940 resultados para life cycle assessment bio-fuel cell biomass waste LCA biowaste valorization


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Työssä tarkasteltiin sähkö- ja lämpöenergian tuotantomenetelmien ympäristöllistä kilpailukykyä osana yhdyskunnan energiajärjestelmää. Sähkö- lämpöenergian tuotantomenetelmiä vertailtiin keskenään aiheutuvien kasvihuonekaasupäästöjen perusteella. Tarkastelu toteutettiin elinkaariarviointimenetelmällä. Työssä mallinnettiin pääasiassa uusiutuviin energialähteisiin perustuvia menetelmiä yhdyskunnan vuotuisen sähkö- ja lämpöenergiantarpeen täyttämiseksi. Elinkaariarviointimallin avulla vertailtiin keskenään aurinko- ja tuulisähköpainotteista ja CHP-painotteista energiajärjestelmää. Lisäksi työssä arvioitiin aurinko- ja tuulisähköntuotantoa sekä CHP-tuotantoa nettoenergianäkökulmasta. Työn tulosten pohjalta voidaan olettaa, että kokonaisvaltaisesti paras energianhankintavaihtoehto on usean eri sähkö- ja lämpöenergiantuotantomenetelmän yhdistelmä. Alhainen päästötaso tietyssä kategoriassa on yhdentekevää, jos energiaa ei ole saatavissa silloin, kun sitä tarvitaan. Lisäksi on tärkeää huomata, että uusiutuvien energialähteiden hyödynnettävyys riippuu vahvasti alueellisista erityispiirteistä, kuten aurinko- ja tuuliolosuhteista. Tästä johtuen kestävän energiajärjestelmän suunnittelussa alueellisten ominaisuuksien huomiointi on tärkeää. Mikä tietyllä alueella osoittautuu parhaimmaksi ratkaisuksi, ei välttämättä ole sitä toisenlaisessa ympäristössä.

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This study is a qualitative action research by its nature with elements of personal design in the form of a tangible model implementation framework construction. Utilized empirical data has been gathered via two questionnaires in relation to the arranged four workshop events with twelve individual participants. Five of them represented maintenance customers, three maintenance service providers and four equipment providers respectively. Further, there are two main research objectives in proportion to the two complementary focusing areas of this thesis. Firstly, the value-based life-cycle model, which first version has already been developed prior to this thesis, requires updating in order to increase its real-life applicability as an inter-firm decision-making tool in industrial maintenance. This first research objective is fulfilled by improving appearance, intelligibility and usability of the above-mentioned model. In addition, certain new features are also added. The workshop participants from the collaborating companies were reasonably pleased with made changes, although further attention will be required in future on the model’s intelligibility in particular as main results, charts and values were all reckoned as slightly hard to understand. Moreover, upgraded model’s appearance and added new features satisfied them the most. Secondly and more importantly, the premises of the model’s possible inter-firm implementation process need to be considered. This second research objective is delivered in two consecutive steps. At first, a bipartite open-books supported implementation framework is created and its different characteristics discussed in theory. Afterwards, the prerequisites and the pitfalls of increasing inter-organizational information transparency are studied in empirical context. One of the main findings was that the organizations are not yet prepared for network-wide information disclosure as dyadic collaboration was favored instead. However, they would be willing to share information bilaterally at least. Another major result was that the present state of companies’ cost accounting systems will definitely need implementation-wise enhancing in future since accurate and sufficiently detailed maintenance data is not available. Further, it will also be crucial to create supporting and mutually agreed network infrastructure. There are hardly any collaborative models, methods or tools currently in usage. Lastly, the essential questions about mutual trust and predominant purchasing strategies are cooperation-wise important. If inter-organizational activities are expanded, a more relational approach should be favored in this regard. Mutual trust was also recognized as a significant cooperation factor, but it is hard to measure in reality.

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Toxoplasma gondii and Trypanosoma cruzi are intracellular parasites which, as part of their life cycle, induce a potent cell-mediated immunity (CMI) maintained by Th1 lymphocytes and IFN-g. In both cases, induction of a strong CMI is thought to protect the host against rapid parasite multiplication and consequent pathology and lethality during the acute phase of infection. However, the parasitic infection is not eliminated by the immune system and the vertebrate host serves as a parasite reservoir. In contrast, Leishmania sp, which is a slow growing parasite, appears to evade induction of CMI during early stages of infection as a strategy for surviving in a hostile environment (i.e., inside the macrophages which are their obligatory niche in the vertebrate host). Recent reports show that the initiation of IL-12 synthesis by macrophages during these parasitic infections is a key event in regulating CMI and disease outcome. The studies reviewed here indicate that activation/inhibition of distinct signaling pathways and certain macrophage functions by intracellular protozoa are important events in inducing/modulating the immune response of their vertebrate hosts, allowing parasite and host survival and therefore maintaining parasite life cycles.

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Sm14 is a 14-kDa vaccine candidate antigen from Schistosoma mansoni that seems to be involved in cytoplasmic trafficking of fatty acids. Although schistosomes have a high requirement for lipids, they are not able to synthesize fatty acids and sterols de novo. Thus, they must acquire host lipids. In order to determine whether Sm14 is present in different stages of the life cycle of the parasite, we performed RT-PCR. Sm14 mRNA was identified in all stages of the life cycle studied, mainly schistosomulum, adult worm and egg. Additionally, we used a rabbit anti-Sm14 polyclonal antibody in an indirect immunofluorescence assay to localize Sm14 in adult worm sections. The basal lamella of the tegument and the gut epithelium were strongly labeled. These tissues have a high flow of and demand for lipids, a finding that supports the putative role of Sm14 as an intracellular transporter of fatty acids from host cells.

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Cement industry significantly associated with high greenhouse gas (GHG) emissions. Considering the environmental impact, particularly global warming potential, it is important to reduce these emissions to air. The aim of the study is to investigate the mitigation possibility of GHG emissions in Ethiopian cement industry. Life cycle assessment (LCA) method used to identify and quantify GHG emissions during one ton of ordinary portland cement (OPC) production. Three mitigation scenarios: alternative fuel use, clinker substitution and thermal energy efficiency were applied on a representative gate-to-gate flow model developed with GaBi 6 software. The results of the study indicate that clinker substitution and alternative fuel use play a great role for GHG emissions mitigation with affordable cost. Applying most energy efficient kiln technology, which in turn reduces the amount of thermal energy use, has the least GHG emissions reduction intensity and high implementation cost comparing to the other scenarios. It was found that the cumulative GHG emissions mitigation potential along with other selected mitigation scenarios can be at least 48.9% per ton of cement production.

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Laser additive manufacturing (LAM), known also as 3D printing, is a powder bed fusion (PBF) type of additive manufacturing (AM) technology used to manufacture metal parts layer by layer by assist of laser beam. The development of the technology from building just prototype parts to functional parts is due to design flexibility. And also possibility to manufacture tailored and optimised components in terms of performance and strength to weight ratio of final parts. The study of energy and raw material consumption in LAM is essential as it might facilitate the adoption and usage of the technique in manufacturing industries. The objective this thesis was find the impact of LAM on environmental and economic aspects and to conduct life cycle inventory of CNC machining and LAM in terms of energy and raw material consumption at production phases. Literature overview in this thesis include sustainability issues in manufacturing industries with focus on environmental and economic aspects. Also life cycle assessment and its applicability in manufacturing industry were studied. UPLCI-CO2PE! Initiative was identified as mostly applied exiting methodology to conduct LCI analysis in discrete manufacturing process like LAM. Many of the reviewed literature had focused to PBF of polymeric material and only few had considered metallic materials. The studies that had included metallic materials had only measured input and output energy or materials of the process and compared to different AM systems without comparing to any competitive process. Neither did any include effect of process variation when building metallic parts with LAM. Experimental testing were carried out to make dissimilar samples with CNC machining and LAM in this thesis. Test samples were designed to include part complexity and weight reductions. PUMA 2500Y lathe machine was used in the CNC machining whereas a modified research machine representing EOSINT M-series was used for the LAM. The raw material used for making the test pieces were stainless steel 316L bar (CNC machined parts) and stainless steel 316L powder (LAM built parts). An analysis of power, time, and the energy consumed in each of the manufacturing processes on production phase showed that LAM utilises more energy than CNC machining. The high energy consumption was as result of duration of production. Energy consumption profiles in CNC machining showed fluctuations with high and low power ranges. LAM energy usage within specific mode (standby, heating, process, sawing) remained relatively constant through the production. CNC machining was limited in terms of manufacturing freedom as it was not possible to manufacture all the designed sample by machining. And the one which was possible was aided with large amount of material removed as waste. Planning phase in LAM was shorter than in CNC machining as the latter required many preparation steps. Specific energy consumption (SEC) were estimated in LAM based on the practical results and assumed platform utilisation. The estimated platform utilisation showed SEC could reduce when more parts were placed in one build than it was in with the empirical results in this thesis (six parts).

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Yritysten liiketoimintamallit ovat jatkuvan kehityksen kohteena. Viimeisinä vuosina valmistavien yhtiöiden kiinnostus huolehtia asiakkaistaan koko tuotteen elinkaaren aikana ja tarjota erilaisia palveluita asiakkailleen on kasvanut. Tämän palvelujen laajentumisen myötä myös vaateet yrityksen omaa toimittajakenttää kohtaan ovat muuttuneet. Yritykset eivät kykene tuottamaan kaikkia tuotteistamiaan palveluja itse, jolloin yrityksen toimittajakenttä ja sen kyvykkyydet tuottaa tarvittavia palveluita ovat avainasemassa yrityksen menestystekijänä. Tämän työn teoriaosuudessa on esitelty toimittajakentän hallinnan perusteorioita. Kirjallisuus osuuden lisäksi työssä on hyödynnetty toimintatutkimusta kohdeyrityksessä. Tässä diplomityössä on tutkittu mahdollisia keinoja kehittää organisaation omaa toimintaa ja sekä yrityksen toimittajakenttää niin, että se tukee liiketoimintamallin kehitystä koneenrakennusyrityksestä kohti elinkaariliiketoimintaa. Työssä esitetyt keinot voidaan ottaa käyttöön, joko yksitellen tai kokonaisuutena.

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The goal of the thesis was to investigate how much after-sales profits a crane sale generates over the life cycle of the crane and the effects of these after-sales profits on the overall profitability of the crane. The thesis utilizes theories about life cycle costing from an equipment and service supplier’s point of view. However, instead of costs, the thesis is focused on the life cycle after-sales profits from maintenance services and spare parts provided for the sold crane. The case study approach was chosen and a total of five cranes from three different segments were investigated. An eight-step life cycle profit calculation model was developed in order to analyze the chosen cases’ life cycle profits systematically. The results of the investigation suggest that the life cycle after-sales profits are significant in value. In the case analyses they accounted for between 20% and 44% of the overall life cycle profits of the case cranes. The after-sales profits should be taken into account already in the pricing when offering a crane to a customer.

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Protein energy malnutrition (PEM) is a syndrome that often results in immunodeficiency coupled with pancytopenia. Hemopoietic tissue requires a high nutrient supply and the proliferation, differentiation and maturation of cells occur in a constant and balanced manner, sensitive to the demands of specific cell lineages and dependent on the stem cell population. In the present study, we evaluated the effect of PEM on some aspects of hemopoiesis, analyzing the cell cycle of bone marrow cells and the percentage of progenitor cells in the bone marrow. Two-month-old male Swiss mice (N = 7-9 per group) were submitted to PEM with a low-protein diet (4%) or were fed a control diet (20% protein) ad libitum. When the experimental group had lost about 20% of their original body weight after 14 days, we collected blood and bone marrow cells to determine the percentage of progenitor cells and the number of cells in each phase of the cell cycle. Animals of both groups were stimulated with 5-fluorouracil. Blood analysis, bone marrow cell composition and cell cycle evaluation was performed after 10 days. Malnourished animals presented anemia, reticulocytopenia and leukopenia. Their bone marrow was hypocellular and depleted of progenitor cells. Malnourished animals also presented more cells than normal in phases G0 and G1 of the cell cycle. Thus, we conclude that PEM leads to the depletion of progenitor hemopoietic populations and changes in cellular development. We suggest that these changes are some of the primary causes of pancytopenia in cases of PEM.

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Industrial production of pulp and paper is an intensive consumer of energy, natural resources, and chemicals that result in a big carbon footprint of the final product. At present companies and industries aspire to calculate their gas emissions into the atmosphere in order to afterwards reduce atmospheric contamination. One of the approaches allowing to increase carbon burden from the pulp and paper manufacture is paper recycling. The general purpose of the current paper is to establish methods of quantifying and minimizing the carbon footprint of paper. The first target of this research is to derive a mathematical relationship between virgin fibre requirements with respect to the amount of recycled paper used in the pulp. One more purpose is to establish a model to be used to clarify the contribution of recycling and transportation to decreasing carbon dioxide emissions. For this study sensitivity analysis is used to investigate the robustness of obtained results. The results of the present study show that an increasing of recycling rate does not always lead to minimizing the carbon footprint. Additionally, we derived that transportation of waste paper throughout distances longer than 5800 km has no sense because the use of that paper will only increase carbon dioxide emissions and it is better to reject recycling at all. Finally, we designed the model for organization of a new supply chain of paper product to a customer. The models were implemented as reusable MATLAB frameworks.

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The focus of the research is on the derivation of the valid and reliable performance results regarding establishment and launching of the new full-scale industrial facility, considering the overall current conditions for the project realization in and out of Russia. The study demonstrates the process of the new facility concept development, with following perfor-mance calculation, comparative analyzes conduction, life-cycle simulations, performance indicators derivation and project`s sustainability evaluation. To unite and process the entire input parameters complexity, regards the interlacing between the project`s internal technical and commercial sides on the one hand, and consider all the specifics of the Russian conditions for doing business on the other hand, was developed the unique model for the project`s performance calculation, simulations and results representation. The complete research incorporates all corresponding data to substantiate the assigned facility`s design, sizing and output capacity for high quality and cost efficient ferrous pipe-line accessories manufacturing, as well as, demonstrates that this project could be suc-cessfully realized in current conditions in Russia and highlights the room for significant performance and sustainability improvements based on the indexes of the derived KPIs.

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Climatic impacts of energy-peat extraction are of increasing concern due to EU emissions trading requirements. A new excavation-drier peat extraction method has been developed to reduce the climatic impact and increase the efficiency of peat extraction. To quantify and compare the soil GHG fluxes of the excavation drier and the traditional milling methods, as well as the areas from which the energy peat is planned to be extracted in the future (extraction reserve area types), soil CO2, CH4 and N2O fluxes were measured during 2006–2007 at three sites in Finland. Within each site, fluxes were measured from drained extraction reserve areas, extraction fields and stockpiles of both methods and additionally from the biomass driers of the excavation-drier method. The Life Cycle Assessment (LCA), described at a principal level in ISO Standards 14040:2006 and 14044:2006, was used to assess the long-term (100 years) climatic impact from peatland utilisation with respect to land use and energy production chains where utilisation of coal was replaced with peat. Coal was used as a reference since in many cases peat and coal can replace each other in same power plants. According to this study, the peat extraction method used was of lesser significance than the extraction reserve area type in regards to the climatic impact. However, the excavation-drier method seems to cause a slightly reduced climatic impact as compared with the prevailing milling method.

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The importance of industrial maintenance has been emphasized during the last decades; it is no longer a mere cost item, but one of the mainstays of business. Market conditions have worsened lately, investments in production assets have decreased, and at the same time competition has changed from taking place between companies to competition between networks. Companies have focused on their core functions and outsourced support services, like maintenance, above all to decrease costs. This new phenomenon has led to increasing formation of business networks. As a result, a growing need for new kinds of tools for managing these networks effectively has arisen. Maintenance costs are usually a notable part of the life-cycle costs of an item, and it is important to be able to plan the future maintenance operations for the strategic period of the company or for the whole life-cycle period of the item. This thesis introduces an itemlevel life-cycle model (LCM) for industrial maintenance networks. The term item is used as a common definition for a part, a component, a piece of equipment etc. The constructed LCM is a working tool for a maintenance network (consisting of customer companies that buy maintenance services and various supplier companies). Each network member is able to input their own cost and profit data related to the maintenance services of one item. As a result, the model calculates the net present values of maintenance costs and profits and presents them from the points of view of all the network members. The thesis indicates that previous LCMs for calculating maintenance costs have often been very case-specific, suitable only for the item in question, and they have also been constructed for the needs of a single company, without the network perspective. The developed LCM is a proper tool for the decision making of maintenance services in the network environment; it enables analysing the past and making scenarios for the future, and offers choices between alternative maintenance operations. The LCM is also suitable for small companies in building active networks to offer outsourcing services for large companies. The research introduces also a five-step constructing process for designing a life-cycle costing model in the network environment. This five-step designing process defines model components and structure throughout the iteration and exploitation of user feedback. The same method can be followed to develop other models. The thesis contributes to the literature of value and value elements of maintenance services. It examines the value of maintenance services from the perspective of different maintenance network members and presents established value element lists for the customer and the service provider. These value element lists enable making value visible in the maintenance operations of a networked business. The LCM added with value thinking promotes the notion of maintenance from a “cost maker” towards a “value creator”.

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Työn tavoitteena oli tehdä elinkaariarviointi (LCA) prosessiteollisuuden sekoittimelle Helmix HF-80 ja analysoida LCA-tulokset, vaikutus ilmaston lämpenemisen potentiaalin (GWP) suhteen, sekä tutkia GWP-vaikutuksen pienentämisen mahdollisuuksia. Tutkittavan sekoittimen mahdolliset käyttökohteet ovat sellu- ja paperiteollisuus, raskaiden jätenesteiden käsittely, sekä muut teollisuusalueet, joissa käytetään tämän tyyppisiä laitteita. Työssä on muun muassa käsitelty sekoitusprosessit, sekoituslaitteiden tyypit, niiden rakenteiden ominaisuudet, käyttötarkoitus, toimintaperiaatteet, sekä sellu- ja paperi-teollisuudessa käytettävien sekoittimien yleiskatsaus. Työssä on myös kuvattu elinkaariarviointi (LCA) -menetelmä ja sen käyttötarkoitus. Tärkeimmistä tuloksista voi mainita sen, että sekoittimen (ilman säiliötä, sähkömoottoria ja vaihteistoa) kokoelinkaaren ilmastonlämpenemisen potentiaali (GWP) on noin 750 000 kg CO2-Equiv. Sekoittimen tuotanto- ja kierrätysaikana syntyy vain 1200 kg CO2-Equiv. ja suurin osa 748 000 kg CO2-Equiv. johtuu sähköenergian kulutuksesta käytön aikana. Käyttöajan vaikutusta voisi pienentää arvoksi 0 kg CO2-Equiv. käyttämällä pelkästään uusiutuvaa energiaa. Jos tuotantoaikana käytetty energia myös korvataan uusiutuvalla energialla, niin GWP-arvo koko elinkaaren aikana laskee arvoon 1006 kg CO2eqv., mikä on vain 0,13 % saaduista tuloksista. Suurin osa tästä arvosta liittyy sekoittimen materiaalin, tässä tapauksessa ruostumattoman teräksen tuotantoon.