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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

A process systems methodology for environmental impact minimization

Stefanis, Stavros Konstantinou January 1997 (has links)
No description available.
22

Legislative support for waste reduction initiatives

Liu, Wai-leung., 廖為良. January 1997 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
23

Application of analytical chemistry to waste minimisation in the powder coating industry.

January 2005 (has links)
A local company instituted a new chemical procedure in their spray phosphating system used in the pretreatment of large components for industrial racking systems. An inorganic conversion coating is deposited on the workpiece surface during phosphating and this prepares the surface to receive an organic top-coat. The organic coating is applied to the workpiece surface in the form of a powder and cured to form a continuous film about 80 u.m thick. The solution chemistry of the phosphating system was monitored by sampling and chemical analysis and taking direct reading instrumental measurements on the process and rinse solutions. The process was also evaluated using the results of a waste minimisation audit. This involved gathering data on composition, flow rates and costs of inputs and outputs of the process. Two types of information were collected and used during the audit, namely chemical monitoring (concentration levels of Na, Fe, Zn, Mo, Mn and Cr and measurements of conductivity, TDS, SS and pH) and water usage data on the Phosphating Line and existing data (raw materials, workpieces and utility inputs as well as domestic waste, factory waste and scrap metal outputs). The data were analysed using four established waste minimisation techniques. The Scoping Audit and the Water Economy Assessment results were determined using empirically derived models. The Mass Balance and the True Cost of Waste findings were obtained through more detailed calculations using the results of the chemical analysis. The results of the audit showed that the most important area for waste minimsation in the Phosphating Line was the (dragged-out phosphating chemicals present in) wastewater stream. According to the scoping audit, water usage had the third highest waste minimisation potential behind powder and steel consumption for the entire powder coating process. While the scoping audit and the specific water intake value showed that water consumption for the process was not excessive, it did not indicate that the pollution level in the rinse waters was high. Further, drag-out calculations showed that drag-out volumes were typical of those found in the metal finishing industry. However the presence of high levels of metal species in the rinse waters was highlighted through the chemical monitoring of the Phosphating Line. The True Cost of Waste Analysis estimated potential financial savings for the effluent stream at about R8000 for a period of 105 days. However this does not take into consideration the cost of the liability associated with this stream when exceeding effluent discharge limits (given in the Trade Effluent Bylaws) or of the chemical treatment necessary to render this stream suitable for discharge to sewer. Intervention using only "low-cost-no-cost" waste minimisation measures was recommended as a first step before contemplating further areas for technical or economic feasibility studies. However, a further study involving monitoring the sludge was recommended in order to establish the potential financial savings offered by this waste stream. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
24

Critical factors in effective construction waste minimisation at the design stage: a Gauteng region case study

Wortmann, Anine Eschberger 28 April 2015 (has links)
A research report submited to the Faculty of Engineering and the Built Environment, of the University of the Witwatersrand, Johannesburg, in part all fulfillment of the requirements for the MSc. (Building) in Construction Project Management. / Construction waste minimisation and avoidance at the design stage of a construction project is the most favourable solution in the existing waste management hierarchy triangle. However, there are currently only a limited number of exploratory and context-specific studies that state effective construction waste minimisation factors which can be implemented during the design stage. This can be regarded as a relatively new concept and new research topic, especially as no studies have been done in a South African or a Gauteng region context. This research report aims to address this local knowledge gap. The research method included an initial conceptual framework of factors (identified from surveying both global and local literature) as a launch pad in order to quantitatively survey design consultants in Gauteng with regards to both the significance and ease of implementation of the identified factors. The research target population consisted of; architects, architectural technologists, architectural draughtsman, structural engineers, structural technologists, structural draughtsman and finally sustainability consultants. The target population was further narrowed by only including designers who have both attempted to minimise construction on greenfield projects in Gauteng and who have received Green Building Council of South Africa (GBCSA) accreditation on the same project. This report presents a hierarchical list of twenty-six critical factors that can be implemented during the design stage in order to minimise or avoid construction waste in the context of Gauteng, South Africa. The report further indicates which of these factors will be easier to implement than others. These factors are aimed mainly at clients of construction projects, as they are in essence the stakeholders who will contractually enforce designers to implement these construction waste minimisation factors in order to lower project costs. Furthermore; these factors will also serve as valuable references for the Gauteng Provincial Government as the factors can be utilized in order to drive provincial construction waste regulations and eventually national reform.
25

A review of the use less plastic bags campaign /

Dai, Lai-man, Raymond. January 1998 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1998. / Includes bibliographical references (leaf 107-110).
26

Planning on treatments of solid domestic waste in Hong Kong /

Cheng, Hoi-cheung. January 1997 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1997. / Includes bibliographical references.
27

Community participation in waste minimization : the case of Emfuleni Local Municipality / Nompazamo Alma Ludidi

Ludidi, Nompazamo Alma January 2009 (has links)
The purpose of this research is to understand factors contributing to successes and challenges in community participation especially in waste minimization initiatives; in order to inform policies and contribute to improve the design of the initiative. The objectives of the research are: firstly, to understand the current state of public participation in waste minimization at Emfuleni Local Municipality. Secondly, it is to determine the extent of willingness of the community to participate in waste minimization initiatives. Thirdly, to determine strategies on how to promote public participation in waste minimization. Fourthly, to identify constraints and challenges of public participation in waste minimization and what kind of support is required for the community to participate in waste minimization initiatives at Emfuleni Local Municipality. Respondents were drawn from fifty households within the community of Bophelong Extension 13, Emfuleni Recycling groups, Waste Management officials, Gauteng Department of Agriculture, Conservation and Environment stake holder participation unit and Waste Buyers in Vanderbijlpark. The researcher employed mainly a qualitative research design and data was collected through questionnaires and interviews. Quantitative study was done on officials and responses were ranked according to the importance of the factors influencing community participation. The findings of this research indicate that the community is willing to participate in waste minimization initiatives. 42% of respondents are currently NOT participating in waste minimization initiatives. It was noted that all community respondents promised and are willing to participate in waste minimization strategies. The research further indicates that there is a considerable number of constraints and challenges prohibiting successful community participation in waste minimization. The constraints include lack of knowledge especially regarding composting initiatives to minimize organic waste and the separation of waste, lack of infrastructure to exchange waste for cash, lack of time, lack of transport, lack of political support, lack of starter packs to initiate own waste minimization plant and lack of financial support to ensure that waste minimization initiatives create opportunities for job creation. This study recommends, amongst others, that the community requires support to participate meaningfully in waste minimization initiatives in the form of: awareness and education, infrastructure for reclaimed waste, waste recycling bins, project funding, community involvement and support from the Emfuleni Local Municipality and the private sector. / Thesis (M. Development and Management)--North-West University, Vaal Triangle Campus, 2009.
28

Resource conservation and optimization via process integration

Gabriel, Frederico Burjack 12 April 2006 (has links)
The process industries are characterized by the enormous use of natural resources such as raw materials, solvents, water, and utilities. Additionally, significant amounts of wastes are discharged from industrial facilities. As the world moves toward sustainable progress, that is, meeting the demand of the current generation without affecting or compromising the new generation, future process facilities must focus on resource conservation and pollution prevention. The purpose of this work is to introduce a new process integration methodology for the conservation and optimization of resources in the process industries. The work is also geared towards reducing waste discharge from the processing facilities. The optimal management of fresh resources and waste disposal requires the appropriate allocation, generation, and separation of streams and species. Material recycle/reuse/substitution, reaction alteration, and process modification are some of the main strategies employed to conserve resources in the process industries. The overall problem addressed in this dissertation can be stated as follows: Given is a process with a number of streams (sources) that are characterized by certain criteria (e.g., compositions of certain compounds, targeted properties) where these streams can be utilized in a number of process units (sinks) if they satisfy given constraints on flow rate, compositions, and/or properties. Additionally, interception devices may be used to adjust stream criteria. The objective is to develop targeting procedures and synthesis tools for the identification of minimum usage of fresh resources, minimum discharge of waste, and maximum integration of process resources. The devised methodology addresses four classes of problems: • Targeting techniques using direct recycle strategies • Recycle and interception procedures for single-component systems • Recycle and interception procedures for multi-component systems • Property integration for direct recycle strategies The framework provided by this dissertation couples traditional mass integration with groundbreaking property integration techniques to target, synthesize and optimize a plant for maximal conservation of resources. In particular, this work introduces new techniques such as material recycle pinch analysis, simultaneous recycle and interception networks, and property-based allocation. Additionally, graphical, algebraic, and optimization approaches are developed and validated with case studies in order to illustrate the applicability of the devised procedures.
29

Transforming rubbish into nourishment in a no man's land: food wastage and recycling in Hong Kong

Wong, Man-yee, 黃敏儀 January 2001 (has links)
published_or_final_version / Journalism and Media Studies Centre / Master / Master of Journalism
30

Community participation in waste minimization : the case of Emfuleni Local Municipality / Nompazamo Alma Ludidi

Ludidi, Nompazamo Alma January 2009 (has links)
The purpose of this research is to understand factors contributing to successes and challenges in community participation especially in waste minimization initiatives; in order to inform policies and contribute to improve the design of the initiative. The objectives of the research are: firstly, to understand the current state of public participation in waste minimization at Emfuleni Local Municipality. Secondly, it is to determine the extent of willingness of the community to participate in waste minimization initiatives. Thirdly, to determine strategies on how to promote public participation in waste minimization. Fourthly, to identify constraints and challenges of public participation in waste minimization and what kind of support is required for the community to participate in waste minimization initiatives at Emfuleni Local Municipality. Respondents were drawn from fifty households within the community of Bophelong Extension 13, Emfuleni Recycling groups, Waste Management officials, Gauteng Department of Agriculture, Conservation and Environment stake holder participation unit and Waste Buyers in Vanderbijlpark. The researcher employed mainly a qualitative research design and data was collected through questionnaires and interviews. Quantitative study was done on officials and responses were ranked according to the importance of the factors influencing community participation. The findings of this research indicate that the community is willing to participate in waste minimization initiatives. 42% of respondents are currently NOT participating in waste minimization initiatives. It was noted that all community respondents promised and are willing to participate in waste minimization strategies. The research further indicates that there is a considerable number of constraints and challenges prohibiting successful community participation in waste minimization. The constraints include lack of knowledge especially regarding composting initiatives to minimize organic waste and the separation of waste, lack of infrastructure to exchange waste for cash, lack of time, lack of transport, lack of political support, lack of starter packs to initiate own waste minimization plant and lack of financial support to ensure that waste minimization initiatives create opportunities for job creation. This study recommends, amongst others, that the community requires support to participate meaningfully in waste minimization initiatives in the form of: awareness and education, infrastructure for reclaimed waste, waste recycling bins, project funding, community involvement and support from the Emfuleni Local Municipality and the private sector. / Thesis (M. Development and Management)--North-West University, Vaal Triangle Campus, 2009.

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