Crude Oil Blending Effects on Asphaltene Stability in Refinery Fouling

It has been known for some time that blending of incompatible crude oils may lead to asphaltene destabilization. The link between such asphaltene destabilization and their subsequent fouling of equipment in refinery operations was established in this study. Several refinery crude blends known to cause problems ranging from desalter upsets to fouling in pre-heat train were studied. Stability analysis of the crudes and their blends using a solvent titration method with a laser-based solids detection system showed that destabilization of the asphaltenes is caused, in the main, by blending of incompatible crudes. The stability data showed that the individual crudes had a high, medium, or low fouling potential. The blends of those that are incompatible however showed increased instability and may be the cause of the fouling problems encountered in the pre-heat train heat exchangers during their processing.