Numerical Model for Wax Deposition in Oil Wells

Modeling of Deposition from “Waxy” Mixtures in a Pipeline under Laminar Flow Conditions via Moving Boundary Formulation

“…The contribution of Brownian diffusion was considered relatively small as compared to the other mechanisms. Models based on the molecular diffusion approach have been proposed for predicting wax deposition. − Predictions based on the molecular diffusion approach have been reported for different thermodynamic models for the solid−liquid equilibrium. − …”

“…[5][6][7][8][9][10][11] Predictions based on the molecular diffusion approach have been reported for different thermodynamic models for the solidliquid equilibrium. [12][13][14] The important role of heat transfer in solids deposition from waxy crude oils has been identified in a number of studies. [15][16][17][18][19][20][21] While earlier studies reported increased deposition with an increase in the overall temperature difference, recent studies have shown that the temperature difference across the deposit is more significant.…”

Modeling of Deposit Formation from “Waxy” Mixtures via Moving Boundary Formulation: Radial Heat Transfer under Static and Laminar Flow Conditions

“…Many of the available models for solids deposition from waxy oils are based on molecular diffusion as the dominant mechanism. [5][6][7][8][9][10][11][12][13] This approach is based on the premise that the flow of (hot) crude oils in a pipeline with the wall temperature below the WAT provides a radial temperature gradient, which creates a radial concentration gradient for molecular diffusion. A few of the studies using the molecular diffusion approach differ in the thermodynamic treatment of solid-liquid phase equilibria.…”

“…A few of the studies using the molecular diffusion approach differ in the thermodynamic treatment of solid-liquid phase equilibria. [9][10]12 Modeling studies have also dealt with deposit removal by shear, 5,7,14 deposit aging, 7,13,15 and solids deposition under multiphase flow conditions. 16 The flow rate (or the rate of shear) was shown to be an important factor for solids deposition.…”

“…Many of the available models for solids deposition from waxy oils are based on molecular diffusion as the dominant mechanism. − This approach is based on the premise that the flow of (hot) crude oils in a pipeline with the wall temperature below the WAT provides a radial temperature gradient, which creates a radial concentration gradient for molecular diffusion. A few of the studies using the molecular diffusion approach differ in the thermodynamic treatment of solid−liquid phase equilibria. −, Modeling studies have also dealt with deposit removal by shear, ,, deposit aging, ,, and solids deposition under multiphase flow conditions , The deposit mass has been reported to decrease with increasing flow rate regardless of the flow being laminar or turbulent. ,, Also, the deposit composition and “hardness” have been observed to vary with time through deposit aging. ,,,− …”