M madhi - M.Sc. Student of Petroleum University of Technology, Department of Petroleum Engineering, Ahwaz, Iran,
m Mohammadian - M.Sc. Student of Petroleum University of Technology, Department of Gas Engineering, Ahwaz, Iran,
m ahmadi - M.Sc. Student of Petroleum University of Technology, Department of Chemical Engineering, Abadan, Iran,

One of the most severe problems during production from heavy crude oil reservoirs is the formation of Asphaltene Precipitation and Deposition is a serious problem which can reduce the oil recovery by reducing reservoir permeability and altering the wettability. It can plug wells and flow lines through deposition and also cause separation difficulties at the separation facilities. So one of the economical ways to prevent such incidents is using of the chemicals with different structure and functional group which is called Asphaltene inhibitor. In this study, three commercial and four non-commercial inhibitors were investigated. An extensive literature survey was done, then effect of functional groups and structure of inhibitors on Asphaltene precipitation were studied and it seems clear that the nature of Asphaltene (structure and amount of impurities presented) has a significant impact on the selection of inhibitors. Static and dynamic tests were designed for evaluation of inhibitors and existence of hydrogen bonding, π-π interaction and acid-base interaction mechanisms were confirmed. It was shown that salicylic acid with extra OH group has better efficiency in reduction of Asphaltene than benzoic acid. The results suggest that 600 ppm of CTAB was approximately optimum concentration for the studied crude oil. Effect of chosen inhibitors on Asphaltene precipitation and consequently deposition in porous media was investigated

Asphaltene Precipittion, Asphaltene Depossition, Asphaltene inhibitor