In this paper, the
Eulerian approach was applied to model asphaltene
deposition process in turbulent production pipeline. In addition to
common mechanisms such as drag, lift, gravity, and molecular diffusion,
the most effective deposition mechanisms such as eddy diffusion, turbophoresis,
and thermophoresis were considered over a wide range of asphaltene
particle sizes (i.e., 1 nm–100 μm). Modeling results
showed that, for small submicrometer-sized particles (<1 μm),
the diffusion mechanism (including molecular and eddy diffusions)
plays a significant role; however, for large particles, because of
the inertia effect, eddy diffusion and turbophoresis were the dominant
mechanisms. It was also found that temperature gradient has no significant
effect on asphaltene particle deposition. In the modeling, the effect
of oil velocity, surface roughness, particle size, and surface temperature
on asphaltene deposition was also investigated. The results showed
that asphaltene deposition velocity was increased with increasing
oil flow velocity, while increasing the deposition velocity by increasing
the surface roughness occurred only for particles <20 μm
in size. Finally, by using the asphaltene particle size distribution
based on the log-normal distribution function, the asphaltene deposition
flux was calculated and validated with available experimental data.