<p> Capturing carbon dioxide (CO₂) from stationary sources and injecting it into deep underground geologic formations has been identified as a viable method for reducing carbon emissions to the atmosphere. Sedimentary rocks, such as sandstones overlain by shales or evaporites, are the preferred formations because their morphology and structure provide pore space, and containment for the long term storage of CO₂. Sandstone formations have also served as repositories to migrating hydrocarbons, and are the sites of many oil recovery operations. For many depleted oil reservoirs, secondary waterflooding recovery methods are no longer efficient or economically viable, hence the application of tertiary CO₂ enhanced oil recovery (CO₂-EOR) followed by CO₂ storage is an attractive and cost effective business plan. </p><p> Citronelle Oil Field, located in southwest Alabama, is the largest and longest producing sandstone oil reservoir in the state, having produced more than 170 million barrels of oil from its estimated 500 million barrels of original oil in place, since its discovery in 1955. The field is in the later stages of secondary recovery by waterflooding and daily oil production has declined considerably. The field is comprised of the Upper and Lower Donovan hydrocarbon bearing sandstones, which are separated by the saline-water-bearing sandstones of the Middle Donovan. The Ferry Lake Anhydrite, which overlies the three sections, serves as their caprock. </p><p> The present work is focused on an investigation of the feasibility of a CO₂-EOR project for the Citronelle Oil Field and the use of the Middle Donovan for long term CO₂ storage. A set of static calculations, based on estimation methods which were retrieved from publications in the field, was followed by computer simulations using MASTER 3.0, TOUGH2-ECO2N, and TOUGHREACT. Results using MASTER 3.0, for simulation of CO₂-EOR, indicated that nearly 50 million barrels of additional oil could be produced by tertiary recovery. Results using TOUGH2-ECO2N and TOUGHREACT, for the simulations of CO₂ storage, indicated that 159 million metric tons (175 short tons) of CO₂ could be stored in the Middle Donovan formation. An investigation into possible CO₂ leakage from the reservoirs indicated that the Ferry Lake Anhydrite serves as a very reliable long term storage seal.</p><p> The present work can serve as a template for preliminary assessment of tertiary oil recovery and CO₂ storage of similar oil reservoirs and saline-water formations.</p>

<p> Detecting leaks is always a priority in the oil and gas industry and plays a major concern to human safety. The time required to fix any leak has a direct relationship in determining the damages caused to the environment, industry, and most importantly, the number of lives lost caused by catastrophic pipe failures. Detecting leak size and location in pipelines with higher accuracy presents major challenges to operators. This research work presents an innovative solution to locate a leak location inside a pipeline with higher precision. The solution is based on generating a 3D model that establishes a relationship between leak noise and its associated location and size. In order to generate the 3D model, an experiment study was first conducted where a flow loop having a leak, integrated with an acoustic detection system, was built to collect data about the effect of leak size, flowrate, pipeline material, and length on the noise generated. Later, a numerical study used the experimental results to initiate a simulation that aimed at finding how the leak noise propagates from the leak location. Finally, the experimental and numerical results were combined into a 3D model equation that solves for the leak location based on the leak noise and size.</p><p>

<p> The quest for affordable energy continues to drive the need for new technology and push the limits of current practice. In the offshore arena of oil and gas exploration, massive drillships are used to penetrate reservoirs several thousand feet below the surface. The dynamic loading in the landing and casing string induced by an ocean environment is studied and a simplified model of heave in the string is developed in this thesis. An overview of the landing operations for intermediate casing strings and factors driving increasing lengths and weights of casing are presented. The available wave energy spectra for simulating the ocean wave environment and the ship&rsquo;s response to such an environment (particularly in heave) are discussed. A literature review of previous models of dynamic loading in tubulars aboard offshore vessels is presented. The development and validation of a simplified model based on two real-world case studies are also presented. Contrary to prior assumptions, for models with 10 to 50 lumped masses, an increase in the number of masses significantly decreases the dynamic loads compared to using fewer masses. A comparison of the model results to the case studies suggests that vessel heave from the ocean environment induced only a portion of the dynamic loads observed. The dynamic loads observed in the case studies are on the order of only 1% of static string weight. Operations in extreme waves are also simulated, and the maximum dynamic loads predicted are less than 5% of static string weight.</p><p>

<p> Gas hydrates pose economic and environmental risks to the oil and gas industry when plug formation occurs in pipelines. A novel approach using interfacial rheology was applied to understand cyclopentane clathrate hydrate formation in the presence of nonionic surfactant to achieve hydrate inhibition at low percent weight compared to thermodynamic inhibitors. The hydrate-inhibiting performance of low (&lt;CMC), medium (&ap;CMC), and high (>CMC) concentrations of Span 20, Span 80, Pluronic L31, and Tween 65 at 2 &deg;C on a manually nucleated 2 &mu;L droplet showed a morphological shift in crystallization from planar shell growth to conical growth for growth rates below 0.20 mm²/min. Monitoring the internal pressure of a droplet undergoing planar hydrate crystallization provided a strong correlation (up to <i>R</i> = &ndash;0.989) of decreasing interfacial tension to the shrinking area of the water-cyclopentane interface. Results from the high-concentration batch of surfactants indicated that while initial hydrate growth is largely suppressed, the final stage of droplet conversion becomes rapid. This effect was observed following droplet collapse from the combination of large conical growths and low interfacial tensions. The low-concentration batch of surfactants saw rapid growth rates that diminished once hydrate shell coverage was completed. The most effective surfactant was the high-concentration Tween 65 (0.15 g/100mL), which slowed hydrate growth to 0.068 mm²/min, nearly an order of magnitude slower than that found for pure water at 0:590 mm²/min. High molecular weight (1845 g/mol) and HLB (10.5) close to 10 contribute to a large energy of desorption at an interface and are believed to be the sources of Tween 65's hydrate-inhibiting properties. </p><p>

Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 248-254). Available also in a digital version from Dissertation Abstracts.

Thesis (Ph.D.)--University of Adelaide, Australian School of Petroleum (ASP), 2004. / "February 2003" PhD (by publication). Includes bibliographical references.

Thesis (M.S.)--King Fahd University of Petroleum and Minerals, 1989. / Title from document title page. Includes bibliographical references. Available in PDF format via the World Wide Web.

Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 216-221). Available also in a digital version from Dissertation Abstracts.

Thesis (Ph. D.). UM #74-17,941. / Title from document title page. Includes bibliographical references. Available in PDF format via the World Wide Web.