M Tavakkoli - Chemical and Petroleum Engineering Department, Sharif University of Technology, Tehran, Iran ۲ Petroleum Research Center, Petroleum University of Technology, Tehran, Iran
R Kharrat - Petroleum Research Center, Petroleum University of Technology, Tehran, Iran
M Masihi - Chemical and Petroleum Engineering Department, Sharif University of Technology, Tehran, Iran
M.H. Ghazanfari - Chemical and Petroleum Engineering Department, Sharif University of Technology, Tehran, Iran ۲ Petroleum Research Center, Petroleum University of Technology, Tehran, Iran

In this work, a computer code which is based on Thermodynamic Micellization Model has been developed, and, used for predicting of asphaltene precipitation data reported in the literature under gas injection condition. In the thermodynamic micellization model, a new approach has been proposed. First, the characterization method, which is usually used in the thermodynamic solid model, was applied and the total amount of resin and asphaltene content were predicted. Then, the thermodynamic micellization model, using the obtained model parameters from sensitivityanalysis, was applied to predict the asphaltene precipitation data. It has been observed from sensibility analysis that the thermodynamic micellization model is highly sensitive to the proposed parameter, interaction coefficient between the asphaltene component and the light hydrocarbon components. The model sensitivity to this new parameter is due to the new characterization method chosen for the thermodynamic micellization model. It has been found that the model predictions are also highly sensitive to the chosen method for the characterization. This new approach resulted in a significant improvement in the model predictions of asphaltene precipitation data under gas titration condition. Especially, for the predictions of the model at high concentrations of injected gas, good agreements were observed which could rarely be found in the available literature.

Asphaltene precipitation, Thermodynamic Modeling, Thermodynamic Micellization Model, Gas injection