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Biodegradation Experiments of Polymeric Materials: Monitoring and Analysis / Bionedbrytning av Polymera Material: Undersökning och AnalysOjala, Sini January 2021 (has links)
Plastskräp har blivit ett global problem på grund av nedskräpning och otillräcklig avfallshantering. Användning av biologiskt nedbrytbart material kan underlätta problemet, även om det inte är en universallösning. Produkter gjorda av biologiskt nedbrytbart material skall ändå till avfallshantering eftersom nedbrytningen kan vara långvarig och variera mycket beroende av omgivningen. Därmed är användningen av biologiskt nedbrytbart material endast berättigat då det är svårt att samla in materialet eller avskilja det från organiskt material. Studiens mål var att undersöka biologiskt nedbrytbara material som kan användas i produkter som fungerar under många olika driftsförhållanden och inte kan återställas efter användning. I den litterära delen av denna studie definieras nedbrytning genom egenskaper och förhållanden som påverkar nedbrytningsprocessen. Nedbrytning av polyestrar och cellulosa och de standardprocessarna som används i nedbrytningsexperimenten betraktades. Standardprocesserna för nedbrytning studerades för att få en klarare inblick i den eftertraktade nedbrytningsgraden och de standardiserade förhållandena för nedbrytningen i olika miljöer. En sammanfattning av olika nedbrytningsexperiment och analysmetoder är också inkluderade för att försäkra att experimenten som utfördes är både giltiga och jämförbara med andra forskningsresultat inom fältet. I detta forskningsprojekt utfördes nedbrytningsexperiment i färskvatten- och hemkompostmiljöer. Målet med projektet var att bedöma ifall materialen kunde brytas ned i ett brett spektrum av miljöer, ifall de var mindre skadliga för naturen än konventionella material som används av dagens industri och för att uppskatta nedbrytningstakten. Nedbrytningstiden var 140 dagar och experimentet utfördes med 10 olika material: betecknade som A-J. Materialen analyserades 8 gånger under nedbrytningsperioden förutom materialen I och J som analyserades en gång efter 140 dagar. Materialen analyserades mekaniskt, strukturellt och termiskt med hjälp av dragprovning, FTIR och DSC. Provernas viktförändring bestämdes också. Nedbrytning observerades visuellt från provernas yta och genom mekaniska prover. Materialen som placerades i hemkomposten visade klara tecken på nedbrytning då färgen hade förändrats och förstärkningsfibrerna hade blivit synliga. Materialen som placerats i hemkompostmiljö visade också klara tecken på tillväxt av mikroorganismer och biomassa som uppstått på ytan av materialen. Sammanfattningsvist, visade materialen B, C och G de mest lovande resultaten med klara tecken på biologisk nedbrytning och de hade en snabbare nedbrytningstakt än de andra materialen som undersöktes. Material D visade klara tecken på biologisk nedbrytning på ytan men dess nedbrytningstakt var uppskattad att vara mycket långsammare. Därmed rekommenderas det att använda material A, B, D och G istället för konventionella icke biologiskt nedbrytbara material. Dessa material har potential att sänka den negativa inverkan och de långsiktiga riskerna av plastskräp för miljön. / Plastic debris has become a global crisis due to littering and misplaced waste management. The use of biodegradable materials can ease the problem, but it is not always the answer. Products made of biodegradable materials are still to be waste managed since biodegradation can be a long process and is highly dependent on the environment conditions. Hence, the use of biodegradable materials is justified only when retrieving the product after use is impossible or prohibitively expensive or separating it from organic matter is difficult. This study was made to investigate biodegradable materials that can be used in products that are operating in broad range of operational conditions and cannot be retrieved back after use in most cases. In the literature part of this study the biodegradation is defined along with properties and conditions that affect the biodegradation process. Biodegradation of polyesters and cellulose, and standards used in the biodegradation experiments were reviewed. Biodegradation standards were studied in order to have a clearer picture of the pursued degree of biodegradation and standardized properties in the biodegradation experiments. Review of different biodegradation tests and analysis methods are included as well to ensure that the experiments performed in this work are valid and comparable with other biodegradation studies. In this study, the biodegradation experiment was conducted in freshwater and home compost environments. The aim was to determine if the materials were able to biodegrade in wide range of environments, to make sure they are less harmful than the conventional materials used in the industry and to estimate the rate of biodegradation. The duration of the experiments were 140 days with 10 different materials: A – J. The materials were analyzed 8 times during the aging period, except materials I and J, which were analyzed only once after 140 days. The samples were analyzed mechanically, structurally, and thermally using tensile test, FTIR and DSC measurements, respectively. Also, the samples weight changes were analyzed. The degradation was visually observed from the surfaces of the samples and from mechanical testing in both experimental environments. Home compost environment showed clear signs of biodegradation where reinforcement fibers became visible and changed the color of some of the samples. Also, home compost samples had microorganisms growing on them, and biomass was developing around them. To conclude, material B, C and G had the most promising results with clear signs of biodegradation and had faster estimated biodegradation rate compared with the other studied materials. Material D had signs of biodegradation on the surface as well. However, the biodegradation rate was estimated to be much slower. In conclusion, it is recommended to use the studied materials A, B, D and G instead of the conventional non-biodegradable polymers. These materials have potential to lower the negative impact and long-term risks of plastic debris to the environment.
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Dinâmica da matéria orgânica em solo tratado com resíduos orgânicos nos Tabuleiros Costeiros do Estado de Sergipe / Organic matter dynamics in soil treated with organic waste in the Coastal Plains of the state of SergipeMoura, Juliana Augusta 15 October 2013 (has links)
In the state of Sergipe, more precisely in the center-south region of the Coastal Plains
serves as the stage for one of the largest citrus production in the country. The intensive
cultivation of these soils reduces the content of organic matter that is the key component to
ensure its quality. Thus, the use of alternate layering residues format, can be a viable
alternative to the revitalization of citrus orchards. The objective of this study was the
evaluation of the labile and stable soil organic matter, carbon management index and
microbial activity in soil treated with organic waste and citrus cultivation in the state of
Sergipe. Soil samples were collected in the layers 0-5 cm, 5-10 cm, and 10-15 cm in a
citrus (Citrus sinensis, L. Osbeck) orchard treated either with organic residues or mineral
fertilizer, or a combination of the two (conventional management, where the projection of
the plant canopy was kept clean of weeds, and no mineral fertilization; humus residues;
alternate layering residues (in situ made compost); alternate layering residues + NPK; only
NPK; humus residues + NPK; and a native forest soil as reference). The results were
submitted to analysis of variance and means were compared by the Scott-Knott test at 5%
probability by the software SISVAR. To evaluate the microbial activity was also
determined the coefficient of correlation (p . 5) via the computer application SAEG. The
study of C in the labile and stable organic matter were more effective than isolated
evaluation of total organic carbon (TOC) to check for changes in the dynamics of C in the
soil. The C in particulate organic matter (C-POM) was more sensitive than the content of C
in complexed organic matter (C-COM). Overall, the treatments that have provided
incorporation of organic residues showed carbon management index (CMI) close to the
native forest. The fulvic acids fraction (FAF) helped identify the changes in soil for
different types of management. The humin fraction (HUMF) showed the highest levels of
C relative to FAF and humic acids fraction (HAF). The incorporation of organic waste to
the crowning of the orange zone also caused an increase in microbial respiration rates, in
total content of organic matter, as well as the elevation of pH, P, Ca and Mg treatments
when compared to native forest and conventional management. The ratio stratification was
effective to evaluate the influence of different management practices between depths
indicating treatments Humus, Humus + NPK and altenate layering residues + NPK as the
most effective in increasing the organic matter content in the soil. The benefits caused to
soil after the incorporation of organic waste show that the use of practices more
conservationist contributes to the improvement of the soil. / No estado de Sergipe, mais precisamente no centro-sul, a regiao de Tabuleiros Costeiros
serve de palco para uma das maiores producoes citricolas do pais. O cultivo intensivo feito
de forma inadequada nesses solos reduz o teor de materia organica que e o componente
fundamental para assegurar a sua qualidade. Dessa forma, o aproveitamento dos residuos
organicos no formato de compostagem laminar, pode ser uma alternativa viavel para a
revitalizacao de pomares citricolas. O objetivo do presente trabalho foi a avaliacao das
fracoes labeis e estaveis da materia organica do solo, do indice de manejo do carbono e da
atividade microbiana em solo tratado com residuos organicos e cultivado com citros no
estado de Sergipe. Foram coletadas amostras de solo em tres profundidades (0-5, 5-10 e
10-15 cm) em area cultivada com laranja pera (Citrus sinensis, L. Osbeck) sob diferentes
tratamentos (manejo convencional onde a area sob a copa da planta e mantida limpa e sem
aplicacao de fertilizantes; humus, aplicado sob a copa da planta; compostagem laminar,
com residuos organicos como restos culturais e estercos dispostos em camadas alternadas
sob a copa da planta; compostagem laminar + NPK; NPK; humus + NPK; o mesmo solo
sob mata nativa foi usado como referencia). Os resultados foram submetidos a analise de
variancia e as medias foram comparadas pelo teste de Scott-Knott a 5% de probabilidade
por meio do software SISVAR. Para avaliacao da atividade microbiana tambem foi
determinado o coeficiente de correlacao de Pearson (p.5) atraves do aplicativo
computacional SAEG. O estudo do C nas fracoes labeis e estaveis da materia organica
foram mais eficazes do que avaliacao isolada do carbono organico total (COT) para
verificar alteracoes na dinamica do C no solo. O C da materia organica particulada (CMOP)
se mostrou mais sensivel do que o teor de C na materia organica complexada (CMOC).
No geral, os tratamentos que tiveram incorporacao de residuos organicos
proporcionaram indices de manejo de carbono (IMC) proximos ao da mata nativa. A fracao
acidos fulvicos (FAF) ajudou a identificar as mudancas ocorridas no solo em funcao dos
diferentes tipos de manejo. A fracao humina (FHUM) apresentou os maiores teores de C
em relacao a FAF e a fracao acidos humicos (FAH). A incorporacao de residuos organicos
a zona de coroamento da laranjeira tambem promoveu um aumento das taxas de respiracao
microbiana, nos teores totais de materia organica, assim como, a elevacao de pH, P, Ca e
Mg dos tratamentos quando comparados a mata nativa e ao manejo convencional. A
relacao de estratificacao mostrou-se eficaz ao avaliar a influencia das diferentes praticas de
manejo entre as profundidades indicando os tratamentos Humus, Humus + NPK e
compostagem laminar + NPK como os mais eficazes em aumentar o teor de materia
organica no solo. Os beneficios ocasionados ao solo, apos a incorporacao de residuos
organicos demonstram que a utilizacao de praticas mais conservacionistas contribui em
muito para a melhoria do solo.
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Suivi physico-chimique, microbiologique et écotoxicologique du compostage de boues de STEP mélangées à des déchets de palmier : validation de nouveaux indices de maturité / physico-chemical microbiological and ecotoxicological monitoring during composting of sewage sludge-date palme waste : validation of new maturity indexEl Fels, Loubna 20 December 2014 (has links)
Le traitement de boues de station d'épuration (Boues activées de Marrakech) en mélange avec déchets verts (Palmier dattier) selon deux mélanges dont les proportions : A (1/3 Boues + 2/3 Déchets de palmier) et B (1/2 Boues + 1/2 Déchets de palmier), a été effectué par la filière du compostage, pendant six mois. Au cours du co-compostage, l’intense activité microbienne s’est traduite par une augmentation de température (autour 65 C°) au cours des premières semaines (phase thermophile) et un taux de décomposition final de l’ordre de 40%. Après six mois de co-compostage, le compost final est caractérisé par un rapport C/N voisin de 10, un rapport de NH4+/NO3- < 1, un pH autour de la neutralité signe de maturité des composts. L’analyse FTIR a montré une diminution de l'absorbance des bandes aliphatiques et l'augmentation de la structure de bandes d'absorbance aromatiques reflètent l'état d'avancement du processus d'humification. Le taux d’abattement des lipides totaux est de l’ordre de 43%. Les esters méthyliques d’acide gras (FAMEs) des Gram-positif (i,C15 :0) ont augmenté durant la phase thermophile. Les FAMEs d’origine non spécifique (C6 :0, C14 :0) ont connu une intense diminution, les FAMEs de bactéries non spécifiques représentent une grande teneur durant la phase thermophile. L’indice CPI a augmenté à la fin du co-compostage indiquant l’enrichissement du compost en FAMEs d’origine végétale. Les principaux composés ligneux identifiés, au cours du co-compostage, par Py-GC-MS, sont classés en deux groupes. Le premier est constitué de 7 composés dont la teneur diminue au cours du co-compostage, parmi lesquels : Toluène, 2,4-diméthylbenzène, éthylbenzène, Styrène, 1-éthyl-2-méthylbenzène, 4-méthylphénol et 2-méthylnaphthalène. Le deuxième groupe est constitué de 4 composés qui augmentent au cours du co-compostage : phénol, benzofuran, éthylméthoxyphénol et diméthoxyphénol. Les principaux stéroïdes identifiés sont les C27-C29 sterènes, stanols, 5β-cholesta-3-one, cholesta-3,5-diène et 2 thiostéranes. A l’exception des thiosteranes et quelques composés de C27-C29 cholestenes la concentration relative des stéroides diminue au cours du processus suit à leur attaque microbien. L’abattement total de la teneur des stéroïdes est corrélé positivement avec les indicateurs de maturité du compost (C/N et NH4+/NO3-) ce qui ouvre la voie à une éventuelle utilisation des stéroïdes comme indicateur de dépollution et de maturité de compost. 12 isolats d’actinomycètes ayant une activité antimicrobienne vis-à-vis d’un large spectre des germes pathogènes ont été isolés sur le milieu sélectif CTEA. Le degré d’hygiénisation est confirmé par la diminution de la concentration des coliformes fécaux et totaux, et l’abattement des œufs d’helminthes identifiés (Ascaris sp., Capillaria sp., et Trichuris sp.) vers la fin du co-compostage. La phytotoxicité, déterminée par l’effet des extraits hydrosolubles à différents stades de co-compostage sur la germination et la croissance des radicules (Navet, Cresson, Laitue, Luzerne), a diminué et l’indice de germination dépasse 100%, après six mois de co-compostage. La génotoxicité du chrome hexavalent (Cr(VI)) du substrat de co-compostage est corrélée positivement avec la fréquence des micronoyaux (MN). Après six mois de co-compostage le taux des MN diminue avec un taux d’abattement de 70,4% et 77,2% avec l’abattement de la concentration du Cr(VI) avec 58 et 58,6% respectivement pour le mélange A et B. Ceci ouvrira la voie d’utilisation de cet indice comme un indice de maturité des composts. La diminution de la phytotoxicité et la génotoxicté au cours du co-compostage confirme l’état de stabilisation et de la maturité des co-composts, ce qui pemettra l’épandage de ces composts en tant qu’amendement organique des sols sans risque de contamination du système sol-plante. / The co-composting of activated sludge and lignocellulose waste (palm tree waste) was monitored to study the behaviour of two mixtures, referred to as A (1/3 sludge + 2/3 palm waste) and B (1/2 sludge + 1/2 waste palm) for 6 months. The biotransformation was evaluated by physicochemical and spectroscopic analyses. The thermophilic phase is characterized by a rise in temperature, which peaked at 65°C. This is the result of intense microbial activities. The final composts exhibited a higher degree of decomposition than the controls as shown by a decomposition rate of about 40%, decrease of C/N ratio to around 10 and NH4 +/NO3 - ratio below 1. The decrease of aliphatic absorbance bands and the increase of aromatic absorbance bands follow the progress of the humification process. Total extractable lipid was decreased by 43%. The fatty acid methyl esters (FAMEs) from Gram-positive bacteria (i, C15: 0) increased during the thermophilic phase. FAMEs from non-spécific origin (C6 :0, C14 :0) exhibited a decrease toward the end of co-compostin, linear FAMEs from non-specific bacteria underwent a decrease during co-composting. The CPI index thus increased at the end of the composting process, indicating that the final product was proportionally richer in fatty acids of plant origin. Two lignin groups were distinguished by Py-GC-MS. Group 1 contained toluene, 2,4-dimethylbenzene, ethylbenzene, styrene, 1-ethyl-2-methylbenzene, 4-methylphenol and 2-methylnaphthalene; their relative proportions decreased during co-composting. A second group of 4 components showed concentrations that increased with co-composting time: phenol, benzofuran, ethylmethoxyphenol and dimethoxyphenol. The main steroids identified were C27-C29 sterenes and stanols, 5β-cholesta-3-one, cholesta-3,5-diene and 2 thiosteranes. Except for thiosteranes and some of the C27-C29 cholestenes, the relative concentrations decreased during co-composting due to microbial degradation. The changes in steroids during co-composting, was positively correlated with the physico-chemical parameters of mature compost, especially C/N and NH4 +/NO3 - ratios, opening the way for the use of steroids as indicators of pollution and compost maturity. On the selective CTEA medium, 12 active strains of isolated actinobacteria presented a suppressive action against various pathogens. This may justify that a biotic factor is also an important factor contributing to making co-composting substrates hygienic. The degree hygiene reached is confirmed by the reduction in the faecal and total coliforms, and by the abatement of identified helminth eggs (Ascaris sp., Capillaria sp., and Trichuris sp.) towards the end of the process. The phytotoxicity determined by the effect of aqueous extract, at various stages of the co-composting, performed by monitoring the number of germinated seeds and the rootlets growth of turnip, watercress, alfalfa, and lettuce was decreased, and the growth of radicals that have a germination index that exceeds 100% after six months of co-composting. Hexavalent chromium (Cr(VI)) genotoxicity showed a positive correlation with micronucleus (MN) frequency. After six months of co-composting, the MN rate decreased significantly by 70.4 and 77.2% with decreasing Cr(VI) concentration with 58 and 58.6%, for mixtures A and B respectively. That indicates their suitability for use as a maturity index. During co-composting the abatement rate of phytotoxicity and genotoxicity confirme the maturation and stabilization degree of co-composting end products which encourages their recycling in agriculture as a fertilizer for the soil without any contamination of the soil-plant system.
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Wastescape Bhubaneswar & CuttackGudéhn, Oskar, Ringqvist, Linda January 2014 (has links)
This project is a study of the wastescape - a network of waste - of Bhubaneswar and Cuttack in Odisha, India. The study incorporates key locations, e.g. landfills, urban wastelands and waste warehouses; major actors in the formal and informal waste sector; and flows of waste through economic and social systems. Drawing from the studies, multiple interventions within the wastescape are proposed for improvement of the economic, ecologic and social situation. An important aspect of the project is the development of an approach for how to, as architects, work with big, complex, contingent networks; how to map and understand such a system; and how to determine where to intervene. To improve the existing wastescape, interventions must consciously and holistically address multiple scales; levels of formal-informal; and phases within the waste cycle. The study includes a vast amount of possible interventions. Some of the interventions are further detailed to show feasibility; impact on the wastescape; and synergies with other interventions within the wastescape. / Projektet “Wastescape of Bhubaneswar & Cuttack” är en studie av ett nätverk av skräpflöden genom Bhubaneswar och Cuttack i Odisha, Indien. Studien inkorporerar viktiga platser, t.ex. deponier, urbana ödemarker och lokaler för skräphandel; stora aktörer i den formella och informella skräpsektorn; och flöden av skräp genom ekonomiska och sociala system. Utifrån dessa studier, ett flertal interventioner i “the wastescape” föreslås för att förbättra den ekonomiska, ekologiska och sociala situationen. En viktig aspekt av arbetet är utvecklingen av ett sätt att, som arkitekt, arbeta med storskaliga, komplexa och inter-beroende nätverk; hur sådana system kan kartläggas och förstås; samt hur det går att avgöra vart och hur interventioner passar in i “the wastescape”. För att förbättra “the wastescape”, interventioner måste medvetet och holistiskt adressera multipla skalor; nivåer av formell-informell; och faser i skräpets kretslopp. Studien innehåller ett stort nummer av möjliga interventioner. Några av dessa interventioner är ytterligare detaljerade för att visa på genomförbarhet; påverkan på “the wastescape”; och synergier gentemot andra interventioner i “the wastescape”.
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Three Essays on Food Waste Management PlanningArroyo-Rodriguez, Angel Santiago January 2020 (has links)
No description available.
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Sustainable Construction Practices of Intentional Communities: a Pilot Investigation in Loudoun County, Virginia and Frederick County, MarylandShedd, Jason Lee 11 August 2012 (has links)
This project investigated the sustainability of homes within three intentional communities. Semi-structured interview and photographic walkthroughs examined the variability of architectural and technological approaches toward sustainability. These include: passive solar design, green roofs, radiant flooring, composting toilets, ground assist heat pumps, solar water heaters, multiamily units and modular construction. It was hypothesized that variation in sustainable construction is related to socioeconomic status and that economics would be a constraint. This project investigated whether communities were transmitting their practices to wider society, if individuals were copying vernacular architecture and if architectural practices followed individual beliefs regarding sustainability. It was found that the Internet is the main method of conveying these practices; that variability was tied less to individual beliefs than to the communities’ institutional documents; and that copying vernacular architecture was for aesthetics not sustainability. Intentional communities are good models for sustainable development, but knowledge transmission is limited.
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