Dissertationen: „Recycling processing“

1

Do, Ngoc Thanh Thuy. „Biological treatment and recycling of textile processing effluents“. Thesis, De Montfort University, 2004. http://hdl.handle.net/2086/13296.

Der volle Inhalt der Quelle

Annotation:

In the present work, a mixed culture of Pseudomonas spp. capable of decolourising a range of selected textile dyes was isolated and used to develop a continuous culture system for the treatment of textile dye effluents. The bioprocess was optimised using biomass growth supports. The presence of a carbon source such as soluble wheat starch (0.2 % w/v) in dye solution media and effluent samples enhanced decolourisation. A polymer support (polyurethane foam) was used for immobilisation of "the bacteria in the laboratory-scale bioreactor, and helped create an integrated anaerobic I aerobic condition within the foam matrix and promote degradation of azo dyes and organic compounds. The system showed high levels of decolourisation up to 98 0/0 over 12 days of continuous operation. However, toxicity levels of dye samples increased up to 65 % after anaerobic biotreatment, due to the formation of toxic aromatic amines. The continuous culture bioprocess was also combined with membrane filtration technology to improve effluent treatment. Oecolourised, filtered effluents showed great reduction in COO, BODs and toxicity levels, and were found suitable for re-use in ~yeing processes. Dyed cotton fabrics did not show any significant difference with those dyed using normal supply water. These studies show great potential for improvement of an existing industrial effluent treatment plant through the use of biomass growth supports and the combination of membrane technology. Considerable savings are foreseeable through the implementation of the process, provided effluent recycling within the textile factory is successful.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

2

Sousa, Sepulveda Azevedo Helena Paula de. „Possibilities for recycling cellulases after use in cotton processing“. Thesis, De Montfort University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391992.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

3

Koermer, Scott Carl. „The Application of Mineral Processing Techniques to the Scrap Recycling Industry“. Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/63994.

Der volle Inhalt der Quelle

Annotation:

The scrap metal recycling industry is a growing industry that plays an important role in the sustainability of a large global metal supply. Unfortunately, recycling lacks many standards, and test procedures in place for mineral processing. These standards and practices, if used in recycling, could aid recyclers in determining and achieving optimal separations for their plant.. New regulations for scrap imports into China make it difficult to obtain the metal recoveries that have been achieved in the past. In order to help scrap yards adhere to the new regulations the Eriez RCS eddy current separator system was tested in full scale. The principles this system uses, called circuit analysis, have been used by the mining industry for years, and can be used with any separation system. The Eriez RCS system surpassed the requirements of the Chinese regulations, while simultaneously increasing the recovery of metals. In order to further analyze eddy current separator circuits, tree analysis was attempted for single eddy current separators, as well as more complex circuits mimicked using locked cycle tests. The circuits used in the locked cycle test were a rougher-cleaner, a rougher-scavenger, and a rougher-cleaner-scavenger. It was found that it is possible to use tree analysis to compare different eddy current separator circuits using the same settings, however standards for this practice need to be established for it to be useful. Using the data analysis methods developed for this particular tree analysis, the rougher-cleaner-scavenger test had the best performance overall. This is the same result as the full scale testing done on the Eriez RCS system, but more testing should be conducted to confirm the data analysis techniques of calculating theoretical efficiency, recovery efficiency, and rejection efficiency.
Master of Science

APA, Harvard, Vancouver, ISO und andere Zitierweisen

4

Reuter, M. A. „The fundamental limits of recycling : from minerals processing to computer aided design of automobiles and other consumer goods /“. Link to the online version, 2006. http://hdl.handle.net/10019/1394.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

5

Mattsson, Josephie. „Technical Analysis of Flax Fiber Reinforced Polypropylene : Prerequisites for Processing and Recycling“. Thesis, Karlstads universitet, Fakulteten för teknik- och naturvetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-32352.

Der volle Inhalt der Quelle

Annotation:

Nowadays, when environmental concerns are becoming increasingly important are there great interest in natural materials and recyclability. The possibility of reusing materials with maintained mechanical properties are essential for sustainability. Today produced approximately 90,000 tons of natural fiber reinforced composites in Europe of those are 40,000 tons compression molded of which the automotive industry uses 95%. Natural fiber reinforced composites is recyclable and therefore interesting in many applications. Also, natural fiber reinforced composites is inexpensive, light in weight and shows decent mechanical properties which makes them attractive to manufactures. However, the problem with natural fiber reinforced composites is the poor adhesion between fiber and matrix, the sensitivity of humidity and their low thermal stability. Those problems could be overcome by addition of compatibilizer and reactive filler. This study will examine the technical requirement in order to develop a sustainable and recyclable biocomposite. It investigates the composition of matrix (polypropylene), fiber (flax), compatibilizer (maleic anhydride grafted polypropylene) and reactive filler (CaO) in order to obtain various combinations of stiffness, strength and processability. The two main methods used for preparing samples were compounding and injection molding. Results shows that 20 wt% flax was the optimal fiber content and that maleic anhydride grafted polypropylene is a very good compatibilizer by enhancing the strength significant. Surprisingly was the strength impaired due to the addition of CaO. The composition of 20 wt% flax, 1 wt% maleic anhydride grafted polypropylene and 79 wt% polypropylene is the technically most favorable composition.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

6

Pathak, Sandeep Kumar. „Processing, flux pinning and recycling of Y-Ba-Cu-O bulk superconductors“. Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609209.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

7

Jin, Kun. „Processing characteristics and properites [sic] of glass fiber reinforced composites from post consumer carpets“. Thesis, Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04062004-164643/unrestricted/jin%5Fkun%5F200312%5Fms.pdf.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

8

Rusendi, Dadi. „Enzymatic hydrolysis of potato processing waste for the production of biopolymers“. Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=55528.

Der volle Inhalt der Quelle

Annotation:

Biopolymers are polymers produced by certain microorganisms, that are readily degradable in the environment. These biodegradable plastics have the potential to be used as substitutes for conventional petroleum based plastic provided that the production costs can be greatly reduced. The high cost of biopolymer production is due to the cost of substrate which mainly is glucose.
The enzymatic hydrolysis of potato processing wastes was to produce glucose as a least expensive feedstock substrate for the production of biopolymers of polyhydroxybutirate (PHB) from the bacterium Alcaligenes eutrophus was studied. The enzymatic hydrolysis experiments were carried out using $ alpha$-amylase liquefaction enzymes from Aspergillus oryzae and barley-malt, and amyloglucosidase saccharification enzyme from Rhizopus.
The results indicated that the production of glucose from potato starch waste to be used as a substrate to produce biopolymers was both technically and economically feasible. A 10 to 90 ratio of barley-malt to potato starch waste gave the highest conversion of starch to glucose of 194.30 gL$ sp{-1}$ (96.56%), and the lowest liquefaction enzyme cost ($0.054) to hydrolyze one kg of potato starch waste. { it A. eutrophus /} produced PHB of 5.0 gL$ sp-1$ (76.9 % of biomass) using the glucose substrate generated from the potato starch waste.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

9

Eule, Benjamin [Verfasser]. „Processing of Co-mingled Recyclate Material at UK Material Recycling Facilities (MRF's) / Benjamin Eule“. Aachen : Shaker, 2013. http://d-nb.info/1050343115/34.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

10

Zhang, Shunli. „Recycling and processing of end-of-life electric & electronic equipment : fundamentals and applications /“. Doctoral thesis, Luleå tekniska universitet, 1999. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-16902.

Der volle Inhalt der Quelle

Annotation:

This thesis presents a concept of scrapology of end-of-life electric and electronic equipment (EOL EEE) as a basis on which to develop effective recycling techniques. Various study approaches associated with this concept are detailed in this thesis. In addition, the present work investigates materials separation techniques, in particular eddy current separation (ECS) technology. Based on our research work, a number of novel design alternatives for further developing ECS have been proposed. Major challenges encountered in processing and recycling of EOL EEE are discussed. The main results obtained in this study should be helpful in designing, implementing and improving a recycling system for EOL EEE.
Godkänd; 1999; 20061117 (haneit)

APA, Harvard, Vancouver, ISO und andere Zitierweisen

11

Haule, Liberato. „Investigation into the potential re-use of waste cotton textile garments through Lyocell processing technology (ReCell)“. Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/investigation-into-the-potential-reuse-of-waste-cotton-textile-garments-through-lyocell-processing-technology-recell(1fbdce5d-ce61-4847-89b4-15ba2a2a3b72).html.

Der volle Inhalt der Quelle

Annotation:

This project investigated the potential for the regeneration of fibres from cotton-based waste garments. The project focused on the preparation of the cotton waste pulps and assessed the suitability of the prepared material for regeneration of ReCell fibres. Mechanical processes have been developed to degrade the fabrics into a fibrous pulp potentially allowing easier fibre dissolution and purification in the fibre regeneration processes. Wet degradation and dry degradation methods were evaluated and the optimal method identified. It was established that the wet deconstruction method could produce fibres with longer length and lesser degradation of the cellulose than the dry deconstruction method. The pulp produced by wet deconstruction methods could be formed into sheets which were stronger than the pulp produced by the dry deconstruction methods. Although the cotton pulp reclaimed by the wet deconstruction methods requires extra energy to dry, it is still the most attractive processing route since the pulp will be transported to the fibre spinning plant in the form of dry cellulosic sheets. Methods for stripping off the easy care finishes in order to increase dissolution of the cellulosic garments were optimised. The stripping performance was assessed by fibre degradation, contents of the easy care finishes, and solubility of the stripped fibres in selected solvents. It was established that a combination of acidic and alkaline treatment can effect the removal of all easy care finishes and enable efficient dissolution of the pulps for fibre making. ReCell fibres were produced from 100% reclaimed material and a blend of reclaimed cotton pulp and wood pulp and structural and mechanical properties were characterised and compared to the existing Lyocell fibres. It was established that for easy separation of non-cellulosic material from the cellulose-based waste garment pulp the fibres must be modified to avoid formation of tufts. Fibre enrichment by gravity separation was recommended as a pre-requisite process prior to wet cyclone separation and the optimisation of the process was recommended for future work. ReCell processing of dyed waste garments, fibre spinning, fabric construction and wet processing of ReCell fibres have been recommended for future work. The results from this project will be used for pilot tests and later commercial production of ReCell fibres by Lenzing Company. Commercial production of ReCell fibres will contribute to the reduction of economic and environmental challenges caused by textile wastes. Moreover, the findings have identified a potential reduction of pressure on raw material for fibre production by providing an alternative source of material for regeneration of cellulosic fibres.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

12

Mohring, Violette. „Incorporation of boronic esters into polyester matrices by reactive processing for compatibilization and recycling purposes“. Electronic Thesis or Diss., Université Paris sciences et lettres, 2023. http://www.theses.fr/2023UPSLS068.

Der volle Inhalt der Quelle

Annotation:

Le poly(éthylène téréphtalate) (PET) est un des thermoplastiques les plus produits dans le monde. Sa principale utilisation est l’emballage, souvent pour des applications à usage unique. De ce fait, la gestion de la fin de vie du PET est un enjeu important. Le recyclage du PET est de plus en plus courant, mais certains défis sont toujours présents, en particulier concernant les mélanges de PET avec d’autres thermoplastiques, comme par exemple l’acide polylactique (PLA), un thermoplastique biosourcé dont la production est en augmentation. Les réseaux covalents adaptables, des réseaux de polymères contenant des liaisons chimiques dynamiques, sont une solution efficace pour améliorer la miscibilité entre thermoplastiques incompatibles, ainsi que les propriétés mécaniques de ces mélanges. Plusieurs chimies d’échange ont été développées au fil des ans pour produire des réseaux covalents adaptables. Parmi elles, la métathèse des esters boroniques est particulièrement intéressante. Les esters boroniques sont stables sur le plan thermo-oxydatif, tandis que leur métathèse est rapide sans nécessiter de catalyseur. Dans cette thèse, des esters boroniques dynamiques ont été introduits par extrusion réactive dans du PLA et du PET modifié par du glycol (PETg), utilisé comme modèle pour le PET. Les matériaux résultants ont été étudiés. Les fonctions ester du matériau, ainsi que les extrémités de chaîne, ont été utilisées à cette fin. Un diol bis(ester boronique) a été synthétisé et incorporé dans les matériaux par transestérification avec les fonctions ester de la matrice, entraînant une diminution des masses molaires des polymères. La cinétique de ce procédé, l’impact de la quantité de diol et l'influence de la nature et de la quantité de catalyseur ont été étudiés. Ensuite, l’extension de chaînes des polymères fonctionnels a été réalisée avec un allongeur de chaîne à base d'isocyanate, le poly(hexaméthylène diisocyanate) (PHDI), pour le PLA, et avec le PHDI ou un allongeur de chaîne à base d'époxy, le diglycydyl éther de bisphénol A (DGEBA) pour le PETg. Ce processus a été réalisé soit en deux étapes, avec l’introduction des esters boroniques suivie de l’extension de chaîne, soit en une étape, en se servant des bouts de chaînes des polyesters. Des mélanges de PLA et de PETg ont également été préparés et compatibilisés avec le PHDI et le diol bis(ester boronique), ou un diol ne contenant pas de fonction dynamique. Des mélanges de PLA et de PETg modifiés ont également été réalisés. Quel que soit le diol utilisé, la réaction avec le PHDI et le diol améliore la miscibilité du PLA dans le PETg, sans différence notable entre les deux diols. La présence de liaisons dynamiques confère en revanche de meilleures propriétés d'écoulement à l'état fondu. Enfin, un nouvel agent d’extension de chaîne pour le PET et les polyamines ainsi qu’un oligomère contenant des alcools et des esters boroniques pendants ont été synthétisés par polymérisation radicalaire contrôlée par transferts de chaînes réversible par addition fragmentation (RAFT)
Poly(ethylene terephthalate) (PET) is among the most produced thermoplastics. Its main application is packaging, mostly for single use. For this reason, managing the end-of-life of PET is an important issue. PET recycling is becoming increasingly common , but some issues remain, especially when it comes to blends of PET with other thermoplastics, such as poly(lactic acid) (PLA), a biobased thermoplastic whose production is increasing in the last few years. Covalent adaptable networks, which are polymer networks containing dynamic chemical bonds, have been reported as an efficient solution to improve the miscibility between incompatible thermoplastics and the mechanical properties of their blends. Several dynamic chemistries have been developed over the years to produce covalent adaptable networks. Among these, boronic ester metathesis is particularly interesting. Boronic esters are thermo-oxidatively stable, while their metathesis is rapid without the need for a catalyst. In this work, dynamic boronic esters were introduced by reactive extrusion into PLA and glycol modified PET (PETg), used as a model for PET, and the resulting materials were studied. The ester functions of the material, as well as its chain ends were used for this aim. A diol bis(boronic ester) was synthetized and incorporated in the material by transesterification with the ester groups, resulting in a decrease of the molar masses of the polymers. The kinetics of this process, the impact of the amount of diol and the influence of the catalyst nature and loading were studied. Then, the chain extension of the functional polymers was carried out with an isocyanate-based chain extender, poly(hexamethylene diisocyanate) (PHDI), for PLA, and with PHDI or an epoxy-based chain extender, bisphenol A diglycydyl ether (DGEBA) for PETg. Chain extension was performed in two steps, with boronic ester introduction followed by chain extension, or in one step, taking advantage of the chain ends of the polyesters. Blends of PLA and PETg were also prepared and compatibilized with PHDI and the diol bis(boronic ester), as well as with a non-dynamic diol. Blends of the modified material were prepared and studied as well. In all cases, the miscibility of PLA in PETg was improved by the modification with PHDI and a diol. While the presence of dynamic boronic ester functions did not significantly impact the miscibility of PLA and PETg, it seemed to induce better melt flow properties. Finally, a novel chain extender for PET and polyamines as well as an oligomer containing pendant alcohol and boronic ester functions were synthesized using radical addition fragmentation transfer (RAFT) polymerization

APA, Harvard, Vancouver, ISO und andere Zitierweisen

13

De, Jongh Willem Adriaan. „Possible applications for vacuum pyrolysis in the processing of waste materials“. Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52407.

Der volle Inhalt der Quelle

Annotation:

Thesis (MScEng)--University of Stellenbosch, 2001.
ENGLISH ABSTRACT: Current global trends in government, industry and popular OpInIOn indicate that recycling will become essential in the future. Vacuum pyrolysis is a new technology with many recycling applications that have not yet been investigated. This study is a contribution towards the better understanding of the vacuum pyrolysis process and also towards finding possible economically favourable recycling applications. A batch operated tube furnace, which allowed the controlled heating of different materials in a vacuum, was designed and built. The gases and vapours passed though a series of progressively colder vacuum traps, condensing the vapours for further study. The products from the process are charcoal, oil, an aqueous phase and noncondensable gases. The charcoal and oils' possible economic values (R2500- R5000/ton of charcoal, while the plant product oil can be sold as a low sulphur fuel, with a retail value of approximately R1.42 per litre) were determined along with the oils' chemical composition. Several possible feedstocks were studied, including intruder plant species, leather wastes, sewage sludge and a simplified representation of municipal solid waste. The three intruder plants studied were Kraalbos (Galenia africane), Scholtzbos (pteronia pallens) and Asbos (Psilocaolon absimile). These plants yielded 40%, 42% and 48% (charcoal per kilogram dry feedstock) respectively at their maximum oil yield temperatures of 380°C, 480°C and 450°C respectively. The maximum oil yields were 36%, 32% and 20% respectively (also on a dry feedstock basis). It was found that the plants with ash contents below 10% yielded commercially competitive charcoal, and that all of the plants yielded oils with heating values in the range of 24MJ/kg, containing several high value compounds. Asbos was the only plant that did not produce usable charcoal, as its ash content of 40% was double that of commercial charcoals. The leather wastes represent a previously unrecognised application of the technology that could bring huge financial rewards to the tanning industry and could provide a more environmentally friendly alternative to lined landfilling. The cost of landfilling for a medium sized tannery can be as high as RIOOO 000 a year. Apart from the volume reductions achieved (up to a factor 8) it was found that landfilling might be totally avoided if the chrome contained in the charcoal product could be extracted and reused. Sewage sludge was studied, as it is a hazardous waste that requires costly disposal in a lined landfill. It was revealed that volume reductions of up to a factor 3.5 were possible with corresponding charcoal and oil yields of 40% and 38% respectively at 500°C. It was also found that the charcoal product could be used as compost, which would then turn a costly waste into a commodity product. The oil from both the leather and sewage sludge had high energy values (26.7MJ/kg and 30.9MJ/kg respectively) and might either be sold as a bunker fuel or used in the process as a make-up heat source. The value of the oil depends on the problems posed by the oils' high nitrogen content (±5%-6%). A further study was also made of the co-pyrolysis of PVC and wood to determine the interaction between the feedstocks and as a simplified representation of municipal solid wastes. It was found that the HCI released from the PVC caused acid hydrolysis of the wood and led to lower charcoal (reduced from 32.6% to 29.7% on dry feedstock basis, at the maximum co-pyrolysis oil yield temperature of 460°C) and much higher oil yields (42.4% for the co-pyrolysis compared to 23.6% for the plant material at 460°C). An existing computer program (CEA by Gordan and McBride) was also employed in order to find explanations for some of the vacuum pyrolysis results. Although large specialist vacuum pyrolysis plants have been designed in the past (mostly to dispose of used tyre waste) it will be necessary to determine the process economics for small-scale applications if the technology is to be applied at the source of the problem. Overall vacuum pyrolysis appears to be a very promising technology that could solve many waste problems in an environmentally friendly and economically beneficial manner.
AFRIKAANSE OPSOMMING: Hedendaagse neigmgs in regenng, industrie en populêre opirue toon dat hergebruikstegnologieë al hoe meer noodsaaklik sal word in die toekoms. Vakuum pirolise is 'n nuwe tegnologie met vele moonlike hergebruik toepassings wat nog nie bestudeer is nie. Hierdie studie is 'n bydrae tot 'n dieper begrip van vakuum pirolise en ook tot die verdere soeke na nuwe toepassings vir die tegnologie. 'n Enkellading buis-oond, wat die beheerde verhitting van verskillende materiale in vakuum toegelaat het, is ontwerp en gebou. Die gevormde gasse en dampe het deur 'n progressief kouer reeks van vakuum valle beweeg waar dit vir verdere studie gekondenseer en opgevang is. Die produkte van die proses is houtskool, olie, 'n waterryke fase en nie-kondenseerbare gasse. Die houtskool en olie se moontlike waarde (R2500-R5000/ton houtskool, terwyl die plant produk olie verkoop kan word as 'n lae swael verhittings olie met 'n kleinmaat kommersieële verkoopswaarde van R1.42/1), saam met die chemiese samestelling van die olie fase, is bepaal. Die vakuum pirolise van verskeie moontlike voerstowwe is bestudeer, insluitende indringerplante, leerafval, rioolslyk en 'n vereenvoudigde voorstelling van munisipale afval. Die drie plant spesies wat bestudeer is, is: Kraalbos (Galenia africane), Scholtzbos (Pteronia pal/ens) en Asbos (Psilocaolon absimile). Die plante het opbrengste van 40%, 42% en 48% (houtskool per kilogram droë voerstof) onderskeidelik gelewer by elk van die plante se maksimum olie opbrengs temperature van 380°C, 480°C en 450°C onderskeidelik. Die maksimum olie opbrengste was 36%, 32%, 20% (olie per kilogram droë voerstof) vir die onderskeie plante. Daar is bevind dat die plante met as-inhoude van minder as 10% kommersieel kompeterende houtskool gelewer het. Dit is ook gevind dat die olie van al die plante verbrandingswaardes in die orde van 24MJ/kg lewer en dat die olies ook verskeie waardevolle chemikalieë bevat. Asbos was die enigste van die bestudeerde plante wat nie maklik bruikbare houtskool gelewer het nie. Die Asbos houtskool was minder bruikbaar as gevolg van die uiters hoë as-inhoude van tot 40% met gevolglike lae energie waarde. Die vakuum pirolise van leerafval is 'n toepassing wat nog nie voorheen ondersoek is nie. Dit kan moontlik lei tot groot finansiële voordele vir die leerlooi industrie en kan ook 'n meer omgewingsvriendelike alternatief tot belynde afval storting bied. Die koste verbonde aan die storting van leer afval van 'n medium grootte looiery kan tot R1000 000 per jaar beloop. Behalwe vir die volume verkleining behaal (tot 'n faktor 8), is daar ook gevind dat afvalstorting totaal vermy kan word as die hoë hoeveelheid chroom (12% van die houtskool) uit die houtskool verwyder en hergebruik kan word. Rioolslyk is ook bestudeer, siende dat dit ook 'n probleem afvalstof is wat teen groot koste gestort moet word. Die studie het getoon dat volume verkleinings van tot 'n faktor 3.5 en houtskool en olie opbrengste van onderskeidelik 40% en 38% by 500°C behaal kan word. 'n Ondersoek van die houtskool het getoon dat dit gebruik kan word as 'n kompos, wat dan sal beteken dat 'n probleem afvalstof verander word na 'n omgewingsvriendelike en ekonomies waardevolle produk. Die olie van beide die rioolslyk en leer het hoë energiewaardes (26.7MJ/kg en 30.9MJ/kg onderskeidelik) en kan verkoop word as verbrandingsolie of gebruik word in die vakuum pirolise proses as 'n hulp-hitte bron. Die gebruikswaarde van die olie sal baie afhang van die probleme wat deur die uiters hoë stikstof-inhoud (±5%-6%) veroorsaak gaan word. 'n Verdere studie van die ko-pirolise van PVC en hout is ook gedoen om die interaksie tussen die afvalstowwe te bestudeer en ook om as 'n vereenvoudigde voorstelling van munisipale afval te dien. Daar is gevind dat die HCI wat afkom as PVC verhit word, suur hidrolise van die houtstrukture veroorsaak en lei tot laer houtskool (verminder van 32.6% na 29.7% droë voerstofbasis, by die maksimum olie opbrengs temperatuur van 460°C) en veel hoër olie opbrengste (42.4% vir die kopirolise in vergelyking met 23.6% vir die plant materiaal by 460°C). 'n Studie van die energie wat verkry kan word uit die olie en houtskool het getoon dat 16% tot 28% meer energie verteenwoordig word deur die produkte per kilogram droë voerstof vir die ko-pirolise proses bo normale vakuum pirolise. Alhoewel groot spesialis vakuum pirolise aanlegte in die verlede ontwerp is (meestal vir die verwerking van gebruikte motor buitebande) sal dit nogstans noodsaaklik wees om die winsgewindheid van kleinermaat prosesse te bestudeer sodat vakuum pirolise by die oorsprong van die afvalstoftoegepas kan word. Dit blyk dat vakuum pirolise 'n baie belowende tegnologie IS wat verskeie afval probleme op 'n omgewingsvriendelike en ekonomies winsgewinde wyse kan oplos.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

14

Tiedemann, Jörg. „Recycling Translations : Extraction of Lexical Data from Parallel Corpora and their Application in Natural Language Processing“. Doctoral thesis, Uppsala University, Department of Linguistics, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3791.

Der volle Inhalt der Quelle

Annotation:

The focus of this thesis is on re-using translations in natural language processing. It involves the collection of documents and their translations in an appropriate format, the automatic extraction of translation data, and the application of the extracted data to different tasks in natural language processing.

Five parallel corpora containing more than 35 million words in 60 languages have been collected within co-operative projects. All corpora are sentence aligned and parts of them have been analyzed automatically and annotated with linguistic markup.

Lexical data are extracted from the corpora by means of word alignment. Two automatic word alignment systems have been developed, the Uppsala Word Aligner (UWA) and the Clue Aligner. UWA implements an iterative "knowledge-poor" word alignment approach using association measures and alignment heuristics. The Clue Aligner provides an innovative framework for the combination of statistical and linguistic resources in aligning single words and multi-word units. Both aligners have been applied to several corpora. Detailed evaluations of the alignment results have been carried out for three of them using fine-grained evaluation techniques.

A corpus processing toolbox, Uplug, has been developed. It includes the implementation of UWA and is freely available for research purposes. A new version, Uplug II, includes the Clue Aligner. It can be used via an experimental web interface (UplugWeb).

Lexical data extracted by the word aligners have been applied to different tasks in computational lexicography and machine translation. The use of word alignment in monolingual lexicography has been investigated in two studies. In a third study, the feasibility of using the extracted data in interactive machine translation has been demonstrated. Finally, extracted lexical data have been used for enhancing the lexical components of two machine translation systems.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

15

Reuter, Markus Andreas. „The fundamental limits of recycling : from minerals processing to computer aided design of automobiles and other consumer goods“. Thesis, Stellenbosch : Stellenbosch University, 2006. http://hdl.handle.net/10019.1/1331.

Der volle Inhalt der Quelle

Annotation:

Thesis (PhD (Process Engineering)--Stellenbosch University, 2006.
My applied engineering research and industrial application work of the past 20 years is presented in this dissertation. It is the conjecture of my work that only if thorough first principles knowledge of the depth of process metallurgy and recycling is available, can meaningful first principles environmental models be developed. These models can then evaluate technology, provide well argued and first principles environmental information to our tax paying consumer society as well as to legislators and environmentalists. Only through this path can one estimate the limits of recycling and its technology, hence evaluate the true boundaries of sustainability. My work with students has presently culminated in the detailed modelling and simulation of recycling systems for post-consumer goods. Notably the models are finding an application in the prediction of legally required recycling rates for automobiles. The models provide first principles arguments for less stringent EU recycling legislation and the integration of the first principles models in computer aided design tools of the automotive industry as part of a large EU 6th Framework (project managed by Volkswagen and the other European car producers). Presently these models are also being converted to model the Waste Electric and Electronic Equipment (WEEE) as well as water recycling systems respectively, both for industry in The Netherlands. This unique rigorous integration of systems engineering, reactor technology and process control theory is the basis of all my work to describe recycling systems as dynamic feedback control loops. My large body of acquired industrial knowledge renders these models practical and can hence be used by the automotive and recycling industries. The origins of this work may be found in the various cited publications and reports to industry by myself (due to my close association with industry as well as industrial experience) over the past 20 years as well as the work of my students, covering topics such as: • system optimization models for flotation, mineral beneficiation and recycling systems and applying these for design for recycling and argue for better/improved first-principles based legislation, • industrial measurement, modelling and simulation of industrial extractive process pyrometallurgical reactors as well waste incinerators and recycling plants, • various activities in other areas such as hydrometallurgy, clean and new breakthrough technology, and • process control of industrial metallurgical reactors by among others the application of artificial intelligence techniques. All the ideas of the last years have been worked out with students and have been summarized in our book: “The Metrics of Material and Metal Ecology, Harmonizing the resource, technology and environmental cycles”.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

16

Khalifa, Sajid. „Implementing flow processing with product end of life remanufacturing“. Thesis, De Montfort University, 2013. http://hdl.handle.net/2086/9503.

Der volle Inhalt der Quelle

Annotation:

This research focuses on improving the remanufacturing process efficiency by estimating the workstation utilization through identifying percentage of %Blocking and %Waiting on individual workstations within a remanufacturing flow line. It attempts to achieve this aim such that improved use of methods to overcome the effect of variability can be employed. Extensive literature review revealed the requirement of strategies to recover End of Life products due to the introduction and implementation of legislative directives demanding manufacturers to recover the End of Life resources. Upon analyzing the range of product recovery strategies, End of Life product remanufacturing has emerged as an appropriate and suitable strategy to be used since it extends the operational life of existing products without the need for the new resources required when making products. Remanufacturing is a process in which a product is disassembled to component level. Each of the components will be thoroughly examined for defects. Upon identifying defects, they will either be repaired or components will be replaced. This process in turn increases the product life span. However, remanufacturing is not widely used process applied into various industry sectors due to the fact that it is labour intensive and expensive process compared to new products. Although remanufacturing process is in infancy where small number of industry such as Automotive and Aerospace are deriving benefit from it by making effective use of remanufacturing. Ideally, the suitable manufacturing methods i.e. flow processing system, should be used to remanufacture products. However when flow processing is deployed, it is found that there are a number of factors affecting the process that if not tackled, will result in poor performance and poor efficiency of the overall remanufacturing system. This inefficiency is primarily due to the number of sources of variation found in terms of supply, product design, parts specification, operation and demand variability. Further investigation led to the characterizing the remanufacturing variability and identified ways the effect of this variability can be removed or reduced using Lean principles e.g. Single Minute Exchange of Dies and use of an appropriate manufacturing system. Based on the information revised in literature and experimental design, novel equations were developed along with a set of rules that accurately measures the workstation utilization in terms of %Blocking and %Waiting on individual workstation.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

17

Gantenbein, Daniel. „Development of mineral particle surfaces for the adsorption of pitch from wood processing and recycling of paper“. Thesis, University of Plymouth, 2012. http://hdl.handle.net/10026.1/1175.

Der volle Inhalt der Quelle

Annotation:

During the production of paper in paper mills, detrimental wood resin is released into the water circuit of the mill during the pulping process of the wood into fibres. This wood resin, termed pitch, can detrimentally deposit on the paper and on the paper machine equipment. The deposits mark the paper or can lead to a tear of the paper web involving a loss of output and a reduction in paper quality. Furthermore, the wood resinous compounds in paper mill effluents need to be reduced in order to minimise their toxic effects on water organisms. Talc has been the benchmark for many years as a mineral additive in pitch control. Since the papermaking process has changed over the years, the concept of mineral addition needs to be redefined and adopted towards the new circumstances. By understanding the fundamentals behind the adsorption of wood resin compounds from aqueous systems on to talc new mineral additives can be developed. A model for the determination of the aspect ratio of platy and rod-like particles has been developed, based on commonly available characterisations such as particle size, specific surface area and shape. It was found that the adsorption capacity of a mineral is directly proportional to its specific surface area, but only within its mineral family. Including the effect of surface hydrophilicity and hydrophobicity allowed fine tuning of the adsorption capacity of newly developed calcium carbonate grades. Furthermore, size exclusion effects, in porous, high surface area modified calcium carbonate, were seen to hinder complete coverage of the surface area by wood resin. With increasing pH, the adsorption efficiency of talc for colloidal wood resin was found to decrease. Under these alkaline conditions, which are common in modern paper making processes, talc preferentially adsorbed dissolved species. The use of the newly developed surface treated and modified calcium carbonates allowed more efficient adsorption of the colloidal fraction and, therefore, represent an efficient alternative to talc in pitch control. An increase in temperature led to an increased adsorption capacity of talc. This observation indicates the type of interaction tat controls the adsorption of hydrophobic pitch particles onto talc, i.e. the entropically favoured release of water from the hydrophobic talc surface as well as the hydrophobic methylene backbone of the hemicellulose.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

18

Uddin, Md Abbas. „Investigation of alternative colouration processing medium for textiles and novel filtration media for recycling of textile effluent“. Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/investigation-of-alternative-colouration-processing-medium-for-textiles-and-novel-filtration-media-for-recycling-of-textile-effluent(b1072010-66cc-4de3-9188-d3213aa9915a).html.

Der volle Inhalt der Quelle

Annotation:

The aim of this research was to find a suitable alternative medium of scarce freshwater for textile dyeing, and to recycle and reuse the dyebath using a combined coagulation/flocculation and novel filter media. Simulated seawater (SSW) was tested as the alternative dyeing medium with a salt concentration of 3.5% where NaCl was the major component. Fibre/dye systems of wool/acid and metal complex, wool/reactive, polyester/disperse, nylon/acid and metal complex, and acrylic/cationicdyes were tested in simulated seawater and the performances of dyed fabric were compared to conventional dyeing system of distilled water (DSW). The study found that commercial dyeing processes were robust and can be practically transferable into the seawater medium. The dye exhaustions, build-up, colour characteristics, and fastness to wash, cross-staining, rub and light were satisfactory within the dye ranges studied, which covers commercially available monochromatic Red, Yellow and Blue at light, medium and deep shades. Although SEM micrographs didn't show any presence of salt, a typical wash-off process of 1gL-1 with a non-ionic detergent at 70°C was sufficient to remove any salt that could be present on the surface or sub-surface of the dyed fabric. At room temperature, some acid and metal complex dyes were only partially soluble in SSW but this improved with gentle heating and addition of levelling agents. At dyeing temperatures near the boil, these dyes were completely soluble. A saturation limit was found to be existed for acrylic dyeing of cationic dyes over 1.0% o.m.f. depth. Although ionic interaction was the dominant mechanism for dyeing of wool, nylon and acrylic fibre with acid, metal complex and cationic dyes, the adsorption in highly saline dyebath most likely depended on the combined effects of ionic and physical/hydrophobic interaction. The resultant effect was higher dye exhaustion and consequently higher colour difference in SSW for some dyes. Reactive dyes were known to be sensitive to hardness of water but this study confirmed that reactive dye could be an alternative for deep dyeing for wool fibre in SSW. Reactive dyeing of wool followed a similar mechanism of gradual phase transfer as was observed for disperse dyeing of hydrophobic fibres over 3.0% o.m.f. depth. In contrast disperse dyeing of polyester produced consistent results for all dyes but some black dyeings produced superior colour strength in SSW. The build-up of colour in SSW compared to DSW can be different depending on the application level. To improve permeate flux by reducing membrane fouling, a number of surface modification were carried out to introduce fluorine based functional groups. Gaseous fluorination, fluorocarbon finish (FC) and plasma polymerisation were performed to introduce hydrophilic and oleophobic properties on supplied Azurtex membrane. The fluorinated Azurtex media exhibited increased wettability although it was not directly proportional to an increase in the fluorination level and treatment time. The water and oil repellency of FC and plasma treated filter media provided a reasonable level of repellency while the contact angle remained in the range of 130 to 145°. Pre-fluorination of filter media before FC treatment didn't change the water and oil repellency. Surface characterisation of Azurtex media was performed with ATR-FTIR, XPS and SEM. An increased level of fluorination at 10%F2 and prolonged exposure showed a degradation of the surface along with colour change. The fluorinated, FC treated and plasma polymerised membrane showed a typical C-F stretching vibration in the region of 1100-1350 cm-1 and weakly at 400-800cm-1. The XPS study showed a gradual increase in the -CF2 and -CF3 functionality signal intensities that resulted in imparting hydrophobicity The benchmarking of these modified Azurtex filter media against newly developed materials proved that plasma treatment improved the flow, reduced turbidity and provided an easy cake removal compared to fluorinated and FC finished filter media. Recycling of exhausted dyebath using a dual component coagulant/flocculant system of Pluspac 2000 and polyanionic Hydrosolanum protein derivative (HPSS) and microfiltration with Azurtex filter media was investigated. The process parameters such as pH and dosage of coagulants/flocculants were very critical during coagulation/flocculation for overall colour removal. The trial with model dye solution in SSW showed that the system worked in the saline environment with a relatively high concentration ratio of coagulant/flocculants but highly depends on the class and structure of dyes. Maximum colour removal was achieved for Lanaset Blue 2R and Sandolan Red MF-GRLN dye and was 89% and 61%, respectively, based on a ratio of 15:10 and 15:15 for PP2000: HPSS at pH 4.0 and 5.0, respectively. The reuse of the dyebath with combined physico-chemical and micro-filtration treatment was demonstrated to be feasible with wool/acid dye system. The colour profile of Lanaset Blue 2R and Sandolan Red MF-GRLN dyed fabrics up to 12th dyeing, with dyebath filtration undertaken after the 3rd /4th/5th reuse of the dyebath, remained comparable to dyeing in fresh baths. The colour strength, K/S, decreased after every filtration and the colour differences, DeltaE increased, but reversed in subsequent dyeing in reused dyebath. The wash and dry rub fastness of the dyed fabrics remained comparable and significant improvements in the abrasion resistance were observed.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

19

MATTOS, CLEITON dos S. „Geração de resíduos sólidos de galvanoplastia em regiões densamente povoadas - avaliação, inertização e destinação“. reponame:Repositório Institucional do IPEN, 2011. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9990.

Der volle Inhalt der Quelle

Annotation:

Made available in DSpace on 2014-10-09T12:33:36Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T14:04:02Z (GMT). No. of bitstreams: 0
Dissertação (Mestrado)
IPEN/D
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP

APA, Harvard, Vancouver, ISO und andere Zitierweisen

20

Sadan, Zaynab. „Exploring the potential for local end-processing of e-waste in South Africa“. Master's thesis, Faculty of Engineering and the Built Environment, 2019. http://hdl.handle.net/11427/30974.

Der volle Inhalt der Quelle

Annotation:

E-waste is one of the fastest-growing waste streams in the world, and South Africa (SA) is no exception. This is driven by increased consumer demand and access to electrical and electronic equipment, in addition to perceived equipment obsolescence, and rapid advancements in technology. E-waste recycling presents an opportunity in providing a source of secondary resources such as metals, plastics and glass, as well as employment and economic opportunities in both developed and developing countries. Furthermore, the diversion of this waste stream from landfills or dumps prevents additional land use and the potential negative impacts on human health and the environment. E-waste collection and upgrading is a relatively small-scale but growing industry in SA. Only 12% of e-waste generated was estimated to be recycled in 2015. Most of SA’s ewaste volumes are inaccessible due to lack of formal take-back schemes, lack of consumer awareness, as well as e-waste being kept in storage or disposed of in landfills. E-waste recyclers in SA generally carry out collection, dismantling and sorting, refurbishing, as well as pre-processing of value fractions. There is currently limited local end-processing capacity, therefore partially upgraded value fractions are prepared for export, while non-viable fractions are stockpiled or disposed of in local landfills. The business case for local end-processing of e-waste value fractions, particularly metals, does not seem feasible due to the inconsistent and insufficient volumes available. Furthermore, SA faces unique socio-economic challenges such as an unregulated yet well-established informal sector. Additionally, the legal framework presents many inhibitors for e-waste recyclers. This research study builds upon the knowledge that there is a limited understanding of the feasibility of existing e-waste end-processing technologies for implementation in the South African socio-economic and legislative context. Therefore, this research intends to find out what are the key barriers and enablers to implementing e-waste end-processing technologies in SA. Qualitative research methods were used to uncover the current challenges faced by local recyclers and other stakeholders in the value chain. The data collection thus took the form of interviews, site visits and desktop research. The findings show that the e-waste recycling industry in SA is undergoing many new developments in terms of research and investment interest, as well as the anticipated outcomes from the recent submissions of Industry Waste Management Plans (IndWMP). The industry shows potential as an emerging secondary resource economy, however, the extent to which it will mature is dependent on the organisation of its collection network as well as the development of local end-processing and manufacturing capacity. The collection network and infrastructure are currently supported by both informal and formal recyclers who provide a diversity of collection strategies and a wide network of ewaste sources. However, efforts to increase recycling rates by accessing volumes in storage and increasing consumer awareness and engagement is necessary. Besides the economies of scale required to support the development of local end-processing, alternative technologies to large-scale smelting should be considered for the SA context. While this is seen through initiatives by SA Precious Metals, end-processing technologies is still inaccessible to small and medium recyclers due to cash flow issues as well as cherry-picking of high-grade materials. Therefore, recyclers require further support in terms of dealing with non-viable fractions. This includes research and investments into technologies and business models for the recycling of low-value materials including plastics, as well as subsidies for the cost of safe disposal or treatment of these fractions. Additionally, acquisition of product markets and an increase in manufacturing capacity is necessary to accelerate industry development. The legislative framework also poses limitations on recyclers in the e-waste value chain, stemming from the legal definition of e-waste as a liability as opposed to a resource. While the legislation is unlikely to change, provisions to relieve any legal barriers should be implemented. This includes permissions for pilot projects to test new technologies, as well as legal support for smaller recyclers in the form of consultancy as well as guidelines for sustainable waste management practices should be provided. Finally, while there are many challenges present in the e-waste recycling industry today, the IndWMP offers an opportunity for collaboration between key stakeholders, including the relevant government bodies. Plans have been submitted and the outcomes of approved plans will be revealed at the beginning of 2019. The plans offer solutions for recycling subsidies, increasing the collection and recycling rates, as well as investment into technology, research and enterprise development. However, successful implementation of these plans will only occur if integration and collaboration of the local e-waste community prevail over greed and the struggle for power.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

21

Pidgeon, Elaine Fay. „The Application of Crossflow Membrane Filtration to Remediate Wheat Starch Processing Wastewater for Reuse“. Thesis, Griffith University, 2009. http://hdl.handle.net/10072/366800.

Der volle Inhalt der Quelle

Annotation:

This research project investigated the practical application of crossflow membrane filtration technology to treat wheat starch waste streams at an operating wheat starch manufacturing plant, where costs and compliance issues had a negative impact on company business. Water usage, wastewater generation, wastewater treatment and costs were investigated and membrane filtration trials undertaken. These data were utilised to determine system requirements and enable project costs to be calculated and investment alternatives compared. Water usage at the site averaged 530 kL/day (standard deviation = 194 kL/d) to 600 kL/d (standard deviation = 89 kL/d) with 8.7 kL to 9.0 kL water used per tonne flour throughput. Waste streams discharged to sewer and Liquid Fertiliser represented around 70-75% and 20% of incoming water. Three primary waste streams from the factory were combined and treated through the on-site wastewater treatment plant (WWTP). The WWTP volume was 340 m³ to 370 m³ and biogas produced off-set natural gas costs. The treatment train consisted of a head tank, preacidification tank, mix tank, anaerobic digester and aeration tank. Although designed to treat a hydraulic loading rate (HLR) of 13 m³/h and an organic loading rate (OLR) of 4.4 t/d the WWTP was regularly overloaded treating up to 26 m³/h HLR and 17.3 t/d OLR and not always operated within optimal conditions. Freshwater inputs were $1.13/kL and wastewater sewerage discharge costs were based on volume ($0.39/kL) and quality parameters such as biochemical oxygen demand measured over a five day period (BOD5) ($1.07/kg) and suspended solids (SS) ($0.42/kg). Water input costs were in the vicinity of $220,000/y and wastewater discharge costs ranged from $520,000/y to $3.2 M/y. Other disposal costs included anaerobic sludge ($169,000/y) and Liquid Fertiliser ($263,000/y). Ceramic membranes, manufactured by Fairey Industrial Ceramics, UK with different pore sizes (0.2 μm, 0.35 μm and 0.5 μm) were trialled with untreated wheat starch waste streams. Total solids, SS and chemical oxygen demand (COD) concentrations were reduced by up to 30%, 88% and 92%. Cleaning efficiencies of up to 70% were achieved with sodium hydroxide solutions. No benefits were gained by increasing transmembrane pressure (TMP) above 100 kPa. Backflushing 30 seconds every five minutes increased permeate flux. Permeate flux frequently increased over time using The application of crossflow membrane filtration technology to remediate wheat starch processing wastewater for reuse wheat starch wastewater as the feed, unlike when model starch solutions were used. Concentrated solids had a greater value as a stockfood component (average $546/d) than as biogas (average $227/d). Anaerobic effluents were treated using two different membrane types simulating sidestream MBR and submerged MBR processes. Using the side-stream MBR, effluent was progressively filtered in a multi-stage microfiltration and ultrafiltration process. Flux ranged from 51-60 L/m²⋅h and COD reduction was 84%-87%. Total nitrogen (TN) and total phosphorus (TP) were completely removed (0.1 μm membrane) and metal concentrations decreased for calcium, potassium, magnesium, aluminium, copper, iron, manganese, zinc and cadmium. Cleaning efficiencies were least for the 0.1 μm membrane and increased as membrane pore size decreased. Anaerobic permeate samples using a 0.4 μm submerged membrane contained 1.5 mg/L TP (original sample 61.9 mg/L) and 13.3 mg/L TN (original sample 350 mg/L). Bioavailable nitrogen compounds were 3.9 mg/L and 0.043 mg/L for N-Ammonia and N-Oxides respectively. Filterable reactive phosphorus concentration was 0.23 mg/L. Anaerobic permeate quality was suitable for crops moderately tolerant to salinity (0.1 μm and 0.4 Î¼m membranes), could cause foliar injury to plants and posed a low risk of complexing with cadmium in soil. TP and TN levels were suitable for irrigation use long term (100 years) (0.1 μm membrane) and short term (20 years) (0.4 μm membrane). Increased biogas generation, as a result of COD being retained by a side-stream 0.1 Î¼m membrane, could provide additional energy (43,000 GJ/quarter) with a natural gas equivalent value of around $500,000. Financial analyses were undertaken on four investment alternatives and the application involving microfiltration of untreated wastewater was identified as the least cost option for managing financial and other issues associated with wastewater discharge at the wheat starch factory.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Engineering
Science, Environment, Engineering and Technology
Full Text

APA, Harvard, Vancouver, ISO und andere Zitierweisen

22

Vialon, Thomas. „Reactive processing of polymeric materials : application to the upcycling of polyolefin blends“. Electronic Thesis or Diss., Université Paris sciences et lettres, 2023. http://www.theses.fr/2023UPSLS050.

Der volle Inhalt der Quelle

Annotation:

La production mondiale de plastiques a doublé au cours des 20 dernières années pour atteindre 391 millions de tonnes en 2021, mais seulement 8.3 % provenaient de filières de recyclage des déchets. Pour établir une industrie plastique durable et circulaire, plusieurs défis sont à relever, comme la disponibilité des collectes et des usines de recyclage, le tri des plastiques par nature chimique, ou encore la présence d’additifs et de contaminants. Plus particulièrement, les polyoléfines représentent plus de la moitié de la production annuelle de plastiques, mais il est difficile de séparer le polyéthylène (PE) et le polypropylène (PP). Le PE et le PP sont incompatibles, et leur mise en forme conjointe en fondu génère des matériaux de faible valeur présentant des propriétés mécaniques médiocres. Dans cette thèse, nous avons développé des additifs azotures de triazine qui permettent de recycler les mélanges de polyoléfines en matériaux de haute performance par extrusion réactive dans des conditions pertinentes pour l’industrie. Après une sélection dans la librairie d’azotures de triazine de structures variées, le greffage de l’additif le plus prometteur sur des polymères modèles a été étudié à l’échelle (macro)moléculaire par diverses techniques. La formation de produits de greffage par insertion C-H et l’oligomérisation du nitrène par formation de liaisons N-N ont été observées. Ces résultats ont été appliqués à l’extrusion réactive de polymères commerciaux. Dans le cas du PE, un réseau est obtenu sous l’effet de la séparation de phase de l’additif dans le fondu de polymère. Le réseau ainsi formé a pu être remis en forme, ce qui a mis en lumière la réversibilité thermomécanique des liaisons N-N réticulantes. L’extrusion réactive de mélanges de polymères incompatibles a donné des résultats similaires, grâce à la polyvalence de la réactivité du nitrène. De plus, la présence dans la fraction insoluble des deux polymères composant le mélange suggère la compatibilisation et le renforcement des interfaces. Cela se traduit par une amélioration significative de la ductilité des mélanges en traction. Enfin, les réseaux ont été recyclés mécaniquement sans perte de propriétés, et le procédé a été appliqué avec succès à des déchets plastiques ménagers
The global production of plastics has doubled in the past 20 years reaching 391 million tons in 2021, but only 8.3 % originated from post-consumer recycling streams. The sustainability and the circularity of the current plastic industry are hampered by several challenges such as the availability of curbside collection and recycling units, the difficulty of sorting polymers by nature, and the presence of additives and contaminants. In particular, polyolefins represent more than half of the annual polymer production, but it is difficult to separate post-consumer polyethylene (PE) and polypropylene (PP). PE and PP are incompatible and their joint processing in the melt results in low-value materials with poor mechanical properties. In this PhD, we developed azido-triazine additives that enable the upcycling of polyolefin blends into high-performance materials by reactive extrusion under industrially-relevant processing conditions. After a selection among a library of azido-triazines, the grafting of the most promising additive onto model polymer matrices was studied at the (macro)molecular scale using various techniques. Both grafting on the polymer chains by C-H insertion and oligomerization of the nitrene by N-N bond formation were observed. These results were applied to the reactive extrusion of commercial polymers, including PE, and the formation of a network was triggered by phase separation of the additive in the polymer matrix. The resulting crosslinked materials could be reprocessed, which highlighted the thermo-mechanical reversibility of the N-N bonds constituting the network. Reactive processing of PE-PP blends gave similar results, thanks to the versatile reactivity of the additive. In addition, incorporation of the two components into the insoluble fraction suggested compatibilization and reinforcement of the interface, associated with significantly improved tensile ductility. Finally, industrially-relevant challenges were tackled, with successful mechanical recycling of polyolefin networks without loss of properties, and efficient implementation of the solution to household plastic waste

APA, Harvard, Vancouver, ISO und andere Zitierweisen

23

Weddfelt, Erika. „Recyling potential of phosphorus in food : a substance flow analysis of municipalities“. Thesis, Linköpings universitet, Biologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-78998.

Der volle Inhalt der Quelle

Annotation:

In this study the opportunities to recycle the phosphorus contained in food handling were identified in four municipalities in the county of Östergötland. The aim was to map the flow and find out whether there were differences between municipalities with food processing industries generating large amounts of waste or phosphorus rich wastewater, or if there were differences between municipalities of different size. It was also investigated to what extent the agricultural demand of phosphorus could be covered by recycling of phosphorus from the food handling system. The result showed that between 27% and 73% of the phosphorus was found in the sludge from wastewater treatment, and that between 13% and 49% of the phosphorus was found in the centrally collected organic waste. This corresponded to 11% of the phosphorus demand on arable land in municipalities with food processing industries generating large amounts of waste or phosphorus rich wastewater, and 8% of the phosphorus demand on arable land in municipalities without such industries.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

24

ORTIZ, NILCE. „Estudo da utilizacao de magnetita como material adsorvedor dos metais Cusup(2+), Pbsup(2+), Nisup(2+) e Cdsup(2+), em solucao“. reponame:Repositório Institucional do IPEN, 2000. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10825.

Der volle Inhalt der Quelle

Annotation:

Made available in DSpace on 2014-10-09T12:44:25Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T14:07:22Z (GMT). No. of bitstreams: 1 06909.pdf: 4920910 bytes, checksum: d6e37e56c96b5266b7fcce3da3d56d3b (MD5)
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

APA, Harvard, Vancouver, ISO und andere Zitierweisen

25

CHEPCANOFF, VERA. „Separacao e recuperacao de cromio e outros elementos de valor em solucoes de trabalho e residuos industriais de galvanoplastia por troca ionica“. reponame:Repositório Institucional do IPEN, 2001. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10909.

Der volle Inhalt der Quelle

Annotation:

Made available in DSpace on 2014-10-09T12:45:26Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T13:59:37Z (GMT). No. of bitstreams: 1 07174.pdf: 7729112 bytes, checksum: 448b0bbb9302347b89a39b90929d3bf4 (MD5)
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

APA, Harvard, Vancouver, ISO und andere Zitierweisen

26

Queiroz, Ronialison Fernandes. „Uso do bagaÃo de caju como fertilizante em pomar de cajueiro estabelecido“. Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=12817.

Der volle Inhalt der Quelle

Annotation:

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
A utilizaÃÃo agrÃcola tem sido a principal opÃÃo de aproveitamento de resÃduos orgÃnicos, urbanos ou industriais, minimizando o descarte a cÃu aberto ou em aterros controlados e sanitÃrios, com a consequente elevaÃÃo na vida Ãtil dos mesmos e, beneficiando a reciclagem de nutrientes, com melhoria da produtividade e sustentabilidade dos sistemas agrÃcolas. Entretanto, sÃo necessÃrios estudos de avaliaÃÃo especÃficos dos resÃduos existentes e de seus efeitos nos solos, a fim de que se possa ter o mÃximo benefÃcio, sem comprometer o ambiente. Com o objetivo de avaliar os efeitos do resÃduo do processamento do pedÃnculo do caju (bagaÃo de caju), na presenÃa e na ausÃncia de adubaÃÃo mineral, sobre a fertilidade do solo, nutriÃÃo e produtividade das plantas e qualidade dos frutos e pseudofrutos de cajueiro, foi desenvolvido um experimento em pomar estabelecido de cajueiros, localizado no municÃpio de Pacajus, CE. Os tratamentos consistiram da combinaÃÃo de cinco doses do bagaÃo de caju (0; 3,3; 6,6; 9,9 e 13,2 t ha-1, em base seca, correspondentes a 0; 5,3; 10,6; 15,9 e 21,4 t ha-1 do bagaÃo apÃs prÃ-secagem ao sol (considerando-se cerca de 38% de H2O no resÃduo) na ausÃncia e presenÃa da adubaÃÃo mineral. O delineamento experimental utilizado foi em blocos ao acaso (DBC), sob esquema fatorial 5x2. Foram feitas avaliaÃÃes quÃmicas do solo, aos 6, 12, 18, 24 e 30 meses apÃs aplicaÃÃo do bagaÃo de caju. Na planta foram avaliadas a produÃÃo, composiÃÃo quÃmica das folhas e frutos, anualmente. Houve incremento nas concentraÃÃes de P, K e H + Al no solo; houve aumento dos teores foliares de N, P e Zn; a qualidade dos pseudofrutos foram melhoradas e a produÃÃo de frutos foi afetada positivamente na segunda safra aos dezoito meses apÃs a aplicaÃÃo do bagaÃo de caju. De modo geral o efeito da aplicaÃÃo do bagaÃo como adubo orgÃnico sobre a fertilidade do solo, estado nutricional das plantas, qualidade dos pedÃnculos e produtividade, foi linear crescente, sendo necessÃrio a realizaÃÃo de novos estudos, incluindo doses mais elevadas ou reaplicaÃÃes para a determinaÃÃo das doses Ãtimas econÃmica e fÃsica.
Organic, domestic and industrial residues have recently been used as agricultural fertilizer, providing many advantages such as minimizing the problem of garbage left in the open or in controlled landfills, increasing the usage period of the landfills as well as increasing the nutrients recycling, besides improving the productivity and sustainability of agricultural systems. However, evaluation studies of residues and their effects on the soils, mainly concerning the maximization of their benefits and environmental problems are meager. The aim of the present study was to assess the potential of industrial residues of cashew apples, with and without mineral fertilization, on the soil fertility, plant production and quality of fruits and apples of cashew nut adult plants in field conditions. The experiment was conducted in an orchard located at the Pacajus County, in the CearÃ state (Brazil). Treatments were as follows: five dosages of dried cashew bagasse (metric ton per hectare): 0; 3.3; 6.6; 9.9 and 13.2, corresponding to 0; 5.3; 10.6; 15.9 and 21.4 t ha1 of bagasse before sun drying (equivalent to approximately 38.0% of humidity). Treatments included the presence and the absence of additional mineral fertilizers. The experimental design was in randomized blocks with a factorial of 5x2. The soil chemical analyses were carried out at 6, 12, 18, 24 and 30 months after the bagasse incorporation. Parameters annually assessed were plant production (fruits and apples), chemical composition of leaves and fruits. Results showed increase in concentrations of P, K and H+Al in soil, besides increases of N, P and Zn in leaves. Apples exhibited better quality and the fruit production increased 18 months after the bagasse application. The results showed that the incorporation of bagasse in soil as an organic fertilizer improved the nutritional status of cashew plants, the quality of apples and the productivity in an increasing linear function, although more studies involving higher dosages of bagasse as well as higher number of replications are suggested in order to determine the best economical and physical dosages

APA, Harvard, Vancouver, ISO und andere Zitierweisen

27

Chatzikos, Nikolaos. „Influence of fluxing agent on the quality of recycled Aluminium billets“. Thesis, KTH, Materialvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231166.

Der volle Inhalt der Quelle

Annotation:

The quality of aluminium cast billets is highly dependent on the cleanliness of the material. Hydro Extruded Solutions are casting billets in Sjunnen that are delivered for extrusion within the same company. In order to produce extruded profiles of high quality and also maintain the pressing tools, it is a good method to keep the billets as free from inclusions as possible. A fluxing agent in form of salt compounds is used to purify the material during melting, but also to protect it from further oxidation. Another task of fluxing agents is to minimize the aluminium amount in the dross phase. The purpose of this project was to investigate if the fluxing agent that is used by the cast house is having any impact on the quality of the billets. Therefore, for that purpose, samples with a variating amount of fluxing agent were processed by the cast house in order to be investigated. These samples were investigated with the Optical Microscopy-method in order to determine the area fraction of non-metallic inclusions inside them. The results did not reveal any significant difference in the quality of the different samples since most samples obtained a low OM-index after the investigation. That can be explained by the type of scrap that was used since new scrap is usually very clean and contains smaller amounts of inclusions.
Kvaliteten hos aluminiumgöt är starkt beroende av renheten i materialet. Hydro Extruded Solutions gjuter rundgöt i Sjunnen, som sedan levereras för strängpressning inom samma företag. För att producera strängpressade profiler av hög kvalitet och även upprätthålla pressverktygen, är en bra metod att hålla göten så fria från inneslutningar som möjligt. Ett flussmedel, i form av saltföreningar, används för att rena materialet under smältningen, men också för att skydda den från vidare oxidation. En annan uppgift som flussmedel har är att minimera mängden aluminium i slaggfasen. Syftet med detta projekt var att undersöka om flussmedelet som används av omsmältverket har någon inverkan på götkvaliteten. Därför, för detta ändamål har prover med en varierande mängd av flussmedel tillverkats i omsmältverket för att bli undersökta. Dessa prover undersöktes med den Optiskt Mikroskopiska-metoden för att bestämma areafraktionen av icke-metalliska inneslutningar inuti dem. Resultaten avslöjade inte någon signifikant skillnad i kvaliteten hos de olika proverna eftersom de flesta prover erhöll ett lågt OM-index efter undersökningen. Detta kan förklaras av vilken typ av skrot som användes, då process-skrot oftast är väldigt rent och består av mindre mängder innseslutningar.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

28

SORDO, FILHO GIOVANNI del. „Estudo da adsorção de íons metálicos em caulinita para água de reuso“. reponame:Repositório Institucional do IPEN, 2015. http://repositorio.ipen.br:8080/xmlui/handle/123456789/26394.

Der volle Inhalt der Quelle

Annotation:

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-06-22T14:16:56Z No. of bitstreams: 0
Made available in DSpace on 2016-06-22T14:16:56Z (GMT). No. of bitstreams: 0
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

APA, Harvard, Vancouver, ISO und andere Zitierweisen

29

Li, Ruihua. „Single polymer composites made of slowly crystallizing polymer“. Diss., Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/33925.

Der volle Inhalt der Quelle

Annotation:

Composites are widely used in an increasing number of applications in diverse fields. However, most traditional composite materials are difficult to recycle. Because of their enhanced recyclability, thermoplastic single-polymer composites (SPCs), i.e., composites with fiber and matrix made from the same thermoplastic polymer, have attracted much attention in the recent years. High-performance polymer fibers in combination with same polymer matrices would lead to a fully recyclable single polymer composite that has major ecological advantages. However, because a single polymer is involved in the composite, thermoplastic SPCs manufacturing presents a unique set of technical problems, and different approaches from those in standard composites manufacturing are frequently needed. Two specific issues in SPCs manufacturing are how to produce distinct forms of the same polymer and how to consolidate them. So far, most investigations have been reported on a single-component hot compaction method and two-component molecular methods. However, in these methods, either the processing window is too narrow or some impure materials are introduced into the system. The key issue in thermoplastic SPCs processing is how to melt-process the matrix without significantly annealing or even melting the fiber. To overcome the above drawbacks in existing SPCs processing, particularly to widen the SPCs processing temperature window and to purify the SPCs, a novel SPCs manufacturing process utilizing the characteristics of slowly crystallizing polymers was developed and investigated. Highly oriented and highly crystalline fibers made of a slowly crystallizing polymer are mixed with the amorphous form of the same polymer and then consolidated together under heat and pressure. In this dissertation research, two slowly crystallizing polymers, poly(ethylene terephthalate) (PET) and poly(lactic acid) (PLA), were used as model systems for SPCs processing.. To study the deformation and failure mechanisms of PET and PLA SPCs, the SPCs were characterized using tensile test, tearing test, impact test, SEM, optical microscopy, and other methods. The change of crystallinity and orientation of the material forms during SPCs processing were characterized by DSC and XRD. The effects of major process conditions on the performance of the SPCs were studied. It was found that the processing temperature played a profound role in affecting the fiber-matrix bonding property. The compression molded SPCs exhibited enhanced mechanical properties. For the PET SPCs with 45% by weight fiber content the tensile strength is four folds of that of non-reinforced PET. After reinforcement, the tearing strength of the PLA SPCs is almost an order higher than that of the non-reinforced PLA. The fusion bonding behavior of two crystallizable amorphous PET sheets was also studied. Several characterization methods including SEM, TEM and polarized microscopy (either on etched or on non-etched samples) were used to observe interfacial bonding morphology of the crystallizable amorphous PET sheets. For a bonded sample, a layer of transcrystals with a thickness of 1-2 Ým was found right at the interface. A secondary but much larger zone with a distinct morphology was observed outside the transcrystal layer. With increase of the heating time, the width of the whole interfacial region decreases. The interfacial morphology was found to significantly affect the interfacial bonding quality. The testing results further indicated that high bonding temperature with an appropriate holding time promotes interfacial bonding of two crystallizable amorphous PET.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

30

Cabrera, Alvino Géraldine. „Eco-design and processing of recycled multilayer/multiphase polymer materials : Structure-properties-process relationship“. Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI076.

Der volle Inhalt der Quelle

Annotation:

Dans un contexte d’économie circulaire, les premiers travaux de la thèse ont été consacrés à l’étude de l’aptitude à la mise en forme de films souples recyclés provenant de déchets agricoles d’enrubannage et d’horticulture. Ces films multicouches contiennent initialement un additif conférant au produit final un caractère collant. Lors de leur recyclage, cet additif est toujours présent et migre à la surface. Un accent particulier a été dédié à la compréhension et l’étude des mécanismes de migration de cet additif en fonction de l’architecture moléculaire des polyéthylènes utilisés ayant des taux de branchements différents. Pour ce faire, des mélanges modèles, avec ou sans charges minérales, ont été élaborés. Outre des études morphologiques et microstructurales, des méthodologies expérimentales originales ont été mises en place pour étudier la cinétique de migration/diffusion avec des dispositifs tribo-rhéométriques et de suivi du "tack" en surface des films. Quant au comportement rhéologique en cisaillement et en élongation, il est influencé par la présence de cet additif. La deuxième partie de cette étude a été consacrée à l’appréhension des réalités de l’activité du recyclage d’autres films mutlicouches souples à base de polypropylène et polyéthylène. Compte tenu de la complexité de ces gisements, nous avons choisi d’étudier des mélanges modèles équivalents en leur associant des compatibilisants de nature physique. L’influence de ces derniers sur les propriétés rhéologiques, morphologiques et mécaniques a été ensuite évaluée. Cette étude a été ensuite transposée à des systèmes multiphasés post usage. Les derniers travaux ont été dédiés à une approche prospective. Il s’agit d’aller de l’éco-design à l’élaboration de multi-micro/nanocouches facilement recyclables. L’originalité de cette étude consiste à limiter le nombre de constituants, à réduire/contrôler les épaisseurs des couches et éviter l’utilisation des couches de liants. Enfin, leurs propriétés rhéologiques, morphologiques et mécaniques ont été évaluées en fonction des cycles de recyclage mécanique
In the context of a circular economy, the first works of the thesis were devoted to the study of the processing ability of recycled flexible films from agricultural bale wrapping film's waste. These multilayer films initially contain an additive that gives the final product a sticky character. During recycling, this additive is still present and migrates to the surface. A particular emphasis has been placed on understanding and studying the migration mechanisms of this additive according to the molecular architecture of the polyethylenes used with different branching content. Model blends, with or without mineral fillers, were prepared for this purpose. In addition to morphological and microstructural studies, original experimental methodologies have been set up to study the migration/diffusion kinetics with tribo-rheometry and film surface's "tack" monitoring devices. As for the rheological behaviour in shear and elongation, it is influenced by the presence of this additive. The second part of this study was devoted to understanding the realities of the recycling activity of other polypropylene- and polyethylene-based multilayer films. Given the complexity of these materials, we chose to study equivalent model blends by combining them with physical compatibilizers. The influence of the latter on the rheological, morphological and mechanical properties was then evaluated. This study was then transposed to postconsumption multiphase systems. The last studies were devoted to a future-oriented approach. This involves going from eco-design to the development of easily recyclable multimicro/ nanolayers. The originality of this study consists in limiting the number of constituents, reducing/controlling the thickness of the layers and avoiding the use of tie-layers. Finally, their rheological, morphological and mechanical properties have been evaluated according to number and type of mechanical recycling cycles

APA, Harvard, Vancouver, ISO und andere Zitierweisen

31

AMORIM, ALDO S. de. „Análise crítica da viabilidade econômica e ambiental do processo de reciclagem de resíduos de construção civil no âmbito de um município“. reponame:Repositório Institucional do IPEN, 2016. http://repositorio.ipen.br:8080/xmlui/handle/123456789/26806.

Der volle Inhalt der Quelle

Annotation:

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-11-11T11:09:07Z No. of bitstreams: 0
Made available in DSpace on 2016-11-11T11:09:07Z (GMT). No. of bitstreams: 0
Este trabalho apresenta uma análise da viabilidade econômica e ambiental do processo de reciclagem de Resíduos de Construção Civil em um município. Utilizou-se como base o Município de Guarulhos onde foi efetuado um levantamento das quantidades de resíduos de construção civil produzidos, seu gerenciamento e o processo de reciclagem e reutilização dos agregados reciclados produzidos. O Município de Guarulhos implantou o primeiro Ponto de Entrega Voluntária (PEV) de resíduos em 2003 e, de forma ininterrupta, vem aumentando a disponibilidade desses pontos a população, possuindo 17 pontos em 2014. Inicialmente planejados para receber apenas resíduos provenientes de construção civil, tornaram-se pontos onde a população destina inúmeros resíduos sólidos não orgânicos. A empresa de pública responsável por obras na cidade, PROGUARU, possuiu uma Usina de Reciclagem de Resíduos de Construção Civil (URE) que produz agregados reciclados para uso em manutenções e pavimentação, além de fornecer material para utilização na Fábrica de Pré-Moldados da Prefeitura, fechando um ciclo de captação, processamento e reutilização dos Resíduos de Construção Civil no município. Foram desenvolvidos dois modelos que incluem no cálculo econômico do processo de reciclagem de Resíduos de Construção Civil de um município, a economia obtida com a diminuição do descarte irregular e com a substituição de agregados naturais pelos agregados reciclados produzidos pela PROGUARU. No período de 2003 a 2014, os Pontos de Entrega Voluntária receberam 296.210,11 . 10³ kg de resíduos totais, e enviou 214.910, 57 . 10³ kg de Resíduos de Construção Civil para a URE. O lucro anual do sistema incluindo o custo dos terrenos (PEV e URE) foi de R$ 3,50 por habitante, e desprezando o valor dos terrenos foi de R$ 5,02 por habitante. O trabalho de pesquisa comprova a viabilidade econômica da reciclagem, além dos ganhos ambientais pela diminuição dos descartes irregulares e economia de recursos naturais.
Tese (Doutorado em Tecnologia Nuclear)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

APA, Harvard, Vancouver, ISO und andere Zitierweisen

32

Silveira, André Vicente Malheiros da. „APLICAÇÃO DA SEPARAÇÃO ELETROSTÁTICA NA RECICLAGEM DE RESÍDUOS POLIMÉRICOS E BATERIAS DE ÍON DE LÍTIO“. Universidade Federal de Santa Maria, 2016. http://repositorio.ufsm.br/handle/1/8806.

Der volle Inhalt der Quelle

Annotation:

Fundação de Amparo a Pesquisa no Estado do Rio Grande do Sul
The increasing industrial development results in a large consumption of products and materials. Among them, stand out the polymeric materials, due to their versatility and low cost, and electrical and electronic equipment (EEE), such as mobile phones and their batteries. In this scenario, an efficient and environmentally friendly recycling technology has a great importance. Therefore, this study presents an alternative to the mechanical recycling of these wastes. The separation of the polymeric mixtures was performed using the triboelectrostatic separation process. The components of lithium-ion batteries were recovered by a corona electrostatic separation process. In polymeric waste processing, the methodology employed was the characterization, washing, drying, comminution, secondary washing, secondary drying, tribocharging and electrostatic separation of the different polymeric blends (HDPE / PP, LDPE / PP and PET / PVC). The variables studied were the tribocharging mechanism, the relative humidity, the tribocharging residence time, the angle of the deflector, the distance of the static electrode, the electrode voltage and the rotation of the roll. In lithium ion batteries waste processing, the methodology employed was the characterization, comminution, drying, particle size separation and electrostatic separation. The selected parameters were the electrodes voltage, cylinder rotation, the distance of the static electrode and the angle of the deflector of the collector. For the polymeric waste processing the best results were: low relative humidity, tribocharging residence time of 5 minutes, angle of the deflector of 2.5 °, the distance of the static electrode of 3 cm, voltage of 30 kV and speed rotation 10 rpm. With these parameters, was obtained the recovery of 92.8% of PP (purity of 95.7%) and 95.9% of HDPE (purity of 93.1%). In the separation of PP and LDPE, was obtained a PP recovery of 90.2% (purity 93.8%) and a LDPE recovery of 94.2% (purity of 90.8%). Also, was achieved a recovery of 96.8% of PET (purity of 95.9%), and recovery of 95.9% for PVC (purity of 96.8%). For lithium ion batteries waste processing the best conditions were: rotation speed of 20 rpm, voltage of 25 kV, distance of the static electrode 6 cm and angle of the deflector 0 °. Through this process, was obtained a conductive fraction with 98.98% of metals content and a nonconductive fraction with 99.6% of polymer. The characterization of the batteries showed the batteries heterogeneity, being the electrostatic separation efficient to the different models tested. Therefore, the application of electrostatic separation is a promising method and efficient to recycling of polymer waste and lithium ion batteries waste. The studied process enabled a significant recovery of the components with a high purity.
O crescente desenvolvimento industrial acarreta em um grande consumo de produtos e materiais. Entre eles, destacam-se os materiais poliméricos, devido à sua versatilidade e baixo custo, e os equipamentos elétricos e eletrônicos (EEE), tais como os telefones celulares e suas baterias. Nesse cenário, tecnologias de reciclagem eficientes e ambientalmente aceitáveis tem uma grande importância. Diante disso, o presente trabalho apresenta uma alternativa para a reciclagem mecânica destes diferentes resíduos. A separação das misturas poliméricas foi realizada através do processo de separação triboeletrostática. Já os diferentes componentes das baterias de íon de lítio foram recuperados por um processo de separação eletrostática por efeito corona. No processamento dos resíduos poliméricos, a metodologia empregada consistiu na caracterização, lavagem, cominuição, lavagem e secagem secundária, tribocarregamento e separação eletrostática das diferentes misturas poliméricas (PEAD/PP, PEBD/PP e PET/PVC). As variáveis estudadas foram o mecanismo de tribocarregamento, a umidade relativa do ar, tempo de tribocarregamento, ângulo do defletor, distância do eletrodo de atração, tensão dos eletrodos e a rotação do rolo. No processamento das baterias de íon de lítio, realizaram-se a caracterização das baterias, cominuição, secagem, separação granulométrica e separação eletrostática. Os parâmetros selecionados foram a tensão dos eletrodos, rotação do rolo, distância do eletrodo de atração e o ângulo do defletor do coletor. Para o processamento dos resíduos poliméricos os melhores resultados foram: umidade relativa do ar de ± 42%, tempo de tribocarregamento de 5 minutos, ângulo do defletor de 2,5°, distância do eletrodo de atração de 3 cm, tensão de 30 kV e velocidade de rotação de 10 rpm. Com esses parâmetros, obteve-se a recuperação de 92,8% de PP (pureza de 95,7%) e 95,9% de PEAD (pureza de 93,1%). Na separação de PP e PEBD, obteve-se uma recuperação de PP de 90,2% (pureza de 93,8%), e uma recuperação de PEBD de 94,2% (pureza de 90,8%). Também, conseguiu-se uma recuperação de 96,8% de PET (pureza de 95,9%), e de 95,9% de PVC (pureza de 96,8%). Para a reciclagem de baterias de íon de lítio as melhores condições foram: velocidade de rotação de 20 rpm, tensão de 25 kV, distância do eletrodo de atração de 6 cm e ângulo do defletor de 0°. Através deste processamento, obteve-se uma fração condutora com 98,98% de metais e uma fração não condutora com 99,6% de polímeros. A caracterização das baterias demonstrou uma heterogeneidade desse tipo de resíduo, sendo o processo de separação eletrostática eficiente para os diferentes modelos testados. Sendo assim, a aplicação da separação eletrostática se mostrou um método eficiente e promissor para a reciclagem de resíduos poliméricos e de resíduos de baterias de íon de lítio. O processo estudado possibilitou a obtenção de uma expressiva recuperação dos componentes com uma alta pureza.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

33

Snyman, Dirk Petrus. „Outomatiese genreklassifikasie vir hulpbronskaars tale / Dirk Snyman“. Thesis, North-West University, 2012. http://hdl.handle.net/10394/10209.

Der volle Inhalt der Quelle

Annotation:

When working in the terrain of text processing, metadata about a particular text plays an important role. Metadata is often generated using automatic text classification systems which classifies a text into one or more predefined classes or categories based on its contents. One of the dimensions by which a text can be can be classified, is the genre of a text. In this study the development of an automatic genre classification system in a resource scarce environment is postulated. This study aims to: i) investigate the techniques and approaches that are generally used for automatic genre classification systems, and identify the best approach for Afrikaans (a resource scarce language), ii) transfer this approach to other indigenous South African resource scarce languages, and iii) investigate the effectiveness of technology recycling for closely related languages in a resource scarce environment. To achieve the first goal, five machine learning approaches were identified from the literature that are generally used for text classification, together with five common approaches to feature extraction. Two different approaches to the identification of genre classes are presented. The machine learning-, feature extraction- and genre class identification approaches were used in a series of experiments to identify the best approach for genre classification for a resource scarce language. The best combination is identified as the multinomial naïve Bayes algorithm, using a bag of words approach as features to classify texts into three abstract classes. This results in an f-score (performance measure) of 0.929 and it was subsequently shown that this approach can be successfully applied to other indigenous South African languages. To investigate the viability of technology recycling for genre classification systems for closely related languages, Dutch test data was classified using an Afrikaans genre classification system and it is shown that this approach works well. A pre-processing step was implemented by using a machine translation system to increase the compatibility between Afrikaans and Dutch by translating the Dutch texts before classification. This results in an f-score of 0.577, indicating that technology recycling between closely related languages has merit. This approach can be used to promote and fast track the development of genre classification systems in a resource scarce environment.
MA (Linguistics and Literary Theory), North-West University, Potchefstroom Campus, 2013

APA, Harvard, Vancouver, ISO und andere Zitierweisen

34

Parente, Ricardo Alves. „Elementos estruturais de plástico reciclado“. Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-19072006-095941/.

Der volle Inhalt der Quelle

Annotation:

Nesta pesquisa, fez-se uma abrangente reunião da literatura existente, apresentando um resumo histórico da evolução dos plásticos, enfocando o estado da arte e os avanços obtidos com o emprego desses materiais na construção civil, com função estrutural. É feita uma revisão sobre a estrutura química dos plásticos mais conhecidos, apresentando os mecanismos moleculares que provocam os fenômenos dependentes do tempo, e de que forma as suas propriedades podem ser alteradas. Este trabalho também analisa os diversos modelos de previsão do comportamento viscoelástico, além de fazer uma comparação entre os modelos de Maxwell, Kelvin-Voigt e Associado e os dados experimentais, mostrando aqueles que mais se adequam ao comportamento do material plástico. São discutidos alguns aspectos pertinentes a um Projeto de Engenharia e, posteriormente, apresentados alguns conceitos e considerações específicos a um projeto de estruturas de material plástico. Os tipos de processamento mais utilizados são apresentados e, para cada um deles, quais as aplicações a que se destinam e qual a sua influência nas características do produto final. Tratando-se do plástico reciclado, é de fundamental importância o conhecimento e o entendimento do processo de reciclagem. Além da apresentação dos tipos de reciclagem, é feita uma análise do cenário local e global do mercado dos plásticos reciclados. Ao fim deste trabalho, pôde-se concluir que o mercado dos elementos estruturais de plástico reciclado é um nicho a ser explorado e, como a pesquisa sobre o tema é ainda incipiente, há muito a ser estudado, pesquisado e, posteriormente, desenvolvido. Pode-se afirmar que a baixa rigidez do plástico reciclado frente aos materiais de construção tradicionais é a sua maior deficiência. O seu comportamento viscoelástico, dependente do tempo, e a sua sensibilidade à variação de temperatura tornam complexo o dimensionamento com esse material, desencorajando o seu emprego pelos projetistas de estruturas. Desde que sejam desenvolvidas formas de se contornar essas deficiências, como a adição de fibras, o emprego de armaduras de protensão nos elementos estruturais e a aplicação de aditivos, o emprego do plástico reciclado como elemento estrutural mostra-se não só tecnicamente viável, como bastante também promissor
This work deals with the employment of plastic materials in structures of civil construction. First, a reunion of existent literature is performed, emphasizing the state of art and the obtained advances in this area. A resume about the chemical structures of plastics is done, presented, considering the molecular mechanisms that cause the time-dependent behavior. This work also analyzes the several prediction models of viscoelasticity and compares the models of Maxwell, Kelvin-Voigt, Associated and experimental data, looking for those that best adequate with the plastic behavior. Some aspects involving an engineering project are discussed and, after, some specific concepts and ideas about plastic structures are presented. This work also considers the processing of plastics and its influence on the characteristics of manufactured product. Beyond the ways of plastic recycling, a local and global analysis of recycled plastic market are presented. It can be concluded that the recycled plastic structures market needs to be explored and as the research is novel, there is a lot to be studied, researched and, after, developed. The low stiffness is the worst characteristic of plastics and the time-dependent behavior and the temperature sensibility make the design complex, not encouraging the employment by engineers. If these problems are crossed, with fibers, additions or the pos-tension of reinforcement, the recycled plastic as structural element become technically viable and a reality in a brief future

APA, Harvard, Vancouver, ISO und andere Zitierweisen

35

Gonçalves, Marques Gabriela. „Effet du recyclage mécanique sur la modification structurale et le comportement mécanique du PET vierge et renforcé choc“. Electronic Thesis or Diss., Lyon 1, 2024. http://www.theses.fr/2024LYO10273.

Der volle Inhalt der Quelle

Annotation:

Le recyclage est aujourd’hui l’une des possibilités pour limiter l’impact environnemental des déchets plastiques. Dans ce contexte, le polyéthylène téréphtalate (PET) a une importance majeure, étant le polymère le plus recyclé au monde. Malgré les efforts déployés pour le recyclage de ce matériau, de nombreux défis techniques freinent encore son développement industriel. Ce travail de recherche vise à mieux comprendre les limites du recyclage mécanique du PET et à proposer des solutions techniques innovantes pour les dépasser. L’ambition de ce projet de thèse est d’étendre l’utilisation des modifiants choc à base de dérivés acryliques pour améliorer les performances mécaniques du PET, tout en étudiant leur potentiel de recyclage. La première phase expérimentale de cette recherche s’attache à clarifier la relation entre la modification structurale induite par les cycles successifs de transformation sur la réponse mécanique du PET recyclé (rPET). Ensuite, l’introduction d’additifs peut être évaluée. Deux stratégies de renforcement avec des modifiants choc, réactives ou non réactives, sont étudiées et leurs performances comparées. Enfin, le potentiel de retraitement des mélanges produits est également identifié. La contribution de la présence de la phase élastomère dans les différentes modifications structurales observées précédemment peut aider à mieux comprendre leur action et les différents mécanismes en jeu. Tout au long de ce travail, les effets sur les étapes de fabrication et sur la réponse rhéologique des mélanges sont discutés. Les transitions thermiques et la morphologie des mélanges guident également leur compréhension. Enfin, des aspects tels que le vieillissement physique de la matrice PET sont pris en compte. L'objectif principal de ce travail est donc d'élargir les possibilités de recyclage du PET, en le facilitant sans affecter son impact environnemental
Recycling is today one of the possibilities for limiting the environmental impact of plastic wastes. In this context, polyethylene terephthalate (PET) is in the spotlight, being the most recycled polymers in the word. Despite the efforts spent in recycling this material, many technical challenges still restrain its industrial development. This research work intends to better understand the limitations of the mechanical recycling of PET and to offer innovative technical solutions for these drawbacks. The ambition of this project is to extend the use of acrylic-based impact modifiers to boost the mechanical performances of PET while studying their recycling potential. The first experimental phase of this research focus on clarifying the relationship between structural modification caused by successive reprocessing cycles and the mechanical response of recycled PET (rPET). Then, the introduction of low concentration of additives is assessed. Two different reinforcement strategies based in impact modifiers, reactive or nonreactive, are investigated and their performances compared. Finally, the reprocessing potential of the produced blends is also identified. The contribution of the presence of impact modifiers on the different structural modifications observed previously can help to better understand their action and the different mechanisms taking place. Throughout this work, processing parameters and the rheological response of the blends are discussed. Thermal transitions and the morphology of the blends also guide their understanding. Finally, aspects such as the effect of the physical aging of the PET matrix are investigated. The main objective of this PhD work is, therefore, to expand the recycling possibilities of PET, facilitating it without affecting its ecological balance

APA, Harvard, Vancouver, ISO und andere Zitierweisen

36

Sritragool, Kunlapaporn. „Modification of Rubber Particle filled Thermoplastic with High Energy Electrons“. Doctoral thesis, Universitätsbibliothek Chemnitz, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-201000954.

Der volle Inhalt der Quelle

Annotation:

In present study, high energy electrons were used to modify blends based on RP and PP under two conditions: stationary and in-stationary conditions. Modification of blend under stationary condition is a process which is established in industrial application and where required absorbed dose is applied to form parts (after molding) at room temperature and in solid state. On the contrary, the modification of blend with high energy electrons under in-stationary condition is a new process (electron induced reactive processing) where required absorbed dose is applied to a molten state during melt mixing process. The modification of blend based on RP and PP under stationary condition resulted in slightly enhancement of tensile properties while the modification of this blend under in-stationary condition resulted in deterioration of tensile properties due to degradation of the PP matrix. Thus, special grafting agent (GA) is required for improving the tensile properties. The effect of different GAs on tensile, thermal, dynamic mechanical as well as morphological properties and melt flow properties of blends based on RP and PP were determined. The optimum absorbed dose for modification of blend based on RP and PP under both conditions was evaluated. In addition, the effect of treatment parameters of electron induced reactive processing was investigated.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

37

Krbalová, Maria. „Řízení kvality procesů zpracování biologicky rozložitelných odpadů“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230180.

Der volle Inhalt der Quelle

Annotation:

The waste production and especially biodegradable waste is following mankind since the beginning of his existence. This thesis deals with a description and dividing of current available waste process technologies, including description of their advantages and disadvantages. The work is also focused on the more detailed description of the composting technology, its control and opportunities to influence on resulting parameters of compost product. The information about technical description of workplace equipments, including industrial and technological processes was provided by the company VIA ALTA from their compost plant in Blansko.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

38

Öberg, Wictor. „STACKS“. Thesis, Konstfack, Keramik & Glas, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-7246.

Der volle Inhalt der Quelle

Annotation:

I’ve made my own currency, created my own wealth. This work is a metaphor for the acquisitiveness that rules and affect our time. I’m thinking about the capitalistic culture where wealth out- weighs everything else. I see it as denial of true values. Money is an illusion that we as a society have let dictate the worlds distribution of rights, as well as its responsibilities. I want to create the same illusion of value, and through that, possibly have created something valuable. The moment when the existing and non-existing blends together. I see it as my mission to bend our conceptions of materiality. I almost exclusively use recycled materials in my practice, because I can. The materials are there, and I see them. This figuration of stacks, made of different materials trough different techniques, might give all materials equal worth and cancel out the hierarchy of values.

Opponent vid examinering: Åsa Elzén

APA, Harvard, Vancouver, ISO und andere Zitierweisen

39

Ponsot, Inès. „Glasses and Glass-Ceramic Components from Inorganic Waste and Novel Processing“. Doctoral thesis, Università degli studi di Padova, 2015. http://hdl.handle.net/11577/3424636.

Der volle Inhalt der Quelle

Annotation:

Thanks to European environmental rules and regulations establishment, waste recycling has become a more and more relevant problematic. For manufacturing plants, especially those producing hazardous wastes, expenses linked to waste production have drastically increased over the last decades. In the proposed work, various hazardous and non-hazardous wastes, among: soda-lime and borosilicate glass cullet, cathode ray tubes glass, exhausted lime from fume abatement systems residues, sludge and slags from ferrous and non-ferrous metallurgy, and pre-stabilized municipal solid waste incinerators ashes are used to elaborate several compositions of glass-ceramics. High-temperature treatment (minimum 800 °C) associated to a Direct Sintering process (30 min) was an efficient way to stabilize chemically the final products. The impact of each waste on the final product’s mechanical properties was studied, but also their synergies between each other, when mixed together. Statistic mixture designs enabled to develop interesting products for modern building applications, such as porous tiles and lightweight panels destined to insulation, with a purpose of fulfilling multifunctional properties.
Grazie alle regole e normative ambientali europee istituite, il riciclaggio dei rifiuti è diventato una problematica sempre più rilevante. Per gli impianti di produzione, in particolare quelli che producono rifiuti pericolosi, le spese connesse allo smaltimento sono drasticamente aumentate negli ultimi decenni. Nel lavoro proposto, vari rifiuti, pericolosi o no, vengono utilizzati per elaborare diverse composizioni di vetroceramiche. Si distinguono rottami di vetro della produzione di finestre, di contenitori farmaceutici e di tubi catodici. I rifiuti non vetrosi invece sono calce esausta da residui di sistemi di filtrazione di fumi, scorie metallurgiche da leghe ferrose e non e ceneri da inceneritori. E' presentata nel presente lavoro la ricerca di un metodo di trattamento ad alta temperatura (minima 800 ° C) efficace per stabilizzare chimicamente il prodotto finale, tramite i diversi processi di sinterizzazione diretta, sinter-cristallizzazione e vetrificazione. Sono stati studiati gli effetti di ogni rifiuto sulle proprietà meccaniche del prodotto finale, ma anche le nuove funzionalità ottenute attraverso le sinergie risultanti dalla loro miscela. Miscele calibrate hanno permesso di sviluppare prodotti interessanti per applicazioni edilizie moderne, come le piastrelle porose e pannelli leggeri destinati all’isolamento.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

40

GABRIEL, LEANDRO. „Preparação, irradiação e caracterização de blendas PEAD reciclado/EPDM“. reponame:Repositório Institucional do IPEN, 2016. http://repositorio.ipen.br:8080/xmlui/handle/123456789/26946.

Der volle Inhalt der Quelle

Annotation:

Submitted by Marco Antonio Oliveira da Silva (maosilva@ipen.br) on 2016-12-22T16:34:05Z No. of bitstreams: 0
Made available in DSpace on 2016-12-22T16:34:05Z (GMT). No. of bitstreams: 0
A reciclagem de refugos é um processo estratégico que viabiliza a expansão do mercado de plásticos, podendo gerar novos produtos. A obtenção de blendas poliméricas é uma alternativa nesse processo, já que é conhecida a perda de propriedades mecânicas dos termoplásticos nas etapas de reprocessamento. Neste trabalho, o polietileno de alta densidade (PEAD) reciclado teve adições de borracha do monômero etileno-propileno-dieno (EPDM) puro em baixos teores (1 %, 5 % e 10 %), cujo objetivo foi formar blendas miscíveis e um produto final mais resistente ao impacto. O PEAD foi submetido a quatro ciclos de moagem, extrusão e injeção (reprocessamento) e misturado ao EPDM puro por extrusão sem o uso de qualquer aditivo. Os grânulos da blenda formada foram usados para confeccionar os corpos-de-prova por injeção para seu uso nas distintas metodologias analíticas. O processo de irradiação gama foi aplicado nas doses de 50 kGy e 100 kGy e os parâmetros físico-químicos e mecânicos dessas amostras foram comparados aos das não irradiadas. Tanto as blendas irradiadas como as não irradiadas mostraramse visualmente e microscopicamente homogêneas, indicando a compatibilidade da mistura, que também é verificada por seu comportamento térmico. Os parâmetros mecânicos provenientes dos ensaios de tração e flexão, foram semelhantes nas amostras do termoplástico virgem e do reciclado; o processo de irradiação nas blendas gerou sua reticulação, sendo esta verificada não só pelo aumento dos valores desses parâmetros como também pelo aumento da fração gel. A resistência ao impacto aumentou cerca de duas vezes e meia nas amostras com maior teor de EPDM e cerca de 6 a 7 vezes nestas mesmas amostras irradiadas a 50 kGy e 100 kGy respectivamente. O novo material obtido tem fortes indicativos para a sua utilização na pequena e média indústria de plástico, uma vez que já com 1 % de EPDM apresentam melhores características mecânicas em relação ao termoplástico reciclado quatro vezes e essas características foram incrementadas após o processo de irradiação gama.
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP

APA, Harvard, Vancouver, ISO und andere Zitierweisen

41

FONSECA, ANA C. M. „Processos de obtenção e caracterização físico-química de quitinas e quitosanas extraídas dos rejeitos da indústria pesqueira da região de Cananéia – SP“. reponame:Repositório Institucional do IPEN, 2016. http://repositorio.ipen.br:8080/xmlui/handle/123456789/26794.

Der volle Inhalt der Quelle

Annotation:

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-11-11T09:14:09Z No. of bitstreams: 0
Made available in DSpace on 2016-11-11T09:14:09Z (GMT). No. of bitstreams: 0
A quitina é o principal produto obtido do processamento das cascas de crustáceos. Esse biopolímero e o seu derivado, quitosana, têm despertado grande interesse comercial em virtude das possibilidades de aplicações que possuem. O gerenciamento desses resíduos e dos subprodutos gerados nas etapas no processo de obtenção pode ser considerado um modelo de biorrefinaria. A implementação de plantas para extração de quitina e quitosana é um desafio, uma vez que a demanda produtiva deve ser atendida sem causar danos ao meio ambiente. Uma grande variedade de quitosanas com diferentes propriedades físicoquímicas podem ser obtidas variando-se as condições de reação. Essas propriedades dependem da origem da matéria-prima, do seu grau médio de desacetilação, distribuição média dos grupos acetil ao longo da cadeia principal e da sua massa molecular média. Os fornecedores de quitosana comercial geralmente não mencionam a procedência da matéria-prima e pouca ou nenhuma informação é fornecida acerca do seu processamento. Sendo assim, as características e a reatividade do produto final podem variar gerando resultados não reprodutíveis. No presente estudo, foi utilizada a biomassa oriunda de rejeitos da indústria pesqueira de camarão da região de Cananéia SP. As amostras de - quitina foram obtidas por dois procedimentos diferentes: no primeiro, P1, as cascas de camarão após passar pelo pré-tratamento (lavagem, secagem e moagem) foram desproteinizadas para retirada das proteínas em hidróxido de sódio (NaOH) diluído nas concentrações 2%, 5% e 10% e desmineralizadas em ácido clorídrico (HCl) a 20% (v/v) para retirada dos carbonatos; no segundo procedimento, P2, essas etapas foram invertidas. A biomassa resultante foi desacetilada com hidróxido de sódio concentrado a 30%, 40% e 50% em tempos que variaram de 2 a 6 horas. As principais propriedades físico-químicas das amostras de quitosanas obtidas foram determinadas utilizando a espectroscopia na região do infravermelho com transformada de Fourier (FT-IR) para a determinação do grau médio de acetilação, GA, e a técnica de titulação ácido-base mensurada por condutimetria foi utilizada para comparar os resultados; a viscosimetria capilar para a determinação da massa molar média viscosimétrica, Mv , e a difração de raios X (DRX) para avaliar o grau médio de cristalinidade, X. Além disso, foram empregadas as técnicas de microscopia eletrônica de varredura (MEV) para análises morfológicas dos materiais obtidos e a espectrometria de fluorescência de raios X por dispersão de comprimento de onda (WDXRF) para análise química das quitosanas. O GA e o X das amostras diminuíram à medida em que o tratamento se tornou mais vigoroso, enquanto a Mv aumentou. O procedimento 2 foi o mais viável por eliminar a etapa de despigmentação, pois originou amostras com tonalidade mais clara e fáceis de pulverizar.
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

APA, Harvard, Vancouver, ISO und andere Zitierweisen

42

Gellner, Martha. „Mechanische Aufbereitung der Feinfraktion zerkleinerter Lithium-Ionen-Batterien“. Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2018. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-235403.

Der volle Inhalt der Quelle

Annotation:

Bei einem entwickelten Verfahren zur mechanischen Aufbereitung von Lithium-Ionen-Batterien (LIBs) aus Elektrofahrzeugen fallen zwei, hauptsächlich aus den Elektrodenbestandteilen bestehenden, Feinfraktionen (FF) an. Typischerweise erfolgt eine Rückgewinnung der enthaltenen Wertstoffe Co, Ni und Cu derzeit über eine kombinierte pyro- und hydrometallurgische Aufbereitung. Dabei dient der pyrometallurgische Schritt der Abtrennung von Stoffen, welche bei der hydrometallurgischen Aufbereitung störend wirken. Durch eine mechanische Aufbereitung der FF wurde alternativ zu dem pyrometallurgischen Schritt versucht, die in der FF enthaltenen Wertstoffe anzureichern sowie ebenfalls die Störstoffe für eine hydrometallurgische Aufbereitung abzutrennen. Dazu wurden verschiedene trockene Sortierprozesse herangezogen und auf ihre Eignung hin untersucht. Mit Hilfe der Ergebnisse wurde ein Verfahrensfließbild für die Aufbereitung der FF entworfen und testweise durchlaufen. Zusätzlich zu den Sortierversuchen wurden eine Materialcharakterisierung durchgeführt, die Aufschlussverhältnisse (visuelle Einschätzung, Bestimmung Aufschlussgrad) sowie die Aufschlusszerkleinerung der FF untersucht. Als Aufgabegut diente eine Co-, Ni-, Mn- haltige FF, welche nach der 1. Zerkleinerung und Klassierung im entworfenen Verfahrensfließbild zur Aufbereitung der LIBs aus Elektrofahrzeugen gewonnen wurde. Zur Anreicherung der Wertstoffe Co, Ni innerhalb des Aktivmaterials (AM) und Cu sowie zur Reduzierung der Störstoffgehalte von Al und Kohlenstoff in bestimmten Produkten haben sich die Siebklassierung, die Magnetscheidung, die Gegenstromsortierung sowie als nasser Dichtesortierprozess die Schwimm-Sink-Sortierung als geeignet herausgestellt. Als resultierendes technologisches Aufbereitungsverfahren haben sich aus den Ergebnissen eine Siebklassierung bei x = 200 µm und x = 800 µm mit einer nachgeschalteten Magnetscheidung oder Gegenstromsortierung für die Klasse 0,2…0,8 mm ergeben, woraus 4 Produkte resultieren. Beim testweisen Durchlaufen des resultierenden Verfahrensfließbildes hat sich zudem herausgestellt, dass in Abhängigkeit von der FF bzw. deren Kenngrößen auf die Magnetscheidung bzw. Gegenstromsortierung verzichtet werden kann. Insgesamt wird zur Aufwands- und Kostenminimierung eine Vereinheitlichung der aufzubereitenden FF empfohlen. Die Wirtschaftlichkeit des Verfahrens (inklusive Pyro- und Hydrometallurgie) wird stark durch die dynamische Entwicklung der Batterietechnologie, insbesondere der enthaltenen erlösbringenden Komponente Kobalt, und des Marktes (Verkaufsraten und Lebensdauer der LIBs) beeinflusst. Die notwendige kontinuierliche Anpassung des bestehenden Verfahrensfließbildes aufgrund der schnellen Weiterentwicklung chemischer LIB-Regime ist zudem nicht vermeidbar. Generelle Unterschiede in den FF (chemische Zusammensetzung, PGV) können auf verschiedene LIB-Typen (unterschiedliche AMs), deren Vorgeschichte (Alterungszustand, Lagerung, …) sowie die Zerkleinerungsbedingungen zurückgeführt werden. Mit Hilfe einer Bilanzierung wurden die Gehalte des gesamten AM in den FF zwischen c = 33,2 ± 3,4 Ma.-% und c = 54,9 ± 5,7 Ma.-% ermittelt. Mit Hilfe der untersuchten Methoden wurde in keinem Produkt der maximale Anreicherungsfaktor für die AMs erreicht, so dass lediglich eine Voranreicherung bezüglich dieser (und auch der anderen Komponenten) erzielt wurde. Betrachtungen zu den Verbindungs- und Aufschlussverhältnissen in der FF führten zu dem Ergebnis, dass sowohl die Anodenbeschichtung noch mit der Kupferfolie als auch die Kathodenbeschichtung mit der Aluminiumfolie im Verbund vorliegen können. Bezüglich der AMs wird ein Aufschluss im Partikelgrößenbereich größer der Primär- und Sekundärpartikelgröße (> 1 bis 20 µm) ausgeschlossen. Es konnte ein maximaler Aufschlussgrad von A = 37,9 % für eine der untersuchten Feinfraktionen bestimmt werden. Zur Zerkleinerung der Partikel in der Feinfraktion eignen sich eine Zerkleinerung in der einer Fliehkraftmühle bzw. mittels Ultraschallbeanspruchung.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

43

Louizi, Molka. „Formulation de mélanges de polyoléfines à l’aide d’une extrudeuse à très haute vitesse : Application à la dispersion de particules de traceurs, détectables par fluorescence X ou UV, en vue du tri de déchets polymères post-consommation“. Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0134.

Der volle Inhalt der Quelle

Annotation:

Cette thèse, qui s’inscrit dans le cadre du projet ANR Eco-Tech TRIPTIC, a eu comme objectif de contribuer au tri industriel en cadence de polymères contenant des traceurs détectables grâce à leurs propriétés en fluorescence X ou UV. Dans un premier temps, étant donné que le coût des traceurs choisis pour l’étude TRIPTIC est assez élevé, nous avons réalisé une étude préliminaire, avec des particules modèles de silice, visant à optimiser la dispersion de charges dans une matrice polypropylène/éthylène propylène rubber (PP/EPR). Nous avons montré que l’extrusion à taux de cisaillement élevé est une technologie efficace permettant une dispersion homogène de charges de tailles micro ou nanométriques. Dans un deuxième temps, après optimisation des conditions de dispersion, nous avons extrapolé nos résultats à la dispersion de particules de traceurs UV dans différentes matrices thermoplastiques. Nous avons montré que la dispersion de 1000 ppm de particules de traceurs, de tailles micrométriques, dans des matrices polypropylènes, en extrusion à haute vitesse (N= 800 rpm), n’a pas d’impact sur les propriétés mécaniques et physico-chimiques des mélanges tracés, ainsi que sur la photo-dégradation sous rayonnement UV. Cette fine dispersion a non seulement permis la conservation des propriétés des polymères tracés mais aussi une bonne détection dynamique, tant en fluorescence X qu’UV, sur un prototype conçu par des partenaires du projet (Pellenc Selective Technologies, CEA-LITT et ENSAM- LCPI). Enfin, nous avons validé l’extrusion à haute vitesse pour compatibiliser des mélanges de polymères ternaires (PP/EPR)/PE (polyéthylène) pouvant correspondre à la valorisation de polymères post-consommation, par exemple dans l’hypothèse où on souhaite recycler (PP/EPR) et PE ensembles. Les propriétés prometteuses des mélanges obtenus doivent leur permettre de trouver des applications dans l’industrie automobile, par exemple. Cette voie est d’un grand intérêt pour les applications industrielles, car elle permet d’envisager des propriétés mécaniques élevées pour les polymères recyclés. Elle ouvre aussi de nouvelles perspectives pour l’élaboration de matériaux allégés, obtenus à partir de matières vierges ou recyclées
This thesis, which is part of the ANR Eco-Tech TRIPTIC project, had the objective of contributing to industrial sorting rate of polymers containing tracers detectable by their fluorescence X or UV properties. At first, given that the cost of tracers selected for TRIPTIC study is quite high, a preliminary study is conducted with models of silica particles to optimize the dispersion of fillers in polypropylene / ethylene-propylene rubber (PP / EPR) matrix. It was found that processing under high shear rate is an effective technology for accomplishing a homogeneous dispersion of micro or nanoscale fillers. In a second step, after optimization of dispersion conditions, our results are extrapolated to the dispersion of UV tracer in different thermoplastic matrices. It was shown that the dispersion of 1000 ppm of micrometer tracer particles, in polypropylene matrices, extruded at high shear rates (N = 800 rpm), has no impact on the mechanical and physico-chemical properties as well as in the photo-degradation of the polymer after UV irradiation exposure. This fine dispersion was beneficial not only for the conservation of the properties of traced polymers but also for achieving a good dynamic detection of UV or X tracers using a prototype developed by the project partners ( Pellenc Selective Technologies , CEA- LITT and ENSAM - RPI ). Finally, high shear processing has successfully used to the compatibilization of ternary blends ( PP / EPR ) / PE (polyethylene) which may correspond to the post-consumer polymers. This technique has proved to be an effective method to produce polymer blends with unique mechanical properties. This novel strategy of compatibilization is of a particular interest, especially for industrial application prospects. It also opens new perspectives for materials lightening as well as “high shear recycling” of immiscible polymers

APA, Harvard, Vancouver, ISO und andere Zitierweisen

44

Henriksson, Patrick. „Comparative Life Cycle Assessment of Sludge Treatment Systems : Is recycling aluminium based coagulant from chemical sludge the way of the future?“ Thesis, KTH, Strategiska hållbarhetsstudier, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-217097.

Der volle Inhalt der Quelle

Annotation:

Chemical coagulation is a widely used wastewater treatment method around the world to reduce impurities from the process water in various industries. However, the large amounts of coagulation chemicals that are required for the removal of dissolved particles create a chemical sludge which poses a great environmental problem. Purac AB, a Swedish wastewater treatment company attempts to solve this problem with a new technology called the ReAl process. The ReAl process can recycle the aluminium ions from the commonly used coagulant aluminium sulfate, which reduces the amount of chemical sludge and the amount of aluminium sulfate needed in the coagulation process. In this study, a comparative life cycle assessment was conducted with a cradle-to-grave approach and mostly in accordance with the ISO-14040 series with the only deviation of not including resource-based impact categories. The goal was to evaluate the environmental impact of two sludge treatment systems – a conventional system (system 1) and a system which includes the ReAl process (system 2). Furthermore, the environmental performance of two dewatering equipment’s, a decanter centrifuge and a filter press, were examined in system 1, while in system 2, the exclusion of sludge drying was investigated. The scope of the study did not include the infrastructure of the sludge treatment systems and the ReAl process since previous studies have shown that, the environmental impact from the infrastructure in the wastewater treatment industry is relatively small compared to other factors, such as the energy and coagulation chemical used in these systems. The characterization results showed that system 2 had the lowest environmental impact on all the evaluated impact categories. The results also revealed that system 1 would have a slightly lower environmental impact if the chemical sludge was dewatered with a decanter centrifuge instead of a filter press. Similarly, system 2 would have a slightly lower environmental impact if sludge drying was excluded from the system. However, the environmental performance gain from selecting the best dewatering and drying equipment is limited and considered within the margin of error. Thus, this thesis suggests selecting the sludge treatment equipment based on their economic and technical factors before their environmental performance. The largest environmental impact in system 1 derived from the use of the coagulation chemical aluminium sulfate, while in system 2, sulfuric acid used in the ReAl process contributed the most to its environmental impact. The sensitivity analysis showed that a “clean” electricity mix is essential for system 2 and the ReAl process overall impact on the environment compared to system 1.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

45

Dai, Zhao-Min, und 戴昭民. „Recycling Processing research for Multiple Solid Wastes“. Thesis, 2017. http://ndltd.ncl.edu.tw/handle/mmujre.

Der volle Inhalt der Quelle

Annotation:

碩士
遠東科技大學
機械工程研究所
105
If the waste in Taiwan can be recycled, the estimate market value is over 85 billion dollars. According to the statistics of Department of Waste Management, Environmental Protection Administration and Council of Agriculture in 2015, the multiple solid wastes disposed per year is 1,700,000 tons, and 800,000 tons of organic sludge, 100,000 tons of waste edible oil, 70,000 tons of expired food, 680,000 tons of waste from agriculture, forestry and animal husbandry and 80,000 tons of specific industrial waste. However, there are serious issues of low recycling rate, high cost, odor and environmental pollution, waste handling operators find it unprofitable after charging NT5,000 cleaning fee per ton due to no technology breakthrough, resulting in illegal affairs. In this study, organic wastewater treatment is confirmed that KOH and starch used as additives can replace traditional wastewater treatment with NaOH, PAC and Polymer. The result is affirmed by paper plant that they implement 1-ton scale wastewater treatment for recycling paper and the aluminum content is less than 1000ppm to solve the ecological problem of earthworm. The high calorific value RDF-5 in the study needs to be formed and changed according to mixing different sludge and waste. The dehydration drying time takes nearly 30 minutes and the initial high calorific value RDF-5 reaches 4,368kcal/kg, which is a lot higher than calorific value of dry organic sludge at 1,800kcal/kg and dry pulp sludge at 2,200kcal/kg. The research studies the method to use specific industrial waste as additives to increase calorific value of RDF-5, and the result reaches 6,796kcal/kg. There are still many ways to improve the calorific value of RDF-5 that deserves analysis. In this research, 19 ways of earthworm farming through organic sludge were conducted; in one month, the weight of breeding earthworm increased up to 1.2 times, and the aluminum content found in the earthworm fecal was less than 1000ppm. Further breeding does not cause any death of earthworms. The environmental control system of the research with multiple organic waste stimulates small-scale of earthworm farming reaches 1.44 yield. Finally, rapid composite of multiple waste disposal with 24-hour compositing to ripen the materials and feed earthworms and digest, the waste no longer heat after compositing and pH value can be controlled between 6 and 7, enabling earthworms to quickly adapted to multiple waste compost and multiply descendants. Through the high-value ecological treatment and high calorific value derivative energy resources of this research brings added value to the core technology and scientific service of circular economy, to further create green energy and sustainable environment.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

46

Lu, Yu-chang, und 呂育菁. „The safe culture assessment of metal recycling processing industy“. Thesis, 2011. http://ndltd.ncl.edu.tw/handle/50796547097851646707.

Der volle Inhalt der Quelle

Annotation:

碩士
國立高雄第一科技大學
環境與安全衛生工程研究所
99
Due to very limited establishment of a safety culture in the waste disposal industry of Taiwan, this study is conducted on the recycling/disposal trade of waste mobile vehicles, electrical home appliances and precious metals, in order to explore the health and safety compliance levels of rank-and–file workers of local metal recycling/disposal plants. By reviewing the earlier research papers, the study developed a safety culture rating scale covering eight dimensions for a total of 40 questions as the research instrument. The valid questionnaires received totaled 197, and were analyzed with SPSS 18.0 and LISREL statistical software. The study targets covered seven firms out of three industries, in which the lower-case letters a to g were used to name the seven firms, and capitals A to C were used to represent the three industries, respectively. After testing, a radar chart was used to show the percentage of the safety culture. Out of the 7 firms, only Company c’s safety culture fell below 80 points; the remaining 6 firms all obtained more than 80 points. In terms of industry’s safety culture, Industry A had the highest percentage, followed by Industry C; Industry B ranked the lowest. In terms of job posts, the safety culture levels in descending order were: section chiefs (including superiors) and above, others, industrial safety personnel, forepersons, on-site technical personnel, and engineers. This shows that those from different firms and industries, as well as from different posts have different levels of cognition of safety culture. By further applying ANOVA and post-hoc test, the variance in the safety culture dimensions of personnel in varying posts, industries and companies can be better understood. Finally, the study adopted factor analysis of structural equation modeling to confirm if the questions set in accordance with the eight safety culture dimension are congruent with the common factor (potential conception). The confirmatory analysis confirmed that the questionnaire designed by the study is appropriate for implementation on local metal recycling/disposal plants.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

47

Jhang, Ruei-Yong, und 張睿詠. „The Sterilization of Recycling D.I.Water in TFT LCD Processing“. Thesis, 2019. http://ndltd.ncl.edu.tw/handle/yxw385.

Der volle Inhalt der Quelle

Annotation:

碩士
國立高雄大學
電機工程學系碩博士班
107
In both the wet etching and PR stripping of TFT LCD fabrication, large amount of DI water is necessary to clean chemicals residuals after wet etching and PR stripping in order to avoid over-etching of the circuit pattern and PR residue. However, hyphae containing in the recycling DI water can result in defects of the circuits, so the recycling DI water has to be regenerated after a period of time. When the contaminated area of the hyphae gets large, there will be existence of abnormalities, such as cracks in the PVD/CVD coatings that can result in rework or disqualification. Moreover, the formation rate of hyphae is degraded more rapidly in PR stripping than in wet etching. This thesis is focused on the study of the mechanisms of hyphae formation in the PR stripping process and to develop an effective process for recycling DI water to inhibit the deterioration in TFT LCD processes.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

48

Blackstock, Ross. „Pre-treatment processing of household plastic packaging waste“. Thesis, 2016. http://hdl.handle.net/10539/22329.

Der volle Inhalt der Quelle

Annotation:

A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, in fulfilment of the requirements for the degree of Masters in Engineering. Johannesburg, 2016
The purpose of this investigation was to investigate whether or not it would be possible to separate blow moulded and injection moulded waste plastics using two techniques; air classification and ballistic separation. Air classification and ballistic separation are two techniques that separate different types of material according to size, shape and density. Previous research, together with new measurements, has suggested that blow mould plastics tend to be thinner in terms of wall thickness than injection moulded plastics meaning that air classification could be used to separate each type of plastic. The material used for the study was supplied by a Romanian recycler and was a mixture of High Density Polyethylene and polypropylene. Two additional samples, one Polyethylene rich and the other polypropylene rich, were also included in the research. The first part of the study involved measuring different characteristics of the material to determine how to go about performing the different air classification experiments. The second part of the study focused on separating the different material samples using different air classifier systems and a ballistic separation system. The third part of the study focused on processing the samples from part 2 (air classification) into test specimens for further mechanical and melt flow property measurements. After measuring the mechanical and melt flow properties of the different samples it was found that air classification did not substantially improve the mechanical or melt flow properties of the material. The study did, however, show that there is a strong correlation between polymer type and melt flow properties. High Density polypropylene is generally used for blow mould applications whereas polypropylene is generally used for injection mould applications. Separating the material according to polymer type therefore means that the material is, to an extent, also sorted according to melt flow properties.
MT2017

APA, Harvard, Vancouver, ISO und andere Zitierweisen

49

Wu, Weizhen, und 吳瑋真. „The Performance on Foam Extinguishment and Ventilation Improvement in Recycling Processing Plant“. Thesis, 2012. http://ndltd.ncl.edu.tw/handle/6p7bcy.

Der volle Inhalt der Quelle

Annotation:

碩士
長榮大學
職業安全與衛生學系碩士班
100
The sources of the waste recycled by recycling processing plants are schools, laboratories of research affiliates, and pilot plants; the characteristics of the waste is little in amount, diverse in variety, toxic, combustible, corrosive etc. Most of the materials are hybrid mixtures, which easily produce liquid and solid wastes, which causes harmful gases and particles to be released into the air; not only does it pose a threat to the health of the workers inside the factory, but after conducting inspections, it also endangers the work place because of the low flash point of hybrid mixtures. Therefore, it is hoped that this experiment can be used to test the reliability of using foam-based fire extinguishing equipment on these wastes, and also to evaluate the ventilation of the recycling processing plant, with the hope of ensuring the safety and health of the personnel. This research underwent performance tests by using the different release pressures of 2.5kgf/cm2, 3.5kgf/cm2, and 5kgf/cm2on the brand X foam used previously by the recycling processing plants and the brand A foam used now, while using industrial alcohol and gasoline as the fuel. Results showed that the previously used brand X foam performed poorly, sometimes not even being able to extinguish the fires. From the results given by the experiment using the currently used brand A foam, it was found that it could most effectively extinguish the fires when the release pressure was set at 3.5kgf/cm2. Therefore, when this research used that release pressure to extinguish the fires created by waste A, waste B, or a mixture of A+B, the fires could all be extinguish within one minute. This research used Fire Dynamics Simulator (FDS) to simulate the ventilation within the factory. Initial simulations indicated that the work area was adequately ventilated, but the places where personnel rarely entered, such as above the dosing motor area and behind the storage tank, were dead ends for the ventilation, which would pose threats to the health of personnel entering the area. Therefore, this research is aimed at discussing and modifying the areas with poor ventilation. From the simulations, it was discovered that the addition of vents near the dozing motor area would improve the ventilation of the area. This research also increased the amount of air suction from the ceiling of the work place along with the addition of vents in order to evaluate if the amount of air suction was adequate or not; results showed that this procedure could decrease the amount of time needed for the pollutants to be ventilated while also significantly improving the ventilation of the work place as a whole.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

50

CHANG, CHIA-HSIEN, und 張家嫻. „The study of processing / recycling hazardous industrial waste -On the case of A company“. Thesis, 2012. http://ndltd.ncl.edu.tw/handle/49976209460130115194.

Der volle Inhalt der Quelle

Annotation:

碩士
國立中央大學
產業經濟研究所在職專班
101
We human beings pay more and more attention on environment protection and resource reuse recent years. For business development and ecological protection, Taiwan government not only established environment protection areas in Taoyuan, Tainan, Kaohsiung and Hualien, but also support the related business such as resource recycling, renewable energy…etc. This study discusses the about electric arc furnace steelmaking dust, one of hazardous industrial waste, riches in divalent metals such as zinc, iron, lead and chromium. Thus, lots of nations devote to the related research and develop their technique of electric arc furnace steelmaking dust recycling. It decreases the influence on the environment of those hazardous materials, and such limited resources can be reuse. To investigate the relationship between the recycling of harmful industrial waste and emissions of pollutants, the research materials used in this article is from A Company’s financial statement, production report, and pollution emissions data. By using the KLEM I-O model, regression analysis and industrial competition analysis, our results show: (1) There is a significant positive relationship between products and electricity costs and investment in the raw flue dust, (2) Pollutant emissions have significant positive relationship with the amount of hazardous waste treatment and material use.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Dissertationen zum Thema „Recycling processing“

Geben Sie eine Quelle nach APA, MLA, Chicago, Harvard und anderen Zitierweisen an