Waxy crude oil transportation in Gulf-sirt offshore field.

Abstract

Crude oil transportation in the pipe lines connecting platforms at projected offshore Gulf-Sirt project is assumed in this paper. The precipitation of the solid phase of wax in the pipe wall creates pressure abnormalities and causing an artificial blockages leading to a reduction or interruption in the production. Wax can precipitate as a solid phase on the pipe wall when its temperature drops below the appearance temperature
(WAT).

This work is aimed to study the wax deposition process on the internal surface of oil production pipelines and the influence of parameters such as flow rate, pipe wall temperature, Insulated Pipeline, Effect of Crude-Oil Composition (or WAT), Effect of Crude-Oil and Seawater Temperatures on the deposit thickness. The analysis was conducted assuming pseudo steady conditions on the fluid phase, the solution was implemented numerically using the MATLAB PROGRAMMING. The results showed that increased flow rates reduce the maximum deposit thickness, insulation preventing further solids deposition, The higher WAT gave a larger deposit thickness, reduction in the amount of deposited solids with an increase in either the crude-oil temperature or the seawater temperature, as it spreads on a longer distance in the pipe when considering a constant wall temperature or the axial thermal gradient with a positive slope, and the opposite effect is observed when considering the axial thermal gradient with a negative slope.