A New Approach to Predict Phase Behaviour of Non-Ideal Organic Systems.(Abstract)

摘要

Flow assurance has been an important concern, especially in deepwater crude oil production scenario, where hydrate and wax blockage have taken place frequently. The offshore production activities increased its importance in the last years, it has become a major concern for oil industry to develop codes to deal with this costly problem on a preventive basis. Regarding to wax deposition it has caused several pipeline blockage and production losses. Different models have been proposed to predict paraffin-wax phase equilibrium. For complex non-ideal mixtures, e.g. petroleum, it is necessary to consider the different interactions of its many different components to predict the phase behaviour of such mixtures. This work introduces a new approach to predict paraffin phase behaviour in both polar and non-polar solvents. Most of thermodynamic models to predict organic compounds phase behaviour are based on one component solubility parameter which represents the modulus of a three components actual solubility parameter, that take into account hydrogen bond, van der Walls forces and dipolar momentum. Although the use of a unique dimension solubility parameter leads to simpler model, it can lead, on the other hand, to wrong conclusions too, as it will be shown in this work. This can be critical when ones are supposed to model phase behaviour involving polar and nom-polar compounds. Most of petroleum is in this situation because they have paraffin, aromatics, resins and asphaltenes molecules.