Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains ix, 67 p. : ill. (some col.), col. map. Includes abstract. Includes bibliographical references (p. 64-67).

Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains xi, 79 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 42-47).

Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

Thesis (M.S.)--Baylor University, 2006. / Includes bibliographical references (p. 185-188).

Thesis (M.S.)--Ohio State University, 1986. / Includes bibliographical references (leaves 77-84). Available online via OhioLINK's ETD Center.

Thesis (Ph. D.)--University of Texas at Dallas, 2007. / Includes vita. Includes bibliographical references (leaves 80-86)

The flow of particulate suspensions and brines in porous media is encountered in a wide range of industrial situations such as oil production, soil erosion, and ground water pollution and in the operation of filter beds. Three major classes of such problems are addressed in this thesis, namely particle movement, scale formation and filtration. Particle movement and scale formation are known to be serious problems in oil reservoirs where incompatible brine is brought into contact with the formation. Dramatic reductions in permeability are observed in such cases due to the release of fine particles that subsequently plug flow channels downstream. This study deals with an experimental and theoretical study of formation damage resulting from particle movement and scale formation in porous media. An experimental investigation was undertaken to look into the possible causes of the injectivity loss in a typical Iranian oilfield. Sets of experimental investigations were undertaken with different objectives in mind. Glass and sand bead packs were used to test the experimental set up and to observe the general behavior of fine particle movement and scale formation in porous media. The experiments were conducted with injection rates from 25 cm3/min to 100 cm3/min. Particles of alumina oxide were suspended in the injected water to simulate fine particle migration in porous media. The particles were injected at concentrations ranging from 500 ppm to 2000 ppm. It was observed that the build-up of flow resistance was mostly due to frontal face plugging. Alumina particles were added to the glass beads to study the effect of particles initially present in the glass bead pack. A mathematical model is presented that simulates the porosity impairment by particle movement. This model, which is based on the mass balance of particles flowing through the porous media, at first, proposes an overall equation to determine the porosity and by a special mechanism it can predict the overall change in porosity. The equations are quite general and can be used to model the permeability reduction for any given pore or particle size distribution. Also this study aims to investigate the calcium sulphate and calcium carbonate scaling in a porous medium to discover its possible effect upon the permeability of the porous medium. The information on the effect of scale deposition is obtained experimentally by flooding porous medium with incompatible brines. The experimental data are used to develop and validate models for predicting the permeability decline caused by scale. The model is intended to provide a link between what is known or can be assumed about brines in an oil reservoir. A computer program was developed which can predict the scaling tendency of the sulphate minerals and calcium carbonate, in water disposal wells, water injection systems, surface equipments and facilities that commonly form scale. This program is based on the latest correlations of experimental data relating to North Sea and Iranian oilfields. It is used to determine the degree to which brine becomes supersaturated with a scale forming mineral under specified conditions. Processes capable of creating supersatuartion in oilfields are described and it is shown that the distribution of scale depends on the process involved.

No description available.

A mathematical model of maximizing the present-value of the groundwater reservoir is developed. According to it the optimal condition of the water use is: to ration the water in a way which makes the marginal net rent to the water equal to the marginal user cost each year. The model is valid for every amount of recharge. The rent function is derived from the agricultural production function and it is based on the main assumption that diminishing return to the water exists. Using the rent function the present-value expression for the reservoir has been established. It is differentiated in respect to the water used - the chosen independent variable of the rent function. In this way the result mentioned above has been achieved. The optimal sequence of the water use - which maximizes the present-value of the reservoir - has been calculated by salving the set of equations of the optimal conditions of each year. Both the optimal sequence of the water use and the user cost have been calculated explicitly and expressed in formulas by measurable parameters. It is argued that only a profit maximizing sole owner for whom the user cost is meaningful would use the water in the optimal sequence. If the reservoir is a common property resource a non-optimal water use would be practized. This non-optimal sequence of the water use is calculated by solving the set of equations of the non-optimal condition of the water use of each year. Considering the user cost zero the condition of the water use became: to use the quantity of water every year which makes the marginal net rent equal zero. The optimal condition of the water use developed in this work, which says marginal rent should be equal marginal user cost made possible to establish the non-optimal condition of the water use by turning the user cost to zero. The non-optimal water sequence is expressed too in an explicit formula by measurable parameters only. It is compared to the optimal water sequence. Also life-time of the reservoir and its final depth are compared for the cases of optimal and non-optimal water use. In the case of optimal water use (sole ownership) the water use is more gradual, the economical life of the reservoir is longer and its final depth is less deep than in the case of the non-optimal water use. A numerical example at the end of this work shows that - in these circumstance - the user cost has a significant magnitude. / Arts, Faculty of / Vancouver School of Economics / Graduate

This thesis describes the development of a method for determining the most efficient way to operate an upstream flood control reservoir for maximum flood peak reduction at a downstream point. Linear programming is used as the optimization technique. A simplified case is studied, namely that of a single storage reservoir approximately 500 miles upstream from the area to be protected. A channel routing method which was linear was required for use with linear programming. For this reason a Muskingum type channel routing method was chosen. The results for the three years that were studied are presented in graphical form. They indicate the extent that the downstream peak could be reduced and the operation of the upstream reservoir which would be required to bring about this reduction in peak flow. Procedures for extending the technique to more complex systems and possible applications of the method are discussed. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate