Engineering Commons^™

Experimental And Computational Investigation Of Flow Of Pebbles In A Pebble Bed Nuclear Reactor, Vaibhav B. Khane

Doctoral Dissertations

"The Pebble Bed Reactor (PBR) is a 4th generation nuclear reactor which is conceptually similar to moving bed reactors used in the chemical and petrochemical industries. In a PBR core, nuclear fuel in the form of pebbles moves slowly under the influence of gravity. Due to the dynamic nature of the core, a thorough understanding about slow and dense granular flow of pebbles is required from both a reactor safety and performance evaluation point of view.

In this dissertation, a new integrated experimental and computational study of granular flow in a PBR has been performed. Continuous pebble re-circulation experimental set-up, …

Degradable Nanocomposite Preformed Particle Gel For Chemical Enhanced Oil Recovery Applications, Paul Tongwa

Doctoral Dissertations

”This work presents two new materials that can be potentially used in conformance control to increase ultimate oil recovery from mature oilfields.

The first product is a degradable nanocomposite preformed particle gel for enhanced in-depth mobility control. Three different types of degradable nanocomposite preformed particle gels were synthesized. These three nanocomposite hydrogels were made using Laponite XLG, Calcium Montmorillonite, and Sodium Montmorillonite nanomaterials. It was observed that after degradation, Laponite XLG nanocomposite hydrogels had the highest post-degradation viscosity (4437 cp), followed by sodium nanocomposite hydrogels (129 cp), and lastly calcium nanocomposite hydrogels (75.5 cp). Thus, degradable Laponite XLG nanocomposite hydrogels …

Investigating And Modeling Tar-Mats In A Kuwaiti Carbonate Reservoir And Their Role In Understanding Oil Reserves And Recovery Economics, Abdullah Owidah Almansour

Doctoral Dissertations

"Tar-mat columns exist in many carbonate reservoirs in the Middle East. Historically, tar-mats have been thought to impede primary oil extraction, thus necessitating further improved oil recovery (IOR) technology applications. However, this research considers tar-mats as potential sources for unlocking extremely difficult crude oil, less than 5 ⁰API. The main objective of the study was to understand the qualitative physical and chemical properties of extremely viscous tar-mat oil and the quantitative potential of tar-mats to extract difficult oil.

The physical and chemical geneses of the tar-mat oil were analyzed utilizing several experimental geochemical techniques, including rock evaluation pyrolysis, liquid extracts …

Study And Pilot Test On A Novel Eor Method - Coupling Ppg Conformance Control And Surfactant Flooding, Farag Awadh Muhammed

Doctoral Dissertations

"The interest in enhanced oil recovery (EOR) methods has re-emerged in recent years; however, significant challenges remain for the widespread deployment of these methods. One major downside to the successful application of EOR technologies in mature reservoirs is conformance problems (e.g. heterogeneity). To mitigate these problems, a novel EOR method which couple preformed particle gel (PPGs) conformance treatment with traditional surfactant flooding in one process is introduced.

This dissertation provides a comprehensive study for the proposed method. A series of laboratory tests were carried out to understand the chemical interaction between PPGs and surfactants. A new method to evaluate PPGs …

Carbon Dioxide - Heavy Oil Systems: Thermodynamics, Transport And Interfacial Stability, Truynh Quoc My Duy Tran

Doctoral Dissertations

"Conventional oil recovery leaves behind around 67% of original oil in place for light oils and all of it for heavy oils. The carbon dioxide flooding process is the cheapest among the recovery methods for the next stage. The interest here lies in recovering heavy oil. When CO₂ dissolves in oil, it increases the volume of oil, squeezes it out of narrow capillaries and the viscosity of oil drops by up to an order of magnitude. Starting with the available data with and without CO₂ in heavy oil, the free volume theory is used to predict these physical …

Impact Of Slickwater Fracturing Fluid Compositions On The Petrophysical Properties Of Shale And Tightsand, Yongpeng Sun

Doctoral Dissertations

"A tight reservoir always requires hydraulic fracturing before production to increase production rate. The additives in hydraulic fluids are highly considerable for a successful stimulation. A friction reducer is often used to reduce the flowing friction in the wellbore during hydraulic fracturing. Extensive researches have been conducted to examine the extent it can reduce the fluid friction in tubings; however, no research has been reported on its behavior in a reservoir, which is related to the fracture extension. A breaker is also pumped into the formation to degrade the friction reducer. However, it is not clear that what is the …

Semantic Model And Updated Screening Criteria For Polymer Flooding, Laila Dao Saleh

Doctoral Dissertations

"Enhanced oil recovery (EOR) processes produce oil that conventional methods leave behind, where interfacial forces, heavy oil viscosity, and reservoir heterogeneity make it difficult to produce. Many EOR methods are available but usually cannot be used at the same time for a candidate reservoir. Therefore, it is important to select the most appropriate EOR process from among the possible techniques. EOR screening criteria have been created using EOR datasets and serve as the first step to compare the suitability of each technique for a specific reservoir. Most of these datasets are based on field data collected from EOR surveys published …

Preformed Particle Gel Transport Through Fractures, Hao Zhang

Doctoral Dissertations

"Polymer gel treatment is one of the most cost-effective methods to control water production in mature oil fields. The main objective of gel treatments is to reduce water or gas flow through high-permeability channels or fractures without damaging productive zones. Preformed particle gels (PPGs) have been applied for conformance control because they can overcome some potential drawbacks inherent in an in-situ gelation system.

In this study, lab experiments were performed to quantify PPG propagation through fractures and fracture-like channels by using screen models and open fracture models. The main findings in these experiments can guide the selection of best particle …