الملخص الإنجليزي
The effectiveness of using waste bio materials as viscosity reducing agents was investigated on light and heavy crude oils of Oman. The selected materials are fiber of palm tree, date palm kernel and walnut shell. The utilization of waste bio materials is not only considered as a cost effective, but, environmentally friendly and has less effect on crude oil processing as compared to that of chemical additives. In this study, special piping structure was constructed to measure flowabilty time of crude oil. It was observed that use of bio materials reduced oil flowability time by range of 42–50% using particle size 75 µm and by 66% using particle size 150 µm. Moreover, the effect of different additives and various concentrations of bio materials on oil rheological properties, for instance viscosity and yield stress, were also studied. Results showed that the light crude oil exhibits a non-Newtonian viscoplastic behavior following (Bingham plastic model) whereas the heavy crude oil exhibits a non-Newtonian pseudoplastic behavior (shear thinning model). The use of bio materials reduced the limiting viscosities of the light crude oils by 62% using particle size 75 µm and 75% using particle size 150 µm. However, limiting viscosity of heavy crude oil was reduced by 15%. In addition, it was observed that using bio materials lowered yield shear; light crude reduced by average 32% while heavy crude oil reduced by 10%.
