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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.
51

Green Packaging Development. : A way to efficient, effective and more environmental friendly packaging solutions.

Mian Muhammad, Masoud January 2011 (has links)
Growing pressure on the packaging design to enhance the environmental and logistics performance of a packaging system stresses the packaging designers to search new design strategies that not only fulfill logistics requirements in the supply chain, but also reduce the CO 2emissions during the packaging life cycle. This thesis focuses on the packaging design process and suggests some improvements by considering its logistics performance and CO 2emissions. A Green packaging development model was proposed for corrugated box design to explore the inter-dependencies that exist among compressive strength, waste and CO2emissions. The verification of the proposed model unveils the significance of a holistic view of the packaging system in the packaging design process and reveals the importance of packaging design decisions on the logistics performance and CO 2 emissions. The thesis finally concluded that the packaging logistics performance should be considered in a packaging design process to explore the Green packaging design solution.
52

CO2-utsläpp från transporter som uppstår på grund av processlöserier

Höglund, Rebecka, Allanson, Louise January 2021 (has links)
he company in the study seek to work more sustainable by minimizing transportations. They aim to reduce their CO2 emissions by 50%, independently on sold volume, by 2030, with 2019 as the year of reference. This report is about Epiroc Rock Drill AB’s sustainability goals inspired by Agenda 2030 and how their process deviations result in unnecessary transportations that negatively affect the environment with CO2 emissions. Epiroc Rock Drills AB aspires to gain an understanding of which process deviations lead to unnecessary transports and how much CO2 emissions they generate. In order to fulfil the aspiration, a description of the current situation was formed in which it is possible to distinguish in which parts of Underground's processes need of transportations appear and why. An analysis of the current situation was then needed to be able to answer the question of what process deviations affect Underground’s transportation needs and how much CO2 emissions they generate. To determine how much CO2 emissions the process deviations generated, a quantification of the CO2 emissions that emerged from process deviations in 2019 was included in the current situation analysis. The conclusions from the thesis were that the areas of lack of quality, delayed material, warehousing, quality assurance and washing, scrapping and 90-kits cause process deviations and affect Underground's transport needs and CO2 emissions. Summarized, the areas generated 3332 tonnes of CO2 emissions. The areas of lack of quality, delayed material and 90-kits caused the greatest amount of CO2 emissions which amounted to 3169 tonnes. The work carried out has created a foundation that Underground can continue to work with in the area of transport to achieve the goal of halving their CO2 emissions. The next step is to work with the process deviations that has been presented to minimize or eliminate them. / Företaget i studien strävar efter att arbeta mer hållbart genom att bland annat minimera transporter. De har som mål att år 2030, oberoende av såld volym, halvera sina CO2-utsläpp i linje med Agenda 2030 med 2019 som referensår. Denna rapport handlar om Epiroc Rock Drills AB:s hållbarhetsmål inspirerade av Agenda 2030 och hur deras processlöserier medför onödiga transporter vilket påverkar miljön negativt med CO2-utsläpp. Epiroc Rock Drills AB önskar att få förståelse för vilka processlöserier som leder till onödiga transporter och hur mycket CO2-utsläpp de genererar. För att uppfylla önskemålet framställdes en nulägesbeskrivning i vilken det går att utläsa i vilka delar av Undergrounds processer ett behov av transporter uppstår och varför. Med nulägesbeskrivningen som grund identifierades processlöserier som påverkar Undergrounds transportbehov och hur stora CO2-utsläpp de genererar. För att veta hur mycket CO2-utsläpp processlöserierna genererade inkluderades en kvantifiering av CO2-utsläppen som uppstod av processlöserier 2019 i nulägesanalysen.   Slutsatserna från examensarbetet var att områdena kvalitetsbrist, försenat material, lagerhållning, kvalitetssäkring och tvättning, skrotning och 90-kit orsakar processlöserier och påverkar Undergrounds transportbehov samt CO2-utsläpp. Tillsammans genererade områdena 3332 ton CO2-utsläpp. Områdena kvalitetsbrist, försenat material och 90-kit orsakade störst mängd CO2-utsläpp och uppgick till 3169 ton. Arbetet som genomförts har skapat en grund som Underground kan fortsätta arbeta med inom området transport för att nå målet att halvera sina CO2-utsläpp till 2030. Nästa steg är att arbeta med de processlöserier som lyfts för att minska eller eliminera dem.
53

Vad är konsekvenserna av samlastning och hur uppfattas det av slutanvändare

Hultgren, Julian, Frennessen, Max January 2019 (has links)
Transportsektorn är en av de sektorer som står för en stor andel utsläpp. Transporter står för cirka en tredjedel av Sveriges utsläpp av växthusgaser. För att minska denna siffra har flera kommunala samt privata initiativ startats. Ett av dem är företaget i fråga som detta arbete är gjort tillsammans med.Huvudsyftet med vårt arbete var att ta fram faktisk data i form av en simulering för att kunna styrka att detta privata initiativ faktiskt var ett grönare alternativ samt att kunna förmedla detta på ett bra och metodiskt sätt för användaren via en prototyp. Simuleringen gjordes på äldre data från företaget på faktiskt körda transporter. Prototypen är ett interaktivt verktyg för användaren för att se vilka effekter deras tänkta agerande kan åstadkomma. Kan man nu med denna prototyp få användare att bli mer villiga att använda sig utav tjänsten? Och är de beredda att betala mer när de ser vilka effekter det skulle ge? Detta undersöktes i form utav en användarundersökning. Vad simuleringen visade var att samlastning av gods är avsevärt mycket bättre gällande Co2-utsläpp, än att transportera godset själv. Utöver detta visade prototypen i samarbete med användarundersökningen att slutanvändare tyckte om utformningen utav prototypen samt att budskapet förmedlades, dvs vilka minskade Co2 utsläpp som kunde göras. Våra resultat visar på att budskapet om Co2:s påverkan hade tagit emot av användarna. Samt att de var villiga att betala 21% högre belopp för dessa typer av tjänster, med motivering att det skulle vara bra för miljön. / The transport sector is one of the sectors that accounts for a large proportion of emissions. The transport sector accounts for about one third of Sweden's greenhouse gas emissions. To reduce this figure, several municipal and private initiatives have been started. One of them is the company in question with which this work has been written.The main purpose of our work was to produce actual data in the form of a simulation in order to prove that this private initiative was actually a greener alternative, and to be able to convey this in a good and methodical way for the user via a prototype. The simulation is done on older data from the company on actual transports. The prototype is an interactive tool for the user to see what effects their intended actions can bring. With this prototype, can users now be more willing to use the service? And are they prepared to pay more when they see what effects it would give? This was tested in the form of a user survey. This meant that the user was first asked about why they would like to use this form of service and what sums they were prepared to pay for a specific transport.Then they sat down and tested the prototype and entered various transports and goods to transport then saw what effects they had. Then they were asked what they thought of the prototype and the information they received, and what motivations they had to use the service or similar services. Lastly they were asked what amounts they were prepared to pay for this form of service.What the results show is that the simulation resulted in the collective transportation of goods being considerably much better with respect to Co2 emissions, than if it were to be transported by itself. In addition to this, the prototype in collaboration with the user survey showed that end users liked the design of the prototype and that the message that was conveyed, ie which reduced Co2 emissions could be done. This ended with the users' motivations for using this or similar services were similar to before, but this turn Co2 jumped up to one of the leading reasons, even when it wasn't a motivation at all before when they stated before they tested the prototype. As well as they were now willing to pay up to 21% higher amount for these types of services, justifying that it would be good for the environment.
54

A revision of the first three phases in the European Union’s ETS and its effects on the CO2 emissions within the Swedish and Finnish Pulp & Paper industry.

Blanking, Oscar, Stålberg, Samuel January 2023 (has links)
The European Emissions Trading Scheme (EU ETS) aims to lower greenhouse gases inpollution-intensive industries. The success of the EU ETS, its policy framework and its pricingstrategy is both empirically acknowledged and disputed. The study contributes to the empiricalresearch on the effect of the price of EU ETS permits on carbon emissions. Therefore, the aimis to establish the relationship between the price of emission permits and CO2 emissions inrelation to each phase of the EU ETS, for Sweden and Finland with a focus on the Pulp andPaper Industry (PPI). Moreover, the focus lies on the difference in the effect of each EU ETSphase on CO2 emissions, allowing for discussion on the effectiveness of each phase. Using aNewey-West multiple linear regression analysis, we found statistically significant evidence thatduring Phase 3, EU ETS permit pricing had a negative effect on CO2 emissions for both Swedenand Finland, EU ETS permit pricing in Phase 1 seems to have a low positive effect on CO2emissions solely for Sweden, while Phase 2 does not have an effect on CO2 emissions for eithercountry. Our collected data implies some degree of ineffectiveness and uncertainty in thesuccess of the EU ETS framework and pricing strategy.
55

Integrated analysis of bioclimatic building design in three climate zones in France

Chaneac, Jean January 2012 (has links)
ABSTRACT At a time where the planet is facing one of its major global crises, re-thinking of systems in every sector is needed. In the field of energy at its global meaning, various ways of action are considered. In this context, housing sector represents a key point of new conception of our society. Nowadays buildings are no longer considered only as designed housing "objects". Comfort, consumption, environmental impacts are part of the words which appear utterly linked to every single building. Thermal behaviour tends to be as much important as architectural and structural concerns. Indeed, energy savings have become one of the most talked about parameters of a building. Through this paper, key parameters of a building will be compared in order to obtain the most effective houses depending on their location. Nevertheless, comfort will be studied too because of its increasing importance in modern society. The results will be obtained according various aspects: technical ones, environmental ones and financial ones. For all those houses meeting the French standards, similar comparison will be made. Thus the approach will not be organised one house after another but through the impact of one parameter after another to draw the final comparison between the three houses according to the same parameters. Keywords: energy consumption, CO2 emissions, sustainable systems, bioclimatic buildings
56

Reduction of CO2 emissions via cross-sector integration of community and industrial energy systems

Li, Ruonan January 2023 (has links)
Integrating energy across different sectors is an efficient solution for improving energy systems to meet energy demands with low CO2 emissions. Such integration includes combining the supply and demand of heating, cooling, and electricity by implementing appropriate equipment, as well as combining the energy systems of civic and industrial sectors. This thesis develops various optimization approaches to identify the optimal design and operation of distributed energy systems and the integration of energy systems across commercial, industrial, and transportation sectors, which minimize CO2 emissions and costs of the systems. Available equipment of the energy systems includes combined cooling, heating, and power system, absorption chiller, solar thermal collector, photovoltaic, boiler, electric chiller, battery, ground source heat pump, and air source heat pump. This thesis provides the following contributions to this area. (1) Identify optimal structures of distributed energy systems under different electric grid CO2 footprints. The work implements representative periods when formulating the energy system, which reduces computation time. (2) Differentiate heating demands of entities in the integrated system at different temperature levels to ensure feasible heat transfer. It removes the simplified assumptions in existing studies on the integrated energy system that assume all heating demands are at a uniform temperature. (3) Optimize production rates of plants instead of assuming steady industrial production rates. The switchable production rates lead to a further reduction in CO2 emissions of the integrated system. (4) Identify the environmental and economic benefits of the integrated operation under different electric grid CO2 footprints. It presents that integrated operation reduces more CO2 emissions when the electric grid has higher CO2 footprints. (5) Identify the optimal relative sizes of entities in the integrated system that maximize the CO2 emissions reduction benefits brought by the integrated system. (6) Prove the integrated system has lower CO2 emissions than individual energy systems both under deterministic and stochastic scenarios. Overall, the work in this thesis contributes to developing energy systems and integrated energy systems with the lowest possible CO2 emissions under various scenarios. / Thesis / Doctor of Philosophy (PhD) / As the total population continues to increase worldwide, it is necessary to improve community energy systems to reduce CO2 emissions when meeting energy demands. An efficient solution is integrating energy systems across different sectors. This work explores novel structures of energy systems – integrated energy systems that combine the supply and demand of heating, cooling, and electricity in residential, commercial, industrial, and transportation sectors. The optimal energy system configurations, sizes of subsystems, production rates of plants, heat transfer and electricity transfer, as well as capacity and operation of the equipment, have been identified by developing optimization approaches that minimize CO2 emissions and costs of the integrated system. The optimal design and operation are found under both deterministic and stochastic scenarios and different grid electricity generation scenarios, which provide references for developing community energy systems with the lowest possible CO2 emissions under various scenarios.
57

New Polygeneration Processes for Power Generation and Liquid Fuel Production with Zero CO2 Emissions

Khojasteh Salkuyeh, Yaser 06 1900 (has links)
The price and accessibility of fossil fuels, especially crude oil, are subject to considerable fluctuations due to growing demand on energy, limited resources, and energy security concerns. In addition, climate change caused by burning of fossil fuels is a challenge that energy sector is currently facing. These challenges incentivize development of alternative processes with no greenhouse gas emissions that can meet transportation fuels, chemical liquids, and electricity demands. Coal-based processes are of particular interest because coal price is both low and stable. However, these processes have a large environmental impact and are also less economically attractive than natural gas based plants due to the recent significant drop in natural gas price. However, even for natural gas plants, attempts to reduce CO2 emissions by using traditional CO2 capture and sequestration technologies not only decrease the thermal efficiency and profitability of the plant significantly but still release some CO2 to the atmosphere. The aim of this thesis is to develop, simulate and optimize an integrated polygeneration plant that uses multiple feedstocks and produces multiple products with low to zero CO2 emissions. Several process alternatives are investigated in this work to show the effect of each feedstock and product on the performance of the proposed plant. A comprehensive study is performed in each section, including process simulation in Aspen Plus software, development of custom models required for some units, as well as cost analysis by using Aspen Icarus software and empirical cost estimations from literature. Moreover, derivative free optimization techniques such as particle swarm optimization (PSO), genetic algorithm (GA) and simulated annealing (SA) are implemented to drive the design to economically optimum conditions as a function of the market price and carbon taxes. The final model will also introduce emerging technologies that can achieve higher efficiency and lower CO2 emissions compared to commercial systems, such as chemical looping gasification, chemical looping combustion, nuclear heat reforming, etc. By integrating multiple feedstocks and processes, the model can exploit certain synergies which are unavailable to traditional plants, resulting in significant efficiency improvements. In addition to power and liquid fuels, this polygeneration process offers benefits for petrochemical plants. Despite limited worldwide crude oil reserves, the demand for petrochemical products is still growing fast and it is highly important for petrochemical industry to find new resources as feedstock and diversify their supply chain network. By integration of the polygeneration plant in the same facility with novel processes that produce olefins (petrochemical feedstock) not from oil, but from syngas, it is possible to supply the required feed at lower cost than commercial steam cracking plants. / Thesis / Doctor of Philosophy (PhD)
58

Pros and Cons of Using Large Concrete Blocks in an Office Building Structure : Comfort, Stability, Sustainability

Baban, Shwan, Abolfazl, Asliyalfani January 2023 (has links)
In 2019, the cement industry used 280 million tons of oil equivalent, contributing to 7% of totalindustrial energy consumption. This resulted in 2.4 billion tons of CO2 emissions, constituting26% of the industrial sector’s CO2 output and 7% of global energy-related emissions. On theother hand, It is affordable, safe, and readily available, thanks to its construction error resistance. C3C is a company that takes advantage of waste concrete that has been produced and useit to mold concrete blocks that has different functions. This is a big environmental benefit. Themain function of these blocks has been to function as temporary or permanent partitions walls orsafety walls for accidental loads. The aim of this study is to investigate the feasibility and performance of a temporary office structure that is built majorly out of these C3C lego blocks froma comfort, stability and sustainability point of view. This data aids construction professionalsseeking cost-effective alternatives to traditional methods. Retrofitting and cascading offer economic and environmental benefits. Our goal is to discover innovative, sustainable constructionapproaches for future generations. The results show the importance of insulation positioning forthe comfort point of view. To ensure stability and analyse if the separation of the blocks occur,four RFEM models are made with focus on the tensile stresses and uplifting deflection of thewalls. In conclusion, this study provides ideas on how to design a temporary structure usingC3C lego blocks.Keywords: Concrete blocks, C3C blocks, FE models, life cycle analysis, mechanical connections, CO2 emissions.
59

The effects of sector free allowances & emissions on stock returns : A study on firms which partake in the EU emissions trading system

Milic, Mario, Stjernberg, Noah January 2023 (has links)
This study aims to investigate whether sectorial free allowances and sector emissions have any effect on a firm's stock return under the newly introduced EU ETS (Emission trading system). In doing so, the data have been structured as panel data and are gathered for a sample period of 10 years measuring from 2012-2021, looking at 6 sectors (Aviation, Combustion of fuels, refining of mineral oil, production of cardboard/ paper, production of pig iron and steel and production of bulk chemicals). The main empirical results indicate that free allowances have a positive effect on stock returns while sector emissions are insignificant. When categorizing the firms into low, medium and high emitters the results indicate that the medium category follows the main results, while low emitters are negatively affected by sector emissions with free allowances being non-significant. We observe no effect on either free allowance or sector emissions on firms’ stock returns within the high emitting category. To conclude, we find evidence indicating that free allowances have a positive effect on stock return while sector emissions do not.
60

Grain sorghum-cowpea intercrop : a climate-smart approach for enhanced productivity, physiological responses, and carbon dynamics under planted and simulated no-till conditions

Mogale, Tlou Elizabeth January 2022 (has links)
Thesis (Ph.D. (Plant Production)) -- University of Limpopo, 2022 / Sustainable food production has been a major challenge in the era of climate change and a growing population in the twenty-first century. However, climate change scenarios such as extreme temperatures and fluctuations in annual precipitation continue to pose a great threat to agricultural production systems. On the other hand, anthropogenic activities such as conventional farming continue to contribute to climate change through the emission of greenhouse gases while not sustaining agricultural production. The Food and Agriculture Organization of the United Nations (FAO-UN) developed the concept of Climate-Smart Agricultural (CSA) production with the idea of securing food in the face of global change. No-tillage and intercropping systems are among the traditional practices that are advocated as components of climate-smart traditional practices, especially in the semi-arid regions of Africa like the Limpopo Province. Producing sorghum and cowpeas using CSA practices such as intercropping under no-tillage is envisaged to increase productivity and soil fertility under Limpopo Province's dryland conditions. However, there is still limited information on how grain sorghum-cowpea intercrop will respond in terms of growth, physiological productivity, and carbon dioxide emissions in the system, especially under no-tillage and different growing conditions. Furthermore, more field data is required for predictions of future scenarios using simulating crop models such as the Agricultural Production system sImulator (APSIM). Hence, a no-till Randomized Complete Block Design (RCBD) in a 2 x 4 x 2 factorial arrangement was conducted at two locations (Syferkuil and Ofcolaco) in the Limpopo Province during the 2018/19 and 2020/21 cropping seasons to generate data on sorghum and cowpea growth, physiology, productivity as well as carbon dynamics under planted and simulated intercropping system. Leaf gaseous exchange and leaf area index (LAI) were measured on fully developed grain sorghum and cowpea leaves in both the binary and sole cultures of sorghum and cowpea. The CO2 measurements were taken from each plot using a GMP343 CO2 probe along with an MI70 data logger. Aboveground biomass was collected for each crop from two plants at vegetative, flowering, physiological and harvest maturity and oven-dried at 65 oC for 48 hours. In the 2020/21 cropping season, cowpea at Ofcolaco failed to produce grain. Hence, only the grain yield of the 2018/19 cropping season from Ofcolaco is presented in this thesis. Grains collected for each crop from a 2.7m2 area were taken to the laboratory to determine grain yield and yield components. Harvest index (HI) and land equivalent ratio (LER) for each crop were also determined. In the laboratory, the total nitrogen (%) and natural abundance of 15N (δ15N‰) were determined using an isotope ratio mass spectrometer with an N analyzer. Growth (biomass) and yield (grain) data obtained from APSIM were compared with data collected from a two-year field experiment at Syferkuil. Multi-variate analysis of variance (ANOVA) model to fit each response variable using the Statistical Analysis System (21 SAS version 9.4). Mean separation was done where the means were different using the least significant difference (LSD) at probability levels of p ≤ 0.05. Intercropping system and the density of the companion crop cowpea had a significant (p ≤ 0.05) effect on the physiological responses of sorghum and cowpea, cowpea yield and yield components at the two experimental sites across seasons. However, grain yield and yield components of sorghum were not affected by intercropping or the density of cowpea. Only cultivars of sorghum were significantly different for grain yield and yield components. At Syferkuil, Enforcer produced the highest grain yield of 4338 kg ha-1 in 2018/19, while NS5511 accumulated the highest grain yield of 2120 kg ha-1 during the 2020/21 cropping seasons. At Ofcolaco, Enforcer and Avenger were observed to be relatively high-yielding cultivars with a mean grain yield of 2625 kg ha- 1 and 1191 kg ha-1 during the 2018/19 and 2020/21 cropping seasons, respectively. In the 2018/19 and 2020/21 cropping seasons, respectively, cowpea accumulated about 93% and 77% more grain yield in sole compared to binary culture. At Ofcolaco, about 96% more grain yield was obtained in sole compared to binary cultures during the 2018/19 cropping season. Furthermore, cowpea accumulated over 55% and 49% of grain yield when grown at high compared to low population density at Syferkuil and Ofcolaco, respectively. The investigation on the impact of the intercropping system on CO2 emissions and soil carbon stocks revealed that in 2018/19 at Syferkuil and 2020/21 at Ofcolaco, intercropping systems emitted 11% and 19% less CO2 respectively than the sole cropping systems. In both diverse agro-ecological sites, low cowpea density consistently resulted in higher CO2 emissions than high density. The sorghum-cowpea intercropping system significantly influenced the biological nitrogen fixation of cowpea. Intercropping was found to improve the biological nitrogen fixation of cowpea if a density of 74074 plants ha-1 is used. The APSIM model was able to capture the dynamics of biomass and grain yields in the sole and intercropping system under different densities of cowpea. The findings of this study revealed some useful insights. Firstly, biomass accumulation depended on the cultivar in intercrop as well as the density of cowpea. Secondly, cowpea at a density of 74074 plants ha1 was found to be a good crop to intercrop with grain sorghum as it did not show any significant variation in terms of grain yield and yield components of sorghum. The sorghum cultivar, Enforcer and NS5511 were the best performing cultivars in terms of grain yields at Syferkuil and Ofcolaco. Thirdly, the intercropping system under high cowpea density reduced CO2 emission rates while improving soil nitrogen (N) and carbon stocks. Based on the results of this study, grain sorghum-cowpea intercrop can be adopted as a component of a climate-smart practice to improve crop growth, physiology, as well as productivity compared to sole cropping. However, the grain sorghum cultivar and the density of cowpea should be taken into consideration as they affect the productivity of the two crops. The two seasons data generated from this study was useful in simulating the productivity of intercropping practice using APSIM. However, more field and weather data is required to run long-term simulations on intercropping as a component of the climate-smart method using crop modelling techniques. / National Research Foundation (NRF), Departments of Science and Innovation (DSI) and VLIR-IUC (Belgium)

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