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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.
171

Product stewardship initiatives : the case of post consumer paint in BC

Mugabe, Barbara Caroline 11 1900 (has links)
The outcomes of the paint stewardship program in British Columbia are examined to assess whether the objectives of the program and the principles of product stewardship are being achieved. The objectives are to: 1) compel the paint industry and consumers to take responsibility for waste paint; 2) minimize the volume of paint landfilled; 3) raise consumer awareness about the impacts on the environment of excessive waste generation, and the need to opt for environmentally friendly practices.' The methods of research used include secondary literature, a survey and interviews. Due to the unavailability of some crucial data, I could not carry out a proper program assessment. The following are some insights into the program: 1) waste paint collected increased from 1,300,000 equivalent litre containers in 1995 to nearly 3,000,000 in 1997. However, without knowing the volume of paint sold annually, these figures reveal little about the effectiveness of the program; 2) Of the residual paint collected in 1997, 51% was recycled into products other than paint, 30 % involved energy recovery, 11% was landfilled, while 8% was reused. I discussed the need to increase the volume of paint reused as doing so prevents the problem of waste paint from arising in the first instance. There are both benefits and flaws associated with the process of recycling. Compared to reuse, recycling does relatively little to solve the problem of waste reduction; 3) In the absence of crucial data, the objective of compelling the paint industry and consumers to take responsibility for waste paint is so far merely theoratical. The paint program is consumer funded and industry operated. In practice, a 50c ecofee/litre paint has not served as an incentive to encourage consumers to bring residuals to a depot. Nor has it resulted in meaningful changes in consumption habits. A 50c ecofee also means that paint sales will not likely be affected. It appears the industry is charging this low fee despite the fact that it does not lead to the achievements of the objectives outlined for the program. While a paint program is now in place for the processing of residual paint, the program cannot be assessed based on its objectives. To enable meaningful program evaluation, the primary recommendation is for the authorities monitoring the program to collect the relevant data over time in order improve program effectiveness.
172

Making Waste Public

Gambetta, Curt January 2009 (has links)
This thesis questions the boundaries that define waste as a public or private dilemma, investigating these boundaries as productive sites for the imagination of social life. Learning from methods of processing, conveyance and disposal, I investigate a number of possible sites where the architectural mediates the life of a wasted object and the social life that is produced around an engagement with that object. Waste has largely been disappeared from the city and the senses by mechanisms of modern sanitation and architecture, moved to the urban periphery and concealed inside increasingly refined membranes of storage and movement. Though ruptures or discrepancies in the waste stream are often read as signposts of failure of a certain project of the modern city, I read these ruptures or excesses as productive irritants for working and reworking how we conceptualize public space. It is within the friction of overlapping claims made to an issue such as waste that public life emerges.
173

The design of strategic collection systems for recyclable materials

Villanueva, Luis 05 1900 (has links)
No description available.
174

The effect of turbulence on bacterial substrate utilization

Marlar, John Thomas 12 1900 (has links)
No description available.
175

Land disposal of newsprint mill effluents.

Salloum, John Duane. January 1973 (has links)
No description available.
176

The use of complex toxic industrial waste as a fermentation substrate /

Ramsay, Bruce A. January 1987 (has links)
Two complex wastes were considered for biological conversion into a marketable product. One waste, peat runoff water (the waste-water that remains after the mining of peat), was found to be unsuitable for biological conversion to any product since it contained an insufficient quantity of carbon. The other waste, NVR (non-volatile residue, the major waste from the manufacture of nylon 6$ sp prime 6 sp prime$), was found to be a suitable carbon and energy source for the production of PHB (poly-$ beta$-hydroxybutyric acid) by Pseudomonas cepacia ATCC 17697. A general approach to the development of complex toxic wastes as fermentation substrates was formulated. / NVR was found to be toxic to microorganisms. None grew in enrichment culture containing 2.0% NVR. P. cepacia was the most resistant microorganism found. It could grow well in up to 1.3% NVR. It also grew on butanoic, pentanoic, and hexanoic acid as well as 6-hexanolactone. These were found to be the major toxic components of NVR. P. cepacia was grown in a NVR-limited chemostat with a NVR feed concentration well in excess of the toxic NVR concentration. In nitrogen-limited, batch fermentation on fructose, P. cepacia accumulated PHB in excess of 50% of its dry weight. A 2-stage chemostat process for the production of PHB from NVR by P. cepacia was investigated with encouraging results.
177

Utilization of Pulp and Paper Mill Sludge as Filler in Nylon Biocomposite Production

Edalat Manesh, Maryam 21 August 2012 (has links)
The biological treatment of pulp and paper mills effluents results in the production of waste secondary sludge which is hard and costly to dewater and dispose. Secondary sludge, which is structurally comparable to the municipal sewage sludge, is composed of microbial cells, organic woody materials, and ash. In this work, the use of this waste biosolid as renewable and cost-cutting filler in the composite industry is proposed. Moreover, the effect of enzymatic treatment of the waste biosolid on the final properties of the manufactured biocomposite is studied. The high protein content of the secondary sludge (35 ± 5%) and the surface thermodynamics measured by Inverse Gas chromatography (IGC) led us to choose Nylon 11 as the main polymeric matrix. The biocomposites samples produced by compounding and injection molding of different mixtures of dried secondary sludge and Nylon were tested. The results of mechanical strength tests showed that a 10% sludge content does not lead to any significant deterioration of either tensile or flexural strengths. Therefore, it is concluded that the secondary sludge may be used as filler to reduce the cost while maintaining the mechanical properties of Nylon. Enzymatic modification of the waste biosolid to advance its application from cheapening filler to reinforcing filler has also been proposed in this work. Lipase and laccase utilized for the modification of the sludge in order to reduce the hydrophobicity and increase the molecular weight, respectively. Lipase application did not lead to any significant changes in either tensile or flexural strengths. This is attributed to the rather low content of lipids in the sludge. On the other hand, enzymatic modification of the sludge by laccase which increases the molecular weight of the existing lignins, resulted in significant improvement of the flexural strength of the manufactured biocomposite.
178

Utilization of Pulp and Paper Mill Sludge as Filler in Nylon Biocomposite Production

Edalat Manesh, Maryam 21 August 2012 (has links)
The biological treatment of pulp and paper mills effluents results in the production of waste secondary sludge which is hard and costly to dewater and dispose. Secondary sludge, which is structurally comparable to the municipal sewage sludge, is composed of microbial cells, organic woody materials, and ash. In this work, the use of this waste biosolid as renewable and cost-cutting filler in the composite industry is proposed. Moreover, the effect of enzymatic treatment of the waste biosolid on the final properties of the manufactured biocomposite is studied. The high protein content of the secondary sludge (35 ± 5%) and the surface thermodynamics measured by Inverse Gas chromatography (IGC) led us to choose Nylon 11 as the main polymeric matrix. The biocomposites samples produced by compounding and injection molding of different mixtures of dried secondary sludge and Nylon were tested. The results of mechanical strength tests showed that a 10% sludge content does not lead to any significant deterioration of either tensile or flexural strengths. Therefore, it is concluded that the secondary sludge may be used as filler to reduce the cost while maintaining the mechanical properties of Nylon. Enzymatic modification of the waste biosolid to advance its application from cheapening filler to reinforcing filler has also been proposed in this work. Lipase and laccase utilized for the modification of the sludge in order to reduce the hydrophobicity and increase the molecular weight, respectively. Lipase application did not lead to any significant changes in either tensile or flexural strengths. This is attributed to the rather low content of lipids in the sludge. On the other hand, enzymatic modification of the sludge by laccase which increases the molecular weight of the existing lignins, resulted in significant improvement of the flexural strength of the manufactured biocomposite.
179

The degradability of surfactants in textile mill wastes with hydrogen peroxide

Nonaka, Denis Nobuo January 1968 (has links)
No description available.
180

Biodegradability of some dye carriers

Soria, Jose Roberto Rodriguez January 1970 (has links)
No description available.

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