(58d) Asphaltene Solubility and Fluid Compatibility

Asphaltenes are held in petroleum by dispersion/solution in a delicate balance that is easily upset, causing plugging of well bores during production and fouling of heat exchangers and furnace tubes during refining. Methods will be reviewed for predicting the onset of asphaltene precipitation on reduction of the pressure during production or on the blending of crude oils after production. Since petroleum contains only a small amount of atoms other than carbon, hydrogen, and sulfur, the major force of interaction is of the van der Waals type. As a result, practical prediction methods for petroleum macromolecules, including asphaltenes, can be used that were previously found to be only a rough approximation when applied to organic polymers.