Miscible displacement tests

The purpose of the miscible displacement tests was, primarily, to evaluate the effect of the surfactant on the interaction between the high pressure CO2 and the crude oil. The miscible displacement process is so efficient in linear laboratory tests that any improvement would be minor. However, any interference with the mechanism of miscibility should be detrimental to the recovery efficiency and easily observed. 

Table III - Surfactants used in Miscible Displacement Tests...

Results of the Miscible Displacement Tests. The results of the tests are shown in Figures 9-12. Referring first to Figure 9, the CO2 flood of a waterflooded light oil reservoir, it can be seen that the waterflood, represented by the data prior to CO2 injection, recovered 0.5 PV of oil. This amount represented 76% of the oil initially in place and produced a residual oil saturation... 

In an effort to describe effluent results obtained from the different soil layers, we utilized various versions of the multireaction model described above. In principle, we based our efforts on the assumption of the miscible displacement approach that describes retention reactions of solutes during transport in porous media (Selim, 1992). Several simplifying assumptions were necessary in order to describe the S04 experimental data based on these models. Briefly, we tested the capability of the convection-dispersion (CD) equation to describe the mobility of applied sulfates in individual soil layers where steady-state conditions were assumed. 

Tertiary oil was increased up to 41% over conventional CO2 recovery by means of mobility control where a carefully selected surfactant structure was used to form an in situ foam. Linear flow oil displacement tests were performed for both miscible and immiscible floods. Mobility control was achieved without detracting from the C02-oil interaction that enhances recovery. Surfactant selection is critical in maximizing performance. Several tests were combined for surfactant screening, included were foam tests, dynamic flow tests through a porous bed pack and oil displacement tests. Ethoxylated aliphatic alcohols, their sulfate derivatives and ethylene oxide - propylene oxide copolymers were the best performers in oil reservoir brines. One sulfonate surfactant also proved to be effective especially in low salinity injection fluid. 

The displacement tests show that a signiflcant increase in tertiary oil production can be achieved when one of the better additives is utilized in 1-dimensional laboratory immiscible carbon dioxide floods. In the miscible displacement case no adverse effect on the miscibility process was found. In... 

The comparability of the two methods was further tested by attempting to use kinetic-parameter values determined by gas purge to predict breakthrough curves (BTC) obtained from the same soil/solute pairs. A BTC obtained from miscible displacement of PCE through the Eustis soil column is presented in Fig. 11-5. The values for ki and F (fraction of sorbent for which sorption is instantaneous) determined from the Eustis/PCE gas-purge experiment were used to calculate values for /3 (fraction of instantaneous retardation) and w (ratio of hydrodynamic residence time to reaction time). The simulation produced by a first-order bicontinuum model (Brusseau and Rao, 1989a) with these independently determined kinetic parameters is shown in Fig. 11-5. The model simulation compares extremely well with the experimental BTC. Such predictions for organic chemicals, where values for... 

Micellar flooding is a promising tertiary oil-recovery method, perhaps the only method that has been shown to be successful in the field for depleted light oil reservoirs. As a tertiary recovery method, the micellar flooding process has desirable features of several chemical methods (e.g., miscible-type displacement) and is less susceptible to some of the drawbacks of chemical methods, such as adsorption. It has been shown that a suitable preflush can considerably curtail the surfactant loss to the rock matrix. In addition, the use of multiple micellar solutions, selected on the basis of phase behavior, can increase oil recovery with respect to the amount of surfactant, in comparison with a single solution. Laboratory tests showed that oil recovery-to-slug volume ratios as high as 15 can be achieved [439]. 

The Pt-Au systemhasbeen a valuable system to test DENs potential forpreparing NP systems of interest to the heterogeneous catalysis community. It is synthetically challenging, characterized by a wide bulk miscibility gap (18 to 98% Pt), and bimetallic NPs within this gap are unavailable by traditional routes. Nuzzo and coworkers have shown that bulk phase diagrams may not necessarily hold true for NPs " and results with the Pt-Au system support this conclusion provided appropriate syntheses are available. Utilizing Cu displacement syntheses, these substantial... 

This developed miscibility process results in a miscible fluid, that is capable of displacing all the oil which it contacts in the reservoir... The efficiency of this displacement is controlled by the mobility (ratio of relative permeability to viscosity) of each fluid. If the displacing fluid (i.e. carbon dioxide) is more mobile than that being displaced (i.e. crude oil) then the displacement will be relatively inefficient. Some of the residual oil saturation will never come into contact with carbon dioxide. Both laboratory and field tests have indicated, that even under favourable condition, injection of 0.15-0.6 10 m of carbon dioxide is required for recovery of an additional barrel (0.16 m ) of oil". Here our goal is to obtain a mass ratio of CO2 to incremental oil of 1 to 4, on the basis of the Bonder s data. 

Nitroparaffins are not explosives as determined by tests approved by the U.S. Department of Transportation (DOT) for shipping classifications. However, nitromethane when sensitized by small amounts of amines can be detonated by a Number 8 blasting cap. Nitromethane is used as a fuel component in ammonium nitrate explosives. Nitroparaffins are used in diesel fuel to increase power output of engines. Nitropropane is completely miscible in diesel fuel, nitroethane solubility is 18 wt%, and nitromethane is only a 2 wt%. Nitromethane is used as a fuel in racing cars and in model engines. A blend of nitromethane and methanol is said to produce increased power output over regular hydrocarbon fuels. 1-Nitropropane is used as a grinding solvent for the production of aluminum powder because of its ability to displace surface moisture on the aluminum and the solvent aids in the dispersion of the aluminum powder. Nitromethane is used as a metal stabilizer for... 

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