996 resultados para Urban solid residue
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De-inking sludge is a waste product generated from secondary fibre paper mills who manufacture recycled paper into new paper sheets; it refers directly to the solid residues which evolve during the de-inking stage of the paper pulping process. The current practice for the disposal of this waste is either by land-spreading, land-filling or incineration which are unsustainable. This work has explored the intermediate pyrolysis of pre-conditioned de-inking sludge pellets in a recently patented 20 kg/h intermediate pyrolysis reactor (The Pyroformer). The reactor is essentially two co-axial screws which are configured in such a way as to circulate solids within the reactor and thus facilitate in the cracking of tars. The potential application of using the volatile organic vapours and permanent gases evolved would be to generate both combined heat and power (CHP) located at paper making sites. The results show that de-inking sludge could be successfully pyrolysed and the organic vapours produced were composed of a mixture of aromatic hydrocarbons, phenolic compounds and some fatty acid methyl esters as detected by liquid GC-MS. The calorific value of the oil after condensing was between 36 and 37 MJ/kg and the liquid fuel properties were also determined, permanent gases were detected by a GC-TCD and were composed of approximately 24% CO, 6% CH and 70% CO (v/v%). The solid residue from pyrolysis also contained a small residual calorific value, and was largely composed of mainly calcium based inert metal oxides. The application of applying intermediate pyrolysis to de-inking sludge for both CHP production and waste reduction is in principle a feasible technology which could be applied at secondary fibre paper mills. © 2013 Elsevier B.V. All rights reserved.
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The research presented in this thesis was developed as part of DIBANET, an EC funded project aiming to develop an energetically self-sustainable process for the production of diesel miscible biofuels (i.e. ethyl levulinate) via acid hydrolysis of selected biomass feedstocks. Three thermal conversion technologies, pyrolysis, gasification and combustion, were evaluated in the present work with the aim of recovering the energy stored in the acid hydrolysis solid residue (AHR). Mainly consisting of lignin and humins, the AHR can contain up to 80% of the energy in the original feedstock. Pyrolysis of AHR proved unsatisfactory, so attention focussed on gasification and combustion with the aim of producing heat and/or power to supply the energy demanded by the ethyl levulinate production process. A thermal processing rig consisting on a Laminar Entrained Flow Reactor (LEFR) equipped with solid and liquid collection and online gas analysis systems was designed and built to explore pyrolysis, gasification and air-blown combustion of AHR. Maximum liquid yield for pyrolysis of AHR was 30wt% with volatile conversion of 80%. Gas yield for AHR gasification was 78wt%, with 8wt% tar yields and conversion of volatiles close to 100%. 90wt% of the AHR was transformed into gas by combustion, with volatile conversions above 90%. 5volO2%-95vol%N2 gasification resulted in a nitrogen diluted, low heating value gas (2MJ/m3). Steam and oxygen-blown gasification of AHR were additionally investigated in a batch gasifier at KTH in Sweden. Steam promoted the formation of hydrogen (25vol%) and methane (14vol%) improving the gas heating value to 10MJ/m3, below the typical for steam gasification due to equipment limitations. Arrhenius kinetic parameters were calculated using data collected with the LEFR to provide reaction rate information for process design and optimisation. Activation energy (EA) and pre-exponential factor (ko in s-1) for pyrolysis (EA=80kJ/mol, lnko=14), gasification (EA=69kJ/mol, lnko=13) and combustion (EA=42kJ/mol, lnko=8) were calculated after linearly fitting the data using the random pore model. Kinetic parameters for pyrolysis and combustion were also determined by dynamic thermogravimetric analysis (TGA), including studies of the original biomass feedstocks for comparison. Results obtained by differential and integral isoconversional methods for activation energy determination were compared. Activation energy calculated by the Vyazovkin method was 103-204kJ/mol for pyrolysis of untreated feedstocks and 185-387kJ/mol for AHRs. Combustion activation energy was 138-163kJ/mol for biomass and 119-158 for AHRs. The non-linear least squares method was used to determine reaction model and pre-exponential factor. Pyrolysis and combustion of biomass were best modelled by a combination of third order reaction and 3 dimensional diffusion models, while AHR decomposed following the third order reaction for pyrolysis and the 3 dimensional diffusion for combustion.
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During the drilling of oil and natural gas are generated solid waste, liquid and gaseous. These solid fragments, which are known as cuttings, are carried to the surface through the drilling fluid. Furthermore, this fluid serves to cool the bit, keeping the internal pressure of the well, and others. This solid residue is very polluting, because it has incorporated beyond the drilling fluid, which has several chemical additives harmful to the environment, some heavy metals that are harmful to the environment, such as lead. To minimize the residue generated, are currently being studied numerous techniques to mitigate the problems that such waste can cause to the environment, like addition of cuttings in the composition of soil cement brick masonry construction, addition of cuttings on the clay matrix for the manufacture of solid masonry bricks and ceramic blocks and coprocessing of the cuttings in cement. So, the main objective of this work is the incorporation of cuttings drilling of oil wells, the cement slurry used in the cementing operation of the well. This cuttings used in this study, arising from the formation Pendências, was milled and separated in a sieve of 100 mesh. After grinding had a mean particle sike in order of 86 mm and crystal structure containing phases of quartz and calcite type, characteristic of the Portland cement. Were formulated and prepared slurries of cement with density 13 lb / gal, containing different concentrations of gravel, and realized characterization tests API SPEC 10A and RP 10B. Free water tests showed values lower than 5.9% and the rheological model that best described the behavior of the mixtures was the power. The results of compressive strength (10.3 MPa) and stability (Dr <0.5 lb / gal) had values within the set of operational procedures. Thus, the gravel from the drilling operation, may be used as binders in addition to Portland cement oil wells, in order to reuse this waste and reduce the cost of the cement paste.
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rates in the Brazilian cities, which time there is an inexistent theoretical reflection about public policy statement adding the way of Urban Solid Waste (USW) and tailing integrated management plans in the majorly Brazilian cities. The unappropriated solid waste disposal and final pollution result in a strong socioenvironmental problems and material extravagancies that should be used to recycling and reusing waste material, besides bringing immense challenges for the thematic Strategy Urban and Environmental Management it considers the Sustainable City Model. Moreover, this labor projects a discussion about USW problematic through legally and environmentally point of view, including the public environmental policy and the social technologies as resolution tactics. At that time, it reports rights, scientific articles, documents and Environmental Law Doctrine on findings thematic studies, also the propose displays an interdisciplinary research methodology which combines bibliographic method - focusing theory aspects of the legally environmentally guiding principle, public policy and social technologies. Those are theorist features very important to create a Municipal Integrated Solid Waste Management Plan (PMGIRS) - modus operandi of the Federal Law n. 12.305/2010 (National Solid Waste Policy - PNRS). That policy is interesting to receive financial resources from federal government (Cities Ministry; idem, Federal Decree n. 7.404/2010 and Federal Law n. 10.257/2001) helping the preservation of the environment, regional development, generation of jobs and income (art. 6º), in addition broadening spreading’s private companies dedicated to waste management. Consequently, the PNRS contains a set of guidelines and general procedures; it should be an operation of this legal policy contextualized by Social Technologies theory (TS) into social issues, legal, economic and environmental aspects. Therefore, this research notes the possibility of public policy statement implementation over and done with the PNRS by the terms of development and sustainability in the urban space.
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The hydrothermal liquefaction(HTL) of algal biomass is a promising route to viable second generation biofuels. In this investigation HTL was assessed for the valorisation of algae used in the remediation of acid mine drainage (AMD). Initially the HTL process was evaluated using Arthrospira platensis (Spirulina) with additional metal sulphates to simulate metal remediation. Optimised conditions were then used to process a natural algal community (predominantly Chlamydomonas sp.) cultivated under two scenarios: high uptake and low uptake of metals from AMD. High metal concentrations appear to catalyse the conversion to bio-oil, and do not significantly affect the heteroatom content or higher heating value of the bio-oil produced. The associated metals were found to partition almost exclusively into the solid residue, favourable for potential metal recovery. High metal loadings also caused partitioning of phosphates from the aqueous phase to the solid phase, potentially compromising attempts to recycle process water as a growth supplement. HTL was therefore found to be a suitable method of processing algae used in AMD remediation, producing a crude oil suitable for upgrading into hydrocarbon fuels, an aqueous and gas stream suitable for supplementing the algal growth and the partitioning of most contaminant metals to the solid residue where they would be readily amenable for recovery and/or disposal.
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The hydrothermal liquefaction(HTL) of algal biomass is a promising route to viable second generation biofuels. In this investigation HTL was assessed for the valorisation of algae used in the remediation of acid mine drainage (AMD). Initially the HTL process was evaluated using Arthrospira platensis (Spirulina) with additional metal sulphates to simulate metal remediation. Optimised conditions were then used to process a natural algal community (predominantly Chlamydomonas sp.) cultivated under two scenarios: high uptake and low uptake of metals from AMD. High metal concentrations appear to catalyse the conversion to bio-oil, and do not significantly affect the heteroatom content or higher heating value of the bio-oil produced. The associated metals were found to partition almost exclusively into the solid residue, favourable for potential metal recovery. High metal loadings also caused partitioning of phosphates from the aqueous phase to the solid phase, potentially compromising attempts to recycle process water as a growth supplement. HTL was therefore found to be a suitable method of processing algae used in AMD remediation, producing a crude oil suitable for upgrading into hydrocarbon fuels, an aqueous and gas stream suitable for supplementing the algal growth and the partitioning of most contaminant metals to the solid residue where they would be readily amenable for recovery and/or disposal.
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In the industrial production of soluble coffee, huge amounts of extracted coffee residues are generated; onaverage, for eachtonne of green coffee extracted, 480 kg of coffee ground waste is produced. This is a solid residue currently used to generate energy at the steam boilers from the soluble coffee industry. Some is also used or as fertilizer on agriculture fields. Seeking a better end use, the work reported here aimed to study the viability of hydrolyzing the coffee ground residue for the production of carbohydrates. Hydrolysis was undertaken with hydrochloric acid at different temperatures and pressures, using a water bath or autoclave.An enzymatic hydrolysis with Viscozyme Lwas developed using Whatman filter paper No1 and the optimal conditions were determined using a rotational central composite experimental design (DCCR).The best conditions to hydrolyze filter paper cellulose were 50 FBG (Fungal β-glucanase) of Viscozyme L at pH 4.0 for 1.0 h and 45 ºC. The ground coffee was hydrolyzed under the same conditions as described above for filter paper, however this enzymatic hydrolysis was not efficient. A combination of enzymatic hydrolysis as a pre-treatment for the ground coffee followed by acid hydrolysis using HCl conducted in an autoclave (120 C for 2.0 h) resulted in higher production of glucose as analyzed by HPLC. Another end use of the ground coffee evaluated was as source of substrate in the culture medium to grow Botryosphaeria rhodina MAMB-05 to produce the enzymes laccase and cellulase. Highest enzyme titres obtained were with 8% (w/v) coffee grounds to which was added a minimum salts medium(Vogel), under agitation conditions (180 rpm) at 28ºC. The phenolic compounds present in the coffee grounds appear to have induced laccase by Botryosphaeria rhodina.
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A qualidade dos produtos alimentares e a sua influência sobre a nutrição e a saúde humana tem vindo a merecer um lugar de destaque na comunidade científica. O conceito de alimento funcional tem adquirido grande importância hoje em dia, em particular os alimentos com compostos bioactivos. O Cardo (Cynara cardunculus L.) é uma planta herbácea originária da região mediterrânea usada essencialmente na coagulação do leite, e por muitos considerada um medicamento popular, devido aos seus efeitos terapêuticos. Este trabalho teve como objectivo estudar o efeito de diferentes condições de secagem da flor de cardo, na composição em ácidos fenólicos, bem como em polissacarídeos. Era ainda objectivo tentar identificar possíveis compostos que pudessem ser utilizados como marcadores de autenticidade do queijo da serra. Neste trabalho foi usada uma amostra de flor de cardo liofilizado e três amostras secadas, a diferentes temperaturas (40, 50 e 60ºC). A análise do resíduo sólido da flor do cardo, por cromatografia gasosa, permitiu identificar a presença de açúcares constituintes de polissacarídeos pécticos. A análise por HPLC, dos extratos metanólicos e cetónicos, revelaram a presença de ácidos hidroxibenzóicos e hidroxicinâmicos na flor do cardo. A amostra mais rica nestes compostos foi a amostra secada a 50ºC. O aumento da temperatura de secagem originou uma diminuição de ácidos fenólicos.
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As proteases constituem 60-65% do mercado global das enzimas industriais e são utilizadas na indústria de alimentos no processo de amaciamento de carne, na síntese de peptídeos, preparo de fórmulas infantis, panificação, cervejarias, produtos farmacêuticos, diagnósticos médicos, como aditivos na indústria de detergentes e na indústria têxtil no processo de depilação e transformação do couro. Proteases específicas produzidas por micro-organismos queratinolíticos são chamadas de queratinases e distinguem-se de outras proteases pela maior capacidade de degradação de substratos compactos e insolúveis como a queratina. Atualmente, processos que apontem o uso total das matérias-primas e que não resultem em impactos negativos ao meio ambiente tem ganhado destaque. Dentro desta temática, destacam-se a reutilização da farinha de penas residual durante o cultivo do Bacillus sp. P45 para produção de proteases e a biomassa residual de levedura, ambas com elevados teores de proteínas, podendo ser utilizadas no cultivo do Bacillus sp. P45 para obtenção de proteases. O objetivo deste trabalho foi obter a enzima queratinase purificada em grandes quantidades, sua caracterização, bem como a sua aplicação em processos de coagulação enzimática do leite para o desenvolvimento de um queijo cremoso enriquecido com farinha de chia e quinoa. Além disso, aplicar diferentes coprodutos para produção de enzimas proteolíticas e queratinolíticas. A presente tese foi dividida em quatro artigos: no primeiro foi realizado a obtenção da queratinase purificada em maiores quantidades e a determinação dos parâmetros de estabilidade térmica e a influência de componentes químicos na atividade enzimática. A obtenção da enzima em maiores quantidades alcançou fatores de purificação de 2,6, 6,7 e 4,0 vezes, paras 1º SAB, 2º SAB e diafiltração, respectivamente. A recuperação enzimática alcançou valores de 75,3% para o 1º SAB, 75,1% no 2º sistema e 84,3% na diafiltração. A temperatura de 55ºC e o pH 7,5 foram determinados como ótimos para atividade da enzima queratinase. O valor da energia de desativação (Ed) médio foi de 118,0 kJ/mol e os valores de z e D variaram de 13,6 a 18,8ºC, e 6,9 a 237,3 min, respectivamente. Além disso a adição de sais (CaCl2, CaO, C8H5KO4 e MgSO4) elevou a atividade da enzima na presença destes compostos. O segundo artigo apresenta a aplicação da queratinase como coagulante de leite bovino e sua aplicação na obtenção de queijo cremoso enriquecido com chia e quinoa. A enzima mostrou atividade de coagulação semelhante ao coagulante comercial, na concentração de 30mg/mL. A enzima purificada foi empregada de forma eficiente na fabricação do queijo cremoso, que apresentou valores de pH de 5,3 e acidez de 0,06 a 0,1 mol/L, com elevação durante os 25 dias de armazenamento. O terceiro artigo apresenta o perfil do queijo cremoso enriquecido com farinha de chia e quinoa, o qual apresentou alto índice de retenção de água (>99,0%) e baixos valores de sinérese (<0,72%). Elevados teores de fibras foi verificado (3,0 a 5,0%), sugerindo seu consumo como fonte de fibras. As análises microbiológicas foram de acordo com a legislação vigente. Na análise sensorial foi verificado altos valores de suavidade ao paladar e verificado maiores valores de consistência e untabilidade nas amostras com maiores concentrações de nata e quinoa. O quarto artigo traz a extração de β-galactosidase por ultrassom e o uso da biomassa residual da levedura, bem como o uso de farinha de penas residuais como substrato para obtenção de proteases. O ultrassom foi eficiente para ruptura celular e extração de β-galactosidase, apresentando alta atividade (35,0 U/mL) e rendimento (876,0 U/g de biomassa). A maior atividade proteolítica (1300 U/mL em 32 h) e queratinolítica (89,2 U/mL) verificadas ocorreram utilizando-se a biomassa e a farinha de penas residuais, respectivamente. Maior produtividade proteolítica (40,8 U/mL/h) foi verificado no meio utilizando biomassa residual como substrato. Já a maior produtividade queratinolítica (2,8 U/mL/h) foi alcançada utilizando farinha de penas reutilizada.
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Tese (doutorado)—Universidade de Brasília, Centro de Desenvolvimento Sustentável, 2013.
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2014
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Los residuos sólidos como consecuencia directa de las actividades humanas, han representado un reto desde sus inicios, de ahí se empezaron a desarrollar técnicas y prácticas para garantizar una adecuada gestión de los residuos, nuestros primeros ancestros encontraron en los botaderos a cielo abierto la solución más fácil para disponer los desechos de animales y residuos de comida en sitios cercanos a sus viviendas, por ejemplo, los griegos poseen registros de la inauguración del primer relleno municipal en la ciudad de Atenas hace más de 2000 años. La evolución de las culturas, la revolución industrial y el crecimiento poblacional acelerado han modificado no solo la composición sino también la cantidad de los residuos sólidos producidos, haciendo cada día más difícil su adecuada gestión debido a su alto grado de toxicidad, la ausencia de materiales biodegradables y su volumen, traduciendo esto en un gran impacto. El panorama no es muy alentador y los pronósticos emitidos por el Banco Mundial prevén que para el año 2025 los niveles mundiales de residuos sólidos urbanos alcanzaran 2,2 millones de toneladas por año. Basada en el interés por la adecuada gestión de los residuos y la disminución del impacto ambiental de las empresas Coraseo S.A y Seacor S.A, la presente investigación busca seleccionar la metodología y/o tecnología más apropiada teniendo en cuenta las condiciones económicas, logísticas y de infraestructura de la empresa y la comunidad involucrada. En primera instancia se estudió en profundidad el panorama empresarial y posteriormente se seleccionó un grupo de cuatro propuestas para la transformación y aprovechamiento de los residuos sólidos que fueron evaluadas a nivel económico, normativo, medio ambiental. Los datos analizados sugieren entre otras cosas, un robustecimiento del marco legal ambiental colombiano y mundial, una mayor colaboración económica de los organismos internacionales y las entidades bancarias y finalmente una reducción en los costos de las tecnologías disponibles para el aprovechamiento de los residuos sólidos, haría posible el sueño de las sociedades de gestionar efectivamente los residuos sólidos generando el menor impacto ambiental posible y en el caso del grupo empresarial Cordobés lograr innovar y emprender con un proyecto eco eficiente como el que se evaluó.
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Enzyme production is a growing field in biotechnology and increasing attention has been devoted to the solid-state fermentation (SSF) of lignocellulosic biomass for production of industrially relevant lignocellulose deconstruction enzymes, especially manganese-peroxidase (MnP), which plays a crucial role in lignin degradation. However, there is a scarcity of studies regarding extraction of the secreted metabolities that are commonly bound to the fermented solids, preventing their accurate detection and limiting recovery efficiency. In the present work, we assessed the effectiveness of extraction process variables (pH, stirring rate, temperature, and extraction time) on recovery efficiency of manganese-peroxidase (MnP) obtained by SSF of eucalyptus residues using Lentinula edodes using statistical design of experiments. The results from this study indicated that of the variables studied, pH was the most significant (p < 0.05%) parameter affecting MnP recovery yield, while temperature, extraction time, and stirring rate presented no statistically significant effects in the studied range. The optimum pH for extraction of MnP was at 4.0-5.0, which yielded 1500-1700 IU kg (1) of enzyme activity at extraction time 4-5 h, under static condition at room temperature. (C) 2011 Elsevier Ltd. All rights reserved.
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Solid-state C-13 nuclear magnetic resonance (NMR) with cross-polarisation (CP) and magic-angle-spinning (MAS) was used to: (a) examine the changes in carbon (C) composition of windrowed harvest residues during the first 3 years of hoop pine plantations in subtropical Australia; (b) assess the impacts of windrowed harvest residues on soil organic matter (SOM) composition and quality in the 0-10 cm soil layer. Harvest residues were collected from 0-, 1-, 2- and 3-year-old windrows of ca. 2.5 m width (15 m apart for 0-, 1- and 2-year-old sites and 10 m apart for 3-year-old site). Soils from the 0 to 10 cm soil layer were collected from the 1-, 2- and 3-year-old sites. The 13C NMR spectra of the harvest residues indicated the presence of lignin in the hoop pine wood, foliage and newly incorporated organic matter (NIOM). Condensed tannin structures were found in the decay-resistant bark, small wood and foliage, but were absent in other residue components and SOM. The NMR spectra of small wood samples contained condensed tannin structures because the outer layer of bark was not removed. NIOM showed a shift from foliage-like structures (celluloses) to lignin-type structures, indicating an incorporation of woody residues from the decomposing harvest residues. Suberins were also present in the small wood, foliage and bark. The 13C CP NMR spectra of SOM indicated that in areas where windrows were present, SOM did not show compositional changes. However, an increase in SOM quality under the windrows in the second year after their formation as characterised by the alkyl C/O-alkyl C (A/O-A) ratio was mainly due to inputs from the decomposition of the labile, readily available components of the windrowed harvest residues. (C) 2002 Published by Elsevier Science B.V.
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Sarcosaprophagous macroinvertebrates (earthworms, termites and a number of Diptera larvae) enhance changes in the physical and chemical properties of organic matter during degradation and stabilization processes in composting, causing a decrease in the molecular weights of compounds. This activity makes these organisms excellent recyclers of organic matter. This article evaluates the succession of insects associated with the decomposition of solid urban waste separated at the source. The study was carried out in the city of Medellin, Colombia. A total of 11,732 individuals were determined, belonging to the classes Insecta and Arachnida. Species of three orders of Insecta were identified, Diptera, Coleoptera and Hymenoptera. Diptera corresponding to 98.5% of the total, was the most abundant and diverse group, with 16 families (Calliphoridae, Drosophilidae, Psychodidae, Fanniidae, Muscidae, Milichiidae, Ulidiidae, Scatopsidae, Sepsidae, Sphaeroceridae, Heleomyzidae, Stratiomyidae, Syrphidae, Phoridae, Tephritidae and Curtonotidae) followed by Coleoptera with five families (Carabidae, Staphylinidae, Ptiliidae, Hydrophilidae and Phalacaridae). Three stages were observed during the composting process, allowing species associated with each stage to be identified. Other species were also present throughout the whole process. In terms of number of species, Diptera was the most important group observed, particularly Ornidia obesa, considered a highly invasive species, and Hermetia illuscens, both reported as beneficial for decomposition of organic matter.