No description available.

The purpose of this study is to investigate the possibility of using the Bleached Kraft wastewater sludges as a sealant to a permeable soil structure which could contain these liquids. The sludges used are either self-contained in wastewater, produced from treatment processes, or from the addition of chemical coagulant to the wastewater. / The mechanisms of the sludge sealing phenomena which were investigated individually are divided into physical, physico-chemical, biophysical and bio-physico-chemical types of seals. Coarse sand #24 was found suitable for this sealing study as a particle size cut. Among the types of sealings studied, the bio-physical type of seals is the most effective. The physico-chemical type of seals is effective in the initial stage of sealing. The coefficient of the permeability is reduced from an average of 6.4 x 10('-2) cm/sec to 1.0 x 10('-6) cm/sec in a period of 24 hours, with a risk of leakage of less than 1% of the total effluent. / A long-term stability of using sludges as a liner to the wastewater pond has become a substantial issue. Alum was originally chosen as an effective coagulant for forming a layer of sludge for physico-chemical types of sealing. However, after the stability analyses, one finds that alum sludge is not a stable material under commonly-found hydrostatic pressures and high pH ranges. The results of the research shows that one of the alumino-silicate sludges is much more stable than that of alum sludge. The relatively stable alumino-silicate sludge was obtained from one of the coprecipitations of sodium-silicate and sodium aluminate in a BKME solution. / The economic impact of using alumino-silicate sludge is significant. The cost comparison study shows a cost ratio in the range of up to 1:10 as compared to conventional lining material. The results can be used for the implementation of field work in sludge sealing practice. In addition, this investigation could form an excellent foundation for further studies on other effluents with different parameters.

A two-dimensional hydrodynamic model is used to simulate the flow field and the concentration distribution of a conservative tracer in shallow basins. A series of numerical test are performed to evaluate different numerical schemes and problems which arise for the use of the Second Moment Method (SMM) in diffusion dominated flows are reported. The results of the basin simulations are compared with experimental data. The model predicts the location and the size of the dead zones, bypassing, recirculation, and local concentrations within the basin. The positioning of the inlet and outlet, and the presence of baffles are important parameters for the location and size of dead zones. The model gives results which are in agreement with the experimental data. The results show that the hydrodynamic model is quite powerful in terms of predicting correctly the residence time distribution for ponds of various dimensions and shapes.

Thesis (Ph. D. - Civil Engineering)--University of Arizona. / Includes bibliographical references (leaves 111-116).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1960. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 115-119).

Thesis (M.Eng.)--University of Wollongong, 2004. / Typescript. Includes bibliographical references: p. 193-209.

Thesis (M.S.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on October 30, 2007) Includes bibliographical references.

Salinisation has been identified as a major cause of the progressive deterioration in the public water system in South Africa. To deal with this problem Waste Stabilisation Ponding systems have been used by the Leather Processing Industry as zero-dischaJ;ge wastewater evaporation disposal processes in water-limited inland regions of the country. While effective in the evaporation disposal function these systems are plagued by the generation of serious odour nuisance creating intractable environmental problems relating to adjacent residential communities. High loading to ponds of organic compounds, sulphides and ammonia results in strongly reducing anaerobic conditions prevailing in early parts of pond cascades. These are characterised by bright red colours due to the predominance of purple photosynthetic bacteria. Sporadic micro algal blooms of Spirulina sp. and Dunaliella sp. had been previously noted to occur on the latter ponds in these cascades, and were associated with their conversion to facultative function, with aerobic surface layers, and a marked reduction in odour release. This research programme undertook an investigation of the microbial ecology of a tannery waste stabilisation ponding system to describe factors which give rise to these blooms, and to determine whether microalgal growth may be manipulated to achieve a reliable oxygengenerating capping of the anaerobic ponds. The predominance of near pure cultures of Spin/lina platensis was demonstrated for the blooms and factors restricting its growth in the system were described. These include the interaction of ammonia and sulphide toxic effects and laboratory studies were undertaken to show how effluent loading may be regulated to enable effective growth of the cyanobacterium. At appropriate dilutions of tannery effluent an enhancement of growth was noted, compared to growth in defined mineral medium. An investigation of this phenomenon provided preliminary evidence for organic uptake by the pond micro algae and a possible contribution to heterotrophic nutrition. The manipulation of Spirulina sp. growth in a High Rate Algal Pond raceway was undertaken in outdoor pilot plant studies and the effect of microalgal capping of the anaerobic ponds in the cascade was demonstrated by activating a recycle loop from a blooming facultative pond. Heavy metal contaminants were effectively eliminated by an optimisation of the primary anaerobic pond function and precipitation as metal sulphides. Biomass was harvested and dried, during which a range of methods were evaluated. Toxicological studies were undertaken on the dried biomass using Artemia and chick assays, and feed studies showed its useful application in rations for the abalone Haliotlls midae and rainbow trout Onchorhynchlls mykiss. Based on positive independent assessment of research outcomes, a decision was made by the tanning company operating the Waste Stabilisation Ponding system, to proceed to the construction of a full-scale 2 500 m2 High Rate Algal Pond raceway. This would be used for controlled Spirlilina biomass production to effect a practical capping of the anaerobic ponds in the system, and to evaluate its commercial potential in the feed market. The Advanced Integrated Wastewater Ponding System described by Oswald (1991) provided the conceptual basis for the Algal Biotechnology process development undertaken. The studies of the microbial ecology and the biotechnological potential of this system have shown that a Spirulina-based High Rate Algal Ponding process can be engineered in such a way that saline tannery effluents may be treated to effect a significant reduction in overall pollution load, that biomass may be recovered as a value added product of the treatment process and that the operational performance of Waste Stabilisation Ponding systems, and hence their immediate environment, may be improved by the use of the High Rate Algal Pond as a retrofitted upgrading unit operation.

No description available.

A waste stabilization pond was investigated to determine if there was a health hazard due to contamination of the shore line. Soil samples were taken at various points along the bank and water samples were collected from the pond. Coliform and enterococci counts were made from the samples and were employed in conjunction with observations made of conditions at the sample points to determine if a health hazard existed at the shore line. Three stations were located along the leeward side of the pond. At each station samples were taken in adjacent soil, soil at the water line, water at the water line, water from the pond surface and water from one and one-half feet beneath the pond surface off shore. Using the geometric mean, coliform counts ranked as follows: 1717.7 water sample one and one-half feet below the surface and off shore, 583.9 soil sample at the water line, 79.0 soil on adjacent bank, 20.2 surface water sample off shore, and 11.5 water sample at water line. The high count one and one-half feet below the surface is presumably from the sewage being added to the pond. Low counts were associated with pH values near ten. High counts generally occurred at more neutral pH values of about eight. The counts at the water line are not high enough to indicate the presence of significant concentrations of fecal matter. Also, no fecal matter or other floating matter was observed at the shore line. The counts from the soil on the bank up from the shore line were what would be expected from a similar area excluding the waste stabilization pond. A comparison of the coliform and enterococci counts showed that the enterococci count is approximately one half the coliform count which is in agreement with other investigations (2) and indicates its usefulness as an indicator organism. / Master of Science