Landfill leachate, the liquid discharge from Municipal Solid Waste (MSW) landfills, is the combination of the surface runoff and ground water that percolates through the waste and the liquid contained in the waste itself and is considered to be toxic and presents a potential harm to the environment. Raw leachate contains high concentrations of biodegradable and non-biodegradable carbon as well as high concentrations of ammonia nitrogen. Traditionally, landfill leachate has been treated biologically through aerobic processes which reduce the biological carbon to carbon dioxide and biomass (bacterial growth) and ammonia nitrogen to nitrates. Unfortunately this is not sufficient to protect the environment from harm. It is necessary to further treat the leachate anaerobically to transform the nitrates to elemental nitrogen which is removed from the leachate as nitrogen gas. Biodegradable carbon is often the rate limiting substrate as carbon is consumed during the preceding nitrifying phase. Biodegradable carbon can be supplemented through the addition of methanol, at great expense Leachate from the Mariannhill Landfill site is currently treated aerobically in a sequencing batch reactor where nitrification is achieved. The nitrified leachate is then used as a dust suppressant on the current site. It is anticipated that in 2012 the Land fill site would have reached capacity thereby eliminating the need to irrigate and leaving the site with an excess of nitrified leachate that will present an environmental risk. The denitrifying performance of raw commercial garden refuse, pine bark and composted garden refuse as a growth medium and carbon source was investigated through the establishment of batch and column tests. CGR Raw proved the most successful of the three growth media, achieving full denitrification at a loading rate of 1700 mg NO3-N/kg of substrate/day. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2010.

A dissertation submitted to the Faculty of Health, in fulfilment of the requirements for a Master's Degree in Technology: Environmental Health, Technikon Natal, 2001. / The purpose of this study was twofold. Firstly, the effect of the social dimensions of households on solid waste practice was investigated in order to examine relationships between socio-economic status and current solid waste practices. Current perceptions and solid. waste practices of households with different socio-economic backgrounds were assessed and compared to explain the influence of socio-economic factors in the planning and operation of a solid waste management system in developing urban areas. Secondly, a waste stream assessment was carried out to examine waste generation and composition trends among different social status residential urban areas. The generally poor state of solid waste services in most developing urban areas in South Africa and the chronic absence of data on domestic solid waste practice in the study area prompted this research initiative. A case study in Umtata involving three residential areas with different socio-economic status was used to assess and explain trends in solid waste practice and contributory factors to variations between different households amongst developing communities from a socio-economic perspective. Data were collected by a waste stream assessment survey involving measuring waste generated from the selected households and analysis of its composition. The waste stream assessment was complemented by a descriptive survey questionnaire, administered by means of personal interviews to each householder or resident in randomly selected households situated in the study area. The survey provided baseline information on solid waste practices and showed that local conditions were unique and thus require a local solution to the solid waste problems. The study showed that the understanding of the relations within households is vital for planning appropriate, effective and sustainable solid waste service programmes /systems. Gender relations, age, educational status and income are significant factors to be considered in planning and effectively operating solid waste management plans. / M

Thesis (Master of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2017. / Pre-treatment of wastewater such as that from poultry slaughterhouses, which contains fats, oil,and grease (FOG) is necessary prior to the primary biological treatment of the wastewater to meet legislated discharge standards and to prevent environmental pollution. Physico- chemical pre-treatment is often applied to remove FOG in poultry slaughterhouse wastewater (PSW) before biological treatment. These pre-treatment methods, in particular physical pre- treatment systems, use synthetic chemicals, known to cause environmental contamination challenges, with FOG being inefficiently removed in certain instances. Biological techniques such as bio-delipidation using enzymatic catalysis for the pre-treatment of FOG-laden PSW could enhance the efficiency of the downstream biological treatment processes. This research focused on further bio-delipidation of PSW pre-treated with a dissolved air flotation system (DAF) for FOG removal using microbial lipases from bacterial strains isolated from the PSW itself. Bacterial strains (n = 2) isolated from the PSW and screened for their potential to produce lipases were found to have a higher bio-delipidation potential when compared to other isolates (n = 18). Both isolates were identified using 16s rRNA as Bacillus sp., i.e. both Bacillus cereus AB1 (BF3) and CC-1 (B3O). These isolates were used to produce lipases, whereby are sponse surface methodology (RSM) was used to optimise pH (4-8) and temperature (30-60°C) as critical production conditions. achieving an optimum lipase production was achieved, with activity of 11.25 U/mL at 60°C, a pH of8 for BF3, and 15.50U/mL at 45°C and pH of 8.8 for B3O respectively, after 72 hours of bioreactor operation. The enzymes produced from both isolates were partially purified using a Bio-Rad size exclusion chromatography column (Bio-Gel® P-60) prior to use in subsequent experiments. The presence and activity of lipase were further determined using p-nitrophenyl acetate (p- NPA) as a substrate with the functionality of the semi-purified enzymes being characterized by optimizing the conditions in which the enzymes were required to function. Lipase activity was enhanced by Mg2+ while Fe2+, Na+, K+, Ca2+ were observed to have an inhibitory effect on the enzymes from both strains. Similarly, reduced stability of the lipases in organic solvents, namely toluene, methanol, and isopropanol, was also established. Additionally, detergents, Triclosan (TCS) (5-chloro-2-(2,4-dichlorophenoxy-phenol) and trichlorocarbonilide (3,4,4- trichlorocarbonilide)(TCC), usually found in PSW as antimicrobial and disinfectant agents to sanitise poultry product processing facilities, were used assess the activity of the enzyme in their presence at a concentration of 30% (v/v) (although these anti- microbial agents are used in minute quantities in cleaning products). The lipases from isolate BF3 maintained an activity of 91.43% and 81.36% in the presence of TCS and TCC, while that of B3O enzyme had 85.32% and 73.91% acitivity, when compared to the reference (control) experiments. The bio-delipidation efficacy was studied under varying pH and temperature conditions using DAF pre-treated PSW, observing a further removal efficiency of fatty acids from the protein- laden PSW at different pH and temperature. Bio-delipidation was found to be largely influenced by pH, as a pH below 7 and above 10 at 40°-45°C, calculated in the bio- delipidation efficiency reduction to below 50%. The temperature range mentioned, i.e 40°- 45°C, had a positive effect on further deffating of the protein-rich DAF pre-treated PSW, as high removal efficiency was observed at this temperature range. This could be due to the characteristic of the enzymes used,or the formation of stable FOG agglomerates and/oremulsion. Overall, a DAF effluent containing residual FOG and proteins was bio-delipidated effectively using enzymes from the PSW isolates, achieving further removal of FOG and proteins by 64.35% to 80.42%, culminating in tCOD reduction and reduced PSW turbidity, further resulting in improved wastewater quality characteristics meeting disposal standards. This study demonstrated that sequential DAF pre-treated PSW bio-delipidation has the potential to enhance the efficiency of downstream biological anaerobic treatment processes for PSW by further reducing residual FOG from a DAF system.

Uranium mill tailings from the Ranger mine, located in the Alligator Rivers Region of the Northern Territory, Australia, were examined to assess the effects of weathering and diagenesis on their long-term geochemical stability. Run of mill uranium tailings are a complex heterogeneous mixture of lithogenic ( primary gangue minerals and weathering products ) and secondary ( components that form during milling ) minerals, residual process chemicals and biogenic ( products of biological activity ) phases. Following transfer to the tailings storage facility, post depositional reactions alter the mineralogical and hydrochemical characteristics of the tailings solids and pore waters in accordance with weathering and diagenetic processes. In this thesis, a detailed examination of tailings cores and pore waters, kinetic column test work and geochemical modelling was combined with results from earlier studies to examine the key processes governing the geochemical stability of the Ranger tailings. Conclusions drawn from the work clearly demonstrates that the solid state speciation and mobility of metals and radionuclides in the tailings pile are governed by the processes of oxidative dissolution of sulfide minerals, weathering of phyllosilicates and organic matter diagenesis. The processes are spatially dependent, evolve over time and are influenced by the following key factors : 1. Tailings water content or degree of saturation ; 2. The nature and content of organic matter in the tailings ; 3. Redox potential of the tailings solid - pore water interface ; and 4. The specific reactivity of precursor minerals ( primary / secondary ) from the milling process and pore water solutes. Combined, these processes lead to the formation of authigenic minerals, which control the solubility of pore water constituents. These mechanisms will also have a profound impact on the long-term geochemical stability of the tailings pile and, as such, will need to be taken into account in the design, management and closure of the final tailings repositories at the Ranger site. / Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2004.

This study had two purposes: to determine solid waste management needs of residents and organizations of the San Xavier District Indian reservation near Tucson, Arizona; and to develop a solid waste management plan to be recommended to the San Xavier District Tribal Council. A solid waste generation study compared the daily per capita solid waste generated over one week by 25 Indian households, 15 Adult non-Indian households and 15 Family- Adult non-Indian households on the district. An analysis of variance showed that the differences in daily per capita solid waste generation among the three groups were not statistically significant at the .05 level, and a t-test showed that differences between the Indian residents and the non-Indian residents considered as one group were not statistically significant at the .05 level. The overall daily per capita solid waste generated by all groups, 1.71 lbs/day, was less than half of the national average of 3.5 lbs/day. The Adult non-Indian households had the highest daily per capita solid waste generation (1.96 lbs), while the Indian and the Family-Adult non-Indian households generated a similar amount of solid waste daily per person (1.67 and 1.64 lbs respectively). Four alternative solid waste management proposals were developed: (1) a tribal-operated solid waste management and disposal service serving all residents and most organizations on the San Xavier district and trucking solid wastes off the reservation; (2) the same as Alternative One except that disposal would be in an 8.24 acre landfill to be constructed by the tribe on the district; (3) contracting waste pickup and disposal to an outside waste management company; and (4) the same as Alternative One except that commercial organizations on the district would not be served. Evaluation of the four proposals showed that Alternative One best fulfilled the objectives of the san Xavier District Tribal Council, and that alternative was chosen for recommendation to the San Xavier District Tribal Council. It was also recommended that a recycling proposal by U.S. Recycling Industries be accepted. / Graduation date: 1991

Thesis (Professional Degree)--University of Missouri, School of Mines and Metallurgy, 1930. / There is no leaf number 94 in the thesis. The author mistakenly omitted it. The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed December 23, 2009) Includes bibliographical references (p. 158) and index (p. 159-169).

published_or_final_version / Public Administration / Master / Master of Public Administration

No description available.

Final Report, Investigations on the Subsurface Disposal of Waste Effluents at Inland Sites / Grant No. 14-01-0001-1805 / United States Department of the Interior, The Office of Saline Water / By L.G. Wilson, Hydrologist, The Water Resources Research Center, The University of Arizona / February 1971.

No description available.