Maximus
Asphaltene Predictions

Asphaltenes are polar compounds which are stabilised in crude oil by the presence of resins. If the oil is diluted by light hydrocarbons, the resin concentration is reduced and a point may be reached when the asphaltene is no longer stabilised and flocculates forming a solid deposit. Because the stabilising action of the resins works through the mechanism of polar interactions, their effect becomes weaker as the temperature rises, i.e. flocculation may occur as the temperature increases. However, as the temperature increases further the asphaltene becomes more soluble in the oil. Thus, depending on the temperature and the composition of the oil, it is possible to find cases where flocculation both increases and decreases with increasing temperature.

Through Maximus, it is also possible to access MULTIFLASH’s latest asphaltene flocculation methods. For more details of these asphaltene models please download Infochem’s recent paper (Edmonds et al 1999, A New Method to give Quantitative Prediction of Asphaltene Deposition from Petroleum Fluids) from its website www.infochemuk.com.

These methods available in Maximus allow the User to predict asphaltene phase behaviour, identifying regions where asphaltene flocculation poses a risk to operations. This means that in a Maximus production system model, it is possible to trace the fluids through the entire production system assessing the risk of asphaltene flocculation as the conditions of pressure and temperature change and as the composition changes, perhaps due to gas injection or commingling with other production fluids.