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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.
331

Extended producer responsibility as a management practice for waste mattresses in British Columbia

Hume, Miles Grey 12 March 2014 (has links)
Development of stewardship programs for management of end-of-life mattresses (ELM) is a global challenge for governments. Metro Vancouver is the first Canadian regional government to ban mattresses at local landfills. The next step is for manufacturers and retailers to work with local governments in developing stewardship programs that successfully divert and recycle mattresses across British Columbia (BC). This thesis examines how mattress industry stakeholders in BC could effectively implement province wide mattress stewardship policy that will ensure maximum public participation and will be environmentally sound as well as cost effective. Research was conducted by way of a literature review, a case study approach of Metro Vancouver's mattress recycling bylaw and model, and exploratory interviews with BC stewardship program leaders, Sleep Country Canada, government waste management planners, and mattress recyclers.
332

Avfallsfraktioner i Sveriges hamnar / Garbage fractions in Swedish ports

Ljungqvist, Helena, Lönnqvist, Jonas January 2015 (has links)
Varje år ökar avfallsmängden och användningen av naturens resurser vilket gör att återvinning blir en viktig del för ett hållbart samhälle. Årligen dumpas mer än 6,4 miljoner ton plast i haven från fartyg. Den 1 januari 2013 skärptes regelverket MARPOL för att minska mängden avfall som slängs i havet. Mot denna bakgrund har syftet med studien varit att undersöka hur motivationen att sortera kan påverkas av antalet avfallsfraktioner i hamnarna. En kvalitativ metod med sju intervjuer har använts. Resultatet visar att antalet fraktioner inte är det viktigaste för att öka återvinningen. Studien visar också att det saknas en standard i hamnarna. Tillgänglighet, närhet och att det är enkelt att lämna avfallet framkommer som de viktigaste faktorerna. / Every year the amount of garbage and the use of natural resources increases which makes recycling an important subject for a sustainable society. Yearly more than 6,4 million tons of plastic is dumped into the oceans from ships. From the 1st of January 2013 MARPOL regulation got stricter to decrease the discharge of garbage into the sea. Against this background the purpose of this study has been to examine how the motivation to recycle can be effected of the number of garbage fractions in the ports. A qualitative method has been used and seven interviews were conducted. The result shows that the number of fractions is not the most important factor to increase recycling. The study also shows that there is no standard in the ports. Accessibility, proximity and that it is easy to carry out emerges as the main factors.
333

Material Flow and Stakeholder Analysis for a Transfer & Recycling Station in Gaborone, Botswana

Andersson, Emil January 2014 (has links)
Landfilling waste material is still one of the most common methods to take care of waste in a big part of the world. Gaborone, the capital of Botswana located in the southern part of Africa is no different in this way. The major part of all waste is landfilled in Gaborone and there is only a minor part of all collected material that is recycled. One solution that earlier studies suggest is to build a transfer and recycling station in the city of Gaborone that can contribute to a more sustainable waste management. This study aims to identify the major waste streams of recyclable waste and also the major stakeholders that are active in this area through an exploratory study involving interviews, a workshop and a survey. The result of this thesis can hopefully assist in the preparations for such a transfer station. The conclusions of this study are many and contains of both hard facts and also loose ends that can contribute to pursue further studies. The first important result is that all the waste collection companies transports everything they collects to a landfill and it is only recycling organizations that are working with collection and recycling in Gaborone. These recycling organizations are a few but smaller compared to the waste collection companies in collected amounts of material. Besides these collection organizations, Gaborone City Council, the local municipality works with collection of household waste and the collaboration between these three groups that operates in the same environment is very poor. All the interviewed stakeholders showed a positive interest in the transfer and recycling station but there is only a small part of the commercial business in Gaborone that believes in a more serious waste management than landfilling. Despite that one major shopping mall actually sort out recyclables and saves 30% in waste management costs thanks to that. Another issue is the prevailing cultural contradictions that is obvious among the organizations in Gaborone. The last two bigger issues is the tremendously dull political bureaucracy that is appearing in Botswana and also that voices are raised that corruption is great beneath the surface.
334

Development and Studies of the Processes Involved in Minor Enantiomer Recycling

Laurell Nash, Anna January 2014 (has links)
This thesis describes the development and rationalization of processes involved in a new methodology developed in our group, minor enantiomer recycling. The first part of the thesis addresses mechanistic studies of one of the reactions involved in minor enantiomer recycling, dual Lewis acid-Lewis base catalyzed acetylcyanation of aldehydes. The methodology uses a combination of a chiral titanium-salen  complex with a tertiary amine as a catalytic  system  in  the enantioselective  synthesis  of  O-acylated  cyanohydrins from aldehydes and ketonitriles. Mechanistic investigations revealed that the rate-determining step in the reaction changes, depending on the nature of the aldehyde that was used. It was also concluded that cyanohydrin is coordinated to the Lewis acid in the acylation step. The second part of the thesis deals with minor enantiomer recycling, a highly selective one-pot recycling system. In a first step the product is formed as a minor and a major enantiomer by asymmetric catalysis. Recycling of the minor enantiomer, by selective kinetic resolution, regenerates the starting material. Continuous addition of a second reagent, also involved in a coupled exergonic process, leads to an increase of both yield and enantiomeric excess. Recycling procedures for the synthesis of O-acylated and O-formylated cyanohydrins have been developed with high yield and high enantiomeric excess of the products. The study includes development of the systems, comparison to other methodologies in asymmetric catalysis, and attempts to understand the processes involved. / <p>QC 20141202</p>
335

The management of post-consumer plastics waste recycling in the UK

McDonald, Seonaidh January 1996 (has links)
This thesis examines the management of post-consumer plastics waste recycling in the UK. It brings together information and approaches from a number of disciplines in order to present a comprehensive view of the post-consumer plastics waste recycling industry and provide insight into participation issues. Two Scottish collection schemes are utilised as case studies throughout. The thesis summarises current practice in post-consumer plastics recycling and describes the processes associated with it. It also presents a summary of legislation relevant to plastics recycling in the UK, EC and US in particular. The thesis includes a quantitative survey of 500 members of the public that analyses their recycling behaviour and factors that affect motivation. It also looks at public perceptions of plastics. This is complemented by a qualitative study of plastics recyclers that examines recycling routines in more detail, and explores issues that affect the participation, and quality of donation, of individuals. The evaluation of post-consumer plastics recycling schemes is discussed, and models are developed in order to assessth eir financial viability. The lessons gained from this programme of research are then summarised in a policy framework.
336

Conversion of hardwoods to ethanol: design and economics of delignification and enzyme recycling

Paruchuri, Divya 25 August 2008 (has links)
The objective of this study was to investigate the possibility of recycling enzymes during saccharification of cellulose for the production of ethanol from woodchips. To make enzyme recycling feasible and economical when woodchips are processed for ethanol, the lignin in the wood is to be removed before the enzymes are added. Since enzymes constitute a major part of the input costs, second only to the feedstock, the ability to reuse the enzymes could lead to a considerable decrease in the production cost of ethanol. Tulip poplar woodchips were selected as the feedstock. Different delignification methods with recovery of byproducts were investigated. Alkali extraction, using dilute NaOH for the removal of lignin after steam pretreatment, was used as the base case against which all other processes were compared. Recovery of furfural and methanol, produced during the pretreatment of the woodchips, for sale as byproducts was one modification to the alkali extraction process that was investigated. The conversion of xylose to furfural and the recovery of the furfural as a byproduct was the third case explored. Solvent extraction using a 50:50 ethanol-water mixture instead of extraction with NaOH was the fourth case examined. Process flow sheets were then developed to recycle the enzymes during the hydrolysis and fermentation of this prehyrolyzed and delignified wood. Two reactor setup schemes were examined for enzyme recycling. One scheme involved a single train of reactors, with the whole pretreated slurry flowing from one reactor to the next, whereas, in the other scheme, the slurry was split among parallel trains of reactors. The activity loss of the enzymes was modeled such that a part of the enzymes entering the reactor lost all their activity. The loss of activity in multiple steps, with enzymes losing only some of their activity, was also modeled. Here the enzymes entering the reactor constituted a mixture with different activities instead of all the enzymes having the same activity like in the previous single step model. Recovering methanol and furfural reduced the minimum ethanol selling price. High temperature ethanol water pretreatment and lignin extraction reduced the minimum ethanol selling price compared to the base case of steam pretreatment followed by alkali extraction. Enzyme recycling also reduces the minimum ethanol selling price. The magnitude of the price reduction depends on the recycling scheme selected and the rate of enzyme deactivation, which has not been measured.
337

Recycling at home and away differences of recycling participation between residents and non-residents on two Northern Michigan islands /

Kidder, Jessica Lauren. January 2006 (has links)
Thesis (M.A.)--Michigan State University. Dept. of Geography, 2006. / Title from PDF t.p. (viewed on June 19, 2009) Includes bibliographical references (p. 54-56). Also issued in print.
338

Ultimate form of recycling : integrated landfill management: leachate recirculation, landfill gas utilization and landfill mining : are they applicable to Hong Kong? /

Hon, Siu-ming. January 1995 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1995. / Includes bibliographical references (leaves 107-112).
339

Waste management and its implications for environmental planning : a review of the waste management strategy for Hong Kong /

So, Wing-yeung. January 1994 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1994. / Includes bibliographical references (leaf 63-64).
340

The waste separation and recycling scheme in schools /

Tang, Hoi-wan. January 2001 (has links)
Thesis (M. Sc.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 60-62).

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