Statoil polymer

Figure 22 shows the effect of polymer concentration on the flow curves of Statoil polymer in deionized water. At polymer concentrations 2,000 ppm, the apparent viscosity was constant at low shear rates (Newtonian behavior) and decreased at higher shear rates. The Carreau model. Equation 8, predicts the experimental data for this polymer concentration range fairly well. At polymer concentrations > 2,000 ppm, the flow curves showed a shear thinning behavior only. The power-law model. Equation 9, predicts the data fairly well at shear rates > 1 s. ... 

Figure 22. Flow curves of Statoil polymer in deionized water.

Figure 23 shows that the screen factor monotonically increased with polymer concentration for both xanthan materials. However, the Statoil polymer showed higher screen factors, especially at higher polymer concentrations. At high shear rates, shear viscosities obtained by extrapolating the data shown in Figure 22 are slightly lower than those obtained from the screen viscometer shown in Figure 23. This trend indicates that the elastic properties of xanthan gum are not as significant as those of HPAM.

Figure 25. Effect of sodium chloride concentration on the flow curves of Statoil polymer solutions having 2,000 ppm polymer.

Figure 27 is similar to Figure 26, but for the Statoil polymer. The effect of sodium chloride on the polymer flow curves was similar to that observed at lower polymer concentrations. There was no increase in the apparent viscosity as a result of adding sodium chloride, other than that expected from the solvent viscosity at sodium chloride concentrations of 3 and 5 wt%. 

Figure 34 displays the effect of Triton X-100 on the flow curves of polymer solutions having 2,000 ppm Statoil polymer. The influence of up to 10 wt% Triton X-100 on the flow curves of Statoil polymer was not significant. These results suggest that Triton X-100 (a nonionic species) does not interact physically or chemically with the polymer chain in deionized water. 

Figure 35 is similar to Figure 34, but the flow curves were measured as a function of Neodol 25-3S concentration. Unlike the trend observed with Triton X-100, Figure 35 shows that the apparent viscosity of Statoil polymer dropped as the surfactant concentration was increased to 1 wt%, then monotonically increased with further increase in the surfactant concentration. This behavior is very similar to that observed with simple salts. 

At low polymer concentrations, simple salts caused a slight reduction in the viscosity of Statoil polymer (a medium pyruvate content xanthan), and a more noticeable change in the flow curves of Flocon 4800 (a high pyruvate content xanthan). However, at higher polymer concentration, the addition of salts increased the apparent viscosity of the high pyruvate content xanthan. 

This work has been supported by Borealis, Dyno, Statoil, Hydro, Reichhold, and the Research Council of Norway, and is a part of the research project Reactor Technology in Petrochemistry and Polymer Industry (REPP). 

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