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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.
531

Process optimization and properties of protein concentrates from brewers' spent grain

Diptee, Rosemarie January 1989 (has links)
No description available.
532

A FREILP Approach for Long-Term Planning of MSW Management System in HRM, Canada

Wenwen, Pei 26 August 2011 (has links)
The municipal solid waste (MSW) management system is consisted of planning, development, execution of capital works, and so on. Too many factors in the system make the decision making process plagued with uncertainties, vagueness and complication. Interval-parameter Linear Programming (ILP) is widely used to deal with uncertainties existed in the MSW system and to assist optimal decision making. However, the existing ILP solution algorithms, i.e., best-worst case algorithm and 2-step algorithm, are found to be ineffective through a validity checking process. Moreover, the results from ILP can not reflect the linkage between decision risks and the system return. In this study, a fuzzy risk explicit interval-parameter linear programming (FREILP) model is developed and applied to the long-term planning of the MSW management system in Halifax Regional Municipality (HRM). This method is specifically designed to deal with extensive uncertainties existed in the MSW management system and to provide decision supports to HRM planners. In the model, ILP is used to reflect uncertainties existed in both objective function and constraints. Based on the basic ILP, a risk function is defined to assist in finding solutions with minimum system cost while minimizing the system risk, under certain aspiration levels. The aspiration level could be conservative, medium or aggressive, and can thus be presented as a fuzzy set to reflect the preference of decision makers. Three sets of solutions are obtained accordingly. Besides, the model was also solved under the aspiration level from 0 to 1, with a step of 0.1, for providing a comprehensive decision support. This approach can effectively reflect dynamic, interactive, uncertain characteristics, as well as the interactions between overall cost and risk level of the MSW management system, thus provide valuable information to support the decision-making process, such as waste allocation pattern, timing and expansion capacities of the municipal solid waste management activities. The result can directly reflect the tradeoff between decision risks and the system return.
533

Regional agreements on the transboundary movement of hazardous waste : efforts toward sustainable development

Warrick, Cynthia Ann 08 1900 (has links)
No description available.
534

Quantification of complex phosphorus removal reactions occurring within wetland filtration treatment systems

Sikdar, Anamika 20 December 2007 (has links)
In a constructed treatment wetland applied to domestic wastewaters, long term studies and increased operational experience indicate that phosphorus removal is variable or inconsistent, especially in cold-climate applications. These inconsistencies can be attributed to the complexity of phosphorus removal mechanisms, and the lack of consideration of these complexities in the design, installation and operation of these treatment systems. Sorption of phosphorus to the wetland media is generally considered to be the major removal mechanism. The research described in this thesis was conducted to determine the most suitable material for application in a constructed wetland and a post wetland-filter to treat phosphorus in wastewater effluents, taking advantage of sorption processes. The present work was conducted at lab (bench) scale. Three potential sorptive media were studied in the research program, namely gravel, slag and clinker. Several methods for media analysis were investigated as potential screening tools for media selection. To determine the various forms of phosphorus in the media, sequential extraction tests were considered to be most relevant and useful for this research. Batch testing and flow cell testing along with sequential extraction tests were conducted to predict the sorption capacity and performance of the media for the long term (10+ years) removal of phosphorus. The protocols developed in this thesis permitted a rigorous assessment of the media and should be applied in any assessment of sorptive media to select the best medium. Gravel showed some sorption of phosphorus although it was not sufficient to meet the regulatory limits for the effluent concentration. Clinker and slag showed high sorption capacity as compared to gravel and the observed effluent concentration was below the regulatory limits. All three media showed the presence of background phosphorus, with clinker having the highest amount of background phosphorus. However, except gravel, clinker and slag did not show any significant amount of phosphorus being leached out during low phosphorus loading conditions. Taking all factors under consideration, slag and clinker were identified as good media for phosphorus removal. Media that have proven to have high sorption capacities and also retention capabilities should be considered for applications where phosphorus removal is the prime objective. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2007-12-10 11:40:49.657 / NSERC
535

Waste pulps as biosorbents for metal recovery

Al-Haj Ali, Ahmad January 1984 (has links)
No description available.
536

Waste minimisation clubs in South Africa : towards a sustainable model.

Hurth, Alexander. January 2005 (has links)
Every time a good is produced, waste occurs as an unwanted by-product. Waste has become a real environmental issue across the world, contributing to the degradation of the environment and human health. As part of a local and international effort to lessen industrial pollution, a concept to reduce waste production at source was introduced to companies in the early 1990s. Pioneered in the Netherlands and the United Kingdom (UK), this concept has been termed 'waste minimisation'. Waste minimisation is achieved by implementing changes to business practices and processes, such as improved housekeeping (e.g. prevention of spills), and changes to equipment that is less wasteful. It is often undertaken by a group of organisations, including for example service providers, manufacturing companies and regulators that join a waste minimisation club (WMC). This provides an opportunity in which training can be received by, waste minimisation assessments made on, and information and ideas about waste reduction at source exchanged by member companies. WMCs have been used successfully in Europe to achieve waste minimisation in industry and residential communities. This study aims to contribute to the development of a sustainable WMC model in South Africa. It analyses the WMC support structures in South Africa and compares them to support structures offered in the UK. This offers a point of reference from which the impact of South African support structures on WMCs in general, and the Pietermaritzburg Waste Minimisation Club (PWMC) in particular, can be established. The PWMC consists of small and medium companies across sectors, each with less than 200 employees and with an annual turnover less than 40 million rand. The club was initiated by the Pollution Research Group of the University of KwaZulu-Natal (UKZN). It was the first of its kind in South Africa, having been facilitated on a small budget by staff and students from the UKZN. The study found that the self-help approach adopted by the PWMC was only partially successful. The PWMC was successful in terms of raising awareness of its members to waste minimisation issues. The study also found that member companies, both from the PWMC and WMCs generally, need to be shown in practical terms that 2 waste minimisation can result in financial savings before management buy-in can be attained. If more University manpower had been allocated, in the form of students for instance, to identify and orchestrate implementation of sustainable waste minimisation solutions, the PWMC member adoption rate of waste minimisation may have been raised. The small PWMC budget may have made this impossible, however. Lack of funding may also have prevented facilitators putting together a large support team, as has been done for a similar and more successful project in England. This demonstrates that self-help WMCs need an initial funding boost to be successful. This funding should be invested in gaining buy-in from company personnel rather than to drive the waste minimisation process on behalf of member companies. Driving waste minimisation on behalf of companies or 'hand-holding' leads to a passive acceptance of waste minimisation as is currently the case in South Africa, as well as 'shirking' as has been observed in the UK. Such a facilitated self-help approach can then lay the basis for WMCs, which use the support infrastructure established by their predecessors. Studies of WMCs in England and Wales based on a self-help approach showed that they achieved financial savings that are comparable to those in demonstration clubs. The promotion of such sustainable WMCs in South Africa needs to be performed by a central support agency such as the British Envirowise. Envirowise was seen to successfully promote waste minimisation among those it reached. However, it reached only a small percentage of overall industry. A successful South African agency therefore needs to promote itself effectively and nation-wide. A successful South African Envirowise organisation should also facilitate the creation of WMCs by leading a forum of industry, service providers, higher education and waste minimisation champions of proven worth, to create an action plan for WMC development for each province. Each province would then allocate funds for a waste minimisation champion who, in conjunction with the local development agency, would create a provincial action plan for the development of facilitated self-help WMCs. The local support and expertise recruited to form and manage WMCs would decrease costs and leverage income. This kind of support agency needs to be upheld by waste management legislation based on the concept of sustainable development, recognising the need for environmental protection alongside that of economic growth. To date no such legislation is in place in South Africa. It is hoped that the White Paper on Integrated Pollution and Waste Management, which endorses the principle of sustainable development alongside with the necessity to reduce waste at source, will form the basis for a successful South African WMC culture. / Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
537

The sorption of textile dyes by activated carbon.

Smith, Chadwick Perrin January 1971 (has links)
No description available.
538

Removal of hexavalent chromium compounds from industrial wastes.

Weeks, Robert Franklin 12 1900 (has links)
No description available.
539

Scaling of black liquor in falling film evaporator

Suren, Aydin 08 1900 (has links)
No description available.
540

The transport of radioisotopes by fine particulate matter in aquifers

Champlin, Jerry B. Francis 12 1900 (has links)
No description available.

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