The advent of smart well technology, which is the use of down hole sensors to adjust well controls (i.e. injection rate, bottomhole pressure, etc.), has allowed the possibility to control a field in all stages of the production. This possibility holds great promise in better managing enhanced oil recovery (EOR) processes, especially in terms of applying optimization techniques. However, some procedures for optimizing EOR processes are not based on the physics of the process, which may lead to erroneous results. In addition, optimization of EOR processes can be difficult, and limited, if there is no access to the simulator code for computation of the adjoints used for optimization. This research describes the development of a general procedure for designing an initial starting point for a surfactant flood optimization. The method does not rely on a simulator's adjoint computation or on external computing of adjoints for optimization. The reservoir simulator used for this research was Schlumberger's Eclipse 100, and optimization was accomplished through use of a program written in Matlab. Utility of the approach is demonstrated by using it to optimize the process net present value (NPV) of a 5-spot surfactant flood (320-acres) and incorporating the optimization solution into a probabilistic geological and economic setting. This thesis includes a general procedure for optimizing a surfactant flood and provides groundwork for optimizing other EOR techniques. This research is useful because it takes the optimal solution and calculates a probability of success for possible NPVs. This is very important when accessing risk in a business scenario, because projects that have unknown probability of success are most likely to be abandoned as uneconomic. This thesis also illustrates possible NPVs if the optimal solution was used.

The purpose of matrix stimulation in carbonate reservoirs is to bypass damaged zones and increase the effective wellbore area. This can be achieved by creating highly conductive flow channels known as wormholes. A further injection of acid will follow a wormhole path where the permeability has increased significantly, leaving substantial intervals untreated. Diverting materials such as surfactant-based acids plays an important role in mitigating this problem. In this study and for the first time, 20-inch long cores were used to conduct the acidizing experiments in two configurations, single coreflood and parallel coreflood. The major findings from performing single coreflood experiments can be summarized as follows: The acid injection rate was found to be a critical parameter in maximizing the efficiency of using surfactant-based acids as a diverting chemical, in addition to creating wormholes. The maximum apparent viscosity, which developed during viscoelastic surfactant acid injection, occurred over a narrow range of acid injection rates. Higher injection rates were not effective in enhancing the acidizing process, and the use of diverting material produced results similar to those of regular acids. The amount of calcium measured in the effluent samples suggests that, if the acid was injected below the optimum rate, it would allow the acid filtrate to extend further ahead of the wormhole; at some point, it would trigger the surfactant and form micelles. When the acid injection rate was lowered further to a value of 1.5 cm3/min, the fluid front developed in more progressive fashion and the calcium concentration was more significant, continuing to increase until wormhole breakthrough On the other hand, the parallel coreflood tests show several periods that can be identified from the shape of the flow rate distribution entering each core. The acid injection rate was confirmed as influencing the efficiency of the surfactant to divert acid. Acid diversion was noted to be most efficient at low rates (3 cm3/min). No significant diversion was noted at high initial permeability ratios, at least for the given core length. The use of surfactant-based acid was also found to be constrained by the scale of the initial permeability ratio. For permeability ratios greater than about 10, diversion was insufficient.

High-resolution and low-cost fabrication techniques are essential for nanotechnology to overcome the commercialization barrier to benefit our society. Since its inception nanoimprint has become the ideal technology to fabricate dense sub-micron structures over large areas with low cost, which are important to many applications such as high-density storage disks and diffractive optical devices. The decade-long development in nanoimprint equipment has reached a point where large-scale manufacturing of high-density nanostructures are possible. However, there are a few remaining issues that need to be studied before the advent of commercial application of nanoimprint. In this work we look at a pressing issue, long-term stability of the mold surfactant coating. It is important to understand the details of the surfactant wear during nanoimprint in order to limit defect density to a tolerable threshold in a high-volume manufacturing process. To study this we went through a nanoimprinting procedure and measured chemical and physical alterations in the coating. The surfactant wear information also helps to optimize the time interval for surfactant recoating to keep the fabrication throughput as high as possible. In this paper we characterize the stability of two commonly used surfactants as well as prescribe a new technique for mold anti-adhesion. Through this work we see that FDTS and OTS undergo significant degradation in air and gradual degradation by chain scission is observed during the nanoimprint procedure. It is also noted that an embedded anti-adhesion layer is effective for mold releasing.

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Polymer-free viscoelastic surfactant-based (VES) fluid systems have been used to eliminate polymer-based damage and to efficiently transport proppants into the fracture. Current models and correlations neglect the important influence of fracture walls and fluid elasticity on proppant settling. This report presents an experimental study that investigates the impact of fluid elasticity and fracture width on proppant settling in VES fluid systems. Proppant settling experiments are performed in shear-thinning VES fluids. Experimental data is presented to show that fluid elasticity plays an important role in controlling the settling rate of the proppants. It is shown that elastic effects can increase as well as reduce the settling velocities depending upon the rheological properties of the fluid and properties of the proppants. Data is presented to show that the settling velocity reduces significantly as the proppant size becomes comparable to the fracture width. The reduction in settling velocity due to the presence of the fracture walls depends on the rheological properties of the fluid, ratio of particle diameter to fracture width as well as the diameter of the particle. / text

The aim of the project was to modify polydimethylsiloxane (PDMS) surfaces in order to minimize adsorption of proteins. PDMS is used in micro-fluidic devices that control the delivery of samples to a sensor chip in Biacore instrumentation. These instruments are used to characterize interactions between biomolecules with a detection principle based on surface plasmon resonance (SPR). To minimize adsorption of proteins poly-ethylene-oxide (PEO) based surfactants, were added to the buffer. The added PEO surfactants were P20, Pluronic F-127 and Brij 35. Interaction of these surfactants with the sensor chip in Biacore instruments was also examined. Creating a more hydrophilic surface layer on PDMS by oxidation was also examined. When surfactants were continuously added to protein samples, as in dynamically coating of PDMS surfaces, Brij 35 resulted in the strongest reduction in protein adsorption. Brij 35 was also the surfactant that was easiest to remove from both PDMS and the sensor surfaces. Pluronic bound strongest to surfaces, and is most suitable when only adding surfactant to the buffer in a pre-coating step. All surfactants did reduce protein adsorption considerably (99% or more) and addition is necessary when working with protein solutions and hydrophobic surfaces as PDMS. Another alternative is oxidation of PDMS surface, which is an easy procedure that decreased the protein adsorption to about 10% compared to adsorption to untreated surface.

Drag reduction is a well-observed phenomenon, it was first observed by the British chemist Toms in 1946, yet its mechanism is still unknown to this day. Polymer Drag reduction has found application in reducing pumping costs for oil pipelines (its use in the Trans Alaska Pipeline has resulted in an increase from 1.44 million bbl./day to 2.1356 million bbl./day), increasing the flow rate in firefighting equipment , and in supporting irrigation and drainage systems. Surfactant drag reducers are used industrially in district heating and cooling systems. Though the fields of Surfactant Drag Reduction and Polymer Drag Reduction are each independently well-developed the effect of their interaction on drag reduction is a less explored phenomenon. Through a well chosen pairing of surfactant and polymer, drag reduction can be maximized while minimizing surfactant and polymer concentrations cutting down on cost and environmental impact. The focus of this work was to determine if there was any positive interaction between the polymers Polyethylene Oxide (PEO) and Anionic PolyAcrylAmide (PAM) and the surfactant Amphosol CG (Cocamidopropyl Betaine) as well as any interaction between the polymers themselves. Both polymers are popular drag reducers while Amphosol is a practically nontoxic (LD50=5g/kg) zwitterionic surfactant and is readily biodegradable. In order to determine if any interaction was present and at what concentration was this most notable 4 techniques were used: Surface tension, Conductivity, Relative Viscosity and Shear Viscosity measurement. From this analysis the polymer Saturation point (PSP), Critical aggregation concentration (CAC) and Critical micelle concentration (CMC) were found as well as the concentrations that optimized the viscosity for the pilot plant runs. The bench scale results were used to pick the optimum concentrations for the polymer surfactant solutions. Pressure readings and flowrate measurements were used to plot the Fanning Friction Factor against the Generalized Reynolds Number for the surfactant polymer mixtures and compared to their pure polymer and surfactant counterparts. The Blasius line was found to hold for water measurements taken and is the base to determine percentage drag reduction. The effect of the presence of amphosol on degradation and overall drag reduction were noted. Other factors considered were pipe diameter and the effect of ionic impurities in the solvent.

Advances in analytical chemistry have resulted in a growing body of literature showing measurable concentrations of pharmaceuticals in both drinking and wastewater. Removal of such chemicals is typically inefficient and often poorly characterized. To characterize one such method of removal (micellar enhanced ultrafiltration, (MEUF)), interactions of a cetyl trimethylammonium bromide (CTABr) surfactant and sulfonamide antibiotics were examined by NMR and semi-equilibrium dialysis (SED). The locus and orientation of binding in a micelle was established for seven sulfonamides by 1H NMR, and it was found that hydrophilic sulfonamides showed weak coordination with the micelle, whereas hydrophobic sulfonamides penetrated into the micellar interior with coordination of the SO2NH group to the charged surface layer. Binding constants were determined by 1H NMR and showed apparent order of magnitude differences between nuclei. Several compounds were unable to be characterized in this manner due to low change in chemical shift with addition of CTABr. SED was performed as an alternative method to determine binding constants. Values determined in this manner were higher than those determined by 1H NMR. Binding constants were converted into changes in Gibbs free energy and used to evaluate and, where necessary, modify the orientation and locus proposed by 1H NMR. Attempts are made to correlate binding constants with octanol-water partition coefficients to determine if a free energy relationship can be derived. Characterization of these systems may allow for a predictive methodology to determine the MEUF removal efficiencies of new sulfonamide and surfactant combinations. It is also hoped that this work may be generalized to predict MEUF efficiency for a wide range of contaminants that might be found in wastewater. / Thesis (Master, Chemistry) -- Queen's University, 2011-01-31 09:46:28.248

The overall objective of this PhD thesis research is to characterize, understand and ultimately control phase-separated structures in mixed films consisting of a perfluorinated fatty acid and a photopolymerizable surfactant. In these systems, film morphology, mechanical properties and spectroscopic properties are inter-related and this thesis explores these relationships. In this context the interaction between perfluorotetradecanoic acid (C13F27COOH, referred to as PF in this dissertation), and 10,12-pentacosadynoic acid (CH3(CH2)11−C≡C−C≡C−(CH2)8COOH, referred to as PCDA in this dissertation) has been studied in monolayers using a combination of surface and spectroscopic characterization techniques. To investigate the inter-relationship of the properties described above, film behavior under a variety of conditions, including behavior at different interfaces (solid-liquid, air-liquid), different film compositions and under different conditions of photoillumination and mechanical stress were explored. Thermodynamic and morphological studies of mixed monolayer surfactant films of PF and the photo-polymerizable diacetylene molecule, PCDA, were carried out. The films were prepared at the air-water interface and transferred onto solid supports such as a glass slides via Langmuir-Blodgett (LB) deposition technique. The presence of the perfluoroacid helped to stabilize the diacetylene surfactant monolayer in comparison with the diacetylene alone, allowing film transfer onto solid substrates without needing to add cations to the sub-phase or photo-polymerize the components prior to deposition. Addition of the perfluorocarbon to PCDA resulted in films with the photopolymer strands oriented perpendicular to the direction of the film compression in a Langmuir trough. This is in contrast with film structures formed from pure PCDA. Formation of these features could be explained by a two-step process that happened sequentially: first, the compression of monolayer with trough barriers while trying to maintain the surface pressure constant induces stress on the film surface; second, additional film buckling which was enhanced by the strong cohesion between PF and PCDA. Film compression data, supported by in situ fluorescence spectrophotometry, Brewster angle microscope imaging and atomic force microscope images of deposited films, supported this mechanism. Factors that controlled the orientation of the photopolymer fibers were also investigated. Fibers were found to consist of multiple strands, with each strand having a different orientation. Our investigation also revealed there was a preferred orientation for fibers in the film as a whole. The angle of approximately 60o to the direction of film compression during deposition from a Langmuir trough has been calculated with the help of dual-view, polarized fluorescence microscopy. This orientation was attributed to the mechanical stress exerted by the trough compression barriers coupled with rotation of the polymer fibers during film draining. The combination of Atomic Force Microscope (AFM) and fluorescence microscopy (FM) provided a thorough and comprehensive mapping of fundamental properties of mixed monolayer system, and enabled a quantitative determination of the degree of selectivity of the polymerization process.

To date, an estimated 70% of energy consumed comes from fossil fuels, such as coal, oil and natural gas. The major source of sulfur dioxide (SO2) emissions comes from combustion of these fossil fuels. Sulfur dioxide is a significant pollutant, because it and its higher oxidation product (SO3) react with moisture in the atmosphere to produce sulfuric acid. This results in acid rain, which comes back to earth and affects people, animals, and vegetation. Therefore, the governments of Canada, US and European countries are issuing stricter and stricter regulation to control SO2 emissions. In conventional SO2 removal processes, lime or limestone scrubbers are used, but they require large amounts of water and enough landfill sites to deal with the solid wastes. Previous attempts were made in our laboratory to recover SO2 adsorbed on activated carbon to produce sulfuric acid using non-aqueous solvents. Unfortunately, in this adsorption/distillation process, the SO2 recovery was low, as was the quality of sulfuric acid, that could not be marketable. The topic of this thesis was then conceived as an attempt to first recover SO2 via SO3 formation using supercritical carbon dioxide instead of water or non-aqueous flushing agents (desorption step) and then to use the recovered SO3 to produce linear alkylbenzene sulfonates (LAS), the main component of detergent. In the adsorption and oxidation experiments of this project, charcoal activated carbon (AC) was used to adsorb SO2 and to catalyze SO2 oxidation. The process started with a simulated flue gas, 3500 ppm SO2, 5% O2, balanced with N2. When the simulated flue gas passed through the activated carbon bed reactor, more than 95% of SO2 was oxidized to SO3. In the desorption process, SO3 contacted with the AC bed was removed using supercritical carbon dioxide (SCCO2) and 95% sulfur removal was achieved at appropriate operating conditions, for example, for a carbon bed preheated at 250??C for 6 h, and flushed by recycled SCCO2. The LAS production experiments consisted in reacting liquid linear alkylbenzene (LAB) with the recovered SO3 in an absorption column. Ceramic filters and glass beads were used in the absorption columns to break up the gas bubbles and increase the contact time between the gas and the liquid absorbent. When staged pressure columns were used and when LAB was heated to 40??C, nearly 95% of SO3 reacted with LAB to produce LAS.