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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Novel sustainable solvents for bioprocessing applications

Kassner, Michelle Kimberly 17 November 2008 (has links)
Bioprocessing applications are gaining importance in the traditional chemical industries. With environmental, political, and economical concerns growing, research efforts have recently focused on the substitution of petroleum-derived transportation fuels and materials. As possible products and feedstocks are being investigated, it is important to ensure the new processes are also sustainable. There are several aspects to developing sustainable processes: minimize waste, use environmentally-benign chemicals, find renewable feedstocks, and limit the number of processing steps. This thesis examines ways to enhance the sustainability of bioprocesses. Novel, alternative solvent systems are studied and applied to a variety of bioprocesses. Downstream processing steps and waste can be minimized by designing systems that combine reactions and separations into one process unit. This is accomplished by designing new reactor systems and by replacing currently used solvents. Additional studies, involving analytical techniques that reduce the use of organic solvents, are tested and applied to industrial problems. Finally, new solvent systems are examined for potential processes using renewable carbohydrate feedstock.
2

Proposta de uma tecnologia ambientalmente sustentável para o tratamento de efluentes de indústrias galvânicas contendo Cr(VI)

Machado, Tiele Caprioli January 2015 (has links)
O cromo hexavalente – Cr(VI) – presente nos efluentes das indústrias galvânicas, entre outras, é tóxico para maioria dos micro-organismos e potencialmente danoso para a saúde humana. No presente trabalho se estuda a redução de Cr(VI) pelos processos fotoquímicos com álcoois e fotocatálise heterogênea, primeiramente em um reator batelada, com objetivo de obter o melhor processo para aplicação industrial. Na sequência, foram realizados experimentos com efluente industrial, contendo Cr(VI), proveniente de uma indústria galvânica. Após, foram projetados e construídos dois reatores contínuos, o reator em forma de espiral e o reator tubular (radiação artificial e luz solar), com intuito de viabilizar a aplicação industrial do melhor processo de redução de Cr(VI). As reações de redução fotocatalítica de Cr(VI), sob radiação UV, alcançaram reduções totais de Cr(VI) de 66,5% e 56,7% para os catalisadores TiO2 e ZnO, respectivamente, indicando que o catalisador TiO2 foi mais eficiente que o catalisador ZnO. As reações de redução fotoquímica de Cr(VI) com etanol apresentaram altos valores de redução total de Cr(VI), sendo que as reações sob radiação UV (96,1%) foram mais eficientes que as reações sob radiação visível (48,1%). Na redução fotocatalítica de Cr(VI) com TiO2, na presença de etanol, sob radiação UV, foi observada uma redução de Cr(VI) de 92,9% maior do que a redução obtida nas reações fotocatalíticas com TiO2 sob radiação UV (66,5%), evidenciando o efeito sinérgico entre a oxidação do etanol e a redução do Cr(VI). Quando usados com efluente industrial, estes processos mostraram-se eficientes e obtiveram altos valores de redução total de Cr(VI), possibilitando o uso destes tratamentos para remoção de Cr(VI) presente em efluentes de indústrias galvânicas. Entretanto, dentre estes processos estudados, o mais indicado para aplicação industrial foi a fotoquímica com etanol sob radiação UV, pois dispensa o uso de processos de separação do catalisador e apresenta menores custos com reagentes, sendo o etanol de baixo custo, não tóxico e de fácil aquisição. O reator contínuo espiral, projetado e construído, mostrou-se mais eficiente do que o reator batelada, apresentando uma eficiência fotônica de 2,5% comparada a 1,4% para o reator batelada. Ainda, este reator mostrou-se eficiente quando usado com efluente industrial, apresentando uma redução total de Cr(VI) de 51,8%, em 6 horas de reação, sendo sua configuração considerada suscetível para um scale-up. Assim, um reator tubular (radiação artificial e luz solar) foi projetado e construído em escala semi-piloto. Este reator apresentou uma remediação de Cr(VI), presente no efluente industrial, de 86,7% em 6 horas de reação sob luz solar e mostrou uma eficiência fotônica maior do que o reator contínuo espiral. Ainda, o reator tubular apresentou eficiência fotônica similar quando usado com lâmpadas (5,6%) ou luz solar (5,5%), porém as reações sob luz solar mostraram uma maior redução total de Cr(VI) quando comparadas com as reações sob radiação artificial. Assim, o reator tubular, projetado e construído, mostrou-se eficiente quando aplicado para o tratamento de efluente industrial contendo Cr(VI), pelo processo de redução fotoquímica. Além disso, o uso do reator tubular solar minimiza a quantidade de energia elétrica necessária para a reação, reduzindo não somente os custos do processo, como também se tornando uma tecnologia ambientalmente sustentável. / Hexavalent chromium – Cr(VI) – present in wastewater discharge of galvanic industries is toxic to most microorganisms and potentially harmful to human health. In this work were studied Cr(VI) reduction by heterogeneous photocatalysis and photochemistry with alcohols processes, firstly in a batch reactor, in order to obtain the best process for industrial application. Subsequently, experiments were conducted using real wastewater from an electroplating plant. In order to feasible the industrial application of best Cr(VI) reduction process were designed and built two continuous reactors, the spiral shaped reactor and the tubular reactor (artificial radiation and sunlight). The photocatalytic reduction reaction of Cr(VI) under UV radiation achieved total Cr(VI) reduction of 66.5% and 56.7% for TiO2 and ZnO catalysts, respectively, indicating that the TiO2 catalyst was more efficient than ZnO catalyst. The photochemical reduction reaction of Cr(VI) with ethanol presented high values of total Cr(VI) reduction, and the reactions under UV radiation (96.10%) were more efficient than the reactions under visible radiation (48.1%). In the photocatalytic reduction reaction of Cr(VI) with TiO2 in the presence of ethanol under UV radiation was observed a Cr(VI) reduction of 92.9% greater than the reduction obtained in the photocatalytic reactions with TiO2 under UV radiation (66.5%), demonstrating the synergistic effect between ethanol oxidation and Cr(VI) reduction. When used with real wastewater these processes proved to be efficient and showed high values of total Cr(VI) reduction, enabling the use of these treatments for removal of Cr(VI) present in wastewater discharge of galvanic industries. However, among these processes studied, the most suitable for industrial application appears to be photochemistry with ethanol under UV radiation, because it does not require catalyst separation processes and presents lower reagent costs, since ethanol is inexpensive, non-toxic and easy to purchase. The spiral shaped reactor, which was designed and built, showed more efficient than the batch reactor, presenting a photonic efficiency of 2.5% compared to 1.4% for the batch reactor. Additionally, this reactor was effective when applied to real wastewater, presenting a total Cr(VI) reduction of 51.8% in 6 hours of reaction, and its configuration is suitable for scale up. Thus, a tubular reactor (artificial radiation and sunlight) was designed and built in semi-pilot scale. This reactor presented a Cr(VI) remediation of 86.7% in 6 hours of reaction under sunlight and showed a photonic efficiency higher than spiral shaped reactor. Additionally, the tubular reactor presented similar photonic efficiency when used with either lamps (5.6%) or sunlight (5.5%), however the reactions under sunlight showed a greater total Cr(VI) reduction when compared to the reactions under artificial radiation. Therefore, the tubular reactor, which was designed and built, proved to be efficient when applied to treatment of real wastewater containing Cr(VI) by photochemical reduction process. Furthermore, the use of a solar tubular reactor minimizes the amount of electricity required for the reaction, which not only reduces process costs, but also makes the technology more environmentally sustainable.
3

Proposta de uma tecnologia ambientalmente sustentável para o tratamento de efluentes de indústrias galvânicas contendo Cr(VI)

Machado, Tiele Caprioli January 2015 (has links)
O cromo hexavalente – Cr(VI) – presente nos efluentes das indústrias galvânicas, entre outras, é tóxico para maioria dos micro-organismos e potencialmente danoso para a saúde humana. No presente trabalho se estuda a redução de Cr(VI) pelos processos fotoquímicos com álcoois e fotocatálise heterogênea, primeiramente em um reator batelada, com objetivo de obter o melhor processo para aplicação industrial. Na sequência, foram realizados experimentos com efluente industrial, contendo Cr(VI), proveniente de uma indústria galvânica. Após, foram projetados e construídos dois reatores contínuos, o reator em forma de espiral e o reator tubular (radiação artificial e luz solar), com intuito de viabilizar a aplicação industrial do melhor processo de redução de Cr(VI). As reações de redução fotocatalítica de Cr(VI), sob radiação UV, alcançaram reduções totais de Cr(VI) de 66,5% e 56,7% para os catalisadores TiO2 e ZnO, respectivamente, indicando que o catalisador TiO2 foi mais eficiente que o catalisador ZnO. As reações de redução fotoquímica de Cr(VI) com etanol apresentaram altos valores de redução total de Cr(VI), sendo que as reações sob radiação UV (96,1%) foram mais eficientes que as reações sob radiação visível (48,1%). Na redução fotocatalítica de Cr(VI) com TiO2, na presença de etanol, sob radiação UV, foi observada uma redução de Cr(VI) de 92,9% maior do que a redução obtida nas reações fotocatalíticas com TiO2 sob radiação UV (66,5%), evidenciando o efeito sinérgico entre a oxidação do etanol e a redução do Cr(VI). Quando usados com efluente industrial, estes processos mostraram-se eficientes e obtiveram altos valores de redução total de Cr(VI), possibilitando o uso destes tratamentos para remoção de Cr(VI) presente em efluentes de indústrias galvânicas. Entretanto, dentre estes processos estudados, o mais indicado para aplicação industrial foi a fotoquímica com etanol sob radiação UV, pois dispensa o uso de processos de separação do catalisador e apresenta menores custos com reagentes, sendo o etanol de baixo custo, não tóxico e de fácil aquisição. O reator contínuo espiral, projetado e construído, mostrou-se mais eficiente do que o reator batelada, apresentando uma eficiência fotônica de 2,5% comparada a 1,4% para o reator batelada. Ainda, este reator mostrou-se eficiente quando usado com efluente industrial, apresentando uma redução total de Cr(VI) de 51,8%, em 6 horas de reação, sendo sua configuração considerada suscetível para um scale-up. Assim, um reator tubular (radiação artificial e luz solar) foi projetado e construído em escala semi-piloto. Este reator apresentou uma remediação de Cr(VI), presente no efluente industrial, de 86,7% em 6 horas de reação sob luz solar e mostrou uma eficiência fotônica maior do que o reator contínuo espiral. Ainda, o reator tubular apresentou eficiência fotônica similar quando usado com lâmpadas (5,6%) ou luz solar (5,5%), porém as reações sob luz solar mostraram uma maior redução total de Cr(VI) quando comparadas com as reações sob radiação artificial. Assim, o reator tubular, projetado e construído, mostrou-se eficiente quando aplicado para o tratamento de efluente industrial contendo Cr(VI), pelo processo de redução fotoquímica. Além disso, o uso do reator tubular solar minimiza a quantidade de energia elétrica necessária para a reação, reduzindo não somente os custos do processo, como também se tornando uma tecnologia ambientalmente sustentável. / Hexavalent chromium – Cr(VI) – present in wastewater discharge of galvanic industries is toxic to most microorganisms and potentially harmful to human health. In this work were studied Cr(VI) reduction by heterogeneous photocatalysis and photochemistry with alcohols processes, firstly in a batch reactor, in order to obtain the best process for industrial application. Subsequently, experiments were conducted using real wastewater from an electroplating plant. In order to feasible the industrial application of best Cr(VI) reduction process were designed and built two continuous reactors, the spiral shaped reactor and the tubular reactor (artificial radiation and sunlight). The photocatalytic reduction reaction of Cr(VI) under UV radiation achieved total Cr(VI) reduction of 66.5% and 56.7% for TiO2 and ZnO catalysts, respectively, indicating that the TiO2 catalyst was more efficient than ZnO catalyst. The photochemical reduction reaction of Cr(VI) with ethanol presented high values of total Cr(VI) reduction, and the reactions under UV radiation (96.10%) were more efficient than the reactions under visible radiation (48.1%). In the photocatalytic reduction reaction of Cr(VI) with TiO2 in the presence of ethanol under UV radiation was observed a Cr(VI) reduction of 92.9% greater than the reduction obtained in the photocatalytic reactions with TiO2 under UV radiation (66.5%), demonstrating the synergistic effect between ethanol oxidation and Cr(VI) reduction. When used with real wastewater these processes proved to be efficient and showed high values of total Cr(VI) reduction, enabling the use of these treatments for removal of Cr(VI) present in wastewater discharge of galvanic industries. However, among these processes studied, the most suitable for industrial application appears to be photochemistry with ethanol under UV radiation, because it does not require catalyst separation processes and presents lower reagent costs, since ethanol is inexpensive, non-toxic and easy to purchase. The spiral shaped reactor, which was designed and built, showed more efficient than the batch reactor, presenting a photonic efficiency of 2.5% compared to 1.4% for the batch reactor. Additionally, this reactor was effective when applied to real wastewater, presenting a total Cr(VI) reduction of 51.8% in 6 hours of reaction, and its configuration is suitable for scale up. Thus, a tubular reactor (artificial radiation and sunlight) was designed and built in semi-pilot scale. This reactor presented a Cr(VI) remediation of 86.7% in 6 hours of reaction under sunlight and showed a photonic efficiency higher than spiral shaped reactor. Additionally, the tubular reactor presented similar photonic efficiency when used with either lamps (5.6%) or sunlight (5.5%), however the reactions under sunlight showed a greater total Cr(VI) reduction when compared to the reactions under artificial radiation. Therefore, the tubular reactor, which was designed and built, proved to be efficient when applied to treatment of real wastewater containing Cr(VI) by photochemical reduction process. Furthermore, the use of a solar tubular reactor minimizes the amount of electricity required for the reaction, which not only reduces process costs, but also makes the technology more environmentally sustainable.
4

Proposta de uma tecnologia ambientalmente sustentável para o tratamento de efluentes de indústrias galvânicas contendo Cr(VI)

Machado, Tiele Caprioli January 2015 (has links)
O cromo hexavalente – Cr(VI) – presente nos efluentes das indústrias galvânicas, entre outras, é tóxico para maioria dos micro-organismos e potencialmente danoso para a saúde humana. No presente trabalho se estuda a redução de Cr(VI) pelos processos fotoquímicos com álcoois e fotocatálise heterogênea, primeiramente em um reator batelada, com objetivo de obter o melhor processo para aplicação industrial. Na sequência, foram realizados experimentos com efluente industrial, contendo Cr(VI), proveniente de uma indústria galvânica. Após, foram projetados e construídos dois reatores contínuos, o reator em forma de espiral e o reator tubular (radiação artificial e luz solar), com intuito de viabilizar a aplicação industrial do melhor processo de redução de Cr(VI). As reações de redução fotocatalítica de Cr(VI), sob radiação UV, alcançaram reduções totais de Cr(VI) de 66,5% e 56,7% para os catalisadores TiO2 e ZnO, respectivamente, indicando que o catalisador TiO2 foi mais eficiente que o catalisador ZnO. As reações de redução fotoquímica de Cr(VI) com etanol apresentaram altos valores de redução total de Cr(VI), sendo que as reações sob radiação UV (96,1%) foram mais eficientes que as reações sob radiação visível (48,1%). Na redução fotocatalítica de Cr(VI) com TiO2, na presença de etanol, sob radiação UV, foi observada uma redução de Cr(VI) de 92,9% maior do que a redução obtida nas reações fotocatalíticas com TiO2 sob radiação UV (66,5%), evidenciando o efeito sinérgico entre a oxidação do etanol e a redução do Cr(VI). Quando usados com efluente industrial, estes processos mostraram-se eficientes e obtiveram altos valores de redução total de Cr(VI), possibilitando o uso destes tratamentos para remoção de Cr(VI) presente em efluentes de indústrias galvânicas. Entretanto, dentre estes processos estudados, o mais indicado para aplicação industrial foi a fotoquímica com etanol sob radiação UV, pois dispensa o uso de processos de separação do catalisador e apresenta menores custos com reagentes, sendo o etanol de baixo custo, não tóxico e de fácil aquisição. O reator contínuo espiral, projetado e construído, mostrou-se mais eficiente do que o reator batelada, apresentando uma eficiência fotônica de 2,5% comparada a 1,4% para o reator batelada. Ainda, este reator mostrou-se eficiente quando usado com efluente industrial, apresentando uma redução total de Cr(VI) de 51,8%, em 6 horas de reação, sendo sua configuração considerada suscetível para um scale-up. Assim, um reator tubular (radiação artificial e luz solar) foi projetado e construído em escala semi-piloto. Este reator apresentou uma remediação de Cr(VI), presente no efluente industrial, de 86,7% em 6 horas de reação sob luz solar e mostrou uma eficiência fotônica maior do que o reator contínuo espiral. Ainda, o reator tubular apresentou eficiência fotônica similar quando usado com lâmpadas (5,6%) ou luz solar (5,5%), porém as reações sob luz solar mostraram uma maior redução total de Cr(VI) quando comparadas com as reações sob radiação artificial. Assim, o reator tubular, projetado e construído, mostrou-se eficiente quando aplicado para o tratamento de efluente industrial contendo Cr(VI), pelo processo de redução fotoquímica. Além disso, o uso do reator tubular solar minimiza a quantidade de energia elétrica necessária para a reação, reduzindo não somente os custos do processo, como também se tornando uma tecnologia ambientalmente sustentável. / Hexavalent chromium – Cr(VI) – present in wastewater discharge of galvanic industries is toxic to most microorganisms and potentially harmful to human health. In this work were studied Cr(VI) reduction by heterogeneous photocatalysis and photochemistry with alcohols processes, firstly in a batch reactor, in order to obtain the best process for industrial application. Subsequently, experiments were conducted using real wastewater from an electroplating plant. In order to feasible the industrial application of best Cr(VI) reduction process were designed and built two continuous reactors, the spiral shaped reactor and the tubular reactor (artificial radiation and sunlight). The photocatalytic reduction reaction of Cr(VI) under UV radiation achieved total Cr(VI) reduction of 66.5% and 56.7% for TiO2 and ZnO catalysts, respectively, indicating that the TiO2 catalyst was more efficient than ZnO catalyst. The photochemical reduction reaction of Cr(VI) with ethanol presented high values of total Cr(VI) reduction, and the reactions under UV radiation (96.10%) were more efficient than the reactions under visible radiation (48.1%). In the photocatalytic reduction reaction of Cr(VI) with TiO2 in the presence of ethanol under UV radiation was observed a Cr(VI) reduction of 92.9% greater than the reduction obtained in the photocatalytic reactions with TiO2 under UV radiation (66.5%), demonstrating the synergistic effect between ethanol oxidation and Cr(VI) reduction. When used with real wastewater these processes proved to be efficient and showed high values of total Cr(VI) reduction, enabling the use of these treatments for removal of Cr(VI) present in wastewater discharge of galvanic industries. However, among these processes studied, the most suitable for industrial application appears to be photochemistry with ethanol under UV radiation, because it does not require catalyst separation processes and presents lower reagent costs, since ethanol is inexpensive, non-toxic and easy to purchase. The spiral shaped reactor, which was designed and built, showed more efficient than the batch reactor, presenting a photonic efficiency of 2.5% compared to 1.4% for the batch reactor. Additionally, this reactor was effective when applied to real wastewater, presenting a total Cr(VI) reduction of 51.8% in 6 hours of reaction, and its configuration is suitable for scale up. Thus, a tubular reactor (artificial radiation and sunlight) was designed and built in semi-pilot scale. This reactor presented a Cr(VI) remediation of 86.7% in 6 hours of reaction under sunlight and showed a photonic efficiency higher than spiral shaped reactor. Additionally, the tubular reactor presented similar photonic efficiency when used with either lamps (5.6%) or sunlight (5.5%), however the reactions under sunlight showed a greater total Cr(VI) reduction when compared to the reactions under artificial radiation. Therefore, the tubular reactor, which was designed and built, proved to be efficient when applied to treatment of real wastewater containing Cr(VI) by photochemical reduction process. Furthermore, the use of a solar tubular reactor minimizes the amount of electricity required for the reaction, which not only reduces process costs, but also makes the technology more environmentally sustainable.
5

Wood We Change? : Business Model Innovation Towards Sustainability Transitions: Studying the Wood Construction Industry

Abadzhiev, Andrey January 2021 (has links)
Innovations based on sustainable technologies have been widely considered as a remedy for addressing societal and environmental problems in many industries. However, the large-scale adoption of such innovations goes beyond technology and requires organizing the business in a way that drive industrial transformations across actors and system layers, such as market structures, institutional frames, consumer behavior, and business values.  The aim of this dissertation is to understand how industrial firms organize for system change towards sustainability. The study is a compilation of two papers within the same research context: the development of sustainable technology in the construction industry. The overlapping unit of analysis for both papers is business model innovation. Paper I examines how industry firms combine and complement business models with different innovation types to accelerate sustainable technology. Paper II identifies how a change in the business model and value creation logic that occur on a firm level accelerate sustainable technology and shape the socio-technical system. Together, both papers help paint a more complete picture of the business model role in transitions towards sustainability. The theoretical frame of this dissertation spans several domains: business model, innovation management, and sustainability transitions. Building on a multi-disciplinary premise, the study takes into account the organizational and the systemic parts of the change process by linking the company perspective (business models) to the wider governance of sustainability transitions.  The findings underline the importance of business models that combine production efficiency with higher customer engagement and more collective value creation for driving larger-scale transitions toward sustainability. Moreover, business models in combination with different innovation types, such as product, process and positioning, act together and complement each other to achieve high sustainability and business outcomes. / Innovations based on sustainable technologies have been widely considered as a remedy for addressing societal and environmental problems in many sectors of our economy. However, the large-scale adoption of such innovations goes beyond technology and requires organizing the business in a way that drives transformations across actors and industries. This dissertation aims to understand how industrial firms organize for system change towards sustainability. The study is a compilation of two papers within the same research context: the development of sustainable wood technology in the construction industry. The overlapping unit of analysis for both papers is business model innovation. Paper I examines how industry firms combine and complement business models with different innovation types to accelerate sustainable technology. Paper II identifies how a change in the business model and value creation logic that occur on a firm level accelerate sustainable technology and shape the socio-technical system. Together, both papers help paint a more complete picture of the business model role in transitions towards sustainability. The theoretical frame of this thesis spans several domains: business model, innovation management, and sustainability transitions. Building on a multi-disciplinary premise, the thesis takes into account the organizational and the systemic parts of the change process by linking the company perspective to the wider governance of sustainability transitions.  The thesis outlines two main contributions. First, the results show that business model innovation acts with and complements different innovation types to achieve high sustainability and business value outcomes. Second, the results reveal that scaling sustainable technologies require combining production efficiency with higher customer engagement and more collective value creation. Combining layers of different value creation logics unlocks the potential of novel technology and shape the entire industry towards more sustainable development.
6

Opportunities for the Jatuwa community biogas plant : An energy demand survey and a field site examinationMinor Field Study

Öhman, Axel, Edwall, Bill January 2018 (has links)
De klimatförändringar som idag orsakar allt större problem för länder i Himalayaregionen har ökat beslutsfattares medvetenhet kring konsekvenserna som de ökande temperaturerna för med sig. När människor konsumerar energi från fossila bränslekällor ökar koncentrationen av bland annat koldioxid i atmosfären vilket bidrar till den växthuseffekt som sakta värmer upp jordens klimat. Detta påverkar ekosystem och ökar risken för naturkatastrofer. Nepal är ett av länderna som ser konsekvenserna av den globala uppvärmningen från nära håll och landet satsar därför på att utveckla energisektorn genom implementeringen av fossilfria energislag. En av de mest framgångsrika satsningarna är användandet av biogasteknologi. Idag har över 350 000 småskaliga biogasanläggningar installerats över hela landet. Alternative Energy Promotion Centre (AEPC), den verkställande myndighetsorganisationen för främjande av ren och hållbar energi satsar nu på att utveckla den storskaliga biogassektorn för att öka landets inhemska och hållbara energiutvinning.   Shree Krishna Gau Sewa Sadan (SKGSS) är en hinduisk stiftelse belägen i byn Jatuwa i sydöstra Nepal vars syfte är att ta hand om och betjäna kor, djur som inom hinduism är betraktade som heliga. Stiftelsen siktar nu på att bli ekonomiskt självförsörjande genom att sälja biogas och rötslam från en nyligen byggd biogasanläggning till närliggande hushåll. Gasen ska produceras från dynga insamlat från stiftelsens kor och distribueras genom ett gasnät som ännu inte är byggt. Syftet med denna studie var att utreda möjligheterna för SKGSS att framgångsrikt driva biogasanläggningen och fokuserade på två områden som var av intresse för AEPC, projektets huvudsponsor. Det första var att primärt beräkna hushållens energibehov för matlagning, deras nuvarande energikostnader för matlagning och deras inställning att byta till biogas som matlagningsbränsle för att assistera planeringen av det framtida gasnätet. Det andra var att lokalisera och identifiera potentiella förbättringsområden inom biogassystemet och baserat på detta ge förslag på huvudsakligen tekniska förbättringar som kan hjälpa SKGSS att framgångsrikt driva biogasanläggningen. Studien genomfördes med hjälp av en litteraturstudie, semi-konstruerade intervjuer, enkätundersökning av hushållen och en inspektion av biogasanläggningen.   Enkätundersökningen visade att hushållens intresse att byta till biogas är stort. De flesta var dessutom villiga att betala för att anslutas till gasnätet. Den positiva inställningen till biogas härrör möjligen delvis från en ökad medvetenhet kring klimatfrågor samt energisäkerhet. Undersökningen visade även att det närliggande området inte är en trolig marknad för försäljning av rötslam. Dock är Nepal en växande marknad för organiskt och högkvalitativ gödsel så möjligheterna för en lyckad försäljning av rötslam är ändå stora. De primära beräkningarna visade att anläggningen med dess idag tillgängliga mängd organiskt material inte kan förse mer än 50 hushåll med biogas. Vid planläggningen av gasnätet måste dock beräkningar baserade på faktiska mätningar av biogassystemet göras. Denna studie rekommenderar även ett antal förbättringar av biogassystemet som skulle kunna hjälpa stiftelsens biogasanläggning att fungera bättre. / As climate change becomes an ever-bigger issue for countries in the south-Himalayan region, policy makers become more aware of the problems associated with increasing temperatures. As countries consume more energy extracted from fossil fuels the climate becomes warmer, affecting ecosystems and increasing the risk of natural disasters. Nepal is one of the countries seeing the effects of global warming from close range and the country is now seriously aiming to develop its energy sector through the implementation of sustainable energies. One of the more successful stories of the Nepali energy sector is the implementation of biogas technology. As of today, more than 350 000 small scale biogas systems for single household use are operating all over Nepal. The Alternative Energy Promotion Centre (AEPC), the focal governmental agency for the promotion of sustainable and clean energy, is now aiming to develop the large-scale biogas sector. This would increase the amount of domestic sustainable energy as well as the country’s energy security.   The Shree Krishna Gau Sewa Sadan (SKGSS) is a Hindu trust located in south-eastern Nepal with the purpose of taking in and serving cows. It now aims to become economically self-sufficient by selling biogas and slurry produced from a newly constructed large-scale biogas plant to the nearby community households. The biogas will be produced from cow dung collected on the property and distributed to the households through a gas grid that is yet to be designed and built. The purpose of study was to investigate the opportunities for the trust to successfully operate the biogas plant and was focused on two areas of interest to the AEPC, which is the key sponsor of the community biogas project. The first was to primarily calculate the energy cooking demand of the nearby households, their current cost of cooking and their attitude towards a switch to biogas usage which would assist the planning of the future gas grid. The second was to localize and identify potential areas of improvements within the biogas system and based on that offer suggestions of improvements focused on technical aspects that would help the SKGSS to successfully operate the biogas plant.The study was conducted using a literature study, semi-constructed interviews, household surveys and on-site inspections of the biogas plant.   The household survey showed that the nearby households’ interest in switching to biogas is high. Most of the households also showed to be willing to pay extra money to be connected to the biogas grid. The positive attitude towards biogas partly stems from a raised awareness about climate issues as well as increased security in energy security. The survey also showed that the nearby urban and semi-urban community is not a viable market for the produced slurry. However, Nepal is a big and growing market for organic high value fertilizer so the potential of a successful sale of slurry is still high. The primary calculations show that with the feedstock available, the community biogas plant cannot suffice more than 50 households’ energy demand for cooking. When designing the gas grid, proper calculations based on actual measurements of the biogas system need to be done. This study also recommends various improvements of the biogas system that will help the SKGSS biogas plant to operate successfully.
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Envisioning Catalytic Processes in Chemical Looping Systems: Material and Process Development

Baser, Deven Swapneshu 05 October 2020 (has links)
No description available.
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Development of Sustainable Traffic Control Principles for Self-Driving Vehicles: A Paradigm Shift Within the Framework of Social Justice

Mladenovic, Milos 22 August 2014 (has links)
Developments of commercial self-driving vehicle (SDV) technology has a potential for a paradigm shift in traffic control technology. Contrary to some previous research approaches, this research argues that, as any other technology, traffic control technology for SDVs should be developed having in mind improved quality of life through a sustainable developmental approach. Consequently, this research emphasizes upon the social perspective of sustainability, considering its neglect in the conventional control principles, and the importance of behavioral considerations for accurately predicting impacts upon economic or environmental factors. The premise is that traffic control technology can affect the distribution of advantages and disadvantages in a society, and thus it requires a framework of social justice. The framework of social justice is inspired by John Rawls' Theory of Justice as fairness, and tries to protect the inviolability of each user in a system. Consequently, the control objective is the distribution of delay per individual, considering for example that the effect of delay is not the same if a person is traveling to a grocery store as opposed to traveling to a hospital. The notion of social justice is developed as a priority system, with end-user responsibility, where user is able to assign a specific Priority Level for each individual trip with SDV. Selected Priority Level is used to determine the right-of-way for each self-driving vehicle at an intersection. As a supporting mechanism to the priority system, there is a structure of non-monetary Priority Credits. Rules for using Priority Credits are determined using knowledge from social science research and through empirical evaluation using surveys, interviews, and web-based experiment. In the physical space, the intersection control principle is developed as hierarchical self-organization, utilizing communication, sensing, and in-vehicle technological capabilities. This distributed control approach should enable robustness against failure, and scalability for future expansion. The control mechanism has been modeled as an agent-based system, allowing evaluation of effects upon safety and user delay. In conclusion, by reaching across multiple disciplines, this development provides the promise and the challenge for evolving SDV control technology. Future efforts for SDV technology development should continue to rely upon transparent public involvement and understanding of human decision-making. / Ph. D.
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Decision making when investing in sustainable technology within the building sector

Nilsson, Henrik, Nordlund, Henrik January 2012 (has links)
The housing and service sector in Sweden are estimated to be responsible for 40 % of the total primary energy usage (Energimyndigheten, 2011). There exist a lot of inventions that have the possibility to greatly improve the environmental performance of a building´s LCA (Life Cycle Assessment) (Swentec, 2012) (Rutqvist, 2008). In order to achieve implementation of new innovative sustainable installations in buildings it is important to understand the process during the investment decision. Understanding the decision making process used in practise, is the first step towards creating a strategy for how to get a new technology implemented. By conducting a survey including both contractors and developers in Sweden an overview of the building sectors standpoint on environmental sustainability is achieved. In order to refine the information and achieve a more detailed picture of the issue the survey was followed up by In-depth interviews.The findings show that valuation techniques are varying a lot between companies but surprisingly many of the companies do use inferior methods such as pay back-time for investment calculations. Overall in the construction business technical and economic risk aspects are not being valued explicitly but rather through the use of product ratings and brand promise of well-known suppliers. Negative externalities are not being included in the calculations and the valuation of intangibles is not done explicitly but rather seen as implicitly derived from the cost and value of sustainability certifications.
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Lost & Found Videothek Non-Ubiquitous Video Library for Serendipitous Retrieval of Movies. A Design Exploration for the Introduction of Folksonomy in the Physical Space

Di Giovanni, Bianca January 2017 (has links)
Lost&Found Videothek is the concept for an interactive video library thought for users engaged in an exploratory research mode, in which content is organized according to a collaborative, subjective and implicit indexing system for the enhancement of serendipity. This idea was the result of a design-based research with a user-centered approach in the field of information retrieval. With the use of design methods such as heuristic UX evaluation, co-sketching, and other original design experiments, the project aimed at identifying the most valuable qualities of physical and digital libraries in order to integrate them within one retrieval system.

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