Theses for the College of Engineering & Mines

Recent Submissions

  • The effect of ultrasound on polycyclic aromatic hydrocarbons in aqueous media

    Wheat, Patrick E.; Tumeo, Mark; Brown, Edward; Johnson, Ronald; Reichardt, Paul; Tilsworth, Timothy (1992)
    Polycyclic aromatic hydrocarbons (PAHs) are common environmental contaminants which pose a potential threat to human health and environmental quality. An investigation to determine the ability of ultrasonic radiation to desorb PAHs adsorbed on the surface of solid substrates and to chemically alter these chemicals in aqueous solutions and suspensions has been conducted. The data indicate that enhanced transport of adsorbed PAH from a glass surface can be induced by treatment with ultrasonic radiation of varying intensities. Furthermore, chemical alteration can be induced under intense (147 watts/cm$\sp2)$ ultrasonic treatment. The extent of reaction is a function of irradation time at this ultrasonic intensity. Reaction products from ultrasonic treatment of aqueous solutions of biphenyl, analysed by gas chromatography (GC) and mass spectrometry (MS), include ortho-, meta-, and para-(1,1 biphenyl) -ol. The principal product from ultra-sonic treatment of aqueous phenanthrene appears to be a phenanthrenediol. The use of ultrasound to treat PAH contaminated aqueous solutions in tandem with other methodologies appears promising. However, the toxicity of reaction product mixtures produced by ultrasonic treatment remains to be determined.
  • Micro Scale Analysis Of Fluid Flow And Diffusion In Coarse Grained Porous Media

    Fourie, Walter Johannes; Barnes, David L. (2011)
    X-ray computed tomography and finite element analysis were used to visualize the internal geometry of porous media and calculate the hydraulic conductivity and the diffusion of a dissolved species through the media. The results were compared to laboratory generated results. The calculated hydraulic conductivity showed good agreement with the laboratory results, over-predicting the laboratory results with only 12.5%. Comparison of the calculated results with the Kozeny-Carman equation showed that the Kozeny-Carman equation over-predicted the laboratory results between 62% and 740% depending on the formulation used. The tortuosity and specific surface area showed the highest correlation in predicting the difference between the Kozeny-Carman equation and the modeling results, while the porosity showed the greatest influence in determining the magnitude of the hydraulic conductivity as calculated by the Kozeny-Carman equation. The calculation of the diffusion of potassium iodide through ceramic disks and sandstone showed accurate prediction of the concentration in the receiving cell for the length of the experiment (35 days) for one of the ceramic disks and the sandstone. The other ceramic disk showed accurate prediction up to 20 days, after which it deviated. The results from the study indicate that the diffusional tortuosity and the hydrodynamic tortuosity differ in magnitude, and that they can not be used interchangeably, since (1) the ceramic disks showed the closest prediction to the laboratory results when the diffusional tortuosity is used, rather than the hydrodynamic tortuosity, and when it enters the equation to the first power; and (2) the sandstone showed the closest prediction to the laboratory results when the diffusional tortuosity is used, and when it enters the equation to the second power. Broadly speaking, the results from this study show that the micro scale analysis of porous media allows the accurate calculation of macro scale parameters.
  • Test

    Chisum (2018)
  • TEST 12/5/17

    CHISUM (2017-12)
    TEST
  • TEST 10/18/17

    CHISUM; Chair; Committee Member 1; Committee Member 2 (2017-10-18)
    TEST 10/18/17
  • TEST Older Theses Not Clearly Affiliated with a Current College 9/25/17

    CHISUM (2017-09)
    TEST Older Theses Not Clearly Affiliated with a Current College 9/25/17
  • TEST College of Engineering & Mines 9/25/17

    CHISUM (2017-09)
    TEST College of Engineering & Mines 9/25/17
  • The physical and chemical effects of mid-winter pumping of tundra lakes on the North Slope, Alaska

    Miller, Derek Dan (2005-05)
    Tundra lakes are a valuable freshwater resource on the Alaskan Arctic Coastal Plain and are of increasing relevance as the petroleum industry in Alaska continues to rely on the freshwater resource to support exploration and production activities. An investigation of the physical and chemical effects of mid-winter pumping activities was conducted at four tundra lakes on the Alaska Arctic Coastal Plain during the 2002-2003 and 2003-2004 winters. The purpose of the study was to determine the impact of removing water from tundra lakes for the construction of ice roads and pads. Measurements of water surface level, specific conductance, temperature and dissolved oxygen were recorded in near real-time, providing an opportunity to detect immediate and cumulative responses from pumping activities. Water quality variables and recharge processes were also examined to further determine the impacts of mid-winter pumping activity. In examining and characterizing the effects of the water withdrawal, changes in water surface level were detected but no chemical or thermal differences were detected due to pumping.
  • An experimental investigation of natural freezing and biopolymers for permeability modification to reduce the volume of dense non-aqueous phase liquids in groundwater

    D'Cunha, Neil John (2004-12)
    Dense Non-Aqueous Phase Liquid (DNAPL) contamination is one of the major environmental concerns today. DNAPL can remain in significant quantities as residual contaminants in the low permeability zones even after the bulk phase has been removed. As the drive fluid sweeps through the aquifer it follows the path of least resistance, which is the high permeability zone. Thus the contaminants trapped in the low permeability zones remain as residuals and serve as a source for prolonged contamination. Conventional remediation techniques are ill-equipped to deal with the heterogeneities of the aquifers. Various techniques to enhance the efficiency of the conventional methods are tried without significant success. Reducing the temperature of soil formations can modify aquifer flow paths. The natural freezing of soils in winter may be used effectively to modify the flow paths. In summer, permeability modification can be accomplished by emplacement of microbial polymer gels. In this thesis, we have investigated using a laboratory scale one dimensional column experiment, a novel technique to reduce the volume of residual DNAPL using a combination of natural freezing in winter and biopolymer in summer.
  • Performance analysis for remote power systems in rural Alaska

    Chubb, Tyler (2004-12)
    Due to the logistical difficulties involved in maintaining a rural Alaskan power generation facility, it is extremely important that the system function as efficiently as possible. Presently, many rural generation systems are not equipped with automated monitoring that enables knowledgeable personnel to view the performance of the system from a distant location. Consequently, system deficiencies resulting in increased fuel consumption and operating expense often go unnoticed as do potential system improvements. This thesis describes the design and implementation of a sophisticated monitoring system that consists of measurement sensors connected to an internet enabled data recorder. The monitoring system was used to continuously record the various forms of energy entering and leaving a diesel generator operating on the UAF campus. While in operation, the monitoring system was instrumental in identifying several measures that could be taken to improve the operating efficiency of the generator and also provided sufficient means to examine the economic feasibility of their implementation. The measures that were examined included heat recovery, conditioning of output power, and improvement of operating techniques.