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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.
11

The Present and Future Role of Energy Recovery in Waste Management - A Case Study of Linköping and Norrköping

Molin, Johan January 2015 (has links)
In the European Union 500 million tonnes of waste are either incinerated without energy recovery,or deposited in landfills, which could have been recycled instead. The European Union initiated theCircular Economy Package in order to decrease the amount of waste being generated, lost inlandfills, and to increase the recycling and usage of recycled material. However, the CircularEconomy Package did not contain any targets focusing on energy recovery, and only mentionedenergy recovery as having a role in decreasing the amount of waste deposited in landfills. TheCircular Economy Package was in the end of 2014 withdrawn but will come back with moreambitious targets. In Sweden energy recovery is treating more than 50% of the municipal waste andwould then be affected by the targets of the Circular Economy Package when it comes back.This thesis focuses on Linköping and Norrköping to identify the what role energy recovery have inthese municipalities, both present and future, as well as asking the questions of how waste is valuedas a resource.The results were that both municipalities thought that it was important to have separate sorting ofmunicipal waste, to separate organic waste from the rest, in order to use it in material recycling andthe rest in energy recovery. In both municipalities the energy recovery had the role of treating themunicipal waste which was found to be not recyclable, as well as to deliver heat and electricity. Allof the organisations were identified to have a high environmental value on waste, but the economicvalue of waste were low or negative. The municipalities also knew little of the Circular EconomyPackage, but were aware of it, while the energy companies knew a little more of it, but still littlecompared to their national interest organisations Avfall Sverige and Svensk Fjärrvärme. All of theorganisations had identified similar challenges such as increased focus on recycling, minimisationof waste, but also a focus on decreasing amount of hazardous substances in products in order todecrease the amount of waste which needed to be deposited in landfills.
12

A framework to design reverse logistics operations based on circular economy values

Ripanti, Eva Faja January 2016 (has links)
Reverse Logistics (RL) is complex to be managed due to the uncertainty involved e.g. the quality range of products, timing of product returns, and volume of returns. A robust RL design can contribute to increase the effectiveness of RL operations. Therefore, an RL design framework needs to be formalised. Circular economy (CE) focuses on supporting the separation of treatments between technical and biological materials in maximising the design for reuse to return to the biosphere and retain value through innovations across fields. The aim of the research is to develop a new framework to design RL operations based on CE values that can increase the effectiveness and efficiency of RL operations. This research has been conducted through the qualitative research involving cases in product recovery (PR) options that are analysed in-depth. Literature review and interview are the main methods of this research. A test was conducted by interviewing expert and respondents to obtain the expert view and test the research result which is a developed framework to design RL based on CE values. The testing engaged five criteria (usability, feasibility, consistency, effectiveness, and utility). The formal RL design framework, 15 CE values, framework to design RL based on CE values specifically PR options (repair, refurbishment, remanufacturing, and cannibalisation) are main research findings. The research contributes academically to the development of a formal RL design framework and to the identification, reformulation, redefinition, and implementation of CE values. The research can be used as a basis for an effective design of RL that takes into account the economic, environmental, and social impacts. The research can be used as a guideline or an appraisal tool in designing/modifying RL based on CE values that can support the implementation of a single RL operation and also RL based on CE.
13

Moving beyond sustainability: To what extent does the Cradle to Cradle framework play a role within New Zealand's fashion industry?

Dransfeld, Josephine Gisela January 2015 (has links)
Our planet is threatened by a rapidly changing climate, alarming resource depletion and a steadily rising population growth. This calls for intensified sustainable practices within businesses of all sizes and industries. In recent years this resulted in a wholly new model called the circular economy. Inherent to this is the Cradle to Cradle framework which seeks to design and create commodities in such a way that the impact on the environment, i.e. the carbon footprint is neutralised. Significant efforts are currently being undertaken in Europe and the United States in various sectors with a recent focus on transforming the fashion industry. The literature finds that that there is generally still little known in this area, there was barely any evidence of this change taking in New Zealand. The objective of this research is to explore this and to eventually build a theoretical understanding to what extent Cradle to Cradle plays a role within the fashion industry. This was achieved by employing the grounded theory method. Data was collected by conducting semi-structured interviews with owners-managers supplemented by secondary data such as sustainability reports. In line with grounded theory principles, open and selective coding, theoretical sampling and constant comparison were used to analyse all data within the Nvivo 10 Software. The theory showed that somewhat severe resource constraints and an occurring loss of transparency by outsourcing manufacturing operations to overseas locations impede the shift towards the circular economy at present. This research contributes to sustainable development literature by providing a comprehensive model of how the uptake of sustainable practices is influenced and dependent on multiple aspects and therefore fosters the understanding of a complex, intertwined and intransparent industry. Furthermore, this research benefits companies and business networks alike.
14

Attitudinal perception of cosmetic wear and damage of materials within the use phase of portable electronic products

Manley, Alan H. G. January 2018 (has links)
During the use phase of products, a series of obsolescing factors contribute to why a product is disposed of. Currently the visual state of a product is considered primarily in terms of aesthetic obsolescence which is synonymous with influential factors such as changes in fashion or personal preferences in style. The physical condition of a product is not commonly understood within the context of product replacement and the physical changes due to use are not understood fully. The research contributes to and provides original empirical research findings for the current literature on product lifetime extension, material semantics, the circular economy, emotionally durable design and material culture. Through an initial exploratory study (Photographic Analysis (PA) Study) of previously unexplained types of wear and damage that occur on portable electronic devices a taxonomy of damage (TOD) was established which provided the nomenclature for further studies. The second study (Retrospective Assessment (RA) Study) established the attitudes to wear based on the wear type, location, material and the stage during ownership that the wear occurred at. The RA Study highlighted the differences in the attitudinal responses to differing types of wear and damage and identified the differences in the temporal assessments of wear and damage. A third study (Real Time Assessment (RTA) Study) aimed to confirm or repudiate the findings found in the RA Study. The focus during the study was attitudes to the wear and damage in relation to the differences in materials, the location of the wear and the type of wear and damage was also looked at and led to a fuller understanding of how products and materials are perceived during the use phase; a stage of the product lifetime that is not currently well understood in terms of users aesthetic or cosmetic sensibilities. The final study (Semantic Perception of Materials (SPM) Study) focused on the visual and tactile perceptions of materials. The study established attitudinal perceptions of wear and damage of materials with a quantitative research methodology which has produced a better understanding of material semantics within the context of electronic objects. Through the four studies, discussion topics arose and major findings of the doctoral study were drawn out and seen to be interesting enough for further research and study. These discussions include the importance of including cosmetic obsolescence into the lexicon of product obsolescence and product lifetime extension literature, the differences in the perceptions of materials when they are within the context of a product or being assessed as samples, how differing product contexts affect user perceptions of wear and damage on materials and the potential inclusion of a material wear index that could inform the material selection process that goes further than the technical aspects outlined in current material selection tools and literature.
15

What is ciruclar economy? - The discourse of circular economy in the Swedish public sector

Persson, Ola January 2015 (has links)
The aim of this study is to analyze how the concept of circular economy is viewed and defined within the Swedish public sector. Discourse analysis was applied to the semi-structured interviews conducted with employees who work with circular economy projects at local, regional and national institutions. The research found that circular economy was perceived as a way to face resource limitations through continuous circulation of materials, which could also foster economic growth decoupled from extraction of finite resource. Actors perceived as important for the transition to a circular economy are: public sector, business, researchers and civil society, who are believed to be motivated by the notion that a circular economy will lead to a more sustainable society. Furthermore, it is assumed that different partners will work together towards the common goal of circular economy. In addition, the circular economy concept seems to offer a different rhetorical way of approaching environmental problems. The implications of this study could be used to deepen understandings of how circular economy could be implemented.
16

Cirkulär ekonomi : Vad påverkar kommuners arbete med den ekonomiska modellen?

Johansson, Felicia January 2018 (has links)
The purpose of this study was to examine and compare what causes some municipalities to work with and market their sustainability work in circle economy and what causes some other municipalities not to do so. The study focused on six municipalities, three who worked with and marketed their sustainability work and three who didn’t. Through telephone interviews a representative from each municipalitiey answered; how they defined circular economy, what drove/not drove them to work with circular economy, what difficulties there is with circular economy in the public sector and how the municipalities work can be improved. The results showed that the definition of the economic model was about the same, what differed was their knowledge about the importance of product design. Knowledge and interest in circular economy was two of the causes of why municipalities worked with the model. The fact that the issue was not a priority and the lack of resources from politicians seemed to be two determining factors of why the municipalities’ interest in working with circular economy was small. Sweden’s government needed to act in the question and focus more on top-down instead on today’s down-top work. The municipalities needed to get guidelines and support to make decisions that promoted circular economy since it was an important part of a sustainable development.
17

Integrering av konceptet cirkulär ekonomi i ett globalt konsultföretag

Sjöberg, Emma January 2018 (has links)
The current linear “take, make and dispose” economic model is not sustainable, therefore we need to move towards a circular economy. The society faces a major challenge and as experts and advisors to the society, the consultancy companies play a key role in the transition. The purpose of this study was to investigate how a consultancy company work with the circular economy concept today and how the concept further can be integrated into the company to meet future challenges. Qualitative interviews with eleven representatives from the consultancy company Ramboll were made. All the interviews were recorded and the collected data was analyzed in a qualitative analysis. The results showed a high awareness of the circular economy concept and that Ramboll can offer customers help in their progress towards a circular economy. The demand of circular services is currently low but it will probably increase in the future, both with respect to existing services but also new types of assignments.To meet the future demand the company needs to ensure knowledge within the company, raise awareness and concretize the concept throughout the company. The Nordic countries have an opportunity to be the forerunner in the transition to a circular economy but to do so, one must focus on the issue. If Sweden seriously starts to strive for a circular economy, much help and support will be needed and the consulting companies can be very helpful if they are prepared and have the competence.
18

Phosphorus and Carbon Capture from Synthetic Municipal Wastewater by Carbonate Apatite Precipitation

Ross, Jessica January 2017 (has links)
The world’s 7 billion inhabitants depend on chemical fertilizers to meet the growing demand for food. The phosphorus used in fertilizer is sourced from ancient sedimentary deposits of Phosphate Rock (PR), largely in the form of carbonate calcium phosphate, called carbonate apatite, which resembles bone. PR is non-renewable and Canada’s reserves are extremely limited; currently, all 1,400,000 tonnes of phosphorus products used annually are imported. This project investigates a novel method to recycle phosphorus from municipal wastewater in a form that will enable its reuse as a fertilizer, through a reaction with CaCO3 from limestone and waste CO2 (g). This will contribute to the nascent circular nutrient economy within Canada. A review of the current state of phosphorus and nutrient recycling is presented, including a plan for establishing the Canadian Nutrient Platform. A series of inorganic phosphate (PO4-, or Pi) solutions was prepared to simulate the concentrations found in Ottawa’s municipal wastewater, between 2.5-30 mM Pi. These solutions were mixed with CaCO3 solutions that were highly supersaturated through a carbon capture technique. Batch tests successfully reduced the [Pi] and [Ca2+], as measured by colorimetry, and precipitate formed. These results were subsequently repeated in a continuous stirred lab-scale reactor. These precipitation products were characterized using Scanning Electron Microscopy, Raman Spectroscopy, X-Ray Diffraction, and carbon coulometry to measure carbonate content. This analysis confirmed the presence of both Pi and CO3 in a bone-like, carbonate apatite. Although other technologies are being explored to recycle phosphorus from wastewater streams, this is the first indication that it may be possible to precipitate a carbonate apatite by mixing two waste streams, municipal waste water and CO2 (g), with cost-effective CaCO3.
19

Towards Circular Economy: Exploring states´ incentives for change

Andersson, Jonas January 2019 (has links)
This paper explores how policy makers want a transition towards circular economy to look like and what solutions they visualize, with a focus on the why(?) arguments. By analyzing the discourse in states official roadmaps towards circular economy, this study forms an understanding for what motivates a transition. The findings show that the possibilities for economic gains and the creation of new markets are the main purpose to change. In addition to that, whenever the survivability of humanity and the environment was arguments for a change, it in almost all cases came back to the economical outsets with such transition, how much money can be gained/saved.
20

The environment quality and economics growth in China-A literature review and discussion

Liu, Qianqian January 2012 (has links)
This theses presents a discussion on the symbiotic relationship between the economic development and environmental protection. The presentation is based upon an extensive literature overview with a strong focus on Chinese research publications.

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