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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.
21

Development of the magnesia process for the treatment of highly alkaline textile wastes

Pierce, James Craven 12 1900 (has links)
No description available.
22

Aspects of biological treatment of oil refinery and petrochemical waste water

Agathos, Spyridon Nicholas January 1976 (has links)
No description available.
23

Modelling and simulation of paper recycling processes

Promboon, Warot. January 1996 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1996. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 106-108).
24

Wet air and related metal ion-catalysed oxidation reactions of methylpyridines

Morris, Jacqueline January 1995 (has links)
The Wet Air Oxidation process has considerable attractions for the disposal of toxic organic wastes. In this thesis, a fundamental study is made of the mechanism of oxidation under wet air and related conditions of a series of well-defined substances known to occur as components of industrial wastes, and which are known to present difficulties in the Wet Air Oxidation process. In the initial stages, the oxidation of a series of simple alkylpyridines, namely 2-, 3-, and 4-methylpyridines, has been studied under simulated Wet Air Oxidation plant conditions in a laboratory autoclave operating at 250°C and 250 atmospheres. The progress of the oxidation was followed by withdrawing samples at intervals and subjecting these to chromatographic analysis, using Gas Chromatography-Mass Spectrometry and High Performance Liquid Chromatography, so as to establish the nature of the oxidation products. In the autoclave oxidation of 2-, and 4-methylpyridine, a wide range of oxidation products was detected, including a number of compounds which appeared to be derived from the reactions of pyridylalkyl radicals formed from the parent substance, implying that a free radical mechanism was occurring under Wet Air Oxidation conditions. Under these conditions, 3-methylpyridine appeared to be more resistant to oxidation, the only significant oxidation product being the related aldehyde. The literature suggests that the formation of the hydroxyl radical (OH) under Wet Air Oxidation conditions may be responsible for the initiation of the above reactions, and thus the possibility of catalysis of the above systems by reagents known to generate hydroxyl radicals has been explored. The literature suggests that Fenton's reagent, which is a mixture of iron(ll) and hydrogen peroxide, provides a source of hydroxyl radicals. Thus, the oxidation of the methylpyridines using Fenton's reagent at ambient temperature and atmospheric pressure was carried out and it was also used as a catalyst in the autoclave oxidation reactions. The effectiveness of other metal ion/hydrogen peroxide mixtures was explored, e.g. involving iron(lll), copper(ll), copper(l), titanium(lll), and vanadium(IV), as there is considerable evidence from the literature of their involvement in oxidation chemistry. In all of the oxidation reactions investigated, both under autoclave conditions, and at room temperature, evidence of destructive oxidation of the heteroaromatic ring has been gained for all three methylpyridines. However, in addition to ring destruction products, a range of intermediate oxidation products was observed and similarities were found between those products formed in the autoclave and those reactions carried out in the laboratory. However, recent literature has questioned the formation of hydroxyl radicals by Fenton and related reagents, and so the Fenton catalysed oxidation of each of the methylpyridines was explored further. This was done by the incorporation of appropriate radical trapping agents and complexing agents such as 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) and ethylenediaminetetraacetic acid (EDTA) respectively. In each of the oxidation reactions studied, attempts have been made to identify as many as possible of the products observed by comparison with known substances. However, it has been necessary to develop procedures for the preparation of some of these compounds, notably a range of dimeric structures derived from the simple alkylpyridines, e.g. dipyridylethenes, dipyridylethanes, and dipyridylmethanes.
25

Aspects of biological treatment of oil refinery and petrochemical waste water

Agathos, Spyridon Nicholas January 1976 (has links)
No description available.
26

Exploratory Study of Waste Generation and Waste Minimization in Sweden

Kuslyaykina, Dina January 2013 (has links)
The current thesis presents an exploratory study on municipal solid waste generation and minimization in Sweden, with a focus on their connection to basic socio-economic parameters. The fundamental goal of the study is to investigate into correlations and interdependencies between waste generation, waste minimization and basic socio-economic characteristics on municipal level, and to search for models for explanation of waste management parameters through socio-economic factors. Theoretical background involves reasoning on the role of municipal waste management in sustainable development, and extensive analysis of framework, legislation and organization of municipal solid waste management in Sweden. Practical part presents correlation analysis of data, which proved that socio-economic parameters do not explain differences in waste management performance of Swedish municipalities; however they are closely connected to differences between municipalities in aspect of presence of waste-related data.
27

Legislative support for waste reduction initiatives /

Liu, Wai-leung. January 1997 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 60-67).
28

Avfallsprojekt Östersunds kommun : Avfallshantering och avfallsminskning i livsmedelsverksamheter

Zakrisson, Anna January 2018 (has links)
Waste is high up on the list when evaluations been done over the seriousness, size and trend of environmental aspects in the municipality of Östersund, Sweden. Environmental inspections are of need to reduce waste and reach a higher extent of waste separation. The board of environment and society have given the inspection authority the assignment to carry out a waste treatment project to evaluate if food operations fulfill the legislation demands on how to handle their waste in purpose of improving waste separation and reducing food waste. The environmental legislation in Sweden obliges everyone to prevent that people’s health and the environment gets negatively affected by the activities done. The legislation also obliges everyone to decrease, reuse and recycle waste. 29 food operations, who had the highest amount of registered food containers, have been inspected and interviewed with a questioning form and brochures with information and suggestions on how to separate waste and decrease food waste have been given out. Only two operations deviated from the legislation. There were ten operations that hade a complete separation of waste. 21 operations believed that the waste handling could improve and 13 operations where already working with reducing the amount of waste. All operations were working with reducing food waste and wanted to be able to minimize it even more. The outcome was positive with willingness to improve. But the awareness of legislation was low and the knowledge of why work is needed for the environment must get higher.
29

Investigation and development of a framework for medical waste management

Alhadlaq, Abdullah Abdulaziz January 2014 (has links)
The Kingdom of Saudi Arabia is the largest country in the golf states and one of the richest oil producing countries. Saudi population is nearly 27million; in addition, Saudi Arabia receives millions of people from around the world for Islamic pilgrimages. Moreover, Saudi is hosting hundreds of thousands of international professionals and labourers. Hence, the country infrastructure and services have been in the top agenda to be modernized in order to cope with new demand for better quality of life for a rich country. The healthcare sector is one of the key sectors which requires a special on going attention, particularly medically generated waste. Therefore, this research work has been conducted to investigate the status of medical waste management in the capital city; Riyadh. The prime aim of this research work is to propose a strategic framework which can be used as a roadmap for the different stakeholders. This will contribute to the enforcement of better handling and treatment of medical waste and more importantly prevent and control the spread of diseases or harm might be caused by poor handling of medical waste. The aim of the research has been achieved through; the critical review and analysis of the relevant literature, which has revealed the noticeable gap and lack of scientific studies of the proposed field. Appropriately, the findings of the research has contributed to filling the gap of the knowledge as well as serving as a milestone for further research work in this very important field. By surveying Riyadh’s hospitals and other national and international reports has. This allowed the presentation of the facts and indications of the current status of medical waste in Riyadh City. To obtain in-depth knowledge and gather the important findings concerning the medical waste management, focused; interviews of different medical professionals from various hospitals were conducted. This research has revealed more important factors that need to be addressed. These findings were used to propose the framework, which has been formed to enable resolving the challenges of the integration, of the awareness element though Islamic principles, within the Saudi system. The proposed framework has been evaluated by committee of medical professionals and has been accepted as good roadmap and appropriate solution that address the main aim of this research work. Finally, the research work is just a step towards the establishment of a proper biomedical waste management system in the Kingdom of Saudi Arabia. Some recommendations for future implementation are suggested at the end of this thesis.
30

Optimal Recovery of Resources: a Case Study of Wood Waste in the Greater Sydney Region

Warnken, Matthew January 2004 (has links)
In present day society there is an artificial dichotomy between wastes and resources that is perhaps best summed up by the Western Sydney Waste Board slogan 'there is no such thing as waste � only resources in the wrong place and at the wrong time'. Waste management was originally driven by managing the health consequences of wrong time/place materials. This has changed and the significant driver is now the sustainable utilisation of resources, that is, trying to optimally recover as resources (right time/place) those materials that present as wastes requiring management. However, it is not acceptable to justify a resource recovery option purely on the basis that it is diverting material away from landfill. Preferences are emerging for recovery activities that maximise the resource value of a material according to techno-economic, environmental and socio-political criteria; collectively known as the criteria of sustainability. The people and organisations articulating these preferences include owners/operators of resource recovery centres, proponents of alternative waste management technologies, waste planners and managers at both a state and local government level and environmental NGOs representing community interests, in addition to the generators of waste at a domestic, commercial and industrial, and construction and demolition level. It is therefore important to be able to answer the question of 'what is the optimal or most sustainable resource recovery option for materials presenting as waste to landfill in the Greater Sydney Region?' The point of departure for this thesis is twofold. Firstly, that optimal resource recovery options (also known as alternative waste management technologies) can be identified by understanding the context and system drivers and constraints within the system of waste generation and utilisation, by modelling the system using industrial ecology (specifically Materials Flux Analysis) and by using the technology assessment framework developed by the NSW Alternative Waste Management Technologies and Practices Inquiry to evaluate the available options. Secondly, that should the assessment framework from the NSW Inquiry prove to be unsuitable as a framework for evaluation, then an improved and refined assessment framework can be constructed in order to identify optimal resource recovery options and that this process can be successfully demonstrated using wood waste as a case study. The context of waste as an issue has shifted from local government control (pre-1970s) to state government control through the Department of Environment and Conservation. This transition followed experiments with organisations such as the NSW Waste Boards and Resource NSW, in addition to state targets such as a 60% reduction of waste to landfill by the year 2000. In addition to this backdrop of change from a government administrative perspective, there are also a suite of often conflicting drivers and constraints influencing the process of resource recovery. For example, sustainable development is a public policy driver for the integration of environmental and societal concerns, but can also constrain new innovation if competing 'status quo' utilisation options are not subject to the same scrutiny. Similarly, legislation acts as a constraint to resource recovery options by establishing license conditions, prohibiting some energy recovery options and setting recovery criteria; however legislation also acts as a driver for resource recovery options that generate renewable electricity or act to reduce greenhouse gas emissions. Other drivers and constraints include social, technical and economic issues and concerns in addition to environmental impacts such as emissions to air, land and water. Industrial ecology is a model for viewing system components as part of a dependent and interrelated greater whole. Within the context of Industrial Ecology, waste is a by-product of manufacture available as a beneficial input into other processes. Using Materials Flux Analysis as a tool to build a model of waste generation and utilisation, elements within the system are presented as a series of stocks (sources), technology interventions (transformation flows) and sinks (markets). The stocks or sources of materials for resource recovery are categorised as Municipal Solid (MSW), Commercial and Industrial (C&I) or Construction and Demolition (C&D) wastes. Approximately seven million tonnes of waste is generated in the Greater Sydney Region (nearly two and a half million tonnes of materials recovered for recycling and four and a half million tonnes of materials disposed of to landfill). The purpose of technology intervention is to transform the material into a product that is suited to the end market (sink). Markets are grouped according to reuse (same function and form), direct recycling (same supply chain), indirect recycling (different supply chain) and energy recovery (either as process heat, electricity or co-generation, a combination of the two). Landfill is also a potential sink for materials and in this sense can be thought of as a negative value market. The Alternative Waste Management Technologies and Practices Inquiry provided an assessment framework for resource recovery technologies. Each technology was measured and compared against 16 evaluation criteria, resulting in a score out of one hundred. Material sorting scored the highest (81.5), incineration the lowest (50.8) with most of the biological technologies performing �well� (64.6 � 71.7) and with the landfill technologies performing 'moderately well' (60.4 - 61.4). The positive features of the Inquiry included the overview of alternative resource recovery technologies, waste generation and other issues pertinent to decision making and resource recovery. The negatives of the Inquiry arise from the inadequacies of the assessment framework, which lacked technology options, system boundary definition and requisite evaluation criteria in addition to inconsistencies in scoring approaches. By undertaking a sensitivity analysis on the Inquiry�s results, it is shown that rank order reversal results from the allocation of weightings. The improved and refined assessment framework, constructed to overcome identified inadequacies of the Inquiry�s approach, focussed on clearly identifying the problem to be addressed and the primary decision maker involved in the process; ensuring that appropriate options for evaluation were included; defining the system boundary for the assessment; selecting necessary evaluation criteria; adopting a more sophisticated system for scoring; and using a sensitivity analysis to validate the results of the resource recovery option evaluation. Wood waste was used as a case study for this second assessment methodology. Wood waste refers to the end-of-life products, failed products, offcuts, shavings and sawdust from all timber products. Approximately 350,000 tonnes of wood waste are disposed of to landfill each year. This comprises untreated timber (hard wood and soft wood), engineered timber products (particleboard, medium density fibreboard and plywood) and treated timber (predominately copper chrome arsenic). Eight wood resource recovery options are selected for evaluation within the Greater Sydney Region with a different approach to scoring that has the advantage of 'scaling up' the best performers within each attribute (highest score) while 'scaling down' the worst performers (no score). Under this evaluation, an on-site purpose built energy facility is the most preferred option with particleboard manufacture the least preferred option. A sensitivity analysis of the results reveals that the scores of each technology option are sensitive to the weightings of the decision maker. When the change in rankings is examined, it is identified that two eight wood recovery options undergo a large rank reversal. A critique of the results of the wood evaluation reveals five major flaws. Firstly the evaluation produces non-highest resource value results that are non-intuitive (and arguably misleading), for example the poor performance of reuse and particleboard against energy generation options. Secondly, the recording of a single summary score for each recovery option hides unacceptable performance levels in some criteria. For example, the top scorer of Primary Energy On-site hides the fact that such an option is likely to have no political desirability (likely public opposition to 'incineration' within the Sydney air-shed), calling into question its ability to be implemented as a solution. Thirdly there is a reliance on judgement for the scoring of options and weighting of preferences, calling into doubt the accuracy of scores. Fourthly, the rankings of recovery options by the assessment framework are sensitive to the allocation of weightings. Finally and most importantly, the refined evaluation approach suffers from the 'discrete option syndrome', the scoring of each recovery option in isolation with no ability to look at integrated systems with joint recovery options. This is pinpointed as a fundamental flaw in the process of both the Inquiry and the wood evaluation. This leads to the conclusion that the founding assertions of this thesis were false. That is to say that the assessment framework developed by the NSW Alternative Waste Management Technologies and Practices Inquiry is not suitable for use in evaluating resource recovery options. Furthermore a refined assessment framework based on this approach is also unable to identify optimal resource recovery options as demonstrated using wood waste as a case study. The results of this research points to the overall conclusion that any discrete option evaluation and assessment for resource recovery technologies that results in a single summary score for each option will be fundamentally flawed, providing no value in determining optimal resource recovery solutions for the Greater Sydney Region. A systems approach is suggested as an alternative method for the evaluation of optimal resource recovery, the starting point of which is to ask 'what is the highest resource value of the components in the material stream under consideration and how could a network of infrastructure be designed in order to allow materials to flow to their highest resource value use?' A feature of such an integrated approach is a focus on the materials composition of recovered resources, as opposed to recovery technologies, resulting in a 'fit for purpose' as opposed to a 'forced fit' style of resource recovery. It is recommended that further research and public policy efforts be made in logistics planning across the Greater Sydney Region (as opposed to a regional or local government area) in order to create network opportunities for integrated flows of materials to move toward their highest resource value.

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