Crude oil viscosity

NaCl aqueous solution. About six pore volumes of the same solution was injected to stabilize the clay as well as to determine the absolute permeability and porosity (average permeability = 380 millidarcy, average porosity = 0.19). The porous medium was then flooded with Salem crude oil (viscosity at room temperature = 6 cp) to irreducible water content. Waterflood (1% NaCl) was carried out to waterbreak-through. The surfactant solution (3.16 x 10 mol/il,... 

If experimental data for the crude oil viscosity are not available an estimate can be made in the following manner. If the liquid is below the saturation pressure the viscosity is estimated with the aid of Figures 76 and 77. Figure 76 shows the viscosities at one atmosphere pressure for various API stock tank oils at various reservoir temperatures. Since crude oils vary widely in composition the prediction of viscosities by this simple correlation shows an average deviation of about 25% when compared to experimental values. After... 

Economic pipeline transport of viscous crudes as concentrated oil-inwater emulsions has been demonstrated in at least two commercial pipelines. The present study was undertaken to learn more about the rheological characteristics of concentrated emulsions and the effect of such variables as emulsion formulation and preparation techniques, aging,and crude oil viscosity on emulsion properties. 

This paper reports results on one phase of a program of study of concentrated oil-in-water emulsions, namely the effect of several composition variables on the apparent viscosity of concentrated (60 volume percent) crude oil-in-water emulsions. In particular, the effects of NaOH content, NaCl content, emulsion preparation technique, crude oil viscosity and aging of emulsion were studied. 

Historically, physical properties such as boiling point, density (gravity), odor, and viscosity have been used to describe oils. Petroleum may be called light or heavy in reference to the amount of low-boiling constituents and the relative density (specific gravity). Likewise, odor is used to distinguish between sweet (low sulfur) and sour (high sulfur) crude oil. Viscosity indicates the ease of (or more correctly the resistance to) flow. 

Mechanisms of oil recovery due to this process include (1) reduction of flow resistance near the well bore by reducing the crude oil viscosity and (2) enhancement of the solution gas drive mechanism by decreasing the gas solubility in an oil as temperature increases. 

The polymer solution was prepared by diluting the 30,000-ppm oil-external polyacrylamide stock solution to a concentration which yielded a viscosity in the range of 0.001 to 0.004-Pa.s higher than the crude oil viscosity. 

During the preparation of alkaline/polymer blend solution (30HPA/NaOH) samples it was observed that the viscosity of the sample was decreasing continuously in time. Therefore, the addition of more polymer into the caustic solvent became a necessity in order to set the viscosity of the 30HPA/NaOH sample to a value slightly higher than the crude oil viscosity. While adding more polymer, a time of 10-hours had to elapse for the viscosity reduction to level off and become relatively constant. 

The high viscosity of heavy oils has been ascribed to high concentrations of asphaltenes [42, 43]. That high concentrations of asphaltenes and resins can lead to high crude oil viscosities is exemplified by the data presented in Figure 10.4 for a series of degassed oils at ambient temperature. It has also been argued that asphaltenes represent nucleation sites for gas bubble formation [39] and can adsorb... 

B.M Yaghi and A. A1 Bemani, (2002) Heavy Crude Oil Viscosity Reduction for Pipeline... 

Coreflood temperature 68°F, crude oil viscosity 7.3 cP, produced water containing 3.3% total dissolved solids (of which 2700 ppm Ca + + Mg +) surfactant concentration range in ASP slug 0.1-0.2 wt.% polyacrylamide concentration in ASP and polymer slugs-550 mg/L injection sequence - 3 pore volumes (Vp) produced water, 0.3 Vp ASP slug, 0.3 Vp polymer slug, 3 Vp injection water. 

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