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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.
181

Tertiary biovalorisation of Grape pomace

Angadam, Justine Oma January 2018 (has links)
Thesis (Masters of Environmental Health)--Cape Peninsula University of Technology, 2018. / In the Western Cape, South Africa and other regions globally, grape pomace (GP) is one of the abundant agro-waste from the winery industry. This study reports on the hyper-extraction of fermentable sugars from GP treated with white rot fungi (WRF) Phanerochaete chrysosporium BKMF 1767 to facilitate improved biovalorisation for total reducing sugars (TRS) extraction in conjunction with Nepenthes mirabilis digestive fluids. TRS were quantified using the 3,5-dinitrosalicylic acid (DNS) reagent method. The free readily dissolvable sugars from the GP recorded for the bio-treated (BT) samples was 206.39 ± 0.06 mg/L and for the untreated (UT) samples was 271.05 ± 0.02 mg/L. Overall, the TRS yield for the Bio-treated (BT) and untreated (UT) samples was recorded as 205.68 ± 0.09 and 380.93 ± 0.14 mg/L, respectively, using hot water pretreatment (HWP) with 2266.00 ± 0.73 (BT) and 2850.68 ± 0.31 mg/L (UT), respectively, for dilute acid pretreatment (DAP); with 2068.49 ± 6.02 (BT) and 2969.61 ± 8.054 mg/L (UT) respectively, using the cellulase pretreatment (CP) method. Using the HWP as a reference, the relative increases imparted by the biotreatment was higher (51%) for DAP and low (33%) for CP. The combination of conventional used pre-treatment methods (hot water pretreatment, dilute acid pre-treatment, and cellulase pre-treatment) in a single pot system was also done while monitoring the total residual phenolics (TRPCs) in the samples. Furthermore, powder X-ray diffraction (pXRD) were used to measure the crystallinity index (CrI) and functional groups of pre- and post-pretreated GP to ascertain the efficiency of the pre-treatment methods, with quantification of lignin, holocellulose, and ash. Overall, the TRS yield for N. mirabilis pre-treated agro-waste was 951 mg/L ± 4.666 mg/L, with biomass having a lower CrI of 33%, and 62% residual lignin content. Furthermore, reduced TRPCs were observed in hydrolysate, suggesting limited inhibitory by-product formation during N. mirabilis pre-treatment
182

Economic and environmental input-output modeling: building material recycling

Choi, Taelim 14 November 2012 (has links)
A key dimension to improving urban economic and environmental sustainability is the efficient use of resources through recycling. A thriving recycling system requires not only effective institutional policies and community-wide diversion efforts, but also a competent local and regional recycling industry. Although the recycling industry has traditionally been recognized as a local service and fringe industry, it has noticeably transformed into an integral segment of industrial production systems as manufacturers have increasingly begun to adopt the principle of extended producer responsibility. Despite such changes, urban and regional theory and planning research has largely disregarded the industrial aspect of recycling, contributing to the dearth of information about the organizational and spatial patterns of the recycling industry and the impact of the establishment of recycling systems on local and regional scales. Given the knowledge gap, this dissertation addresses two questions: 1) What is the logic of the industry organization and spatial pattern of recycling industry in different institutional contexts? and 2) How is the economic and environmental impact of recycling systems determined in cases of construction and demolition waste recycling and waste carpet recycling? To answer the first question, this research develops a theoretical model that explains how recycling industrial activities are spatially distributed in light of institutional and organizational theories. The theoretical model characterizes organizational decisions pertaining to recycling functions and suggests spatial patterns of recycling systems. With respect to the second question, this research constructs a regional environmental input-output model on the metropolitan scale. It estimates regionalized energy use coefficients and greenhouse gas emission coefficients using various sources of data mainly compiled from the Manufacturing Energy Consumption Survey 2006, the State Energy Consumption Estimates, and the Commodity Flow Survey 2007. Based on regional input-output tables coupled with the regionalized environmental coefficients, this research quantifies, through simulations, the net economic and environmental impact of a localized construction and demolition waste recycling system in the San Francisco metropolitan area and regional carpet recycling systems in the Atlanta and Seattle metropolitan areas. Results of the simulations reveal that 1) the localized construction and demolition waste recycling system provides moderate economic benefits because of the limited job creation potential of mechanized recycling processes and yields relatively small environmental benefits with respect to the total weight processed; 2) wider adoption of the deconstruction technique expands job opportunities, increases energy savings, and reduces greenhouse gas emissions during the course of construction and demolition waste recycling; 3) regional-scale waste carpet recycling systems, in particular recycled nylon 6 production, create sizable new job opportunities and provides environmental benefits of energy savings and greenhouse gas emission reduction despite the long-distance transportation of waste carpet. These results suggest that policies that promote recycling industrial activities can significantly contribute to the economic and environmental sustainability of metropolitan areas.
183

Life cycle assessment of solid waste collected from household in Macau

Niu, Ru Xuan January 2011 (has links)
University of Macau / Faculty of Science and Technology / Department of Civil and Environmental Engineering
184

Local Economic Development Agencies' Support for Construction and Demolition Recycling

Patterson, Lynn M. 06 April 2007 (has links)
The construction and demolition (C and D) recycling industry creates economic opportunity through business activity; promotes equity through workforce training and partnerships; and helps to conserve natural resources through the reuse, remanufacturing, and recycling of C and D debris. While C and D recycling satisfies traditional local economic development goals, it also addresses broader goals of progressive, and sustainable local economic development. The general planning literature shows an increasing interest in sustainability; however, there have been fewer studies on sustainable local economic development initiatives. This research examines the current state of local economic development agency support for the C and D recycling industry as an economic development strategy. In doing so, the dissertation assembles the array of activities local economic development agencies used to support the industry; identifies distinguishing policy or contextual characteristics of agencies that actively supported the industry from those that did not; and assesses whether the agencies support for C and D recycling fit within the rational planning model. Using data from a national survey of local economic development agencies, the study categorizes the local economic development tools used to support the industry. Results show that a combination of traditional, progressive, and sustainable local economic development tools are adapted and newly created to satisfy the specific needs of this specialized industry. Multiple discriminant analyses identify key characteristics of the agencies that support C and D recycling. These characteristics include previous support for the general recycling industry, the presence and support of environmental enterprise zones and eco-industrial parks, and knowledge of local landfill capacity issues. Overall, the agencies that actively supported C and D recycling engage in activities associated with sustainable local economic development. The descriptive and statistical analyses are combined with the surveys qualitative responses to determine that local economic development agencies do not operate under a strict interpretation of the comprehensive rational planning model in their support of C and D recycling. Instead, local economic development agencies use modified rational and reactive planning strategies in their support of the industry. The study concludes with policy recommendations to increase local economic development agency support for C and D recycling.
185

Partnership for sustainable waste management: a case study of the food waste recycling partnership scheme in HongKong

Lam, Yik-man., 林奕雯. January 2012 (has links)
Waste management is one of the key issues of sustainable development. In Hong Kong, there is food waste management measures but it seems that they have a fair share of limitations. The amount of food waste disposed rose from 3,154 tons in 2005 to 3,237 tons in 2010, which has not shown a significant reduction in volume in recent years. Businesses are becoming more aware of their corporate social responsibility and they definitely have a role to play in sustainable food waste management. Food waste management requires a large amount of resource input and infrastructural support, therefore a collaborative network between the government, businesses and social organizations will surely allows for better performance. The Food Waste Recycling Partnership Scheme (FWRPS) is chosen to be the subject of this case study. It is a partnership program aiming to tackle the food waste problem in Hong Kong’s private sector. A total of 18 companies are chosen as case subjects for the study and are divided into three groups: 1) the participants of the FWRPS; 2) the non-participants of the FWRPS but with self-initiatives for food waste management and 3) the companies without much food waste management initiatives. The three groups are then compared and contrasted upon the drivers, barriers to food waste management and the role of the FWRPS towards effective food waste management. Major factors are drawn from the study such as corporate leadership and resource availability. It is found that those driving and hindering factors varies as companies adopt different food waste management options. In creating these differences, the FWRPS also plays an important role. The scheme succeeded in facilitating food waste management in the private sector as it allows resource pooling and knowledge input. It also has limitations such as the small scale and the lack of promotion. Such partnership would be effective only if each partner is committed to work towards the same objectives. Also, the partners should have their own roles and shoulder their responsibilities. For example, the government should provide the required infrastructure while non-governmental organizations focus on environmental education. In the long run however, the private sector should tailor its own system of food waste management along with legislative support from the government. / published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
186

Food waste management in a Hong Kong secondary school campus

Ngai, Ho-yee., 危可兒. January 2012 (has links)
Food wastage is becoming a serious problem in Hong Kong. At present, Hong Kong relies simply on landfills to dispose of its waste. Nevertheless, such reliance is not sustainable. It may also lead to different social and environmental problems. With the primary aim to lessen environmental damage and achieve environmental sustainability, food waste recycling can save energy, conserve resources and prolong lifespan of landfills. Therefore, it is important to educate youngsters in order to develop their responsibility and habits in protecting the environment. It has been reported that recycling awareness should be instilled into people’s mind from their childhood. Through food waste recycling programmes held in schools, students can increase their awareness and knowledge in that aspect and develop skills for the solutions of environmental problems. On the other hand, such programmes would help reduce food waste at source and draw public attention to the food waste problem. The aims of this study focus on the introduction of a food waste management programme in a Hong Kong secondary school campus and exploring the feasibility and viability of extending it to other secondary schools in Hong Kong in order to minimize waste disposed to landfills. The study shows that the students may gain knowledge about food waste recycling through practical field experience by joining both of the Food Waste Recycling Programme and the Organic Farming Programme under the food waste management policies developed in the school. They allow students to engage more in recycling behavior and increase their awareness of food waste avoidance, reduction and recycling in their daily life. With the tripartite cooperation the Government, the participating schools and the secondary school students, the food waste management held in the school campus is feasible and viable to extend to other secondary schools in Hong Kong in order to lessen the pressure of local landfills. / published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
187

Essays on production and pricing decisions

Mok, Yat-Koon 05 1900 (has links)
There has been considerable interest in finding and explaining the basic elements that can drive product quality up. In the literature this is largely done by modelling the effects of investing in learning and process improvement, and of cost reduction. In the first essay, demand is modelled as a function of price and quality. With this demand function, the firm should produce output of higher quality, the increase in quality being dependent on consumers’ sensitivity to quality and to price, and the effect of technological improvement on product price and quality are very different from those when the demand is a function of price alone. Some twenty states in the U.S. have passed recycling laws which mandate consumption of old newspaper by the newsprint industry. To study the effect of regulation, a model is used in which two firms compete under the regulatory constraint—one firm producing the recycled product, the other the virgin product. Assuming the regulatory constraint is binding, and the demand for the recycled product is derived solely from the legislation, interesting results such as the two firms share equal profits, and consumers pay higher average price in competitive equilibrium than the cartel price, are obtained in the second essay. The two firm model is generalized to include n firms which compete under the same kind of regulatory constraint in the third essay. Results similar to the two firm case are obtained. When the recycled product and the virgin product are partially substitutable, regulation that mandates consumption of the recycled product results in infinitely many equilibria. A dominating equilibrium exists if the demand parameters satisfy a certain condition, otherwise it is not clear how to select an equilibrium. On the other hand, a suitable tax on the virgin product, or its producer, serves to induce compliance with the recycling policy and equilibrium selection. The equilibrium prices and profits of the two firms under the schemes of production tax, excessive consumption tax and progressive profit tax are examined and compared in the fourth essay. It is interesting to find that the tax rate for excessive consumption is comparatively low and, in equilibrium, this tax scheme collects no tax payment.
188

Waste management through recycling and composting : a case study of some schools in greater Edendale, Pietermaritzburg, KwaZulu-Natal.

Nxumalo, Felix Thembinkosi. January 1999 (has links)
The study investigated the involvement of primary and secondary schools in waste management through recycling and composting, and the perceptions of teachers and pupils with regard to waste management. It also investigated the local municipality's attitude towards using schools to inculcate the culture of own waste management. It further investigated some of KwaZulu Natal's recycling industries/agents' attitudes toward using schools as "mini" depots for collection of recyclable materials. It was found that according to teachers perceptions most of the primary schools are engaged in waste management practices through recycling and composting, while secondary schools are less involved in waste management practices through recycling and composting. The results revealed that 53% of primary schools are involved in recycling projects, while only 10% of secondary schools are involved. It was also found that both primary and secondary school teachers are willing for their schools to be involved in waste management practices. Primary school pupils are more enthusiastic in collection of recyclable materials and composting projects as means of waste management as compared to secondary school pupils who are less interested. The results further revealed that there are no educational programmes that are initiated by the Pietermaritzburg-Msunduzi Municipality to inculcate the culture of waste management among the school pupils. There are a few industries that collect recyclable materials from schools in Greater Edendale by putting paper banks in some of the schools. It was also found that the Keep Pietermaritzburg Clean Association has an educational programme for waste management with some of the schools in Greater Edendale. This programme is called Environmental Award System for Youth (EASY), whereby schools receive awards for activities that they are involved in to manage waste. It is recommended that organisations such as the Greater Edendale Environmental Network be encouraged to establish educational programmes to help motivate and make pupils aware of the value of waste management. Recycling industries should also target primary and secondary schools for collection of recyclable materials, rather than only focusing on tertiary institutions. If this is done children will gradually become aware of the concept and value of recycling. Through the involvement of schools in waste management the public can be educated more to the role of responsible waste disposal and management. / Thesis (M.Env.Dev.)-University of Natal, Pietermaritzburg, 1999.
189

An analysis of municipal solid waste management in South Africa using the Msunduzi Municipality as a case study.

January 2009 (has links)
Municipal Solid Waste generation has become an inevitable consequence of lifestyles and daily living. However, the nature (quantity and quality) of this waste stream can vary and is largely dependent upon the manner in which waste production is managed, by both government and the public. The increasing practices of littering, dumping and burning of solid waste by households (and industries though not extensively dealt with in this study) in South Africa has led to the finding that municipal solid waste is being irresponsibly managed. In this regard, it becomes necessary to investigate the attitudes and behaviour of individuals and households toward solid waste practices, which further include mitigating measures such as reduction, reuse and recycling for the generation of solid waste. The role of the South African government in providing a refuse removal and safe disposal service to all citizens is suggestive of the responsible role of government to ensure that solid waste is being effectively managed by all sectors of society. The aims of this study in light of the above were to review the municipal solid waste policies and strategies of local government authorities in South Africa, highlighting the shortcomings and discrepancies that exist between legislative policies and actual management practices; which is also reflective of the attitudes and approaches to solid waste management by households. This was achieved by focusing on the case study of the Msunduzi Municipality and included investigations into socio-economic and cultural influences on solid waste disposal practices. The objectives of the study were achieved by means of a questionnaire survey that elicited specific responses from 650 sampled households in five suburbs of differing socio-economic status. A further analysis to identify the nature of household municipal solid waste for landfilling from three suburbs of differing socio-economic status was conducted by categorizing 25 tons of garbage at the New England Road Landfill Site, leading to inferences about consumer purchasing power and disposal practices. Further, key personnel in the Msunduzi Municipality’s waste management division were interviewed to ascertain the solid waste challenges faced at local municipal and national levels of government. The study revealed several significant findings of which the most important is that the implementation of South Africa’s national municipal solid waste legislation policies and strategies are inconsistent with local government practices and procedures; thus compromising equity, efficiency, effectiveness and the sustainability of municipal solid waste disposal. Factors contributing to this are shown to be inadequate management and service delivery. The research has shown that monitoring and control systems which purported to ensure environmental sustainability are lacking and inadequately address issues where the implementation of municipal solid waste regulations are in contravention with national solid waste policies. The outcomes of the questionnaire survey and the assessment of household municipal solid waste for landfilling reveal that socio-economic status and culture do in fact influence the nature of solid waste and the disposal methods used by residents. The receptiveness of households towards adopting suggested municipal solid waste disposal practices was also investigated. The non-compliance of residents with municipal solid waste legislation and policies points towards a lack of monitoring and control measures, thereby not providing for a sustained and adequate service delivery which is environmentally sound. The research further suggests that all sectors of the South African public and the government are inadequately informed in terms of aspects of municipal solid waste. This has led the researcher to recommend that further education and awareness campaigns and its role in environmental sustainability are needed so that a sharing of responsibility between government and the public can be effected to aid municipal solid waste management in the country. It is argued that the insight into the roles of socio-economic status and cultural influences over solid waste practices provide a platform from which municipal authorities can work to specifically address the problems associated with municipal solid waste at a community level. It is the task of the national government to ensure that South Africa’s municipal solid waste is being responsibly managed at the local municipal levels so that the health and safety of the environment and its citizens are suitably addressed, hence the focusing on solid waste legislation and national policies (which have been recognized internationally as being environmentally sound and sustainable) must be translated in terms that local municipalities can adopt, assuming that they have been sufficiently empowered in terms of both knowledge and adequate budgeting. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
190

A policy analysis of cleaner technology : a case study of Mondi Limited.

Mokoena, Kgauta Sylvester. January 2003 (has links)
The pollution problems resulting from industrial production activities result in the deterioration of our natural environment. That is why something needs to be done in order to preserve our environment. Conservation alone is not enough. Development is needed. Waste minimisation through applying Cleaner Technologies can help the country in the reduction of waste production and improve industry's environmental management processes. This study was based on an investigation into the adoption of Cleaner Technology. The study argues that elements of Cleaner Technology and the application of tools and strategies to practice Cleaner Technology are very useful for any industry. The costs of Cleaner Technology to companies cannot be compared with the benefits they can get from adopting Cleaner Technology. Mondi Limited concentrates on the product element of Cleaner Technology. It applies the recycling and re-use strategies in or~er to achieve product modification and input substitution. The organisation and knowledge elements are very strong and supportive to the technique element that is used at the Mondi Paper Mill. These three elements contribute to the increased efficiency, improved quality of intended products and waste minimisation through re-use and recycling. The question emerges about what government can or should do in return to companies like Mondi since they contribute towards the sustainability of our natural resources. / Thesis (M.Soc.Sc.)-University of Natal, Pietermaritzburg, 2003.

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