Mathematical Modelling of Wax Deposition in Crude Oil Pipeline Systems

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractDeposition of wax on the wall of the crude oil pipelines is regarded as a problem since the pipeline diameter is reduced. Therefore more power is required to force the same amount of crude oil through the system. In this study, a mathematical model is developed for estimation of wax deposition in crude oil pipeline systems. A computer program was developed to simulate wax deposition phenomena. Each component is characterized by weight fraction, heat of fusion and melting point temperature. Temperature profile along the pipeline, solid-liquid equilibrium constant, wax mole fraction and wax thickness along the pipeline were calculated. This computer program was applied to Kirkuk -Ceyhan crude oil pipeline system. It was observed that wax thickness, after a year, is approximately 0.34 mm and temperature declined from 303 K to around 295 K. The wax mole fraction after a year is approximately 0.2225. The solid-liquid equilibrium constant for the first component was around 0.29 and 355 for the second component after a year.

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