Concern over construction and demolition (C&D) wastes is becoming a prevalent part of any construction project. Historically, landfilling waste materials was the standard solution for most contractors, but as tipping fees have risen dramatically over the past five to seven years, many contractors are looking for alternative methods, such as recycling or waste minimization, to reduce wastes. This thesis investigates C&D wastes and proposes a methodology to address the problem of assessing waste disposal techniques efficiently and economically. A brief history of C&D wastes is provided to understand how and why costs associated with waste materials have risen over the last several years. Current waste management resources are discussed to demonstrate the availability of alternative disposal methods. An overall waste management plan is developed to provide a contractor with a step by step flowchart for analyzing material wastes, quantitatively assessing all costs associated with waste disposal, and implementing and updating the chosen waste management techniques. A case study is provided to illustrate how the waste management plan is used in an actual project. The thesis concludes with a discussion of the potential for further research in the area of C&D waste management. / Master of Science

Many civic groups and local governments are involved in campaigns to safely collect and dispose of "household hazardous waste." Although it is difficult to define, household hazardous waste is generally considered to be any chemical waste generated in a family dwelling which, if disposed of improperly, may be harmful to human health or the environment. Growing concerns are centered around the disposal of these potentially toxic wastes by burying them in landfills or pouring them down drains or storm sewers. The most popular method of addressing the problem of household hazardous waste is that of holding "collection days," at which householders are encouraged to bring their hazardous waste to some central location for proper handling by responsible authorities. Although the availability of information about the total costs of holding these collections days is presently limited, it is apparent that the expense per household served is quite high. Some people have questioned whether the expense is justified, since there has been little documentation of the risks associated with the handling of household hazardous waste in the municipal waste stream. This thesis presents the findings to date of a study examining the quantities of household hazardous waste present in the municipal waste stream (in order to assess the risks associated with their disposal) and the costs associated with collection days. A telephone survey was used to develop a preliminary estimate of the nature and quantity of hazardous waste generated by households in a Virginia city. Cost data from collection days held in Virginia and elsewhere in the United States are documented and discussed. / Master of Science

Disposal of regulated waste has become a major challenge for the generators. Disposal of such waste is regulated by local, state and federal agencies and the problem is intensified because of liability issues, public perception and increasing cost. This document describes the mechanical design, installation and testing of a system that employs bioremediation to disinfect regulated medical waste. Currently marketed treatment systems generally use either heat or extreme pH to disinfect medical waste. The most common and widely accepted of these, incineration, is rapidly losing favor because of undesirable emissions and hazardous by-product. The system described in this document is the first to use a biological process. The advantages of using this system include the absence of harmful effluents or emissions, low cost of operation, reduction of waste volume and disposal directly into landfill and sewers. The evolution of system design from conceptual stage to the design of a system for Lewis-Gale hospital is described. A general overview of the components is presented and the selection and testing criteria are explained. The components used in Lewis-Gale hospital are described with a detailed layout scheme. A detailed failure analysis was done for each component used in Lewis-Gale hospital. This is presented with contingency plans developed for prolonged system failure. Finally, the operators manual developed for the Lewis-Gale hospital is included. / Master of Science

The design and development of a system for disinfecting medical waste at the site of origin is presented. Investigation of the current commercial systems that accomplish this task shows that they all expose the waste to physical conditions that are harmful to all forms of life. Further, most are very expensive to install and to operate. A recently developed biochemical process promises to effectively inactivate harmful pathogenic organisms economically and without the danger of extreme heat or poisonous chemicals. The biochemical process is not yet fully developed. Nonetheless, the development of a marketable system to take advantage of this technology has been initiated. The motivation for developing this technology and the particular system that will employ it is presented. A general overview of the system and components is presented. Previous and suggested future testing strategies are explained. Component interactions and process control are described. / Master of Science

The object of this research was to investigate and evaluate three methods for determination of sulfate and to use the obtained information as a guide in selecting an accurate analytical method with which to conduct a complete analysis of calcium sulfate deposits. The investigation of the analytical methods revealed that the gravimetric method is most accurate for high sulfate concentrations. This method was selected for all analytical work conducted in the study of the deposited material and in the development of a sodium hydroxide-alcohol-water solution for the removal of the calcium sulfate deposits. The initial phases of the development of the sodium hydroxide-alcohol-water solution were discouraging in that the results were inconsistent and could not be reproduced. It was believed that such inconsistencies resulted, primarily, from the method of mixing the solutions, since all mixing was done by weight percentages. The method of mixing was revised, and all subsequent mixing was governed by titration of the solution in order to determine the sodium hydroxide concentration. The alcohol was added after the solution was adjusted to the desired sodium hydroxide concentration. The investigation revealed that, following the immersion period, “air drying" the material had an effect upon the behavior of the sample during the second immersion period. It was seen that the disintegration of more resistant materials could be facilitated by employing such a period for drying the material before a second immersion period. A cost study revealed that application of the proposed method for removal of calcium sulfate deposits from treatment facilities is economically sound and that the cost of application of the method is very small compared to the cost of replacement of facilities. / Master of Science

In this study, solidification and stabilization processes were evaluated for use as a treatment method for electric arc furnace dust. Specific objectives were (1) to develop a solidified material capable of meeting EPA requirements for heavy metal leaching, and (2) to develop a solidified material that could be used for construction. Results from the studies of the untreated electric arc furnace dust showed that the solubility of cadmium is controlled by the hydroxide species. Lead solubility is more complex because its solubility is controlled by a species other than hydroxide and therefore it is more difficult to predict. Studies also indicated that approximately 1.9% of the composition of the electric arc Furnace dust is made up of lead. This study demonstrated that solidification and. stabilization is a viable treatment process for electric arc. furnace dust. Success in treating the electric arc furnace dust by this method, however, depends upon such factors as the compressive strength of the solidified waste, the amount of electric arc furnace dust incorporated in the concrete, and the ability of the solidified waste to remain intact during the Toxicity Characteristic Leaching Procedure (TCLP). Based on these factors, approximately 165 lb dust/cu yd concrete was determined to be the upper limit on the amount of electric arc furnace dust that can be incorporated in such a system. Efforts to improve the quality of the concrete by the addition of a chelating agent was moderately successful; however, the addition of salts to speed the concrete set times was not successful. A model was developed which predicts the required compressive strength of the solidified dust based upon the amount of electric arc furnace dust that is incorporated in the concrete. The model effectively predicts, without performing the TCLP test, whether the solidified material will meet limits for heavy metal required by the EPA. / Master of Science

Submitted in fulfillment of the requirements of the degree of Doctor of Philosophy in Chemistry, Durban University of Technology. Durban, South Africa, 2015. / Over decades synthetic composites have become an indispensable part of our lives with their various applications such as packaging, sporting equipment, agriculture, consumer products, medical applications, building materials, automotive industry, and aerospace materials among others. Although these polymers have the desired properties for the above applications, they are invariably costly. Furthermore, they cannot be easily disposed of at the end of their useful lives and simply pile up and cause significant damage to the environment. However, the dwindling supply of fossil fuel, increased oil prices, together with the growing public concern of greenhouse gas emissions and global warming, has forced scientists to search for new development of sustainable materials from renewable resources. Hence in recent years, there is an increased interest in biocomposite manufacturing with natural resources as environmental issues are addressed. The research work presented in this dissertation is to the best of the author’s knowledge a world-first overall investigation pertaining to the concept of synthesizing a banana sap based bio-resin (BSM) reinforced with banana fibres. In this work the chemical composition of banana sap was determined to investigate the chemical reactions taking place in the resin formulation. BSM was synthesized, characterized and proposed as a potential bio-resin to be used in the biocomposite manufacture for non-functional motor vehicle components. BSM, a hybrid bio-resin was synthesized with equimolar quantities of maleic anhydride and propylene glycol and 50% banana sap. A control resin without the banana sap was also synthesized for comparison purposes. It was proposed that the presence of sugars, esters and pthalates from the sap, determined by HPLC and GC-MS, contributed to the cross-linking of the polymer chain. The acid value and viscosity of BSM were determined and found to be within specification of an industry resin. The molecular weights of the BSM and control resins were 2179 and 2114 units respectively. These were within the required molecular weight of unsaturated polyester resins. The gel and cures times of the BSM were 60% lower than the control resin suggesting that the banana sap behaved as an accelerator for the curing process. The lower cure time meant that using the banana sap in the formulation was cost effective and time saving. The thermal properties of BSM showed improved degradation temperatures and degree of crystallinity compared to the control resin. A parametric study showed that increasing banana sap concentration in the resin formulation led to increased tensile and flexural properties with 50% being the optimum amount of sap to be added to the formulation. The synthesized bio-resin and control resin were applied to biocomposites and characterized in terms of physical, thermal, mechanical, morphological, chemical and biodegradable properties. Mechanical tests indicated a 15 % increase in tensile strength, 12 % improvement in tensile modulus and a 25 % improvement in the flexural modulus, when compared to structures produced without banana sap. Natural fibres present the challenge of poor adhesion to the matrix. Chemical treatment of the banana fibre was done to improve on the compatibility of resin to fibre. Fibre pull-out showed that treated fibres had a better bond than the untreated fibre. Parametric studies were also done to evaluate the effect of fortifying the BSM resin with nanoclay. A 5% clay loading resulted in a 24% increase in tensile strength and 28% increase in flexural properties. Finally biodegradation studies of the BSM bio-resin, BSM biocomposite, control resin and control composite were investigated and compared to a positive reference, cellulose. Results showed that over a period of 55 days the BSM biocomposite showed 17.6% biodegradation compared to 8% with the control composite. No difference in biodegradation between the BSM bio-resin and the control resin was recorded. BSM biocomposite was proposed as a potential replacement to synthetic composites that contribute to the environmental landfill problems. The main contribution of this research is the use of the reinforcement and matrix from the same natural source. An enriched understanding of the synthesis, characterization and performance of the banana sap based bio-resin and biocomposite for the use of non-functional motor vehicle components is the key outcome of this investigation.

published_or_final_version / Public Administration / Master / Master of Public Administration

Submitted in partial fulfillment of the requirements for the degree of Masters in Technology: Business Administration, Durban University of Technology, 2007. / Unsafe incidents are a regular occurrence in the chemical industries, which have resulted, in some cases in the catastrophic destruction to the environment and loss of life. Major global organizations have shut down after experiencing fatal unsafe incidents as in the case of Union Carbide. This organization was closed after the Bhopal incident in India, in 1984, which claimed the lives of a-bout three thousand residents (see appendix d). In this study, the safety and operational risks at a selected chemical company in Durban are researched. This study looks at the huge number of unsafe incidents in a three year period, from (2003) to year (2005), that occurred at this organization. The objective of this study is to identify the variables that contribute to the high number of unsafe incidents within the organisation. The study will focus on the relationship between staff perceptions and management's assumptions of these contributory variables. The sub-objectives of the study are: o To ascertain staff perceptions of the contributors to the incidents and unsafe working conditions; o To determine if management is accurate in their assumptions of the causes for the incidents; and o To determine relationships between staff perceptions and actual causes of the incidents. The contributors were themed in the study in the following manner: o Behaviour and attitude; e Communications; e Plant and equipment; e Training and development; o Planning and workload; o Safety aspects; and e Other related aspects. Implementing the recommendations made will assist in reducing the number of unsafe incidents and make the organization a safer place for all stakeholders. / M

As proposições deste trabalho tiveram como objetivo fundamental orientar e/ou melhorar um sistema organizado de RSS (Resíduos de Serviços de Saúde), em qualquer estabelecimento gerador, com a finalidade de controlar, reduzir com segurança e economia, os riscos associados aos RSS. Para o desenvolvimento de tais aspectos, foi escolhido o Hospital Unimed, unidades I e II, por ser de porte médio. No desenvolvimento do trabalho, foram considerados três aspectos fundamentais: a organização do sistema de manuseio dos resíduos sólidos, os aspectos técnicos-operacionais, os recursos humanos necessários, determinando assim responsabilidades bem definidas com o intuito de reduzir ao máximo os riscos para a saúde e meio ambiente, atendendo as especificações exigidas pela legislação e colaborando assim com toda a comunidade para uma qualidade de vida cada vez melhor. / The proposals of this work had as fundamental objective to orientate and/or to improve a system organized by HSW (HeaIth Service Wastes), in any generator establishment generated with the aim of controlling, reducing with insurance and economy the risks linked to HSW. To deveIopment of such aspects, Hospital UNIMED was chosen, Units I and lI, because it is a medium size hospital. In the development of this work, three fundamentaIs aspects were considered: The organization of the handIe system of the solids wastes, technical - operational aspects, the human resources necessaries, so determining well defined responsibiIities with the objective of reducing at rnaximum the health and environmentaI risks, taking into consideration the specifications demanded by the legislation and collaborating with all the community for a much better quality of life.