential problems of end-product inhibition, thermal and mechanical deactivation, and the loss of some components of the cellulase complex by preferential and or irreversible adsorption to cotton substrates were studied. End-product inhibition studies showed that the build-up of cellobiose and glucose would be expected to cause no more than 40% activity loss after five textile treatment cycles. Thermal and mechanical treatments of cellulases suggested that the enzymes start to be deactivated at 60 degrees C and agitation levels similar to those used in textile processing did not cause significant enzyme deactivation. Analysis of cellulase solutions, by fast protein liquid chromatography, before and after adsorption on cotton fabrics, suggested that the cellobiohydrolase II (Cel6A) content of the cellulase complex was reduced, relative to the other components, by preferential adsorption. This would lead to a marked reduction in activity after several treatment cycles and top-up with pure cellobiohydrolase II would be necessary unless this component is easily recoverable from the treated fabric.

  12. Development of Agricultural Recycle Economy in Arid Areas of Hexi Corridor——A Case Study of Zhangye City, China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Taking Zhangye City as an example, the thesis analyzes the restricted factors of resources and environment confronted by the agriculture in arid area of Hexi Corridor: the first is the agricultural natural resources. The area of cultivated land decreases year by year, and there are sharp decrease of biological diversity as well as the shortage and waste of water resources; the second is the ecological environment. There are critical soil erosion, frequent natural disaster and outstanding agricultural area source pollution; the third is the rural economy. The agricultural structure still can not meet the need of agricultural development in recent years, and the proportion of agricultural product processing is low. It points out that implementation of agricultural recycle economy is the necessary choice of the agricultural development in Zhangye City. Developing recycle economy is conducive to improving ecological environment and realizing agricultural sustainable development; developing recycle economy can solve the agricultural area source pollution to much extent and protect rural environment; developing recycle economy is conducive to adjusting rural industrial structure, increasing job opportunities and increasing farmers’ income; developing recycle economy is conducive to elevating the international competitiveness of agricultural products. The thesis also has put forward the countermeasures of developing agricultural recycle economy in Zhangye City as follows: firstly, fostering the ambience of the development of agricultural recycle economy; secondly, forming the incentive mechanism of development of agricultural recycle economy; thirdly, broadening the investment channel of development of agricultural recycle economy; fourthly, perfecting socialized service system of agricultural recycle economy.

  13. Evaluating the progress of the UK's Material Recycling Facilities: a mini review.

    Science.gov (United States)

    Ali, Muhammad; Courtenay, Peter

    2014-12-01

    Over the last 15 years, the UK has made great strides in reducing the amount of waste being sent to landfill while also increasing the amount of waste being recycled. The key drivers for this change are the European Union Landfill Directive (1999/31/EC) and the UK Landfill Tax. However, also playing their part are the growing numbers of Material Recycling Facilities (MRFs), which process recyclables. This mini review evaluates the current state of MRFs in the UK, through extensive secondary research, and detailed primary data analysis focussing on MRFs located in South-East England, UK. This study also explores technologies that aim to generate energy from waste, including Waste-to-Energy (WtE) and Refuse-derived Fuel (RDF) facilities. These facilities can have a huge appetite for waste, which can be detrimental to recycling efforts as some of the waste being sent there should be recycled. It was found that the waste sent to a typical UK MRF would recycle around 92% of materials while 6% was sent to energy recovery and the remaining 2% ended up in landfill. Therefore, the total estimated rejected or non-compliance materials from MRFs are around 8%. A key recommendation from this study is to adopt a strategy to combine MRFs with a form of energy generation, such as WtE or RDF. This integrated approach would ensure any residual waste arising from the recycling process can be used as a sustainable fuel, while also increasing the recycling rates.

  14. Length sensing and control of a Michelson interferometer with Power Recycling and Twin Signal Recycling cavities

    CERN Document Server

    Gräf, Christian; Vahlbruch, Henning; Danzmann, Karsten; Schnabel, Roman

    2012-01-01

    The techniques of power recycling and signal recycling have proven as key concepts to increase the sensitivity of large-scale gravitational wave detectors by independent resonant enhancement of light power and signal sidebands within the interferometer. Developing the latter concept further, twin signal recycling was proposed as an alternative to conventional detuned signal recycling. Twin signal recycling features the narrow-band sensitivity gain of conventional detuned signal recycling but furthermore facilitates the injection of squeezed states of light, increases the detector sensitivity over a wide frequency band and requires a less complex detection scheme for optimal signal readout. These benefits come at the expense of an additional recycling mirror, thus increasing the number of degrees of freedom in the interferometer which need to be controlled. In this article we describe the development of a length sensing and control scheme and its successful application to a tabletop-scale power recycled Michel...

  15. Ascorbate recycling in human neutrophils: Induction by bacteria

    OpenAIRE

    Wang, Yaohui; Russo, Thomas A.; Kwon, Oran; Chanock, Stephen; Rumsey, Steven C.; Levine, Mark

    1997-01-01

    Ascorbate (vitamin C) recycling occurs when extracellular ascorbate is oxidized, transported as dehydroascorbic acid, and reduced intracellularly to ascorbate. We investigated microorganism induction of ascorbate recycling in human neutrophils and in microorganisms themselves. Ascorbate recycling was determined by measuring intracellular ascorbate accumulation. Ascorbate recycling in neutrophils was induced by both Gram-positive and Gram-negative pathogenic bacteria, and the fungal pathogen C...

  16. Recycling dodecylamine intercalated vanadate nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Odair P., E-mail: odair@iqm.unicamp.br; Souza Filho, Antonio G., E-mail: agsf@fisica.ufc.br; Alves, Oswaldo L., E-mail: oalves@iqm.unicamp.b [Universidade Estadual de Campinas-UNICAMP, LQES - Laboratorio de Quimica do Estado Solido, Instituto de Quimica (Brazil)

    2010-01-15

    In this article, we report the thermal decomposition processes of dodecylamine intercalated vanadate nanotubes and their recycling process. Structural, vibrational, and morphological properties of the annealed samples were investigated by X-ray diffraction, infrared spectroscopy, and scanning electron microscopy, respectively. The data analysis unveiled that vanadate nanotubes (VONTs) decompose into nanoplates which is isostructural to xerogel, and finally to nanoparticle aggregates whose composition is a single V{sub 2}O{sub 5} bulk phase. These aggregates can be successfully recycled for converting the residues of decomposition process into vanadate nanotubes again.

  17. Polymer recycling: potential application of radiation technology

    Energy Technology Data Exchange (ETDEWEB)

    Burillo, Guillermina; Clough, Roger L. E-mail: rlcloug@sandia.gov; Czvikovszky, Tibor; Guven, Olgun; Le Moel, Alain; Liu Weiwei; Singh, Ajit; Yang Jingtian; Zaharescu, Traian

    2002-04-01

    Management of solid waste is an important problem, which is becoming progressively worse as a byproduct of continuing economic growth and development. Polymeric materials (plastics and rubbers) comprise a steadily increasing proportion of the municipal and industrial waste going into landfill. Development of technologies for reducing polymeric waste, which are acceptable from the environmental standpoint, and which are cost-effective, has proven to be a difficult challenge due to complexities inherent in the reuse of polymers. Establishing optimal processes for the reuse/recycling of polymeric materials thus remains a worldwide challenge as we enter the new century. Due to the ability of ionizing radiation to alter the structure and properties of bulk polymeric materials, and the fact that it is applicable to essentially all polymer types, irradiation holds promise for impacting the polymer waste problem. The three main possibilities for use of radiation in this application are: (1) enhancing the mechanical properties and performance of recovered materials or material blends, principally through crosslinking, or through surface modification of different phases being combined; (2) treatment causing or enhancing the decomposition of polymers, particularly through chain scission, leading to recovery of either low molecular weight mixtures, or powders, for use as chemical feedstocks or additives; (3) production of advanced polymeric materials designed for environmental compatibility. This paper provides an overview of the polymer recycling problem, describes the major technological obstacles to the implementation of recycling technologies, and outlines some of the approaches being taken. A review of radiation-based recycling research is then provided, followed by a discussion of future directions where irradiation may be relevant to the problems currently inhibiting the widespread recycling of polymeric materials.

  18. Recycling of Advanced Batteries for Electric Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    JUNGST,RUDOLPH G.

    1999-10-06

    The pace of development and fielding of electric vehicles is briefly described and the principal advanced battery chemistries expected to be used in the EV application are identified as Ni/MH in the near term and Li-ion/Li-polymer in the intermediate to long term. The status of recycling process development is reviewed for each of the two chemistries and future research needs are discussed.

  19. Science as a market process

    CERN Multimedia

    Walstead, A

    2002-01-01

    "This article is intended as a manifesto for an economic theory of scientific inquiry. My focus is not on traditional economic concerns about how societal resources are allocated to the funding of science and how scientific research contributes to technological advances and economic growth. Rather, my attention centers on using economic concepts to illuminate the conduct of scientific inquiry itself" (5 pages).

  20. Sulfuric Acid ([3-(3-Silicapropyl)sulfanyl]propyl)ester as a Recyclable Catalyst for the Synthesis of 4,4'-(Arylmethylene)bis(1H-pyrazol-5-ols)%Sulfuric Acid ([3-(3-Silicapropyl)sulfanyl]propyl)ester as a Recyclable Catalyst for the Synthesis of4,4'-(Arylmethylene)bis(1H-pyrazol-5-ols)

    Institute of Scientific and Technical Information of China (English)

    Shekoofeh TAYEBI; Mojtaba BAGHERNEJAD; Dariush SABERI; Khodabakhsh NI KNAM

    2011-01-01

    Sulfuric acid ([3-(3-silicapropyl)sulfanyl]propyl)ester is employed as a recyclable catalyst for the condensation reaction between aromatic aldehydes and 3-methyl-l-phenyl-5-pyrazolone.This condensation reaction was performed in ethanol under refluxing conditions giving 4,4-alkylmethylene-bis(3-methyl-5-pyrazolones) in 74-90% yields.The heterogeneous catalyst was recycled and used in eleven runs for the reaction between benzaldehyde and 3-methyl-l-phenyl-5-pyrazolone without losing catalytic activity.

  1. Study on Concrete Containing Recycled Aggregates Immersed in Epoxy Resin

    Directory of Open Access Journals (Sweden)

    Adnan Suraya Hani

    2017-01-01

    Full Text Available In recent decades, engineers have sought a more sustainable method to dispose of concrete construction and demolition waste. One solution is to crush this waste concrete into a usable gradation for new concrete mixes. This not only reduces the amount of waste entering landfills but also alleviates the burden on existing sources of quality natural concrete aggregates. There are too many kinds of waste but here constructions waste will be the priority target that should be solved. It could be managed by several ways such as recycling and reusing the concrete components, and the best choice of these components is the aggregate, because of the ease process of recycle it. In addition, recycled aggregates and normal aggregates were immersed in epoxy resin and put in concrete mixtures with 0%, 5%, 10% and 20% which affected the concrete mixtures properties. The strength of the concrete for both normal and recycled aggregates has increased after immersed the aggregates in epoxy resin. The percentage of water absorption and the coefficient of water permeability decreased with the increasing of the normal and the recycled aggregates immersed in epoxy resin. Generally the tests which have been conducted to the concrete mixtures have a significant results after using the epoxy resin with both normal and recycled aggregates.

  2. Green and efficient synthesis of novel bispyrazoles through a tandem Knoevenagel and Michael type reaction using nanowire zinc oxide as a powerful and recyclable catalyst

    OpenAIRE

    ESKANDARI, Khalil; KARAMI, Bahador; Khodabakhshi, Saeed; HOSEINI, SEYYED JAFAR

    2015-01-01

    Zinc oxide nanowires (ZnO NWs) were prepared and characterized by scanning electron microscopy, powder X-ray diffraction, and transmission electron microscopy analyses. ZnO NWs were then employed as heterogeneous and recyclable catalyst for green synthesis of some new and known bispyrazole derivatives through a tandem Knoevenagel and Michael type addition reaction of aromatic aldehyde and pyrazolone. The synthetic method is operationally simple and affords product with high yields in short re...

  3. The use of anhydrous CeCl{sub 3} as a recyclable and selective catalyst for the acetalization of aldehydes and ketones

    Energy Technology Data Exchange (ETDEWEB)

    Silveira, Claudio C.; Mendes, Samuel R.; Ziembowicz, Francieli I. [Universidade Federal de Santa Maria (UFSM), RS (Brazil). Dept. de Quimica; Lenardao, Eder J.; Perin, Gelson [Universidade Federal de Pelotas (UFPel), RS (Brazil). Inst. de Quimica e Geociencias

    2010-07-01

    An efficient, clean, chemoselective and solvent-free method for the synthesis of ketone and aldehyde dimethyl acetals was developed using trimethyl orthoformate and commercially available anhydrous CeCl{sub 3} as a recyclable catalyst. The method is general and affords the protected carbonyl compounds in good yields and under mild conditions, including aryl and alkyl ketones and activated aldehydes. The catalyst could be utilised directly for 3 cycles, without significant loss of activity. (author)

  4. An improved procedure for synthesis of some new 1,3-diaryl-2-propen-1-ones using PEG-400 as a recyclable solvent and their antimicrobial evaluation.

    Science.gov (United States)

    Dawane, Bhaskar S; Konda, Shankaraiah G; Shaikh, Baseer M; Bhosale, Raghunath B

    2009-12-01

    A simple and convenient route is described for the synthesis of novel hetero 1,3-diaryl-2-propen-1-ones (chalcones) by using recyclable PEG-400 as an alternative reaction solvent. The reaction is clean with excellent yield, shorter reaction time and reduces the use of volatile organic compounds (VOCs). All the synthesized compounds were evaluated for their antimicrobial activities against several pathogenic representatives.

  5. Reciclar e colar: os papéis do compositor e do intérprete na criação colaborativa Recycling and collaging: the roles of composer and performer inside a collaborative creation process

    Directory of Open Access Journals (Sweden)

    Daniel Serale

    2012-06-01

    Full Text Available Este artigo analisa a interconexão entre compositor e intérprete no processo de criação colaborativa. Neste processo, exemplificado através da obra Recycling Collaging Sampling de Edson Zampronha, a interação de ambos papeis resulta em um trabalho cuja pertencência e autoria são igualmente compartilhados.This article analyzes the interconnection between composer and performer inside a collaborative creation process. In this process, exemplified through the Edson Zampronha's work Recycling Collaging Sampling, the interaction between both roles results in a work which sense of belonging and authorship are equally shared.

  6. Environmental risk assessment of CRT and PCB workshops in a mobile e-waste recycling plant.

    Science.gov (United States)

    Song, Qingbin; Zeng, Xianlai; Li, Jinhui; Duan, Huabo; Yuan, Wenyi

    2015-08-01

    The mobile e-waste recycling equipment was chosen as the object of this study, including manual dismantling, mechanical separation of cathode ray tubes (CRTs), and printed circuit boards (PCBs) in the two independent workshops. To determine the potential environmental contamination, the noise, the heavy metals (Cu, Cd, Pb), and the environmental impacts of the e-waste recycling processes in the two workshops of the mobile plant have been evaluated in this paper. This study determined that when control measures are employed, the noise within the two workshops (e-waste recycling process as a whole.

  7. Modelling Recycling Targets

    DEFF Research Database (Denmark)

    hill, amanda; Leinikka Dall, Ole; Andersen, Frits Møller

    2014-01-01

    Within the European Union (EU) a paradigm shift is currently occurring in the waste sector, where EU waste directives and national waste strategies are placing emphasis on resource efficiency and recycling targets. The most recent Danish resource strategy calculates a national recycling rate of 22......% for household waste, and sets an ambitious goal of a 50% recycling rate by 2020. This study integrates the recycling target into the FRIDA model to project how much waste and from which streams should be diverted from incineration to recycling in order to achieve the target. Furthermore, it discusses how...... the existing technological, organizational and legislative frameworks may affect recycling activities. The results of the analysis show that with current best practice recycling rates, the 50% recycling rate cannot be reached without recycling of household biowaste. It also shows that all Danish municipalities...

  8. Recycling of typical supercapacitor materials.

    Science.gov (United States)

    Vermisoglou, Eleni C; Giannouri, Maria; Todorova, Nadia; Giannakopoulou, Tatiana; Lekakou, Constantina; Trapalis, Christos

    2016-04-01

    A simple, facile and low-cost method for recycling of supercapacitor materials is proposed. This process aims to recover some fundamental components of a used supercapacitor, namely the electrolyte salt tetraethyl ammonium tetrafluoroborate (TEABF4) dissolved in an aprotic organic solvent such as acetonitrile (ACN), the carbonaceous material (activated charcoal, carbon nanotubes) purified, the current collector (aluminium foil) and the separator (paper) for further utilization. The method includes mechanical shredding of the supercapacitor in order to reduce its size, and separation of aluminium foil and paper from the carbonaceous resources containing TEABF4 by sieving. The extraction of TEABF4 from the carbonaceous material was based on its solubility in water and subsequent separation through filtering and distillation. A cyclic voltammetry curve of the recycled carbonaceous material revealed supercapacitor behaviour allowing a potential reutilization. Furthermore, as BF4(-) stemming from TEABF4 can be slowly hydrolysed in an aqueous environment, thus releasing F(-) anions, which are hazardous, we went on to their gradual trapping with calcium acetate and conversion to non-hazardous CaF2.

  9. The Pd(0) nanoparticles stabilized by collagen fibres as a recyclable heterogeneous catalyst for the Stille reaction under aerobic condition

    Indian Academy of Sciences (India)

    Babak Mohammadi-Aghdam; Siavash Bahari; Rahim Molaei

    2013-07-01

    The stabilized palladium(0) nanoparticles by collagen fibres was a highly active, air-stable and recyclable heterogeneous catalyst that could be used for the Stille coupling reactions between aryl iodides and organostannanes under aerobic conditions. This method offered the several advantages: high yield under facile reaction condition and easy work-up procedure. The catalyst was easily recovered from the reaction mixture by filtration and reused multiple times without significant reduction or decrease in the activity.

  10. Pollution characteristics and health risk assessment of volatile organic compounds emitted from different plastic solid waste recycling workshops.

    Science.gov (United States)

    He, Zhigui; Li, Guiying; Chen, Jiangyao; Huang, Yong; An, Taicheng; Zhang, Chaosheng

    2015-04-01

    The pollution profiles of volatile organic compounds (VOCs) emitted from different recycling workshops processing different types of plastic solid waste (PSW) and their health risks were investigated. A total of 64 VOCs including alkanes, alkenes, monoaromatics, oxygenated VOCs (OVOCs), chlorinated VOCs (ClVOCs) and acrylonitrile during the melting extrusion procedure were identified and quantified. The highest concentration of total VOCs (TVOC) occurred in the poly(acrylonitrile-butadiene styrene) (ABS) recycling workshop, followed by the polystyrene (PS), polypropylene (PP), polyamide (PA), polyvinyl chloride (PVC), polyethylene (PE) and polycarbonate (PC) workshops. Monoaromatics were found as the major component emitted from the ABS and PS recycling workshops, while alkanes were mainly emitted from the PE and PP recycling processes, and OVOCs from the PVC and PA recycling workshops. According to the occupational exposure limits' (OEL) assessment, the workers suffered acute and chronic health risks in the ABS and PS recycling workshops. Meanwhile, it was found that most VOCs in the indoor microenvironments were originated from the melting extrusion process, while the highest TVOC concentration was observed in the PS rather than in the ABS recycling workshop. Non-cancer hazard indices (HIs) of all individual VOCs were <1.0, whereas the total HI in the PS recycling workshop was 1.9, posing an adverse chronic health threat. Lifetime cancer risk assessment suggested that the residents also suffered from definite cancer risk in the PS, PA, ABS and PVC recycling workshops.

  11. Process analysis of effluent hydrocarbon recycling for coal pyrolysis to acetylene in thermal plasma%热等离子体煤制乙炔裂解气烃类循环过程分析

    Institute of Scientific and Technical Information of China (English)

    程炎; 颜彬航; 李天阳; 程易

    2015-01-01

    针对等离子体煤裂解制乙炔过程,提出了将过程裂解气中副产的烃类分离,循环输入等离子体反应器的新型工艺流程。基于新疆天业2 MW示范平台装置的典型运行参数,采用热力学分析手段,理论上分析了该工艺流程对于体系乙炔产量、单位质量乙炔煤耗和裂解电耗等的影响。结果表明,裂解气烃类循环可以有效提高裂解气中乙炔浓度和产率,同时减少煤粉输送气等流程气体的使用。典型操作条件下,采用裂解气烃类循环工艺可以增加35.6%的乙炔收率和13.4%的氢气收率,降低30%的单位乙炔煤耗和裂解电耗,是高效可行的优化方案。%Coal pyrolysis via thermal plasma provides an alternative path to realize the effective conversion from coal to acetylene. Recycling the hydrocarbons in the effluent gas to the plasma pyrolysis process is proposed in this work to improve the reactor performance. Thermodynamic analysis is made as the reference on the basis of the pilot-plant results of Xinjiang Tianye 2 MW plasma pyrolysis device. The comparison results show that the recycling of effluent hydrocarbons (except acetylene) can raise the volume fraction and mass flow rate of acetylene in the product gas. The hydrocarbons in cracked gas is ample to be used as the conveying and accelerating gas for coal and the protecting gas for plasma torch, which can reduce the input amount of working gas and optimize the whole gas flow of the process. Different optimization cases are discussed to compare the products (i.e., acetylene and hydrogen) output and the gas input of the thermal plasma pyrolysis system. The optimized results show that the recycling process is feasible and effective, with reduced coal consumption (30%) and pyrolysis energy consumption (30%) as well as increased acetylene yield (35.6%).

  12. Recyclability assessment of nano-reinforced plastic packaging

    Energy Technology Data Exchange (ETDEWEB)

    Sánchez, C., E-mail: csanchez@itene.com [Sustainability Divison, Packaging, Transport and Logistics Research Institute, Albert Einstein 1, 46980 Paterna, Valencia (Spain); Hortal, M., E-mail: mhortal@itene.com [Sustainability Divison, Packaging, Transport and Logistics Research Institute, Albert Einstein 1, 46980 Paterna, Valencia (Spain); Aliaga, C., E-mail: caliaga@itene.com [Sustainability Divison, Packaging, Transport and Logistics Research Institute, Albert Einstein 1, 46980 Paterna, Valencia (Spain); Devis, A., E-mail: adevis@itene.com [Sustainability Divison, Packaging, Transport and Logistics Research Institute, Albert Einstein 1, 46980 Paterna, Valencia (Spain); Cloquell-Ballester, V.A., E-mail: cloquell@dpi.upv.es [Dpto. Proyectos de Ingeniería, Universitat Politècnica de València, Camino de Vera, 46022 Valencia (Spain)

    2014-12-15

    Highlights: • The study compares the recyclability of polymers with and without nanoparticles. • Visual appearance, material quality and mechanical properties are evaluated. • Minor variations in mechanical properties in R-PE and R-PP with nanoparticles. • Slight degradation of R-PET which affect mechanical properties. • Colour deviations in recycled PE, PP and PET in ranges higher that 0.3 units. - Abstract: Packaging is expected to become the leading application for nano-composites by 2020 due to the great advantages on mechanical and active properties achieved with these substances. As novel materials, and although there are some current applications in the market, there is still unknown areas under development. One key issue to be addressed is to know more about the implications of the nano-composite packaging materials once they become waste. The present study evaluates the extrusion process of four nanomaterials (Layered silicate modified nanoclay (Nanoclay1), Calcium Carbonate (CaCO{sub 3}), Silver (Ag) and Zinc Oxide (ZnO) as part of different virgin polymer matrices of polyethylene (PE), Polypropylene (PP) and Polyethyleneterephtalate (PET). Thus, the following film plastic materials: (PE–Nanoclay1, PE–CaCO{sub 3}, PP–Ag, PET–ZnO, PET–Ag, PET–Nanoclay1) have been processed considering different recycling scenarios. Results on recyclability show that for PE and PP, in general terms and except for some minor variations in yellowness index, tensile modulus, tensile strength and tear strength (PE with Nanoclay1, PP with Ag), the introduction of nanomaterial in the recycling streams for plastic films does not affect the final recycled plastic material in terms of mechanical properties and material quality compared to conventional recycled plastic. Regarding PET, results show that the increasing addition of nanomaterial into the recycled PET matrix (especially PET–Ag) could influence important properties of the recycled material, due to a

  13. On the importance of cascading moisture recycling in South America

    NARCIS (Netherlands)

    Zemp, D.C.; Schleussner, C.F.; Barbosa, H.M.J.; Van der Ent, R.J.; Donges, J.F.; Heinke, J.; Sampaio, G.; Rammig, A.

    2014-01-01

    Continental moisture recycling is a crucial process of the South American climate system. In particular, evapotranspiration from the Amazon basin contributes substantially to precipitation regionally as well as over other remote regions such as the La Plata basin. Here we present an in-depth analysi

  14. The Development of Recycling Agent for Asphalt Pavement

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A type of recycling agent was developed and its use for modifying used asphalt is described.The results show that the viscosity and three main properties of the aged asphalt were remarkably improved.With 5%-7% content of recycling agent, the main properties of recycled asphalt comported with China GB asphalt standard AH-70 and the recycled asphalt concrete could be used as high-grade highway.Furthermore,the recycling mechanism of the aged asphalt is discussed.

  15. Life Cycle Assessment of Internal Recycling Options of Steel Slag in Chinese Iron and Steel Industry%Life Cycle Assessment of Internal Recycling Options of Steel Slag in Chinese Iron and Steel Industry

    Institute of Scientific and Technical Information of China (English)

    CHEN Bo; YANG Jian-xin; OUYANG Zhi-yun

    2011-01-01

    The internal recycling process of BOF slag which is one of the huge solid wastes from iron and steel indus try was emphasized. Based on the four scenarios of different internal recycling strategies for BOF slag, life cycle assessment (LCA) as a valuable t

  16. Flame retardant emission from e-waste recycling operation in northern Vietnam: environmental occurrence of emerging organophosphorus esters used as alternatives for PBDEs.

    Science.gov (United States)

    Matsukami, Hidenori; Tue, Nguyen Minh; Suzuki, Go; Someya, Masayuki; Tuyen, Le Huu; Viet, Pham Hung; Takahashi, Shin; Tanabe, Shinsuke; Takigami, Hidetaka

    2015-05-01

    Three oligomeric organophosphorus flame retardants (o-PFRs), eight monomeric PFRs (m-PFRs), tetrabromobisphenol A (TBBPA), and polybrominated diphenyl ethers (PBDEs) were identified and quantified in surface soils and river sediments around the e-waste recycling area in Bui Dau, northern Vietnam. Around the e-waste recycling workshops, 1,3-phenylene bis(diphenyl phosphate) (PBDPP), bisphenol A bis(diphenyl phosphate) (BPA-BDPP), triphenyl phosphate (TPHP), TBBPA, and PBDEs were dominant among the investigated flame retardants (FRs). The respective concentrations of PBDPP, BPA-BDPP, TPHP, TBBPA and the total PBDEs were 6.6-14000 ng/g-dry, e-waste, tris(methylphenyl) phosphate (TMPP), (2-ethylhexyl)diphenyl phosphate (EHDPP), TPHP, and the total PBDEs were abundantly with respective concentrations of e-waste have been determined to be important factors contributing to the emissions of FRs. The environmental occurrence of emerging FRs, especially o-PFRs, indicates that the alternation of FRs addition in electronic products is shifting in response to domestic and international regulations of PBDEs. The emissions of alternatives from open storage and burning of e-waste might become greater than those of PBDEs in the following years. The presence and environmental effects of alternatives should be regarded as a risk factor along with e-waste recycling.

  17. 离子膜蒸发工序蒸汽冷凝水回收再利用%Recycling and Reusing of Steam Condensate in the Ionic Membrane Evaporation Process

    Institute of Scientific and Technical Information of China (English)

    张守特; 赵军军; 刘立勤

    2014-01-01

    A great deal of condensate will be produced during the process of alkali consolidation. The liquid is mainly used as make-up water for cooling tower and as cooling water for pump. Because of the high temperature,before its recycling and reusing,the condensate needs to be cooled,which causes a waste of heat. This paper introduced ref-ormation measures of recycling and reusing of alkali-containing condensate in the ionic membrane evaporation system and proposed a solution of condensate separation based on different temperatures to deliver higher temperature liquid to the salt dissolving process. This will not only make full use of surplus heat,but only save a great many of process water.%烧碱浓缩的过程中会产生大量的冷凝水,主要作为凉水塔的补充水和机泵冷却水。由于冷凝水温度较高,其回收再利用前需要进行冷却,造成热量的浪费。介绍了离子膜蒸发系统含碱冷凝水循环再利用的改造措施,提出将不同温度的冷凝水分开,将温度高的部分送至化盐工序,不仅能将热量充分利用起来,还可以节约大量生产用水。

  18. Transverse Instabilities in the Fermilab Recycler

    Energy Technology Data Exchange (ETDEWEB)

    Prost, L.R.; Burov, A.; Shemyakin, A.; Bhat, C.M.; Crisp, J.; Eddy, N.; /Fermilab

    2011-07-01

    Transverse instabilities of the antiproton beam have been observed in the Recycler ring soon after its commissioning. After installation of transverse dampers, the threshold for the instability limit increased significantly but the instability is still found to limit the brightness of the antiprotons extracted from the Recycler for Tevatron shots. In this paper, we describe observations of the instabilities during the extraction process as well as during dedicated studies. The measured instability threshold phase density agrees with the prediction of the rigid beam model within a factor of 2. Also, we conclude that the instability threshold can be significantly lowered for a bunch contained in a narrow and shallow potential well due to effective exclusion of the longitudinal tails from Landau damping.

  19. Preconceptual Design Description for Caustic Recycle Facility

    Energy Technology Data Exchange (ETDEWEB)

    Sevigny, Gary J.; Poloski, Adam P.; Fountain, Matthew S.; Kurath, Dean E.

    2008-04-12

    The U.S. Department of Energy plans to vitrify both high-level and low-activity waste at the Hanford Site in southeastern Washington State. One aspect of the planning includes a need for a caustic recycle process to separate sodium hydroxide for recycle. Sodium is already a major limitation to the waste-oxide loading in the low-activity waste glass to be vitrified at the Waste Treatment Plant, and additional sodium hydroxide will be added to remove aluminum and to control precipitation in the process equipment. Aluminum is being removed from the high level sludge to reduce the number of high level waste canisters produced. A sodium recycle process would reduce the volume of low-activity waste glass produced and minimize the need to purchase new sodium hydroxide, so there is a renewed interest in investigating sodium recycle. This document describes an electrochemical facility for recycling sodium for the WTP.

  20. COMPOSITES FROM RECYCLED WOOD AND PLASTICS

    Science.gov (United States)

    The ultimate goal of this research was to develop technology to convert recycled wood fiber and plastics into durable products that are recyclable and otherwise environmentally friendly. Two processing technologies were used to prepare wood-plastic composites: air-laying and melt...

  1. Phosphate recycling in the phosphorus industry

    NARCIS (Netherlands)

    Schipper, W.J.; Klapwijk, A.; Potjer, A.; Rulkens, W.H.; Temmink, B.G.; Kiestra, F.D.G.; Lijmbach, A.C.M.

    2001-01-01

    The feasibility of phosphate recycling in the white phosphorus production process is discussed. Several types of materials may be recycled, provided they are dry inorganic materials, low in iron, copper and zinc. Sewage sludge ash may be used if no iron is used for phosphate precipitation in the tre

  2. Recycling of irradiated high-density polyethylene

    Science.gov (United States)

    Navratil, J.; Manas, M.; Mizera, A.; Bednarik, M.; Stanek, M.; Danek, M.

    2015-01-01

    Radiation crosslinking of high-density polyethylene (HDPE) is a well-recognized modification of improving basic material characteristics. This research paper deals with the utilization of electron beam irradiated HDPE (HDPEx) after the end of its lifetime. Powder of recycled HDPEx (irradiation dose 165 kGy) was used as a filler into powder of virgin low-density polyethylene (LDPE) in concentrations ranging from 10% to 60%. The effect of the filler on processability and mechanical behavior of the resulting mixtures was investigated. The results indicate that the processability, as well as mechanical behavior, highly depends on the amount of the filler. Melt flow index dropped from 13.7 to 0.8 g/10 min comparing the lowest and the highest concentration; however, the higher shear rate the lower difference between each concentration. Toughness and hardness, on the other hand, grew with increasing addition of the recycled HDPEx. Elastic modulus increased from 254 to 450 MPa and material hardness increased from 53 to 59 ShD. These results indicate resolving the problem of further recycling of irradiated polymer materials while taking advantage of the improved mechanical properties.

  3. Comparison of actinides and fission products recycling scheme with the normal plutonium recycling scheme in fast reactors

    Directory of Open Access Journals (Sweden)

    Salahuddin Asif

    2013-01-01

    Full Text Available Multiple recycling of actinides and non-volatile fission products in fast reactors through the dry re-fabrication/reprocessing atomics international reduction oxidation process has been studied as a possible way to reduce the long-term potential hazard of nuclear waste compared to that resulting from reprocessing in a wet PUREX process. Calculations have been made to compare the actinides and fission products recycling scheme with the normal plutonium recycling scheme in a fast reactor. For this purpose, the Karlsruhe version of isotope generation and depletion code, KORIGEN, has been modified accordingly. An entirely novel fission product yields library for fast reactors has been created which has replaced the old KORIGEN fission products library. For the purposes of this study, the standard 26 groups data set, KFKINR, developed at Forschungszentrum Karlsruhe, Germany, has been extended by the addition of the cross-sections of 13 important actinides and 68 most important fission products. It has been confirmed that these 68 fission products constitute about 95% of the total fission products yield and about 99.5% of the total absorption due to fission products in fast reactors. The amount of fissile material required to guarantee the criticality of the reactor during recycling schemes has also been investigated. Cumulative high active waste per ton of initial heavy metal is also calculated. Results show that the recycling of actinides and fission products in fast reactors through the atomics international reduction oxidation process results in a reduction of the potential hazard of radioactive waste.

  4. Modelling Recycling Targets

    DEFF Research Database (Denmark)

    Hill, Amanda Louise; Leinikka Dall, Ole; Andersen, Frits M.

    2014-01-01

    the existing technological, organizational and legislative frameworks may affect recycling activities. The results of the analysis show that with current best practice recycling rates, the 50% recycling rate cannot be reached without recycling of household biowaste. It also shows that all Danish municipalities...... will need to make efforts to recover all recyclable fractions, and that the increased recycling efforts of only selected municipalities will not be sufficient to reach the target.......Within the European Union (EU) a paradigm shift is currently occurring in the waste sector, where EU waste directives and national waste strategies are placing emphasis on resource efficiency and recycling targets. The most recent Danish resource strategy calculates a national recycling rate of 22...

  5. Certified Electronics Recyclers

    Science.gov (United States)

    Learn how EPA encourages all electronics recyclers become certified by demonstrating to an accredited, independent third-party auditor and that they meet specific standards to safely recycle and manage electronics.

  6. An architecture for recycling intermediates in a column-store

    NARCIS (Netherlands)

    Ivanova, M.G.; Kersten, M.L.; Nes, N.J.; Goncalves, R.A.

    2010-01-01

    Automatic recycling intermediate results to improve both query response time and throughput is a grand challenge for state-of-the-art databases. Tuples are loaded and streamed through a tuple-at-a-time processing pipeline, avoiding materialisation of intermediates as much as possible. This limits th

  7. A recycling index for food and health security: urban Taipei.

    Science.gov (United States)

    Huang, Susana Tzy-Ying

    2010-01-01

    The modern food system has evolved into one with highly inefficient activities, producing waste at each step of the food pathway from growing to consumption and disposal. The present challenge is to improve recyclability in the food system as a fundamental need for food and health security. This paper develops a methodological approach for a Food Recycling Index (FRI) as a tool to assess recyclability in the food system, to identify opportunities to reduce waste production and environmental contamination, and to provide a self-assessment tool for participants in the food system. The urban Taipei framework was used to evaluate resource and nutrient flow within the food consumption and waste management processes of the food system. A stepwise approach for a FRI is described: (1) identification of the major inputs and outputs in the food chain; (2) classification of inputs and outputs into modules (energy, water, nutrients, and contaminants); (3) assignment of semi-quantitative scores for each module and food system process using a matrix; (4) assessment for recycling status and recyclability potential; (5) conversion of scores into sub-indices; (6) derivation of an aggregate FRI. A FRI of 1.24 was obtained on the basis of data for kitchen waste management in Taipei, a score which encompasses absolute and relative values for a comprehensive interpretation. It is apparent that a FRI could evolve into a broader ecosystem concept with health relevance. Community end-users and policy planners can adopt this approach to improve food and health security.

  8. Direct regeneration of recycled cathode material mixture from scrapped LiFePO4 batteries

    Science.gov (United States)

    Li, Xuelei; Zhang, Jin; Song, Dawei; Song, Jishun; Zhang, Lianqi

    2017-03-01

    A new green recycling process (named as direct regeneration process) of cathode material mixture from scrapped LiFePO4 batteries is designed for the first time. Through this direct regeneration process, high purity cathode material mixture (LiFePO4 + acetylene black), anode material mixture (graphite + acetylene black) and other by-products (shell, Al foil, Cu foil and electrolyte solvent, etc.) are recycled from scrapped LiFePO4 batteries with high yield. Subsequently, recycled cathode material mixture without acid leaching is further directly regenerated with Li2CO3. Direct regeneration procedure of recycled cathode material mixture from 600 to 800 °C is investigated in detail. Cathode material mixture regenerated at 650 °C display excellent physical, chemical and electrochemical performances, which meet the reuse requirement for middle-end Li-ion batteries. The results indicate the green direct regeneration process with low-cost and high added-value is feasible.

  9. Quantitative analysis of damage evolution as recycled concrete approaches fatigue failure%再生混凝土疲劳损伤演化的定量描述

    Institute of Scientific and Technical Information of China (English)

    肖建清; 丁德馨; 骆行文; 徐根

    2011-01-01

    Advantages and disadvantages of several common damage defined methods were studied with test data of recycled concrete. Secondly, an inverted-S nonlinear fatigue damage cumulative model was proposed based on the three-phase law of fatigue damage evolution and physical meanings and ranges of its parameters were discussed. Eventually, the damage evolution and fatigue life of recycled concrete were investigated using the inverted-S damage model. The results indicate that many methods such as elastic modulus method, ultrasonic velocity method, maximum strain and residual strain methods are all able to represent the damage evolution law of recycled concrete. Among them, residual strain method is more suitable for its clear concept and consideration of fatigue initial damage. The fitting damage evolution equation is highly relevant with test data and the theoretically analyzed conclusion on the law of fatigue life of recycled concrete agrees well with the experimental result. Therefore, the inverted-S damage model is very suitable for the description of damage evolution of recycled concrete for its strong adaptability and high accuracy.%利用再生混凝土的疲劳试验结果,分析常用的几种损伤变量定义法的优缺点;其次,根据疲劳损伤的三阶段演化规律,提出倒S非线性疲劳累积损伤模型,给出材料参数的物理含义及取值范围;最后,基于倒S模型研究再生混凝土的损伤演化规律和疲劳寿命.分析结果表明,弹性模量法、超声波速法、最大应变以及残余应变法都能够反映再生混凝土的疲劳损伤演化规律,而残余应变法由于概念明确,考虑疲劳初始损伤,因此更为合适;拟合得到的损伤演化方程与试验数据高度相关,而理论分析得出的疲劳寿命的变化规律与试验结果也相一致;倒S模型涵盖了损伤演化规律的各种类型,具有适应性强、精度高的特点,适用于混凝土材料的损伤演化描述.

  10. Rapid, efficient and eco-friendly procedure for the synthesis of quinoxalines under solvent-free conditions using sulfated polyborate as a recyclable catalyst

    Indian Academy of Sciences (India)

    KRISHNA S INDALKAR; CHETAN K KHATRI; GANESH U CHATURBHUJ

    2017-02-01

    An efficient and inexpensive sulfated polyborate catalyst was applied for the rapid synthesis of quinoxaline derivatives from various substituted o-phenylenediamines and 1,2-diketones/α-hydroxy ketones using sulfated polyborate is described. The catalyst has the advantage of Lewis as well as Bronsted acidity and recyclability without significant loss in catalytic activity. The key advantages of the present method are high yields, short reaction times, solvent-free condition, easy workup, and ability to tolerate a variety of functional groups, which give economical as well as ecological rewards.

  11. Upgrading of recycled plastics obtained from flexible packaging waste by adding nanosilicates

    Science.gov (United States)

    Garofalo, E.; Claro, M.; Scarfato, P.; Di Maio, L.; Incarnato, L.

    2015-12-01

    Currently, the growing consumption of polymer products creates large quantities of waste materials resulting in public concern in the environment and people life. The efficient treatment of polymer wastes is still a difficult challenge and the recycling process represents the best way to manage them. Recently, many researchers have tried to develop nanotechnology for polymer recycling. The products prepared through the addition of nanoparticles to post-used plastics could offer the combination of improved properties, low weight, easy of processing and low cost which is not easily and concurrently found by other methods of plastic recycling. In this study materials, obtained by the separation and mechanical recycling of post-consumer packaging films of small size (recycled plastics (denoted as Recyclate A and Recyclate B) evidenced that they are mainly constituted of polyethylene (PE) and of a small fraction of polypropylene (PP). PE/PP incompatibility has been proved and explained in many studies reported in the literature and it represents the main reason for the unsatisfactory mechanical properties of these recycled plastics. The aim of this work was to improve the mechanical properties of these recycled polymeric mixtures by the addition of two different types of organo-modified silicates, also taking advantage of the function of nanofillers as potential blend compatibilizers. In particular, three organoclays (Dellite 67G, sepiolite PM15 and sepiolite UNISA1), differing for the morphology (lamellar or acicular) and/or the type of organic modifier, were melt compounded with the recycled materials in a twin-screw extruder. The morphological, thermal, rheological and mechanical properties of the prepared nanocomposites were extensively discussed.

  12. Assessment of Food Waste Prevention and Recycling Strategies Using a Multilayer Systems Approach.

    Science.gov (United States)

    Hamilton, Helen A; Peverill, M Samantha; Müller, Daniel B; Brattebø, Helge

    2015-12-15

    Food waste (FW) generates large upstream and downstream emissions to the environment and unnecessarily consumes natural resources, potentially affecting future food security. The ecological impacts of FW can be addressed by the upstream strategies of FW prevention or by downstream strategies of FW recycling, including energy and nutrient recovery. While FW recycling is often prioritized in practice, the ecological implications of the two strategies remain poorly understood from a quantitative systems perspective. Here, we develop a multilayer systems framework and scenarios to quantify the implications of food waste strategies on national biomass, energy, and phosphorus (P) cycles, using Norway as a case study. We found that (i) avoidable food waste in Norway accounts for 17% of sold food; (ii) 10% of the avoidable food waste occurs at the consumption stage, while industry and retailers account for only 7%; (iii) the theoretical potential for systems-wide net process energy savings is 16% for FW prevention and 8% for FW recycling; (iv) the theoretical potential for systems-wide P savings is 21% for FW prevention and 9% for FW recycling; (v) while FW recycling results in exclusively domestic nutrient and energy savings, FW prevention leads to domestic and international savings due to large food imports; (vi) most effective is a combination of prevention and recycling, however, FW prevention reduces the potential for FW recycling and therefore needs to be prioritized to avoid potential overcapacities for FW recycling.

  13. The recycling is moving

    CERN Multimedia

    GS Department

    2011-01-01

    The recycling site currently situated near building 133 has been transferred to the car park of building 156. The site is identified by the sign “RECYCLING” and the above logo. In this new, more accessible site, you will find recycling bins for the following waste: PET (recyclable plastic bottles); Aluminium cans; Nespresso coffee capsules.  

  14. Rethink, Rework, Recycle.

    Science.gov (United States)

    Wrhen, Linda; DiSpezio, Michael A.

    1991-01-01

    Information about the recycling and reuse of plastics, aluminum, steel, glass, and newspapers is presented. The phases of recycling are described. An activity that allows students to separate recyclable materials is included. The objectives, a list of needed materials, and procedure are provided. (KR)

  15. Occurrence and fate of acrylamide in water-recycling systems and sludge in aggregate industries.

    Science.gov (United States)

    Junqua, Guillaume; Spinelli, Sylvie; Gonzalez, Catherine

    2015-05-01

    Acrylamide is a hazardous substance having irritant and toxic properties as well as carcinogen, mutagen, and impaired fertility possible effects. Acrylamide might be found in the environment as a consequence of the use of polyacrylamides (PAMs) widely added as a flocculant for water treatment. Acrylamide is a monomer used to produce polyacrylamide (PAM) polymers. This reaction of polymerization can be incomplete, and acrylamide molecules can be present as traces in the commercial polymer. Thus, the use of PAMs may generate a release of acrylamide in the environment. In aggregate industries, PAM is widely involved in recycling process and water reuse (aggregate washing). Indeed, these industries consume large quantities of water. Thus, European and French regulations have favored loops of recycling of water in order to reduce water withdrawals. The main goal of this article is to study the occurrence and fate of acrylamide in water-recycling process as well as in the sludge produced by the flocculation treatment process in aggregate production plants. Moreover, to strengthen the relevance of this article, the objective is also to demonstrate if the recycling system leads to an accumulation effect in waters and sludge and if free acrylamide could be released by sludge during their storage. To reach this objective, water sampled at different steps of recycling water process has been analyzed as well as different sludge corresponding to various storage times. The obtained results reveal no accumulation effect in the water of the water-recycling system nor in the sludge.

  16. Analysis of nuclear proliferation resistance reprocessing and recycling technologies

    Energy Technology Data Exchange (ETDEWEB)

    Patricia Paviet-Hartmann; Gary Cerefice; Marcela Stacey; Steven Bakhtiar

    2011-05-01

    The PUREX process has been progressively and continuously improved during the past three decades, and these improvements account for successful commercialization of reprocessing in a few countries. The renewed interest in nuclear energy and the international growth of nuclear electricity generation do not equate – and should not be equated -with increasing proliferation risks. Indeed, the nuclear renaissance presents a unique opportunity to enhance the culture of non-proliferation. With the recent revival of interest in nuclear technology, technical methods for prevention of nuclear proliferation are being revisited. Robust strategies to develop new advanced separation technologies are emerging worldwide for sustainability and advancement of nuclear energy with enhanced proliferation resistance. On the other hand, at this moment, there are no proliferation resistance advanced technologies. . Until now proliferation resistance as it applies to reprocessing has been focused on not separating a pure stream of weapons-usable plutonium. France, as an example, has proposed a variant of the PUREX process, the COEX TM process, which does not result on a pure plutonium product stream. A further step is to implement a process based on group extraction of actinides and fission products associated with a homogeneous recycling strategy (UNEX process in the US, GANEX process in France). Such scheme will most likely not be deployable on an industrial scale before 2030 or so because it requires intensive R&D and robust flowsheets. Finally, future generation recycling schemes will handle the used nuclear fuel in fast neutron reactors. This means that the plutonium throughput of the recycling process may increase. The need is obvious for advanced aqueous recycling technologies that are intrinsically more proliferation resistant than the commercial PUREX process. In this paper, we review the actual PUREX process along with the advanced recycling technologies that will enhance

  17. Logistics Mode and Network Planning for Recycle of Crop Straw Resources

    OpenAIRE

    Zhou, Lingyun; Gu, Weidong; Zhang, Qing

    2013-01-01

    To realize the straw biomass industrialized development, it should speed up building crop straw resource recycle logistics network, increasing straw recycle efficiency, and reducing straw utilization cost. On the basis of studying straw recycle process, this paper presents innovative concept and property of straw recycle logistics network, analyses design thinking of straw recycle logistics network, and works out straw recycle logistics mode and network topological structure. Finally, it come...

  18. Protic acid immobilized on solid support as an extremely efficient recyclable catalyst system for a direct and atom economical esterification of carboxylic acids with alcohols.

    Science.gov (United States)

    Chakraborti, Asit K; Singh, Bavneet; Chankeshwara, Sunay V; Patel, Alpesh R

    2009-08-21

    A convenient and clean procedure of esterification is reported by direct condensation of equimolar amounts of carboxylic acids with alcohols catalyzed by an easy to prepare catalyst system of perchloric acid immobilized on silica gel (HClO(4)-SiO(2)). The direct condensation of aryl, heteroaryl, styryl, aryl alkyl, alkyl, cycloalkyl, and long-chain aliphatic carboxylic acids with primary/secondary alkyl/cycloalkyl, allyl, propargyl, and long-chain aliphatic alcohols has been achieved to afford the corresponding esters in excellent yields. Chiral alcohol and N-t-Boc protected chiral amino acid also resulted in ester formation with the representative carboxylic acid or alcohol without competitive N-t-Boc deprotection and detrimental effect on the optical purity of the product demonstrating the mildness and chemoselectivity of the procedure. The esters of long-chain (>C(10)) acids and alcohols are obtained in high yields. The catalyst is recovered and recycled without significant loss of activity. The industrial application of the esterification process is demonstrated by the synthesis of prodrugs of ibuprofen and a few commercial flavoring agents. Other protic acids such as H(2)SO(4), HBr, TfOH, HBF(4), and TFA that were adsorbed on silica gel were less effective compared to HClO(4)-SiO(2) following the order HClO(4)-SiO(2) > H(2)SO(4)-SiO(2) > HBr-SiO(2) > TfOH-SiO(2) > HBF(4)-SiO(2) approximately TFA-SiO(2). When HClO(4) was immobilized on other solid supports the catalytic efficiency followed the order HClO(4)-SiO(2) > HClO(4)-K10 > HClO(4)-Al(2)O(3) (neutral) > HClO(4)-Al(2)O(3) (acidic) > HClO(4)-Al(2)O(3) (basic).

  19. Energetic reuse: use of biogas from the organic matter as an alternative source to recycle plastics and supply cycle diesel engines; Reaproveitamento energetico: uso do biogas proveniente da materia organica como fonte alternativa para reciclar plasticos e alimentar motores do ciclo Diesel

    Energy Technology Data Exchange (ETDEWEB)

    Carneiro, Priscila Alves; Santos, Rodolfo Esmarady Rocha dos [Universidade Federal de Itajuba (EXCEN/UNIFEI), MG (Brazil). Centro de Excelencia em Eficiencia Energetica

    2008-07-01

    Population growth and rising purchasing power due to the economic development driving the increased production of waste generated each year. Disposal these wastes is a major economic and environmental challenge, mainly by the concentration of plastics discarded without being used, and organic matter that decompose to produce methane, a major cause of global warming. Recycling waste plastics is a solution to minimize their disposal, but high energy consumption in this process becomes expensive, losing its economically. This leads to search for new alternatives for low cost energy. In the problem of disposal of organic matter may be the solution for recycling these wastes. The decomposition of organic matter produces a fuel (biogas) as a useful source energy to generate electricity required for the recycling process, as well as its use in flex-fuel engines. This system, double-cycle diesel fuel, has advantages not require technical changes in engine design and even the compression ratio. In the condition of dual-fuel, replacement of diesel can be up to 70% due to the use of biogas, but nothing prevents the engine to fire 100% diesel. The implementation of the recycling through the use of energy of urban wastes in Itajuba and the use of biogas on fleets, will bring socio-environmental benefits to the city and consequently the region around. Among these benefits may be pointed generating direct and indirect jobs primarily in the recycling process, reduction of odors at the landfill, mitigation of greenhouse gases, reducing diesel consumption among others. Among these benefits they can be mainly pointed the generation of direct and indirect employments in the recycling process, reduction of scents in the embankment, mitigation of effect gases stews, reduction of the diesel consumption among others. The study contributes to the solution of problems related to the final destination of the residues, for the use of the electric power generated starting from the biogas

  20. Study on Recycling Metal in PCB by Heavy Medium Selection-Selectivity Milling-Acid Lixiviating Process%重选-磨细-酸浸联合工艺回收PCB中金属的研究

    Institute of Scientific and Technical Information of China (English)

    熊英禹

    2013-01-01

    采用重介质分选选择性磨细酸浸联合工艺,利用磁铁矿重介质悬浮液,对粗碎后的PCB进行分选,再利用PCB中不同塑料可磨性的不同,将其进行选择性磨细,使PCB中所含金属成分与其他组分有效分离,采用酸浸工艺将各种金属成分转移到液相中,实现金属成分的高效回收.结果表明,在PCB的粒度小于等于2.5 mm时,可使PCB中约55.26%的金属得到富集;86.08%的Au和89.21%的Ag被富集到磨细的粉末中,产品中的各种金属含量分别为:Au 0.68 kg/t,Ag 0.91 kg/t,Cu120.8 kg/t,Al2.98 kg/t,Sn28.02 kg/t.当采用350 mL浓H2SO,、浸出时间为8h,浸出温度为100℃条件下,对50 9分选后的重组分进行酸浸时,可以使Au的回收率达到89.8%,Ag的回收率达到90.2%.与其他传统工艺相比,该工艺具有回收效率高、低污染、低能耗等特点,可以作为PCBs资源化的有效手段.%This paper used heavy medium selection-selectivity milling-acid lixiviating process to recycle metal in PCBs.It used magnetite as the heavy medium,selected PCB after the coarse fragmentation,selectivity milled the PCB according to the different milling characteristics to separate the metal from other component,then,by acid lixiviating to transfer the metal into liquid phase,recycled the metal efficiently.As a result,separate efficiency could reach 55.26% when the PCB′s granularity was less than or equal to 2.5 mm; 86.08% of Au,89.21% of Ag were enriched into the powder after the selectivity milling process,and the contents of metals in the powder were Au 0.68 kg/t,Ag 0.91 kg/t,Cu120.8 kg/t,Al2.98 kg/t and Sn28.02 kg/t,respectively.Under the conditions of oil of vitriol350 mL,lixiviated time 8 h,lixiviated temperature 100 ℃,the recycle ratios of Au and Ag in 50g selected heavier part were 89.8% and 90.2%,respectively.Compared with traditional processes,the heavy medium selection-selectivity milling-acid lixiviating process had the characteristics of

  1. Selenium Recycling in the United States in 2004

    Science.gov (United States)

    George, Micheal W.; Wagner, Lorie A.

    2009-01-01

    The vast majority of selenium consumption in the United States is in dissipative uses, such as alloys, animal feeds, fertilizers, glass decolorizer, and pigments. The nondissipative use as a photoreceptor for xerographic copiers is declining. As a result of a lack of a substantial supply of selenium-containing scrap, there are no longer selenium recycling facilities in the United States. Selenium-containing materials collected for recycling, primarily selenium-containing photocopier drums, are exported for processing in other countries. Of the estimated 350 metric tons (t) of selenium products that went to the U.S. market in 2004, an estimated 300 t went to dissipative uses. An estimated 4 t was recovered from old scrap and exported for recycling.

  2. Recyclability of PET from virgin resin

    Directory of Open Access Journals (Sweden)

    Mancini Sandro Donnini

    1999-01-01

    Full Text Available Bottle grade virgin PET (polyethylene terephthalate resin was investigated through five consecutive injection molding steps to simulate recycling cycles. Tests were carried out after each recycling to evaluate degradation, crystallinity (by density and Differential Scanning Calorimetry-DSC measurements, hardness, and tensile and flexural properties. Consecutive recycling resulted in cumulative chain breaks caused by the material's contact with degrading agents such as temperature, oxygen, mechanical stresses, light, and water. In the fifth recycling step, for example, the number of carboxylic end groups, an indicator of the extent of chain-break, tripled in comparison to the initial molecule. The smaller chains that were formed fit more easily among the larger ones, thus increasing the percentage of crystalline phase in the structure. These two changes in the polymer's structure explained the recycled products' final properties, i.e., the injected samples became progressively harder and more fragile in each recycling step.

  3. Prooxidative Potential of Photo-Irradiated Aqueous Extracts of Grape Pomace, a Recyclable Resource from Winemaking Process.

    Science.gov (United States)

    Tsukada, Mana; Nakashima, Takuji; Kamachi, Toshiaki; Niwano, Yoshimi

    2016-01-01

    Our previous study revealed that aqueous extract of grape pomace obtained from a winemaking process could exert bactericidal action upon photo-irradiation via reactive oxygen species (ROS) formation. In the present study, we focused on chemical composition and prooxidative profile of the extract. Liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) analysis showed that polyphenolic compounds including catechin monomers, dimers, trimers, and polyphenolic glucosides were contained. The polyphenol rich fraction used for the LC-ESI-MS analysis generated hydrogen peroxide (H2O2) upon photo-irradiation possibly initiated by photo-oxidation of phenolic hydroxyl group. That is, reduction of dissolved oxygen by proton-coupled electron transferred from the photo-oxidized phenolic hydroxyl group would form H2O2. The resultant H2O2 was then photolyzed to generate hydroxyl radical (•OH). The prooxidative profile of the extract in terms of •OH generation pattern upon photo-irradiation was similar to that of grape seed extract (GSE) as an authentic polyphenol product and (+)-catechin as a pure polyphenolic compound, and in all the three samples •OH generation could be retained during photo-irradiation for at least a couple of hours. The prooxidant activity of the photo-irradiated extract indicated by •OH yield was more potent than that of the photo-irradiated GSE and (+)-catechin, and this was well reflected in their bactericidal activity in which the photo-irradiated extract could kill the bacteria more efficiently than did the photo-irradiated GSE and (+)-catechin.

  4. Enzymatic lignocellulose hydrolysis: Improved cellulase productivity by insoluble solids recycling

    DEFF Research Database (Denmark)

    Weiss, Noah Daniel; Börjesson, Johan; Pedersen, Lars Saaby;

    2013-01-01

    To take advantage of this effect, the amount of solids recycled should be maximized, based on a given processes ability to deal with higher solids concentrations and volumes. Recycling of enzymes by recycling the insoluble solids fraction was thus shown to be an effective method to decrease enzyme...

  5. Thorium utilization program. Quarterly progress report for the period ending May 31, 1976. [Fuel element crushing, solids handling, fluidized-bed combustion, aqueous separations, solvent extraction, off-gas studies, semiremote handling systems, alternative head-end processing, and fuel recycle design

    Energy Technology Data Exchange (ETDEWEB)

    1976-06-30

    The work reported includes the development of unit processes and equipment for reprocessing of High-Temperature Gas-Cooled Reactor (HTGR) fuel and the design and development of an integrated line to demonstrate the head end of HTGR reprocessing using unirradiated fuel materials. Work is also described on trade-off studies concerning the required design of recycle facilities for the large-scale recycle of HTGR fuels in order to guide the development activities for HTGR fuel recycle.

  6. Going for increased recycling. A social cost-benefit analysis; Inzetten op meer recycling. Een maatschappelijke kosten-batenanalyse

    Energy Technology Data Exchange (ETDEWEB)

    Warringa, G.E.A.; De Bruyn, M.; Bijleveld, M.M.

    2013-05-15

    While the environmental benefits of scenarios geared to increased recycling have been convincingly demonstrated by previous studies, the question arises whether such scenarios bring economic benefits, too. This study therefore assesses the main economic effects of increased recycling in the Netherlands, providing data that can be used to advance policy development in this area. To address the main issue we performed a social cost-benefit analysis (SCBA), a welfare-theory-based tool that can be used to chart the full range of economic impacts ('welfare impacts') of a project or policy intervention. In doing so, a broad definition of welfare is adopted, encompassing not only financial and economic consequences, but also environmental and employment impacts and so on. Using SimaPro, all the environmental interventions inventoried (including energy consumption, transport and recycling pro