Physico-chemical Study of Dar Crude Oil Blend

Abstract

The Sudanese crude oil is regarded as one of the simplest types of crude in the world as it contains no percentage of sulfur which reacts with water to form sulfuric acid that negatively impact the production facilities and transportation lines due its corrosiveness . How ever it suffers other problems represented by the high viscosity and high percentage of wax. These characteristics prevail in the crude oil produced by Petrodar company causing some very serious technical problems affectively the transfer of crude which is transported long distances from production fields to the port export terminal a .matter that affect directly the cost of production and the quality A detailed study was made on the system adopted in collecting crude oil from different wells and physical and chemical processing to which crude is subjected through different stages of production and also study of the behaviour .of crude in the pipeline during transportation processes Samples were collected from the fields of production at Adar-yale, Agordeed and Palouge and also samples were collected after the initial and final treatment .at CPF No samples of the recently introduced field such as Gummry, Gasub, Moleeta, .were collected, but their specifications were inferred from available data Physical and chemical properties that have been studies were amount of wax, is in the range 23-31% and asphaltene which was around 0.1%; resin content that ranged from 13-7%, deposits was 0.01%, water cut was 0.05% and the carbon number distribution in the crude which ranged between 7 to35 carbon atoms. The pour point was found range from 39-42 C; also the boiling point was in the range from 70 °C - 533+ C o and density specifications according the .American Institute of petroleum was 24 Mechanical effects and temperature influence in viscosity were also studied. The composition of the Dar Blend was found to influence the flow characteristics of the crude. Presence of asphalting and resins reduce the .deposition of wax crystals and enhance, therefore, the fluidity of the crude When increasing the rate of shear at a temperature higher than 42C doesn’t .effect on viscosity, it became constant ‫‪found that addition of PPD had no effect in altering the viscosity even at a dose‬‬ ‫‪.(of 1000-4000 ppm (i.e, ten folds greater than the usual dose‬‬ ‫‪It is either unsuitable additives were used by Dar Company or the additives‬‬ ‫‪were expired, which in either case necessitate reevaluations of using such‬‬ ‫‪.additives‬‬