Title : Comprehensive experimental assessment of the compatibility and stability of sarrir and Bu attifel crude oil blends
Abstract:
This study is a part of investigating the possibility of blending two crude oils obtained from Libyan oil fields, namely Bu Attifel and Sarrir crude oils with different ratios, prior to blending, the crude oils must be compatible to avoid phase out and precipitation of asphaltene from the bulk of crude. To examine the stability of both crudes and their blends, the oil compatibility model using Microscopic, colloidal instability index (CII) using SARA analysis and asphaltene stabilization test using Turbiscan tests were conducted in the Petroleum research Center (PRC) laboratories. Compatibility tests were carried out with both crude oils, the insolubility number, (IN) and the solubility blending number, (SBN) for both crude oils and their blends were calculated, the criteria for compatibility of any blend is that the volume average solubility blending number (SBN) is greater than the insolubility number (IN) of any component in the blend, the results indicated that both crudes were compatible.
To support the results of compatibility tests the SARA analysis was done for the fractional determination of (Saturates, aromatics, resins and asphaltenes) content. From this result the colloidal Instability index (CII) and resin to asphaltenes ratio (R/A) were calculated for crudes and their blends. The results indicate that Sarrir crude oil, characterised by a higher (R/A) ratio and lower (CII), demonstrates greater stability than Bu Attifel crude oil. Moreover, as the proportion of Sarrir crude increases within the blend, both the (CII) and (R/A) values improve, resulting in enhanced stability of the blends. The asphaltene stabilization test for the crudes and their blends was carried out using the Turbiscan MA200, following the ASTM D7061-04 standard method. Results indicate that Sarrir crude is more stable compared to Bu Attifel crude, which demonstrates only moderate stability. The (CII) and (R/A) values were evaluated alongside the solubility number (SBN) for each crude and their blends, as well as Turbiscan results. The solubility blending numbers (SBN) indicate that the crudes are compatible; furthermore, a comparison of (R/A) and (SBN) for the blends suggests these metrics complement one another. Experimental data consistently demonstrate that blends of both crudes exhibit enhanced stability.
