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EFFEKTIVISERING AV MATERIALFLÖDET : – HUR KAN ETT FÖRETAG FÖRBÄTTRA SINA EKONOMISKA PARAMETRAR? / Optimization of the material flow : – How can a manufacturing company improve its economic parameters?Merkouris, Dimitrios January 2015 (has links)
The automotive industry has given over the last seven decades to the industrial world a sustained demand for vehicles. It is classed as one of the largest industries in the world and an industry that most use and develop new technologies with the goal to reduce their costs and increase their productivity.The Japanese philosophy that calls from the west-world for Lean Management is based on, among other things, the elimination of the "muda" which translates as waste through continuous efforts aimed at achieving a robust manufacturing. To achieve this, uses several methods and tools and among others is the Just-In-Time approach the most abundant. JIT means the right material will be in the right place at a specific time. This study will most be focused on a strategy that is considered the most extreme application of the concept, namely the Just-In-Sequence strategy in which the components are delivered in the right time and in the right sequence in a pull system manufacturing there the goal is to see if the lead times and resource need can be minimized.To test the appropriate theory takes the study place at Volvo Cars in Torslanda, Sweden. Volvo Cars manufactures some of the most popular cars in the world, with production in Europe, Asia, and from 2018 also in the United States. The company implements the Lean methods and especially JIT but also JIS in some parts of the assembly.This study was done on the engine department there the engines arrive from the supplier in a rack that runs further to the different buffers and from there to the production line for final assembly.The purpose was to investigate and report on how the company could through using of the JIS strategy affect the material flow as well as which economic benefits had this implementation resulted.The study took into account both sequencing at the supplier and sequencing in the plant after the arrival. Both methods resulted a more efficient flow of materials in which a reduction in the need of resources was noted. The sequencing at the supplier proved to be even more advantageous, as in most of the cases, production costs less at suppliers but also the reduction in capital was radically.IITo achieve a perfect sequence requires close cooperation with the suppliers and a quite big investment to create robust processes that eliminates the error probability.The main recommendation to Volvo Cars is to mostly focus on the big picture than on each plant individually. To achieve a more efficient flow and a better result for the entire organization is something that should be given priority even if a facility would then get a worse result. Finally, it is recommended to Volvo Cars to invest in a Just-In-Sequence strategy which bring benefits such as freeing up operative area in the factory, but most important of all, it reduces the lead times and the resource-costs. / Fordonsindustrin har under de senaste sju decennierna gett till industriella världen en oförminskad efterfrågan på fordon. Den klassas som en utav de största industrierna i världen samt en industri som mest använder och utvecklar ny teknik med mål att sänka sina kostnader och öka sin produktivitet.Den japanska filosofin som västervärlden kallar för Lean management grundar på bland annat eliminering av ”muda” som översätts som slöseri genom ett kontinuerligt arbete som siktar till att uppnå ett robust tillverkningssystem. För att uppnå detta används flera metoder och verktyg och bland andra är Just-In-Time metoden den mest förekommande. JIT innebär att rätt material ska vara på rätt plats på en specifik tid. I denna studie kommer mest läggas fokus på en strategi som anses av de flesta företag vara den mest extrema tillämpningen av konceptet, nämligen Just-In-Sequence strategin där komponenterna levereras helt enkelt i rätt tid och i rätt sekvens i ett dragande system och målet är att se om ledtiderna och resursbehovet kan minimeras.För att prova den lämpliga teorin äger studien rum på Volvo Cars i Torslanda. Volvo Cars tillverkar några utav de mest efterfrågade bilarna i världen med produktion i Europa, Asien och från och med 2018 i USA. Företaget använder sig av de ovannämnda Lean metoderna som JIT men även JIS på vissa delar av monteringen.Denna studie skedde specifikt på motoravdelningen där motorer ankommer ifrån leverantören i rack som vidare körs till olika buffertar och därifrån till produktionsbandet för slutmonteringen.Syftet var att undersöka och redogöra för hur företaget kan med hjälp av JIS-strategin påverka företagets materialflöde samt vilka ekonomiska fördelar hade denna implementering medfört.Studien tog hänsyn till både försekvensering hos leverantören och sekvensering efter ankomsten till fabriken. Båda två metoderna resulterade i ett effektivare materialflöde där en minskning av behövande resurser märktes. Sekvenseringen hos leverantören visade sig vara ännu fördelaktig då i de flesta av fallen är tillverkningskostnaderna mindre hos leverantörer men även minskning av bundet kapital var radikalt. Att nå en perfekt sekvens kräver nära samarbete med leverantören och en ganska stor investering för att skapa robusta processer som eliminerar felsannolikheten.Den huvudsakliga rekommendationen till Volvo Cars är att fokusera mest på helheten än på varje fabrik individuellt. Att nå ett effektivare flöde och ett bättre resultat för hela koncernen är något som borde prioriteras även om en anläggning skulle i så fall få ett mindre bra resultat. Slutligen rekommenderas till Volvo Cars att investera i en Just-In-Sequence strategi något som medför fördelar genom att frigöra viktig yta i fabriken men viktigaste av allt, genom att minska sina ledtider och sina resurskostnader.
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Data uncertinties in material flow analysis.Local case study and literature survey.Danius, Lena January 2002 (has links)
<p>The aim of this thesis is to discuss and analyse the influenceof data uncertainties with regard to the reliability of materialflow analysis (MFA) studies. MFA, as a part of environmentalsystems analysis, is a method belonging to the research field ofindustrial ecology and more specifically industrial metabolism.As such, the method strives at giving a holistic view of thecomplex world we live in, in order to reduce negativeenvironmental impact. Among other things, MFA studies have beenproposed to be useful for priority setting and following up inmunicipalities.</p><p>Serving as a starting point is a local case study of flows ofnitrogen in a Swedish municipality, Västerås. The casestudy has been performed using the ComBoxmodel. The years studiedare 1995 and 1998. The main sectors in society emitting nitrogento water were identified as the agricultural and householdsectors. The dominating sectors emitting nitrogen to air wereidentified as the agricultural, transport and infrastructuresectors.</p><p>As a basis for discussing data uncertainties qualitatively andquantitatively a literature survey was performed. 50 articles andbooks were identified as in some way or another dealing with datauncertainties in MFA. The literature survey showed that theuncertainties for results from a MFA study might vary between±30 % and a factor 10 depending on what kind of parameter isinvestigated. Only one method was found that dealt with datauncertainties in MFA in a complete way; a model developed byHedbrant and Sörme (HS model).</p><p>When applying the HS model to the case study of nitrogen flowsin Västerås, it was found that when uncertaintyintervals were calculated the possible conclusions changed. Ofthe two pair of flows compared in relation to priority setting,none of the earlier conclusions remained. Of the three flowsanalysed in relation to following up, only the flow from onepoint source supported the same conclusion when uncertainty wasconsidered.</p><p>In all, it is concluded that data uncertainties in MFAanalysis are an important aspect and that further research isneeded in order to improve input data quality estimations andframeworks for determining, calculating and presenting data, datauncertainties and results from MFA studies. However, theunderlying reality remains, e.g. that management of materialflows are important for understanding and reducing the negativeenvironmental impact. Thus, MFA is one useful tool in thiswork.</p><p><b>Keywords:</b>data uncertainties, sensitivity analysis,Material flow analysis, MFA, method to determine datauncertainties, case study, ComBox model, nitrogenflows.</p>
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Resurseffektivisering : På ICA Sverige AB:s centrallager / Resource efficiency : At ICA Sverige AB:s central warehouseGillmén, Martin January 2016 (has links)
Logistik är den del av ett företag som påverkar företagets resultat på ett mycket betydande sätt. Kunden ställer krav på att få sin produkt levererad på en viss tidpunkt och om produkten då inte levereras på utsatt datum kan detta leda till en förlorad kund och därmed förlorade framtida inkomster. För att lyckas leverera till kund på utsatt tid krävs det att många processer fungerar väl ihop och att ett välplanerat system är implementerat. Denna rapport är skriven på ICA Sverige ABs centrallager i Kungälv och handlar om effektivisering. Mer specifik effektivisering av användningen av truckar. Genom att förkorta körsträckor och eliminera icke-värdeskapande körsträckor kan man få ett mer effektivt lager. Jag har samlat in relevant data så som genomsnittlig sträcka per order samt information om vilka lagergångar som är mest trafikerade för att veta vart i lagret som problemet finns och varför det uppstått. Zon-indelning är en metod som är känd för att minska körsträckor på ett lager. En implementering av metoden underlättas också av att ICA i dagsläget har sorterat artiklarna på ett sådant sätt att de första tio lagergångarna är fyllda med SRS-backar. Det är en metod som inte bara förkortar körsträckor utan och effektiviserar materialhantering. Teoridelen av arbetet görs för att får en större insikt i ämnen logistik samt för att hitta och benämna de metoder som påverkar logistiken i ett företag. Olika typer av materialhanteringsmetoder, lagringsmetoder, artikelplaceringsmetoder är exempel på vad som beskrivs djupare. Analysen har gjort för att analysera och koppla samman de teorier som använts till de problem som behandlas i rapporten men även reflektioner och tankar kring varför teorierna har använts. Rapporten har skrivits på ICA Sverige ABs centrallager i Kungälv och har koncentrerats till färskvaruavdelningen där problemet med långa körsträckor har uppkommit. / Logistics is that part of a company that affects the company’s efficiency in a considerable way. The customer has demands on the product to have it delivered on a specific date and if the product isn’t delivered on that date the consequences may result in a loss of a customer and therefore a loss of income. To be able to deliver the product on the specific date to the customer there’s a couple of processes that need to work flawlessly together and that a well worked out system is implemented. This report is written at ICA Sverige AB’s central warehouse is Kungälv, Sweden. It surrounds the subject of efficiency in warehousing and usage of lift trucks. Thru minimizing the driving distance of the lift trucks and eliminating not-value processes you can create a more efficient warehouse. I’ve gathered information regarding average distance per completed order and information regarding which of the warehouse aisles is the busiest to get an insight in where the problem is and why it has occurred. Zone-picking is a method that is known to minimize lift truck distances in a warehouse. An implementation of this method at ICA is facilitated by the fact that the articles already are sorted in a way that the first ten aisles are filled with plastic crates. It’s a method that not only minimizes the lift truck distances but also make the material handling more efficient. The theory part of the report is done to get a bigger insight in the subject of logistics but also to find and mention methods that affect the logistics in a company. Different types of material handling methods, storage methods and article placement methods are examples of methods describe. The analyzing part of the report has been done to connect mentioned theories to main problems that the report is surrounding but also includes reflections and thoughts about why the theories have been used. The report has been written at ICA Sverige AB’s central warehouse in Kungälv and has been focused on the fresh food compartment of the warehouse where problems with long distances for the lift trucks has occurred.
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Modell för bestämning av tillverkningskostnad med utgångspunkt från materialflöden i produktion : En fallstudie på Alderholmens mekaniskaKrstic, Nikola, Eriksson, Fanny January 2019 (has links)
Inledning: Marknadstillväxten har gått framåt senaste åren och företag bör hitta konkurrensfördelar för att fortsätta vara lönsamma. Priser bör anpassas efter marknaden och vetskap om tillverkningskostnad blir viktigt för tillverkande företag. För att beräkna tillverkningskostnad för produkter kan självkostnadskalkylering och totalkostnadsmodellen användas. Ett materialflöde i en produktion består av processer som innefattar hantering, förflyttning och lagring av material. Studien har inte funnit någon tidigare forskning eller modell som förklarar relationen mellan materialflöden och tillverkningskostnad på en detaljerad nivå vilket motiverar studien. Syfte: Syftet med arbetet var att utforma och utvärdera en modell för bestämning av tillverkningskostnad med utgångspunkt från materialflöden i produktion med avseende på lagring, transport och tillverkningsoperationer. Metoder: En abduktiv ansats har använts för att besvara syftet och frågeställningar där teori och empiri har inhämtats parallellt under arbetets gång. I studien har teori och empiri lagt grund för kostnadsfaktorer som påverkar tillverkningskostnaden. Utformning av modell för bestämning av tillverkningskostnad: I studien har teoretiska och empiriska undersökningar utförts för att redogöra för olika kostnadsfaktorer som påverkar tillverkningskostnaden. Modellen använder tre aktiviteter för att kategorisera identifierade kostnadsfaktorer i ett materialflöde: operation, lagring och transport. Tillämpning och utvärdering av modell: Modellen tillämpades på fallföretaget Alderholmens mekaniska. Efter tillämpningen utvärderades modellen där styrkor och utvecklingsmöjligheter presenterades. Slutsats: Studiens bidrag är en modell för beräkning av tillverkningskostnad med utgångspunkt från materialflödet i produktionen. Modellen presenterar vilka faktorer som påverkar tillverkningskostnaden. Kapitlet avslutas med rekommendationer till framtida studier för att utöka kunskapen inom ämnet.
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Material flow analysis and CO2 footprint in lumber from managed Brazilian Amazon rainforests. / Análise de fluxo de massa e pegada de CO2 em madeira serrada de florestas manejadas na Amazônia brasileira.Numazawa, Camila Thiemy Dias 29 October 2018 (has links)
Using wood produced under forest management in the Amazon has been proposed as a way of preserving the ecosystem, generating jobs and to aid in climate change mitigation by using wood products as carbon stock and through CO2 uptake from the atmosphere during forest regrowth. However, the scarcity of research based on primary data of Amazonian lumber incorporated into construction can unknowingly lead to incorrect forest management and consequently forest destruction. Besides, it is necessary to verify the real environmental impacts. Two approaches were applied in this research to evaluate the wood product chain: material flow analysis and CO2 footprint calculation of managed Amazonian lumber. The research quantified the resource efficiency and CO2 footprint based on residue generation during the raw extraction in 5 forest plots in State of Pará, followed by the lumber production and the end-of-life phases, giving the CO2 balance between the emissions from residue decomposition and the CO2 uptake during forest regrowth, disregarding the energy consumption. Results indicated that the large quantities of logging residues are the main source of CO2 emissions in the material flow from selective logging, ranging from 9% to 36% of the initial forest biomass, while timber logs represented between 4% and 11%. Logging residues ranged from 2.9 t t-1 to 3.1 t t-1 per tonne of log. Combined with an average sawmill lumber yield of 54%, wastage rate values increased to between 5.7 t t-1 and 6.6 t t-1, resulting in a CO2 footprint of managed Amazonian lumber ranging between -6.6 tCO2 t-1 for reduced impact logging as carbon stock, to emissions of 6.1 tCO2 t-1 from cradle-to-gate for conventional logging. From cradle-to-grave the total CO2 footprint of lumber is estimated to range from neutral to 7.5 tCO2 t-1. Resource efficiency ranged from 13% to 15%. In this study, only the forest under reduced impact logging was able to fully recover its initial aboveground biomass, showing that in most cases regulations in the New Forest Code for Amazon forest management may not ensure sustainable logging, leading to forest destruction. Policies need to be improved and integrated with results from empirical research based on primary data to achieve sustainable exploitation of the Amazon forest. / O processo seletivo de utilização da madeira de manejo florestal na Amazônia tem sido proposto como forma de conservação e preservação do ecossistema, associada a geração de empregos e à mitigação de mudanças climáticas, pelo estoque de carbono dada a absorção de CO2 da atmosfera durante o crescimento da floresta. No entanto, a limitação de pesquisas baseadas em dados primários sobre madeiras amazônicas incorporadas na construção civil pode levar, inconscientemente, ao manejo florestal incorreto e, consequentemente, à destruição da floresta no contexto original e de reais impactos ambientais provocadas por ações inadequadas. Duas abordagens foram aplicadas nesta pesquisa para avaliar a cadeia de produtos de madeira: análise de fluxo de material e cálculo da pegada de CO2 da madeira manejada na Amazônia. A pesquisa analisou a eficiência dos recursos e a pegada de CO2 com base na geração de resíduos durante a extração em 5 florestas no Estado do Pará, produção madeireira e o fim de vida, proporcionando o balanço de CO2 entre as emissões da decomposição de resíduos e a absorção do CO2 durante a recomposição florestal, desconsiderando a energia consumida. Os resultados indicaram que o expressivo volume de resíduos florestais é a principal fonte de emissões de CO2 no fluxo de material proveniente da extração seletiva, variando de 9% a 36% da biomassa florestal inicial, enquanto os troncos de madeira representam entre 4% e 11%. Os resíduos de exploração florestal variaram de 2,9 a 3,1 t de resíduos por tonelada de tora. Combinado com um rendimento médio de madeira de serraria de 54%, os valores da taxa de desperdício aumentaram para entre 5,7 t e 6,6 t de resíduos por tonelada de tora e madeira serrada, resultando em uma pegada de CO2 variando entre -6,6 tCO2 t-1 (exploração de impacto reduzido) considerado estoque de carbono e as emissões de 6,1 tCO2 t-1 do berço à porta. No final da vida útil, estima-se que a pegada total de CO2 da madeira entre o berço e o túmulo é de neutra (exploração de impacto reduzido) a 7,5 tCO2 t-1, com uma eficiência de recursos variando de 13% a 15%. Neste estudo, apenas a floresta sob prática de extração de impacto reduzido foi capaz de recuperar totalmente sua biomassa inicial acima do solo, mostrando que as regulamentações do Novo Código Florestal para o manejo da florestal amazônica pode não garantir a sustentabilidade de uso do recurso florestal para aquela exploração que não esteja alicerçada dentro desse contexto de conservação da floresta original. As políticas precisam ser melhoradas, integradas e dinâmicas com base em resultados derivados de pesquisas empíricas baseadas em dados primários garantindo a exploração sustentável na Amazônia.
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Inventário de materiais, energia e emissões dos gases de efeito estufa na vida útil de máquinas agrícolas / Inventory of materials, energy and greenhouse gases emissions in life cycle of agricultural machineryMantoam, Edemilson José 21 June 2016 (has links)
A questão energética, associada às mudanças climáticas e à dependência dos recursos naturais é um dos principais desafios do século XXI. A necessidade de produzir alimentos, para atender a crescente demanda da população, requer o aumento da utilização de máquinas e equipamentos, demandando maior quantidade de energia e causando emissões dos gases de efeito estufa. Fontes de materiais e de energia são consumidas ao longo do ciclo de vida do produto, portanto é importante reduzir a demanda dessas fontes e aperfeiçoar o uso de recursos pelo reuso, reciclagem e materiais renováveis, além da preservação do ambiente. No sistema de produção agrícola, as máquinas agrícolas são consideradas fundamentais para produção de biomassa. A análise de energia em máquinas agrícolas tem sido feita, porém com dados de indicadores da década de 1960. Estudos de energia incorporada e emissões em máquinas agrícolas devem ser feitos, devido à importância do sistema de produção de bioenergia na economia, além da otimização do consumo em operações necessárias à obtenção do produto. Esse estudo propôs determinar o inventário de materiais, energia incorporada e emissões dos gases de efeito estufa em máquinas agrícolas. Foram avaliadas oito máquinas: colhedora de café, pulverizador autopropelido, semeadora-adubadora, colhedora de grãos, trator 55 kW, trator 90 kW, trator 172 kW e trator 246 kW, em seus ciclos de vida útil. Tais sidos adotados segundo três fontes distintas. Os dados foram coletados em uma montadora multinacional, em suas unidades localizadas nos municípios de Piracicaba e Sorocaba, Estado de São Paulo e no município de Curitiba, Estado do Paraná, Brasil. Para cada máquina foi contabilizado o consumo dos insumos diretos utilizados na fase de montagem, e também o consumo dos insumos utilizados na fase de manutenção. Os dados de consumo dos insumos foram processados apresentando os fluxos de materiais utilizados, os quais foram multiplicados pelo seu índice de energia incorporada e fator de emissões, resultando na energia incorporada e nas emissões dos gases de efeito estufa, requeridos pelo sistema de produção. Os resultados apresentaram que a energia incorporada e emissões foram maiores no ciclo de vida indicado pelo fabricante, para colhedora de café, pulverizador, semeadora-adubadora, colhedora de grãos, e no ciclo de vida indicado pelo (BRASIL, 2010), para os tratores 55 kW, 90 kW, 172 kW e 246 kW, respectivamente. Para avaliação ambiental em tratores, equações foram fornecidas para demanda de energia e emissões pela massa (energia = -0,0057 massa + 129,2669), (emissões = -0,0003 massa + 5,9845) e pela potência motor (energia = -14,7672 potência motor + 6.507,9639), (emissões = -0,6861 potência motor + 299,1242). / The energy subject, associated with global climate changes and the environment dependency is one of the main challenges of 21st century. The need to produce food, to meet the growing demand of the population, requires increased use of machinery and equipment, demanding more energy and raising greenhouse gases emissions. Materials and energy sources are consumed during the product life cycle, so it is important to reduce the demand for these sources and optimizing the use of resources by reuse, recycling and renewable materials, plus environment preservation. At agricultural production system, agricultural machinery are considered fundamental for biomass production. The energy analysis in agricultural machinery has been done, but with indicator data from late 1960s. Embodied energy and emissions studies in agricultural machinery should be done, because of bioenergy production system importance in economy, beyond consumption optimization in operations necessary to obtain the product. This study aimed to determine the inventory for materials, embodied energy and greenhouse gases emissions in agricultural machinery. Eight machines were evaluated, so called: coffee harvester, self-propelled sprayer, seeder-fertilizer, combine harvester, tractor 55 kW, tractor 90 kW, tractor 172 kW and tractor 246 kW, on their life cycle. Such were taken from three different sources. The data were collected in a multinational manufacturer, in its units located at Piracicaba and Sorocaba regions, State of São Paulo and Curitiba region, State of Paraná, Brazil. For every harvester, the consumption of the direct input used in the assembly phase, was accounted, and also the consumption of the input used in the maintenance phase. The consumption data of the inputs were processed presenting the materials flows used, which they were multiplied by their embodied energy indices and emissions factor, resulting in the embodied energy and greenhouse gases emissions required by the production system. The results presented higher embodied energy and emissions on life cycle mentioned per manufacturer, for coffee harvester, sprayer, seeder-fertilizer, combine harvester, and on life cycle mentioned per (BRASIL, 2010), for tractors 55 kW, 90 kW, 172 kW and 246 kW, respectively. For environmental assessment on tractors, equations were provided to energy demand and emissions per mass (energy = -0.0057 mass + 129.2669), (emissions = -0.0003 mass + 5.9845) and per engine power (energy = -14.7672 engine power + 6,507.9639), (emissions = -0.6861 engine power + 299.1242).
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Emissão de CO2 da madeira serrada da Amazônia: o caso da exploração convencional. / CO2 of Amazon lumber: the case of conventional logging.Campos, Érica Ferraz de 24 May 2012 (has links)
Informações ambientais de materiais e produtos são essenciais para a gestão de sustentabilidade no setor de construção. Em função das mudanças climáticas, o fator de emissão de dióxido de carbono (CO2) de produtos torna-se relevante para inventariar projetos e edificações, e pautar a decisão de profissionais e consumidores. Com base na metodologia de Análise de Fluxo do Material, a presente pesquisa objetivou quantificar o fator de emissão de CO2 da madeira serrada da Amazônia originária de exploração convencional. O recorte abrangeu a extração de toras da floresta, transporte de toras até serraria, processamento primário e transporte de madeira serrada ao mercado consumidor. Foram consideradas para o cálculo as emissões advindas de resíduos de biomassa e consumo de energia fóssil. Os resultados são apresentados em faixas de valores mínimos a máximos, para cada etapa produtiva, com o objetivo de incorporar incertezas e variações relativas às características do ambiente florestal e procedimentos da atividade madeireira. A quantificação foi principalmente baseada em dados de literatura; entrevistas e questionários com madeireiras da região foram utilizados para determinar o consumo de energia no processo. Entre 200 t/ha e 425 t/ha de biomassa seca acima do solo compõem a floresta Amazônica, de acordo com as características regionais. Essa biomassa estoca de 98 tC/ha a 208 tC/ha. Na exploração convencional são extraídas de 3 a 9 árvores por hectare, estimadas entre 4% e 14% da biomassa. Durante a extração, de 7% a 33% da biomassa florestal é danificada para abertura de trilhas, derrubada de árvores comerciais e arraste de toras. A biomassa destruída na extração é geralmente abandonada na floresta, onde se decompõe, gerando emissões. Nas serrarias, devido ao baixo aproveitamento, pelo menos 54% da biomassa das toras é transformada em resíduos, que são queimados ou degradam, outra fonte de CO2. Somando floresta e serraria, são produzidos de 5,0 t/t a 8,5 t/t na relação entre resíduos e madeira serrada. As emissões relativas aos resíduos, por unidade de tora processada, são estimados de 3,4 tCO2/t a 9,7 tCO2/t. As emissões por consumo de energia para extração, transporte de toras e processamento contribuem com 0,02 tCO2/t a 0,12 tCO2/t de tora processada. Ao final do processo produtivo, estimou-se a faixa de variação das emissões de 7,5 tCO2/t a 28,4 tCO2/t de madeira serrada, equivalentes a 5,2 tCO2/m³ e 19,6 tCO2/m³. Outra etapa considerada foi o transporte do produto entre serraria e mercado consumidor, que incrementa em 0,03 tCO2/t a 0,12 tCO2/t de madeira serrada, se admitidos 1.956 km, estimativa de distância média percorrida legalmente com a madeira amazônica no Brasil. O fator de emissão de CO2 da madeira serrada da Amazônia pode fundamentar políticas públicas para sua mitigação na atividade madeireira, bem como pautar iniciativas do setor público, construção civil e consumidores. A destruição da floresta foi identificada como a principal influência no fator de emissão de CO2 da madeira serrada. Para mitigação do CO2 nessa etapa, o modelo convencional de exploração precisaria ser revisto, o que conjuntamente promoveria a conservação da floresta. O aproveitamento de resíduos de floresta e serraria configura outra oportunidade relevante para a redução de impacto ambiental do produto. A parcela de contribuição da produção de madeira serrada Amazônica sobre as emissões brasileiras de 2005 foi estimada entre 3,5% e 13,1%. Para a proposição de ações eficazes, o impacto de diversos modelos de exploração madeireira precisa ser medido e sua análise ser aprofundada, para as diferentes regiões da floresta Amazônica. / Environmental information of materials and products are essential for sustainability management in construction. Due to climate change, CO2 emission of products are relevant to inventory buildings and projects and to guide professionals\' and consumers decisions. Based on Material Flow Analysis, this research aim to quantify CO2 emission factor of Amazon lumber from conventional logging. The study included stages of logging, transportation of logs, sawing and lumber transportation. CO2 emissions from residues of biomass and energy consumption were considered in quantification. The results are presented in ranges for each stage of chain production, in order to incorporate uncertainties and variations of forest characteristics and procedures. Quantification was mainly based on literature; interviews with logging companies were used to define energy consumption. Amazon rainforest is composed of 200 t/ha to 425 t/ha of above ground dry biomass, which depends on forest region, and stocks between 98 tC/ha and 208 tC/ha. In conventional logging 3-9 trees per hectare are usually extracted, estimated as 4% to 14% of forest biomass. During logging, from 7% to 33% of the forest biomass is damaged to open trails, fall trees and remove commercial logs. The damaged biomass is usually left at forest, where it decomposes, causing CO2 emissions. In sawmills, at least 54% of the biomass is transformed into residues, which are burned or degraded, other CO2 source. Combining forest and sawmill residues, from 5.0 t residues/ t lumber to 8.5 t/t are generated. The CO2 emissions from residues of biomass, per unit of processed roundwood, are estimated from 3.4 tCO2/t to 9.7 tCO2/t. Energy consumed in extraction, logs transportation and sawing contribute with 0.02 tCO2/t to 0.12 tCO2/t of processed roundwood. At the end of the production, emissions were estimated from 7.5 tCO2/t to 28.4 tCO2/t of lumber, equivalent to 5.2 tCO2/m³ to 19.6 tCO2/m³. Lumber transportation from sawmills to consumer market is another stage that increases emissions from 0.03 tCO2/t to 0.12 tCO2/t of lumber, if admitted 1,956 km, the estimated average distance for legal Amazon lumber transportation in Brazil. CO2 emission factor of Amazon lumber may contribute to mitigation policies in wood sector, as well as guide initiatives of public sector, construction sector and consumers. The destruction of forest biomass was identified as the main influence on CO2 emission factor of Amazon lumber. To minimize CO2 emissions the conventional model of exploitation need to be revised, what would also promote Amazon rainforest conservation. The use of residues from forest and sawmills is another relevant opportunity to reduce environmental impact of lumber. The contribution of Amazon lumber in Brazilian CO2 emissions, based on 2005 data, was estimated from 3.5% to 13.1%. To propose effective actions, the impact of logging in different models of exploitation must be measured in different regions of Amazon forest.
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Metabolismo de um município brasileiro de pequeno porte : o caso de Feliz, RS / Metabolism of a small Brazilian municipality : Feliz, RS, case studyKuhn, Eugenia Aumond January 2014 (has links)
Estudos relacionados ao consumo de recursos e à emissão de resíduos na escala territorial local se originaram nas pioneiras pesquisas associadas ao conceito de metabolismo urbano. Nos últimos 15 anos, observa-se um crescimento do número de estudos aplicados a cidades, municípios ou regiões metropolitanas. A Análise dos Fluxos de Materiais - AFM (Material Flow Analysis) vem se consolidando como a abordagem metodológica predominante para esse tipo de investigação, a qual objetiva prover informações sobre fluxos de materiais e de energia, usualmente em unidades de massa, entrando e deixando uma sociedade. No entanto, todos os casos estudados na literatura prévia correspondem a capitais nacionais ou a municípios com centralidade econômica e de gestão do território na região as quais pertencem. Adicionalmente, não há estudos desenvolvidos no Brasil. Em face dessas lacunas, o objetivo principal deste trabalho é a caracterização dos fluxos de materiais associados ao metabolismo de um município brasileiro de pequeno porte (MBPP). Para tanto se adotou como estudo de caso o município de Feliz-RS. Como objetivos intermediários da pesquisa estabeleceram-se: a) Identificação dos métodos existentes para caracterização de fluxos de materiais na escala local e análise das possibilidades de aplicação no contexto dos MBPP; b) Desenvolvimento de um detalhamento metodológico da AFM, para a caracterização dos fluxos de materiais de MBPP; c) Análise das limitações e oportunidades para uso da AFM, na avaliação de sustentabilidade ambiental de municípios. Como resultados, avalia-se que o detalhamento metodológico desenvolvido é funcional e replicável para municípios brasileiros com o mesmo perfil, além de fornecer informações bastante detalhadas acerca dos fluxos ocorrentes no município adotado como caso. Assim, é possível realizar análises com diferentes níveis de desagregação. Quanto aos fluxos de materiais de Feliz, encontrou-se que o consumo doméstico de materiais per capita (DMC/ per capita) do município é alto, se comparado àqueles já caracterizados na literatura. Essa constatação corrobora com a proposição de que municípios com produção primária e secundária tendem a demandar, proporcionalmente, mais recursos do que aqueles que são consumidores finais. Quanto ao uso da AFM, na avaliação de sustentabilidade ambiental, verifica-se um alto potencial, com vantagens, em relação a outros métodos correntemente adotados. Entretanto, essas oportunidades ainda são pouco exploradas no contexto internacional e ignoradas no Brasil, ao se analisar a literatura existente. / Studies related to resources consumption and wastes emissions in a local territorial scale were originated from pioneering researches related to the urban metabolism concept. Over the past 15 years, there was a growth in the number of such studies applied to cities, municipalities and metropolitan areas. At the same time, Material Flow Analysis - MFA was consolidated as the predominant methodological approach for this type of research. However, it must be pointed out that all studied cases have been related to national capitals or counties, with economics centrality and land management in their own area. Besides, no studies of this nature were found as being developed in Brazil. Thus, the main goal of the research presented in this paper was to characterize material flows associated with the metabolism of a small Brazilian municipality and for this purpose the municipality of Feliz was adopted as a case study. Three intermediate objectives were established: a) To identify existing methods for material flows characterization on the local scale and to analyse the possibilities of applying them in the context of small Brazilian municipalities; b) to develop a MFA methodological detailing for the characterization of material flows of small Brazilian municipalities; c) to analyse constraints and opportunities for the use of MFA in the assessment of municipalities environmental sustainability. As results, it is considered that the methodological detailing developed raises the possibility of replicating the procedures applied in Feliz to other Brazilian municipalities, being this research a first and referential step in this direction. Besides, it provides very detailed information on flows occurring in the municipality adopted as the case study. Thus, it is possible ti further develop of analyses considering different levels of disaggregation. Concerning the material flows associated with the metabolism of Feliz, it was found that the studied municipality presents a DMC per capita comparable or superior to that of larger municipalities already analyzed by previous researches. This finding corroborates the hypothesis that municipalities with primary and secondary production tend to demand proportionately more resources than those who are the final consumers. Regarding the use of the MFA in the assessment of municipalities environmental sustainability, it was verified that it presents a high potential, with advantages over other methods currently adopted. However, when analyzing the existing literature it was noticed that these opportunities are still little explored in the international context and ignored in Brazil.
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Optimalizace materiálového toku ve vybraném podniku / Optimization of Material Flow in a Selected CompanySedláček, Petr January 2016 (has links)
The focus of this thesis is the optimization of material flow by changing the layout of racking systems and production lines. The theoretical part describes lean management and its use in internal logistics. Gained knowledge along with practical operating experience leads to the elaboration of analytical and design part, which provides a new solution to the presented problem and related savings in warehouse machine equipment and its staff.
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Investigation and modelling of friction stir welded copper canistersKällgren, Therese January 2010 (has links)
This work has been focused on characterisation of FSW joints, and modelling of the process, both analytically and numerically. The Swedish model for final deposit of nuclear fuel waste is based on copper canisters as a corrosion barrier with an inner pressure holding insert of cast iron. Friction Stir Welding (FSW) is the method to seal the copper canister, a technique invented by The Welding Institute (TWI). The first simulations were based on Rosenthal’s analytical medium plate model. The model is simple to use, but has limitations. Finite element models (FEM) were developed, initially with a two-dimensional geometry. Due to the requirements of describing both the heat flow and the tool movement, three-dimensional models were developed. These models take into account heat transfer, material flow, and continuum mechanics. The geometries of the models are based on the simulation experiments carried out at TWI and at Swedish Nuclear Fuel Waste and Management Co (SKB). Temperature distribution, material flow and their effects on the thermal expansion were predicted for a full-scale canister and lid. The steady state solutions have been compared with temperature measurements, showing good agreement. In order to understand the material flow during welding a marker technique is used, which involves inserting dissimilar material into the weld zone before joining. Different materials are tested showing that brass rods are the most suitable material in these welds. After welding, the weld line is sliced, etched and examined by optical microscope. To understand the material flow further, and in the future predict the flow, a FEM is developed. This model and the etched samples are compared showing similar features. Furthermore, by using this model the area that is recrystallised can be predicted. The predicted area and the grain size and hardness profile agree well. Microstructure and hardness profiles have been investigated by optical microscopy, Scanning Electron Microscopy (SEM), Electron Back Scatter Diffraction (EBSD) and Rockwell hardness measurements. EBSD visualisation has been used to determine the grain size distribution and the appearance of twins and misorientation within grains. The orientation maps show a fine uniform equiaxed grain structure. The root of the weld exhibits the smallest grains and many annealing twins. The appearance of the nugget and the grain size depends on the position of the weld. A large difference can be seen both in hardness and grain size between the start of the weld and when the steady state is reached. / QC20100719
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