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In the Prausnitz tradition, molecular and macroscopic evidence of hydrate formation and kinetic inhibition is presented. On the microscopic level, the first Raman spectra are presented for the formation of both uninhibited and inhibited methane hydrates with time. This method has the potential to provide a microscopic-based kinetics model. Three macroscopic aspects of natural gas hydrate kinetic inhibition are also reported:  (1) The effect of hydrate dissociation residual structures was measured, which has application in decreasing the time required for subsequent formation. (2) The performance of a kinetic inhibitor (poly(N-vinylcaprolactam) or PVCap) was measured and correlated as a function of PVCap molecular weight and concentrations of PVCap, methanol, and salt in the aqueous phase. (3) Long-duration test results indicated that the use of PVCap can prevent pipeline blockage for a time exceeding the aqueous phase residence time in some gas pipelines.

The first phase equilibrium data are presented for Structure H hydrates. The data represent the initial formation of these hydrates from methane, with adamantane— a previously determined Structure H former. Temperature and pressure conditions are consistent with hydrocarbon production/transportation/processing facilities. Structure H hydrates are shown to contain molecules indigenous to petroleum. which may not be present in natural gas.

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An overview is given of the development and field testing of a non-thermal, viscous oil recovery technology that injects into a reservoir oil-external solids-stabilized emulsions (SSE) as a displacement fluid. The emulsion is generated on site using produced crude oil and water. Small amounts of added mineral fines are used to enhance the performance of naturally present surface-active components in the oil. Gas is dissolved into the oil to adjust the viscosity of the injected emulsion to be similar to that of the in situ oil. SSE fluid displaces viscous oil in a miscible-like manner with favorable mobility, which leads to to improved displacement and recovery. SSE is generally applicable to reservoirs with in situ oil viscosities of up to approximately 3000 cP and permeabilities on the order of one Darcy or more.A series of laboratory tests were conducted to confirm the effectiveness of solids-stabilized emulsions as displacing agents. Specialized coreflood were used to measure emulsion stability, confirm process understanding, and to determine displacement efficiencies. After lab testing and reservoir modeling, a field pilot of the SSE process was designed, constructed, and operated. The field piloting confirmed the ability to generate and sustain injection of a solids-stabilized emulsion in the field and to propagate stabilized emulsions in the reservoir. IntroductionRecovery is challenging for viscous-but-mobile oils that have in situ oil viscosities of tens to several thousands of centipoise. Cold-flow primary recovery and waterflooding are often proven, cost-effective ways to recover viscous oils. Unfortunately, these recovery methods may leave the majority, and sometimes the vast majority, of the viscous oil in the reservoir. Without aquifer support, primary recovery of viscous oils typically suffers from limited drive energy. Waterfloods provide drive energy, but the unfavorable mobility ratio between the injected water and in situ oil usually leads to inefficient displacement and low recoveries. Polymer flooding, which adds a water-soluble polymer to injected water to increase its viscosity, can sometimes be used to improve viscous oil displacement and recovery, but economic application is typically limited to reservoirs of moderately low salinity and temperature. Steam-based methods can be used for improved recovery of viscous oils, but these methods may be costly to implement, especially in thin reservoirs, and may be impractical in deep reservoirs.