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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.
81

Udržitelnost systémů odpadového hospodářství / Waste management system sustainability

Bravený, Adam January 2014 (has links)
The thesis proposes a new approach to assess sustainability of waste management systems. In the first part current mixed municipal waste (MSW) management system of the Czech republic is reviewed and promising MSW treatment techniques are introduced. In the second part a summary of literature on Life Cycle Assessment (LCA) approach to assess sustainability of MSW systems is provided. A new sustainability assessment model is proposed by implementing LCA to a current tool called NERUDA used to optimize waste management costing. It is demonstrated how to connect these two concepts in order to aquire a powerful tool for sustainability assessment.
82

Identifikace podobných řešení při stochastické simulaci v oblasti odpadového hospodářství / Similar solution identification in the field of stochastic simulation related to waste management

Gal, Pavel January 2015 (has links)
The Master’s thesis deals with the issue of collecting mixed municipal waste from producers to a~waste-to-energy or landfills. The initial chapters are aimed to waste legislation and transportation of the waste by road freight transport across Europe. The objective is to collect the data, that are required for calculation in tool NERUDA. The next part describes the cluster analysis and different approaches in it. The selected methods of cluster analysis are apllied to the logistic task in the final chapters. The cluster analysis is considered from different aspects. The results are visualized using the software ArcGIS.
83

Waste of Opportunities - A Holistic Study of the Current Situation of Municipal Waste Management in Shandong Province, China

Ambell, Christine, Xu, Yixuan January 2009 (has links)
China’s growth and development have opened the door to a new world. Shandong province’s 90 million inhabitants are entering into a consumption society and the waste stream from households, restaurants and commercials has become a challenge. So far, the waste has mostly been burned in backyards, thrown into rivers, put on open dumps or taken to landfills. The environmental consequence is strong. This study was carried out in Shandong province and presents the current situation of the municipal waste management. The result of the study is organised into social, economical, technical and environmental parameters. It mostly covers the years 2006 to 2010. In the discussion, the strength, weakness, opportunities, and threats to the management are analysed, which gives an overview of the complex situation. The final conclusion is that there are a lot of opportunities in developing municipal solid waste management in Shandong province since the work and planning is new and economy is good. Threats are for example a larger waste stream. The municipal waste management has some strengths, such as a lot of projects going on, but also a lot of weakness for instance implementation of the regulations and laws. / Kinas starka tillväxt håller på att skapa ett konsumtionssamhälle som påminner om det västerländska. Med högre konsumtion och starkare ekonomi växer avfallsmängderna snabbt. I Shandong provinsen finns mer än 90 miljoner invånare som varje dag gör sig av med 0,5 – 1,5 kg sopor. Det är en utmaning för samhällsplanerana och ingenjörerna att ta hand om dessa volymer. Hittills har det mesta av avfallet bränts på bakgårdar, kastas i vattendrag, ut i naturen eller lagts på deponi. Miljöskadorna är stora. Denna studie beskriver avfallshanteringens situtation i Shandong provinsen. Faktan är uppdelad utefter sociala, ekonomiska, tekniska och ekologiska parametrar. Studien täcker åren 2006 till 2010. Olika avfallsanläggningar och konstruktioner besöktes, utländsk litterlatur användes och en handledare från ett kinesiskt provinskonstruktionsföretag bidrog med information och data. Studien är delvis dokumenterad med foton. I diskussionen analysers styrkor, svagheter, möjligheter och hot med avfallshanteringen för överblick av situationen. I slutsatsen framgår det att det finns många möjligheter i utvecklingen av ett avfallshanteringssystem eftersom det är nytt, flexibelt och ekonomin är god. Det finns även hårda miljö och säkerheteslagar som påminner om EUs och USAs. Till hoten räknas stora avfallsvolymer som kan vara svårkontrollerade, samt att alldeles för hårda lagar kan hindra nya innovationer och teknik. Styrkor som finns är att fler än 111 stycken projekt är på gång, och att kunskap finns på högre ledningsnivå. Svageheterna är dålig implementering av lagar samt dålig kunskap på lägre nivå. Eftersom avfallhanteringen är i ett initierande stadie så kan de val som görs nu påverka på väldigt långt sikt.
84

Anaerobic digestion in continuous stirred tank reactors and plug flow reactors: : Comparison study concerning process performance / Anaerob rötning i kontinuerligt omrörda tankreaktorer och pluggflödesreaktorer: : Jämförelsestudie avseende processprestanda

Kocak, Zeko January 2022 (has links)
Användningen av kommunalt avfall för att producera förnybar energi, huvudsaklig biogas, uppfyller 8 av Sveriges 16 miljökvalitetsmål. Två typer av rötningsprocesser som används är kontinuerligt omrörda tankreaktorer (CSTR) och pluggflödesreaktorer (PFR). Rapportens syfte är att direkt jämföra de två reaktorkonfigurationerna, PFR och CSTR, med samma substratblandning. Båda reaktortyperna drevs med samma belastning (5,2 g VS/L dag), hydraulisk retentionstid (30 dagar) och driftstemperatur (520C). Två PFR-reaktorer drevs med återcirkulation av rötrester. Under projektets gång mättes olika parametrar, vilka var: pH, total gasvolym och gassammansättning, FOS/TAC (organiska syror/alkalinitet), flyktiga fettsyror (VFA), ammonium-kvävekoncentration och TS (torrsubstanshalt) och VS (organiska ämnen). Studieresultatet var uppdelat i två sektioner. Avsnitt 1 sammanfattar uppstartsperioden, där alla tre CSTR (D1-R, D2-NR och C1-NR) kördes i icke-återcirkulerande läge. Uppstartsperioden gjordes för att säkerställa reaktorernas stabilitet och det gällde att uppnå en liknande baslinje för detektion. Inom studien accepterades avvikelser för baslinjen inom intervallet 0-5%. För uppstartsperioden varierade den specifika metanproduktionen med 2 % mellan D1-NR och D2-R, D1-R och C1-NR med 6 %, och D2-NR och C1-NR med 8 %. För ammoniak-koncentrationen var skillnaden mellan D1-R och D2-NR 2 % och mellan D1-R och C1-NR 9 %, mellan D2-NR och C1-NR, 7%. Med dessa variationer togs beslutet att utesluta reaktor C1-NR från den experimentella perioden för projektet. Avsnitt 2 jämför PFR och CSTR återcirkulerat/icke återcirkulerat läge. En CSTR drevs med 30 % återcirkulation av rötrest och en CSTR drevs i icke-återcirkulationsläge. Att jämföra PFR och CSTR återcirkulerat/icke återcirkulerat läge visade att PFR:erna övervann båda CSTR:erna när det gäller den specifika metanproduktionen. Där PFR producerade 395±93 NL/KgVS och 372±42 (N)L/KgVS CSTR med återcirkulation 280±10 (N)L/KgVS och den icke-återcirkulerade CSTR producerade 250±7 (N)L/KgVS. NH4+-N-nivåerna mellan PFR och CSTR visade en skillnad på 1 g/L, där PFR var den med högre NH4+-N (2,53±0,39 g/L för PFR-A och 2,73±0,43 g/L för PFR-T). En av skillnaderna mellan de återcirkulerade och de icke-återcirkulerade CSTR:erna var VFA-koncentrationen. VFA-koncentrationen i de återcirkulerade var 1,05±0,90 g/L och 0,43±0,25 g/L i de icke-återcirkulerade. VFA-koncentrationen för PFR var i genomsnitt 0,28±0,12 g/L och 0,40 ±0,16 g/L. Graden av nedbrytning i CSTRs var 90-91%, och 63-65% i PFR. Den är möjligen felberäknad och visar en inkonsekvens mellan reaktorernas prestanda och specifik metanproduktion. / The use of municipal waste to produce renewable energy, in the form of biogas, fulfils eight of Sweden's sixteen environmental quality objectives. The most common technology to produce biogas is anaerobic digestion (AD). Two common types of AD processes are continuously stirred reactors (CSTR) and plug flow reactors (PFR). The thesis aims at directly comparing the two reactor configurations using the same substrate mix. For this, two PFRs (PFR-T and PFR-A) and three CSTRs (D1-R, D2-NR and C1-NR) were setup. All reactors were operated at the same organic loading rate (5.2 g VS/L-day), hydraulic retention time (30 days) and operational temperature (52°C). During the project, various parameters were measured to evaluate the reactor performance, such as pH, total gas volume and gas composition, FOS/TAC (organic acids/alkalinity), volatile fatty acids (VFA), ammonium-nitrogen concentration, and solid and volatile solid of digestate.   The study result was divided into two sections. Section 1 summarises the start-up period (42 days), where the CSTRs and the PFRs were operated under non-recirculation mode. The start-up period was done to ensure the stability of the reactors and was concerned with achieving a similar baseline for performance. For the start-up period, the specific methane production between D1-R and D2-NR varied by 2% while the variation between C1-NR and D2-NR was 8%. Likewise, for the ammonia concentration, the difference between D1-R and D2-NR was 2%, while C1-NR differed by 9% from D2-NR. Based on these findings, the decision was taken to exclude reactor C1-NR from the experimental period of the project.  Section 2 compares the PFR and CSTR. One CSTR was operated with 30% recirculation of digest, while the other CSTR was operated in non-recirculation mode. The two PFRs were operated with recirculation of digestate. The experiments showed that the PFRs outperformed both CSTRs regarding the specific methane production. The PFRs produced 395±93 (N)L/kg-VS and 372±42 (N)L/kg-VS. In contrast, the CSTR with recirculation reached 280±10 (N)L/kg-VS and the non-recirculated CSTR produced 250±7 (N)L/kg-VS. The NH4+-N levels for the PFRs and CSTRs showed a 1 g/L difference, with a higher value for the PFRs (2.53±0.39 g/L for PFR-A, and 2.73±0.43 g/L for PFR-T). One of the significant differences between the recirculated and the non-recirculated CSTRs was the VFA concentration. The VFA concentration in the recirculated and non-recirculated reactor was 1.05±0.90 g/L and 0.43±0.25 g/L, respectively. The VFA concentration for the two PFRs was on average 0.28±0.12 g/L and 0.40 ±0.16 g/L. The degree of degradation in the CSTRs was 90-91% compared to 63-65% in the PFRs. The degree of degradation is possibly miscalculated and shows an inconsistency between the reactor performance in terms of specific methane production.
85

Land pollution and population density : the case of Kwekwe City residential areas, Zimbabwe

Chatsiwa, Jaison 02 1900 (has links)
In most developing countries, the problem of inefficient municipal solid waste management (MSWM) is endemic. The problem is manifested by heaps of uncollected solid waste found on open areas and by the street sides. This dissertation examines the relationship between land pollution and population density resulting from solid waste generation in the City of Kwekwe in Zimbabwe. Questionnaires and interviews were conducted to 375 randomly selected households in low, medium and high density residential suburbs. The household survey was triangulated with field observations, key informant interviews and secondary data sources. The average household size in high, medium and low density residential areas was 11, 8 and 5 people respectively. The study revealed that the amount and composition of solid waste generated varied according to household size, income and education levels of residents. The higher the population density, the more the solid waste produced. However, waste generated was not carried to the dumpsites for disposal. Also the higher the income, the higher the amount of solid waste produced, although residents with high income were able to ferry their wastes to the dumpsites hence less land pollution. The solid waste generation rate in high density areas was 0.04 kg/capita day, in medium density areas was 0.35 kg/capita/day and in low density areas were 0.84 kg/capita/day. It was also observed that among high income earners, the educated people produced more waste than low income earners. However, the low income earners and the less educated people could not take care of their environment to limit roadside and open space littering. However, lack of public awareness coupled with inefficient and ad hoc waste management system continue make provision of effective solid waste management services illusive. Based on the research findings, it is suggested sound environmental stewardship amongst residents will limit land pollution in the city of Kwekwe. / Environmental Sciences / M.A. (Environmental Management)
86

Gevaarlike afval in huishoudelike afval : 'n gevallestudie / Rianca Kruis

Kruis, Rianca January 2010 (has links)
Rapid population growth and urbanisation has resulted in a drastic increase in the volume of waste produced by the World populace. The resulting pressure on the country’s somewhat underdeveloped waste management infrastructure emphasizes the need for waste management solutions which balance environmental protection with economic sustainability. Waste is seen as an unwanted or surplus by-product, emission or residue of any process or activity which has been discarded, accumulated or stored for the purpose of discarding or future processing. Hazardous waste is waste that may, by circumstance of use, quantity, concentration or inherent physical, chemical or infectious characteristics, cause ill-health or an increased mortality rate in humans, fauna and/or flora. General waste on the other hand, is waste that does not pose an immediate threat to human health or the environment. Currently household waste is considered general waste even though it may contain hazardous components such as fluorescent tubes and/or other household chemicals. Promulgation of NEM: WA (no 59 of 2008) provides instruments for the implementation of the steps taken by the Department of Environmental Affairs to improve waste management in South Africa. Successful implementation and enforcement of the act will place the country at the forefront of progressive international standards in waste management. One of South Africa’s largest environmental and waste management challenges remains the presence of historical, hazardous waste landfill sites. Characterisation of the dangers that these sites pose to the environment is providing extremely difficult and expensive, as is the ongoing maintenance and management of these facilities – placing economic strain on national municipalities. This study was done in two phases. The first related to the hazardous waste components of household waste that is being dumped at landfill site and the methods of classification, handling and dumping of hazardous waste have been investigated. All the legislation was taken into consideration to see if the landfill sites comply with the latest legislation. The second phase was a comparison between three landfill sites. The management, work activities and general appearance of the sites have been compared internally. Then a comparison have been done between the following landfill sites Kwaggasrand landfill site in Tshwane, Weltevreden landfill site in Brakpan and an ideal landfill site developed in accordance with the Minimum Requirements documents published by of DEAT in 1998. / Thesis (M.Sc. (Geography and Environmental Studies))--North-West University, Potchefstroom Campus, 2011.
87

Gevaarlike afval in huishoudelike afval : 'n gevallestudie / Rianca Kruis

Kruis, Rianca January 2010 (has links)
Rapid population growth and urbanisation has resulted in a drastic increase in the volume of waste produced by the World populace. The resulting pressure on the country’s somewhat underdeveloped waste management infrastructure emphasizes the need for waste management solutions which balance environmental protection with economic sustainability. Waste is seen as an unwanted or surplus by-product, emission or residue of any process or activity which has been discarded, accumulated or stored for the purpose of discarding or future processing. Hazardous waste is waste that may, by circumstance of use, quantity, concentration or inherent physical, chemical or infectious characteristics, cause ill-health or an increased mortality rate in humans, fauna and/or flora. General waste on the other hand, is waste that does not pose an immediate threat to human health or the environment. Currently household waste is considered general waste even though it may contain hazardous components such as fluorescent tubes and/or other household chemicals. Promulgation of NEM: WA (no 59 of 2008) provides instruments for the implementation of the steps taken by the Department of Environmental Affairs to improve waste management in South Africa. Successful implementation and enforcement of the act will place the country at the forefront of progressive international standards in waste management. One of South Africa’s largest environmental and waste management challenges remains the presence of historical, hazardous waste landfill sites. Characterisation of the dangers that these sites pose to the environment is providing extremely difficult and expensive, as is the ongoing maintenance and management of these facilities – placing economic strain on national municipalities. This study was done in two phases. The first related to the hazardous waste components of household waste that is being dumped at landfill site and the methods of classification, handling and dumping of hazardous waste have been investigated. All the legislation was taken into consideration to see if the landfill sites comply with the latest legislation. The second phase was a comparison between three landfill sites. The management, work activities and general appearance of the sites have been compared internally. Then a comparison have been done between the following landfill sites Kwaggasrand landfill site in Tshwane, Weltevreden landfill site in Brakpan and an ideal landfill site developed in accordance with the Minimum Requirements documents published by of DEAT in 1998. / Thesis (M.Sc. (Geography and Environmental Studies))--North-West University, Potchefstroom Campus, 2011.
88

Land pollution and population density : the case of Kwekwe City residential areas, Zimbabwe

Chatsiwa, Jaison 02 1900 (has links)
In most developing countries, the problem of inefficient municipal solid waste management (MSWM) is endemic. The problem is manifested by heaps of uncollected solid waste found on open areas and by the street sides. This dissertation examines the relationship between land pollution and population density resulting from solid waste generation in the City of Kwekwe in Zimbabwe. Questionnaires and interviews were conducted to 375 randomly selected households in low, medium and high density residential suburbs. The household survey was triangulated with field observations, key informant interviews and secondary data sources. The average household size in high, medium and low density residential areas was 11, 8 and 5 people respectively. The study revealed that the amount and composition of solid waste generated varied according to household size, income and education levels of residents. The higher the population density, the more the solid waste produced. However, waste generated was not carried to the dumpsites for disposal. Also the higher the income, the higher the amount of solid waste produced, although residents with high income were able to ferry their wastes to the dumpsites hence less land pollution. The solid waste generation rate in high density areas was 0.04 kg/capita day, in medium density areas was 0.35 kg/capita/day and in low density areas were 0.84 kg/capita/day. It was also observed that among high income earners, the educated people produced more waste than low income earners. However, the low income earners and the less educated people could not take care of their environment to limit roadside and open space littering. However, lack of public awareness coupled with inefficient and ad hoc waste management system continue make provision of effective solid waste management services illusive. Based on the research findings, it is suggested sound environmental stewardship amongst residents will limit land pollution in the city of Kwekwe. / Environmental Sciences / M.A. (Environmental Management)
89

Vers une gouvernance territoriale de l'environnement ? : analyse comparée des politiques départementales de gestion de l'eau destinée à la consommation humaine et des déchets municipaux / Towards a territorial governance of the environment ? : an analysis of the policies of drinking water and municipal waste management at the "départemental" level of the French institutions

Caillaud, Kévin 19 September 2013 (has links)
Quarante ans de politiques publiques d’environnement ont profondément modifié la gestion de l’eau et des déchets. Beaucoup de choses ont changé : le référentiel gestionnaire n’est plus le même, la législation s’est renforcée, les enjeux territoriaux se sont recomposés, les modalités et l’échelle d’intervention publique ont été remodelées… En un mot, l’action publique territoriale s’est recomposée. Progressivement, les acteurs territoriaux ont inventé de nouvelles formes d’organisation, eu égard aux conditions et aux problématiques spécifiques de leurs territoires. Quelle(s) forme(s) ces recompositions peuvent-elles prendre ? Et selon quelle(s) trajectoire(s) ? Existe-t-il des invariants ? Qui pilote ces dynamiques territoriales et quelle place occupent les collectivités ? L’objectif de la thèse est de mettre en lumière l’existence d’une variété de formes d’organisation territoriale dédiées à la gestion de l’eau potable et des déchets municipaux, à partir d’une entrée « services publics ». Par le biais de monographies départementales, la thèse met à l’épreuve de la réalité du terrain les résultats d’une importante revue de littérature. Cela permet ainsi de mettre en exergue la force des coalitions d’acteurs et le jeu structurant entre Conseils Généraux et pôles urbains dans ces trajectoires de recomposition, ou encore l’existence d’un phénomène d’hybridation des modes de régulation influençant les trajectoires départementales. Enfin, en croisant la littérature spécifique à l’action publique et la grille d’analyse développée, la thèse propose de contribuer au lexique analytique de ce domaine d’étude. / After forty years of environmental public policies, drinking water and municipal waste management changed. For instance, the paradigm of environmental sectors management evolved, the legislation strengthened and the emergence of new environmental issues changed the territorial organizations… Step by step, territorial actors created new forms of organization, in regard to the special issues of their territories. What kind of forms these evolutions can take ? What are the territorial trajectories ? Can we observe some straightness ? Who governs these dynamics and what is the role of territorial public institutions ? The thesis shows the existence of different forms of territorial organizations at the “départemental” level of the French institutions, dealing with public services involved to the drinking water and municipal waste management. With four monographs, the thesis shows the power of advocacy coalitions and urban cities in the trajectories of evolution. These appear also oriented by different regulation’s hybridization phenomena. With all these results, the author proposes at last to contribute to the analysis's lexicon of this domain of research.
90

Solid waste reduction management with special reference to developing countries

Human, Etienne Hugo 30 November 2005 (has links)
Sustainable development and the Triple Bottom Line integrated sustainability concept focus on the choices between the imperatives of economic efficiency, social development and environmental sustainability. Corporate governance is being imposed by stakeholders and corporate social responsibility is indicated as being the most important socio-environmental demand being made on contemporary leaders. The influence of idealism and realism on, and the reasons for failure of, solid waste reduction projects in terms of sustainability is the foundation of the theories postulated in this research. It is the objective of this research to identify the motivational factors, with special reference to developing countries, of social capital, including management processes leadership and people management, that will augment solid waste reduction projects that are lethargic at starting, or deteriorating, to achieve sustainability. The methodology is to review the literature available to identify the augmenting (motivational) factors, and use analytical philosophical and empirical research to test formulated constructs using hypotheses. The criterion for the research sample is to obtain the opinions of environmental specialists in South Africa using a questionnaire. The technique employed is multivariate data analysis to identify the type of interdependent relationships, including cluster and multidimensional scaling analyses. Hypothesis testing, in this research, leads to the conclusion that additional motivational factors are needed to support the economic imperatives to make the process sustainable. `Reality' is statistically significantly different to `idealistic'. The inference is that for solid waste reduction projects to succeed leaders from government and the private sector are required, through the use of legislation and taking into consideration the value of waste, to instil economic incentives. According to this research, personal values and belief systems have little to contribute to the process of sustainability. The outcome of this research provides a strategy-benchmarking-model that leaders can use to target and prioritise their efforts in respect of achieving success with waste projects. The contribution it makes to the knowledge base of the subject and responsible leadership is contained in its summation of the augmenting factors required, their relative importance, and the lessening of the complexity of approach to these projects. / Graduate School of Business Leadership / D.B.L.

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