Thesis (M. Env. St.)--University of Adelaide, Centre of Environmental Studies, 1985. / Includes bibliographical references.

Thesis (M.S. - Renewable Natural Resources)--University of Arizona, 1985. / Includes bibliographical references (leaves 74-75).

Thesis (M.S. - Renewable Natural Resources)--University of Arizona, 1985. / Includes bibliographical references (leaves 108-109).

Thesis--Auburn University, 2009. / Abstract. Vita. Includes bibliographical references (p. 91-87).

Thesis (Professional Degree)--University of Missouri, School of Mines and Metallurgy, 1937. / The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed June 15, 2010) Includes bibliographical references (p. 73).

No description available.

The North American landscape changed tremendously following the arrival of European settlers. Before European arrival, New England’s landscape was primarily forested. As Europeans moved inland from the eastern seaboard, they cleared the forest for settlement and agricultural use. Eventually the Industrial Revolution made a different kind of mark on the landscape. Starting in the late 1790s, the textile mill industry developed throughout the region. Mills were located along swift moving rivers, which later produced power when dams were created along them. Following the early 1900s mill production decreased, leading to the abandonment of many mills and their adjacent dammed mill ponds. However, the environmental changes wrought by the mill ponds still exist in New England’s landscape. Large volumes of fine sediment have since built up in some of these former mill ponds and concerns about the sediment and water quality have become widespread. Today many former textile mill rivers throughout the U.S and Europe have been tested in an attempt to determine current contamination levels and to apply appropriate strategies if necessary to reduce pollutants to acceptable levels. Little is known about water and sediment quality of the former mill ponds in Scituate, Rhode Island. This research sought to address this problem by conducting trace metal testing of two mill ponds in the Scituate River Watershed: Peabody Pond and Jordon Pond. Results revealed that both ponds contain pollutants from present and past sources, but that contemporary land use practices may be the most harmful to water and sediment quality. Existing mill metal piping left on the landscape and present-day motorways and urban runoff contain large quantities of suspended solids such as copper, lead and zinc with lead showing the highest concentration levels of all metals tested. This research demonstrates that our past landscape activities, specifically New England’s historic textile production, still influences present environmental conditions, and that as human activities on the landscape change, so do threats to environmental quality.

Digitized by Kansas Correctional Industries

Wastewater stabilization ponds have gained popularity as a means of secondary wastewater treatment because of their low cost and simplicity of operation and maintenance, in addition to several other advantages. However, the presence of algae in the effluent from facultative ponds may cause undesirable environmental impacts, such as DO depletion or eutrophication, in water bodies to which this effluent is discharged. Thus, regulations and/or the adverse environmental impacts of effluents containing algae sometimes necessitate reduction or removal of algae from pond effluents. Many methods have been used for the purpose of removal of algae from wastewater stabilization pond effluent. Upflow rock filtration and coagulationsedimentation have been investigated in this research. In the past, mechanisms of removal of algae in rock filters and factors that affect the removal process have not been well explained. Design of these filters has not been related mathematically to the operating variables. Three pilot rock filters were built for the purpose of this research. The first filter was filled with rock of 1 cm average diameter, the second and third filters were filled with 5 cm and 10 cm average diameter rock, respectively. Five different hydraulic loadings were applied to these filters, with variable influent characteristics and under different environmental conditions. The results of this research have shown that gravitational settling and hydrodynamic forces are the most important mechanisms affecting removal of algae in upflow rock filters. Also, a method of design of unisize-media upflow rock filters for removal of algae from facultative pond effluent has been established. The cost of coagulant has been the main disadvantage of the process of coagulation-sedimentation for algae removal from wastewater stabilization pond effluent. In this research, jar tests were carried out to determine the effect of settling time and/or addition of kaolinite or bentonite with the primary coagulant, alum, on the optimum dose of this primary coagulant required for removal of algae from facultative pond effluent. Both increase in settling time and coagulant aids, namely kaolinite and bentonite, have reduced optimum alum dose. Kaolinite and bentonite, applied as low-cost primary coagulants, were also effective in removing algae from facultative pond effluent. From the very limited experiments carried out at the end of this research, it was shown that crossflow microfiltration has some potential as a process for algae removal from facultative pond effluent. A mathematical model has been developed in this work to describe the eutrophic state of King Talal Reservoir in Jordan. The model predicts that even elimination of phosphorus from the effluent of Al-Samra Wastewater Stabilization Ponds will not bring the reservoir into an oligotrophic state.

The principal objective of the present thesis has been to develop a methodology for the simulation and optimization of electric power generation by solar ponds. / A mathematical model for the analysis of the economic performance of a solar pond electric power system using a heat engine is developed. A salient feature of this model is a simple method for the analysis of a Rankine cycle. Other features include a mathematical model of the solar pond, of the energy exchange properties of the heat exchangers, as well as of the power required by the circulating pumps. The net electric power is expressed in terms of the thermodynamic properties of the organic working fluid, the temperatures of various thermodynamic states, the flow rates, the temperature and geometry of the solar pond, and the local climatic conditions. The system sizing and operating conditions which minimize the cost per kilowatt hour of electric energy is then determined through an optimization routine. / The optimal storage depth and heat extraction scheduling are obtained by a semi-analytical method as well as a discrete optimal control technique. The possibility of an ice storage to act as a cooling source for an SPPP has also been investigated, which showed considerable improvement in the system's efficiency and reduction of electric energy cost. / The possibility of making the NCZ of a solar pond float over a layer of fresh water has been investigated. The economical feasibility study of the concept for electric power generation was achieved using the model developed earlier. / The thesis finally examines the means of enhancing the thermal storage under a solar pond by circulating LCZ brine through a network of buried horizontal pipes in the warmer part of the year. This heat stored can be used for the operation of a heat engine during the winter time if the LCZ brine is then used as a heat sink rather than a heat source. / The present thesis has shown that the commonly held belief that SPPP can only function at acceptable efficiencies under semi-tropical conditions of SPPP in northern climates resulted in electric energy costs of 8.5 (CENTS)/KWh which is comparable with that of estimated by Israelis for an SPPP in semi-tropical conditions.