Thesis (M.Sc.)--Memorial University of Newfoundland. / Typescript. Restricted until May 1997. Bibliography: leaves 100-104. Also available online.

Thesis (M. Eng.)--Memorial University of Newfoundland, 1997. / Bibliography: leaves 95-101.

Thesis (M.Sc.)--University of Hong Kong, 1994. / Includes bibliographical references (leaf 63-64). Also available in print.

Thesis (M.Sc. Earth Sciences)--University of Waikato, 2006. / Includes bibliographical references (leaves 134-147)

The objective of this research was to determine if mature landfill leachate could be treated to a level so that it was safe to discharge to the environment. The treatment method was an Advanced Oxidation Process. The process utilized Titanium Dioxide and UV. Three different reactor types were used, falling film, flow through and falling film + Electron Magnetic Oxygen Hydrogen (EMOH). To improve removal pre-treatment with titanium dioxide settling were conducted in conjunction with treatment in a reactor. The best removal was obtained with pre-treatment with titanium dioxide settling, followed by the falling film + EMOH reactor. In 8 hours, removal was 63% for COD, 53% for ammonia, 73% for alkalinity and 98% for calcium hardness. The kinetics found in this experiment show that full treatment times for safe discharge vary between contaminates. For complete removal of all tested contaminates to safe discharge regulations requires 185 hour of treatment. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection

published_or_final_version / Civil Engineering / Doctoral / Doctor of Philosophy

This research involves the evaluation of municipal landfill leachates for specific hazardous compounds in an effort to qualitatively determine the potential for groundwater contamination. Leachate samples from five landfills were evaluated for thirteen EPA priority pollutants using gas chromatography. In addition, samples were analyzed for total organic carbon (TOC) and total organic halide (TOX). A solids analysis was performed on refuse excavated from one landfill. This analysis included organic halide determination of interstitial liquids, and a total halide determination for each solid sample. A solids/liquid partition coefficient was calculated from the results. The literature review includes a detailed section outlining the biological degradation of hazardous organic compounds in anaerobic environments similar to conditions found in landfills.

Present day society generates large volumes of waste that present an environmental hazard when disposed of in landfills. As our population grows, so does the volume of waste generated and hence the threat to our environment. One method of reducing harmful emissions in landfills is the mechanical-biological pretreatment of waste prior to landfilling. The purpose of this dissertation is to investigate the degree of stabilization of waste in shallow landfills (simulated by test cells) with particular focus on biogas production and quality. Municipal waste was composted in aerobic, open windrows for periods of eight and sixteen weeks. Five test cells, designed and operated according to the PAF model (Pretreatment, Aeration and Flushing) were constructed at the Bisasar Road landfill site. These cells were used to simulate large scale municipal landfill sites. They were filled with fresh and pretreated waste and were used to monitor the dynamics of prolonged aeration and degradation of waste over a period of six months. The cells were monitored on a weekly basis while being aerated. Two flushing events were conducted at the beginning of the passive aeration. Gas emissions were also monitored by recording the methane, carbon dioxide and oxygen volumes per volume of air in probes strategically placed in each cell. These results were then analysed to assess the effect of mechanical-biological pretreatment of municipal solid waste on the emission quality of sanitary landfills and the appropriateness of prolonging the aeration in shallow landfills, as often used in sub-tropical countries. It was found that the design of the test cells was appropriate for the landfilling and stabilization of waste that was aerobically treated. After six months in the test cells, analysis of the waste from each cell showed that the waste was completely degraded. The PAF model, when applied to shallow landfills, is very effective in stabilising waste and would be appropriate for a sub-tropical climate. Waste that is pretreated, placed in shallow landfills, initially flushed and then aerated over a six month period was fully stabilized. The requirement for such treatment would be relatively small amounts of waste, a wet climate and the availability of open space for shallow landfills. This method, therefore, would be very appropriate in a South African context. The major problem with this method may be the generation of large quantities of leachate which will have to be treated and disposed of in an environmentally safe manner. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, 2006.

This research was carried out at the Bisasar Road Landfill site, Durban, South Africa, / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2007.

A relatively new concept of Municipal Solid Waste treatment is known as bioreactor landfill technology. Bioreactor landfills are sanitary landfills that use microbiological processes purposefully to transform and stabilize the biodegradable organic waste constituents in a shorter period of time. One of the most popular types of bioreactor landfills is the landfill with leachate recirculation. However, it is observed that ammonia rapidly accumulates in landfills that recirculate leachate and may be the component that limits the potential to discharge excess leachate to the environment. In the facultative landfill, leachate is nitrified biologically using an on-site treatment plant and converted by denitrifying bacteria to nitrogen gas, a harmless end-product. In this research, three pilot-plant scale lysimeters are used in a comparative evaluation of the effect of recirculating treated and untreated leachate on waste stabilization rates. The three lysimeters are filled with waste prepared with identical composition. One is being operated as a facultative bioreactor landfill with external leachate pre-treatment prior to recirculation, the second is being operated as an anaerobic bioreactor landfill with straight raw leachate recirculation, and the third one is the control unit and operated as a conventional landfill. Apart from environmental restrictions, geotechnical constraints are also imposed on new sanitary landfills. The scarcity of new potential disposal areas imposes higher and higher landfills, in order to utilize the maximum capacity ofthose areas. In this context, the knowledge of the compressibility of waste landfills represents a powerful tool to search for alternatives for optimization of disposal areas and new solid waste disposal technologies. This dissertation deals with and discusses the environmental and geotechnical aspects of municipal solid waste landfills. In the Environmental Engineering area, it compares the quality of the leachate and gas generated in the three lysimeters and discusses the transfer of the technology studied through lysimeters to procedures for full-scale operation. In the geotechnical area, this dissertation discusses the compressibility properties of the waste and provides a state-of-the-art review of MSW compressibility studies. It also evaluates the compressibility of MSW landfills for immediate and long-term settlements and proposes a new model for compressibility of waste landfills.